Creatine 101: What It Is and What It Does

Creatine is the undisputed king of sports nutrition supplements, but how does it work and what are the benefits of this best-selling pre-workout ingredient?

Over the past 20 years, sports nutrition has escalated by leaps and bounds, and in that time, athletes, bodybuilders, and casual gym rats have been inundated by all sorts of shiny new herbal extracts, synthetic ergogenics, and isolated amino acids that promise to deliver life-changing results. Yet, few of these compounds have ever delivered on the hype.

There has been a compound, however, that’s been a staple of lifters and athletes for decades prior to the explosion in popularity of sports nutrition supplements. That ingredient is none other than creatine monohydrate.

Most of you reading this have heard of creatine, and you’ve probably even experienced some of the benefits of creatine supplementation for yourself, such as enhances lean mass gains or better athletic performance.

But, how does creatine work? Is creatine safe for women? And, how much creatine should I take?

We’ve got all these questions answered and a whole lot more in store as we take an in-depth look at creatine — the king of sports supplements.

What is Creatine?

Creatine is a substance naturally produced in the body from the amino acids glycine, arginine, and methionine. [1,2] Chemically, creatine is known by the name α-methyl guanidine-acetic acid, but seeing as this isn’t a biochemistry course, we’ll leave it at just plain old creatine.

Creatine is primarily stored (~95%) in your skeletal muscles in the form of phosphocreatine, and the remaining 5% is stored in the kidneys, liver, and brain. [1] It’s also found in a number of other foods in our diet, especially red meat.

Now, the amount of creatine each of us stores in our body is going to depend on a few factors, including:

  • Exercise
  • Amount of Lean Muscle Mass
  • Levels of Anabolic Hormones such as IGF-1 (insulin-like growth factor-1) and Testosterone
  • Meat Consumption

What Does Creatine Do?

Following ingestion, creatine binds to a molecule of phosphate to form phosphocreatine or creatine phosphate.

Why is this important?

Whenever you ingest nutrients (whole foods, protein powder, BCAAs, etc.), your digestive system breaks down these nutrients to get energy so that it can power all of the other chemical and physiological processes that go on in the body.

These processes require energy in the form of ATP (adenosine triphosphate). ATP also serves as the primary fuel for your muscles during high-intensity exercise like resistance training or sprinting.

The way ATP provides energy is by donating one of its three phosphate groups (remember ATP stands for adenosine TRI-phosphate, meaning it has three phosphates attached to one molecule of adenosine).

After donating its phosphate group, ATP now becomes ADP (adenosine DI-phosphate), meaning it has two phosphates instead of three.[1] Now, the body can readily use ATP for energy production, but it’s not so fond of ADP for generating energy. So, your body reserves this ADP molecule and saves it until another phosphate is freed up and it can be recycled into ATP.

Now, here’s where creatine enters the picture.

As we mentioned above, creatine is stored in the body as phospho-creatine, meaning it has an extra phosphate molecule to donate. Creatine, being the noble fellow that it is, sacrifices its phosphate group for the good of your body, donating it to ADP and transforming the seemingly useless ADP into the energy-producing powerhouse that is ATP.

Therefore, the primary benefit of creatine resides in its ability to rapidly regenerate ATP, which translates to a number of performance and physique benefits that we’ll discuss in more detail now!

Benefits of Creatine

Improves ATP Production

As we just mentioned, the primary benefit of ATP comes from its ability to rapidly replenish ATP stores in the body.

ATP serves as the “cellular currency” of energy production in the body, meaning that once your ATP stores are empty, your body has to start breaking down glycogen or pulling in glucose and fats from the bloodstream to power your muscles during training. So, the more ATP you have, the longer you can train before succumbing to fatigue, which leads to greater gains in size, strength, and performance. [1,2] 

Muscle Builder

Creatine has been extensive studies and shown time after time to improve lean body mass (a.k.a. Muscle mass) as well as performance during intense training. [4,5] Studies note that supplementing with creatine monohydrate while performance resistance training increase muscle cell nuclei concentration, which promotes the greater growth of lean muscle. [6]

Other research notes that when creatine and weight lifting are combined, it increases fat-free mass (i.e. muscle), muscle morphology, and physical performance. [7]

Part of this is due to creatine’s ability to help you grind out more reps (due to better energy production), but creatine also helps stunt myostatin production. [8] In case you weren’t aware, myostatin is a devious little protein that puts the brakes on muscle growth in the body. By inhibiting it, creatine helps promote greater muscle cell growth and differentiation.

Strength Booster

One of the truly exceptional things about creatine is that not only does it help muscles to grow bigger, it also helps them become stronger, too. Research has shown that weightlifters using creatine increased their one-rep max on bench press of 43%, compared to those who did not use creatine while training. [9,10]

Hydration Support

We’ve spent the majority of this article discussing the primary function of creatine, in regards to its ability to enhance ATP regeneration in the body, but it also serves another very important role in regards to health and performance.

Creatine monohydrate also functions as a natural osmolyte, that helps increase the water content within muscle cells. [15] Because of this cell-hydrating effect, creatine increases cell volume, which has a multitude of benefits including better stamina, bigger “water” pumps, and muscle growth.

Brain Booster

Up top, we mentioned that the majority of creatine is stored in the brain, but a small percentage is also stored in your brain. As it turns out, creatine supplementation also imparts some brain gains as well, especially for vegans and vegetarians.

Research notes that when adult vegetarians supplemented with creatine, they experienced better working memory and intelligence. The reason vegetarians were used for the study was that they tend to have low levels of endogenous creatine due to their low meat intake. [12,13]

But that’s not all…

Creatine has also been shown to improve mental performance following 36 hours of sleep deprivation [14], making this a great supplement to use if you’re one who doesn’t get adequate amounts of sleep each night.

Neuroprotector

Creatine not only helps our brains to function at a higher level, but it may also protect us from certain neurological diseases as well. Supplemental creatine can act as a substrate for creatine kinase, which may increase phosphocreatine and protect against ATP depletion, which has been documented to exert neuroprotective benefits. [17]

Other studies note that supplementing with creatine can improve quality of life and reduce symptoms in individuals with cognitive dysfunction. [16] Furthermore, creatine supplementation has been documented to prevent up to 90% of the decline in dopamine levels in animals. [17]

You may be asking, “why is that important?”

Well, chronically falling levels of dopamine production are a tell-tale sign of Parkinson’s disease.

Additional research has noted that when patients with Parkinson’s were given creatine it reduced their decline in cognitive function and increased their strength. [18,19]

Improves Symptoms of Depression

Consuming creatine daily has been noted to lessen symptoms of depression in women, including ones who didn’t respond to SSRI prescriptions (the “standard” treatment for depression). [20]

Additional studies have documented that creatine supplementation is beneficial for the treatment of a number of other diseases including [21,22,23]: 

  • Alzheimer’s
  • Ischemic Stroke
  • Huntington’s Disease
  • Amyotrophic Lateral Sclerosis
  • Epilepsy
  • Brain or Spinal Cord Injuries

Combats Fatigue

We’ve mentioned previously that creatine improves stamina and endurance via improve ATP production, but it also helps you last longer during your workouts due to its unique ability to reduce neuromuscular fatigue and perceived fatigue when training.[24,25]

Creatine also has been shown to boost mood following sleep deprivation or psychologically-intensive tasks. [26]

Improves Injury Recovery Rate

Not only does creatine improve your performance on the field, it also helps you get back there following an injury. Research conducted in healthy subjects has shown that creatine supplementation significantly improves recovery of knee extensor muscle function after injury. [33]

Heart Helper

In addition to its role in muscle building, creatine also helps fortify your cardiovascular system as well, protecting the heart against stress and improving its ability to repair. [29]

Creatine production also helps reduce homocysteine levels, which if you weren’t aware, elevated levels of homocysteine are associated with an increased risk of cardiovascular disease.

Further research has shown that when creatine is supplemented at a dose of 20 grams per day, it lowers cholesterol. [30]

Supports Skeletal System

Creatine enhances osteoblast formation, which increases bone formation and bone repair. [31] Additional research in older women with osteoarthritis has noted that creatine supplementation helps reduce pain associated with the disorder. [32]

Steadies Blood Sugar

We’re still not done with the benefits of creatine yet!

As you well know, type 2 diabetes and metabolic syndrome are two of the most common chronic diseases affecting our population these days. At the core of these two diseases is a combination of chronically elevated blood sugar levels and insulin resistance.

As it turns out, creatine might be an unsung hero of sorts for diabetics. Research notes that supplementing with creatine can significantly reduce blood sugar measurements during a glucose tolerance test in healthy men performing aerobic exercise. [27]

A 2016 systematic review also confirmed these findings when it concluded that creatine is useful for controlling blood glucose when combined with exercise. [28]

Beneficial for Expectant Mothers

Studies involving pregnant women have noted that supplementing with creatine can benefit baby development in the instances of oxygen deprivation or premature birth. [34]

Potential Testosterone Booster

The final benefit of creatine is more of an “outlier” of sorts, as it’s never really been thoroughly investigated, but still, warrant mentioning.

In addition to all of the muscle and performance benefits mentioned prior, creatine may also boost the most anabolic hormone of all — testosterone.

Research using very high doses of creatine (100mg/kg) noted that it successfully increased testosterone levels. [11]

How much is that for the average man?

For the average 175lb male, you’d need around 8 grams of creatine to get the potential testosterone boosting benefits of this all-time muscle builder.

Speaking of dosing…

How Much Creatine Should I Take?

All sorts of dosing and loading protocols have been used with creatine studies over the years.

Some protocols call for loading up to 20 grams per day (divided into 4-5 doses) for 3-4 days to accelerate the rate of saturation, but for the average lifter looking to experience all that creatine has to offer, a standard dose of 5 grams per day every day of creatine monohydrate is recommended.

When to Take Creatine

The great thing about creatine, unlike other supplements, is that you really can take it any time of day. You see, you start to experience the benefits of creatine once your muscles are saturated with it. It doesn’t offer an acute benefit, like what caffeine or citrulline malate does.

Therefore, you can take your creatine pre-workout, post workout, intra-workout, or any other time of day. It doesn’t really matter so long as you get your 5 grams in every day.

However, there can be an argument made for an “optimal” time to take creatine is the post-workout period, when insulin sensitivity is highest, meaning it will be rapidly taken up and stored in your muscles. But again, so long as you’re taking in your 5 grams of creatine monohydrate every day, you will be fine.

Takeaway

Creatine monohydrate has stood the test of time as the de facto king of the supplement world. It’s proven time and time again to enhance lean mass, strength, power, and performance. Creatine also comes with a drove of other benefits for your brain and heart, too.

When you add it all together, creatine supplementation is really a no-brainer and should be a part of every fitness enthusiasts stack, young or old, male or female.

References

  1. Persky AM, Brazeau GA. Clinical Pharmacology of the Dietary Supplement Creatine Monohydrate. Pharmacol Rev. 2001;53(2):161 LP-176.
  2. Bird SP. Creatine Supplementation and Exercise Performance: A Brief Review. Journal of Sports Science & Medicine. 2003;2(4):123-132.
  3. The Editors of Encyclopedia Britannica. (2016, August 19). Adenosine triphosphate. Retrieved October 17, 2017, from
  4. Branch JD. Effect of creatine supplementation on body composition and performance: a meta-analysis. Int J Sport Nutr Exerc Metab. 2003;13(2):198-226.
  5. Parise G, Mihic S, MacLennan D, Yarasheski KE, Tarnopolsky MA. Effects of acute creatine monohydrate supplementation on leucine kinetics and mixed-muscle protein synthesis. J Appl Physiol. 2001;91(3):1041-1047. doi:10.1152/jappl.2001.91.3.1041.
  6. Olsen S, Aagaard P, Kadi F, et al. Creatine supplementation augments the increase in satellite cell and myonuclei number in human skeletal muscle induced by strength training. The Journal of Physiology. 2006;573(Pt 2):525-534. doi:10.1113/jphysiol.2006.107359.
  7. Volek JS, Duncan ND, Mazzetti SA, et al. Performance and muscle fiber adaptations to creatine supplementation and heavy resistance training. Med Sci Sports Exerc. 1999;31(8):1147-1156.
  8. Saremi A, Gharakhanloo R, Sharghi S, Gharaati MR, Larijani B, Omidfar K. Effects of oral creatine and resistance training on serum myostatin and GASP-1. Mol Cell Endocrinol. 2010;317(1-2):25-30. doi:10.1016/j.mce.2009.12.019.
  9. Earnest CP, Snell PG, Rodriguez R, Almada AL, Mitchell TL. The effect of creatine monohydrate ingestion on anaerobic power indices, muscular strength and body composition. Acta Physiol Scand. 1995;153(2):207-209. doi:10.1111/j.1748-1716.1995.tb09854.x.
  10. Rawson ES, Volek JS. Effects of creatine supplementation and resistance training on muscle strength and weightlifting performance. J strength Cond Res. 2003;17(4):822-831.
  11. Cook CJ, Crewther BT, Kilduff LP, Drawer S, Gaviglio CM. Skill execution and sleep deprivation: effects of acute caffeine or creatine supplementation – a randomized placebo-controlled trial. Journal of the International Society of Sports Nutrition. 2011;8:2. doi:10.1186/1550-2783-8-2.
  12. Rae C, Digney AL, McEwan SR, Bates TC. Oral creatine monohydrate supplementation improves brain performance: a double-blind, placebo-controlled, cross-over trial. Proceedings of the Royal Society B: Biological Sciences. 2003;270(1529):2147-2150. doi:10.1098/rspb.2003.2492.
  13. Benton D, Donohoe R. The influence of creatine supplementation on the cognitive functioning of vegetarians and omnivores. Br J Nutr. 2011;105(7):1100-1105. doi:10.1017/S0007114510004733.
  14. McMorris T, Harris RC, Howard AN, et al. Creatine supplementation, sleep deprivation, cortisol, melatonin and behavior. Physiol Behav. 2007;90(1):21-28. doi:10.1016/j.physbeh.2006.08.024.
  15. Burg MB, Ferraris JD. Intracellular Organic Osmolytes: Function and Regulation. The Journal of Biological Chemistry. 2008;283(12):7309-7313. doi:10.1074/jbc.R700042200.
  16. Rawson ES, Venezia AC. Use of creatine in the elderly and evidence for effects on cognitive function in  young and old. Amino Acids. 2011;40(5):1349-1362. doi:10.1007/s00726-011-0855-9.
  17. Matthews RT, Ferrante RJ, Klivenyi P, et al. Creatine and cyclocreatine attenuate MPTP neurotoxicity. Exp Neurol. 1999;157(1):142-149. doi:10.1006/exnr.1999.7049.
  18. Li Z, Wang P, Yu Z, et al. The effect of creatine and coenzyme q10 combination therapy on mild cognitive impairment in Parkinson’s disease. Eur Neurol. 2015;73(3-4):205-211. doi:10.1159/000377676.
  19. Hass CJ, Collins MA, Juncos JL. Resistance training with creatine monohydrate improves upper-body strength in patients with Parkinson disease: a randomized trial. Neurorehabil Neural Repair. 2007;21(2):107-115. doi:10.1177/1545968306293449.
  20. Kondo DG, Sung Y-H, Hellem TL, et al. Open-label adjunctive creatine for female adolescents with SSRI-resistant major depressive disorder: A 31-phosphorus magnetic resonance spectroscopy study. Journal of affective disorders. 2011;135(0):354-361. doi:10.1016/j.jad.2011.07.010.
  21. Bürklen TS, Schlattner U, Homayouni R, et al. The Creatine Kinase/Creatine Connection to Alzheimer’s Disease: CK Inactivation, APP-CK Complexes, and Focal Creatine Deposits. Journal of Biomedicine and Biotechnology. 2006;2006:35936. doi:10.1155/JBB/2006/35936.
  22. Prass K, Royl G, Lindauer U, et al. Improved reperfusion and neuroprotection by creatine in a mouse model of stroke. J Cereb Blood Flow Metab. 2007;27(3):452-459. doi:10.1038/sj.jcbfm.9600351.
  23. Rambo LM, Ribeiro LR, Oliveira MS, et al. Additive anticonvulsant effects of creatine supplementation and physical exercise against pentylenetetrazol-induced seizures. Neurochem Int. 2009;55(5):333-340. doi:10.1016/j.neuint.2009.04.007.
  24. Smith AE, Walter AA, Herda TJ, et al. Effects of creatine loading on electromyographic fatigue threshold during cycle ergometry in college-aged women. Journal of the International Society of Sports Nutrition. 2007;4:20. doi:10.1186/1550-2783-4-20.
  25. Hadjicharalambous M, Kilduff LP, Pitsiladis YP. Brain serotonin and dopamine modulators, perceptual responses and endurance performance during exercise in the heat following creatine supplementation. Journal of the International Society of Sports Nutrition. 2008;5:14. doi:10.1186/1550-2783-5-14.
  26. McMorris T, Harris RC, Swain J, et al. Effect of creatine supplementation and sleep deprivation, with mild exercise, on  cognitive and psychomotor performance, mood state, and plasma concentrations of catecholamines and cortisol. Psychopharmacology (Berl). 2006;185(1):93-103. doi:10.1007/s00213-005-0269-z.
  27. Gualano B, Novaes RB, Artioli GG, et al. Effects of creatine supplementation on glucose tolerance and insulin sensitivity  in sedentary healthy males undergoing aerobic training. Amino Acids. 2008;34(2):245-250. doi:10.1007/s00726-007-0508-1.
  28. Pinto CL, Botelho PB, Pimentel GD, Campos-Ferraz PL, Mota JF. Creatine supplementation and glycemic control: a systematic review. Amino Acids. 2016;48(9):2103-2129. doi:10.1007/s00726-016-2277-1.
  29. Spindler M, Meyer K, Stromer H, et al. Creatine kinase-deficient hearts exhibit increased susceptibility to ischemia-reperfusion injury and impaired calcium homeostasis. Am J Physiol Heart Circ Physiol. 2004;287(3):H1039-45. doi:10.1152/ajpheart.01016.2003.
  30. Earnest CP, Almada AL, Mitchell TL. High-performance capillary electrophoresis-pure creatine monohydrate reduces blood lipids in men and women. Clin Sci (Lond). 1996;91(1):113-118.
  31. Gerber I, ap Gwynn I, Alini M, Wallimann T. Stimulatory effects of creatine on metabolic activity, differentiation and mineralization of primary osteoblast-like cells in monolayer and micromass cell cultures. Eur Cell Mater. 2005;10:8-22.
  32. Neves MJ, Gualano B, Roschel H, et al. Beneficial effect of creatine supplementation in knee osteoarthritis. Med Sci Sports Exerc. 2011;43(8):1538-1543. doi:10.1249/MSS.0b013e3182118592.
  33. Cooke MB, Rybalka E, Williams AD, Cribb PJ, Hayes A. Creatine supplementation enhances muscle force recovery after eccentrically-induced muscle damage in healthy individuals. Journal of the International Society of Sports Nutrition. 2009;6:13. doi:10.1186/1550-2783-6-13.
  34. Dickinson H, Ellery S, Ireland Z, LaRosa D, Snow R, Walker DW. Creatine supplementation during pregnancy: summary of experimental studies suggesting a treatment to improve fetal and neonatal morbidity and reduce mortality in high-risk human pregnancy. BMC Pregnancy and Childbirth. 2014;14:150. doi:10.1186/1471-2393-14-150.
  35. Jäger, Ralf; Analysis of the Efficacy, Safety, and Regulatory Status of Novel Forms of Creatine. Amino Acids 40.5 (2011): 1369-383.
  36. Buford TW, Kreider RB, Stout JR, et al. International Society of Sports Nutrition position stand: creatine supplementation and exercise. Journal of the International Society of Sports Nutrition. 2007;4:6. doi:10.1186/1550-2783-4-6.

Training Fasted: Pros and Cons

If you want to know the pros and cons of training fasted and whether or not it is superior for losing fat or building muscle, you want to read this article.

For decades, if you wanted to lose weight and get rid of that unsightly body fat, you performed hour after hour of fasted cardio.

Entire lifetimes have been spent slogging it out on treadmills, bikes and ellipticals under the premise that training with no food in your stomach (a.k.a. training fasted) was the one true way to banish body fat for good.

And, off the bat, it sounds like a pretty solid idea.

When deprived of food, the body inherently turns to stored energy (i.e. body fat) for fuel, but does that logic hold up in research?

Does training fasted lead to better fat loss and body composition?

We answer all of those questions and more in this review of the pros and cons of fasted training.

What is Fasted Training?

Fasted training is simply performing exercise when food is no longer being digested or absorbed by your body.

Your body enters this fasted state approximately three to six hours after you eat a meal. The time it takes to fully digest and absorb a given meal depends on the overall size (caloric density) of the meal, as well as how much protein, fat, carbohydrates, and fiber constitute said meal.

The greater amount of fiber, fat, and/or protein a meal contains, the longer it will take to digest.

Benefits (Pros) of Fasted Cardio

Enhances Fat Burning

Exercise science has pretty well established that performing fasted cardio burns significantly more fat than performing the same bout of cardio in a fed state. A 2016 systematic review and meta-analysis including 27 studies even concluded that: [1] 

“… aerobic exercise performed in the fasted state induces higher fat oxidation than exercise performed in the fed state.”

The reason your body burns more fat when you train fasted as opposed to when it’s fed is pretty simple, and it’s rooted in your physiology. You see, the body is incredibly adept at burning carbohydrates for fuel during exercise. [2] And, when more of it is available (i.e. in the 2-3 hours following a meal), your body will by default burn those carbohydrates first, then turn to fat for the additional energy, should it be needed.

This is the main reason why study after study over the decades has noted that when people consume carbohydrates prior to exercise, they inherently burn more carbohydrate for fuel, along with less fat, during their workout. [3,4]

So, to “force” your body, in a sense, to utilize fat for fuel, you avoid eating prior to training.

Helps Eliminate Unwanted Belly Fat

No matter how slim, toned, or ripped you may be, you’re bound to have at least one area on your body that holds some “stubborn” fat. Be it the hips, thighs, or lower abdomen, each of us has one region of fat that won’t go away, regardless of how much we diet or exercise.

But, just because we have trouble with that one area of stubborn fat, doesn’t mean we have poor genetics. You see, stubborn fat is a “defense mechanism” of sorts your body has to protect against extremely low levels of body fat.

The good news is, is that fasted cardio can help you eliminate stubborn fat.

How so?

Let’s review a bit about what makes stubborn body fat so “stubborn” anyway.

Every one of the fat cells in your body has receptors on them, and chemicals your body produces called catecholamines bind to these receptors. Now, these fat cell receptors fall into one of two categories — alpha receptors and beta receptors. [5,6]

We’ll spare you the complex inner workings of how these receptors specifically affect fat loss/storage, and summarize it as basically:

  • Alpha receptors — block fat burning
  • Beta receptors — promote fat burning

The more alpha receptors a fat cell has, the more “stubborn” it is to release its stored fatty acids for oxidation, and the more beta receptors a fat cell has, the more readily it can be accessed.

As you probably guessed, the regions of fat on your body that won’t see to go away are more densely packed with alpha receptors than beta receptors, which is part of the reason they are harder to get rid.

But it doesn’t end there.

Regions of stubborn body fat also receive less blood flow, and this brings us back to our discussion of catecholamines and alpha/beta receptors.

The less blood flow an area of fat your body receives, the fewer catecholamines those fat cells are exposed two. Coupled with the fact that those areas already have a higher concentration of alpha receptors than beta receptors, and you’ve got the perfect recipe for incredibly stubborn body fat that just won’t go away.

Now, here’s where the real beauty of fasted cardio comes into the picture.

When you train in a fasted state, blood flow to the abdominal region is increased [8], which means that those areas of stubborn body fat receive greater amounts of those fat burning chemicals called catecholamines.

You can further up the ante on eliminating stubborn body fat, by supplementing with ingredients such as yohimbine, which serve as alpha receptor antagonists. These compounds bind to alpha receptors, turning them “off” in a sense and allowing greater amounts of catecholamines like adrenaline and noradrenaline to bind to beta receptors and “open the floodgates” to help burn stubborn body fat.

Workout Done for the Day

One of the less discussed benefits of training fasted is that by working out first thing in the morning, you’ve already ticked the “work out” box of the day, and now you have the rest of the day to focus on the more important things like work, family, etc.

Plus, as an added bonus, you’ll also have greater energy, mood, and focus thanks to the flood of brain-boosting chemicals that are released during the course of exercise, helping you be more productive during the early part of your day when so many other people can’t seem to function without 4-6 cups of coffee.

Avoid Stomach Upset

For many people, they train fasted simply because training shortly after eating leads to indigestion, nausea, and just a general feeling of sluggishness and lethargy. By training fasted, you avoid the rather unpleasant sensation of feeling like you’re going to puke after a set of heavy squats (at least partially) or high-intensity interval training.

The Drawback (Cons) of Fasted Cardio

Increased Potential to “Bonking”

Food is fuel for our body.

If you train first thing in the morning upon waking, and your muscles have fully replenished their glycogen stores overnight, it’s very possible you will “bonk” or “hit a wall” during your workout.

This “bonking” sensation is caused by low blood glucose and glycogen levels in the body. In a sense, your muscles are running low and fuel, and your ability to hit “top speed” is significantly diminished.

But what if eating prior to training causes my stomach to feel upset?

If you’re one of those people who doesn’t like to train with a full-feeling stomach, yet still seems to bonk during their workouts, try having a small, low-fiber snack like a banana or glass of orange juice 30-45 minutes prior to training.

These options are rapidly digested, meaning they’ll be in and out of your stomach quickly. You’ll avoid the full stomach feeling and have ample glucose to power you through your training.

Reduced Training Intensity

Training fasted, while it might be good for burning belly fat, isn’t really all that ideal when it comes to high-intensity forms of exercise, such as sprinting or heavy resistance training.

Remember, glucose (glycogen) is the kind of fuel your muscles thrive on for intense exercise, regardless of what the keto, primal, and low carb communities tell you. Simply put, if you want a superior quality workout, you want some form of carbohydrate in your system.

Your body cannot oxidize fat as quickly as it can glucose [12].

You see, the body will prioritize which nutrient it burns for fuel, provided all are available. This order of energy substrate utilization is:

  1. Blood Glucose (blood sugar)
  2. Muscle Glycogen (the storage form of glucose)
  3. Body Fat
  4. Protein (pulled from muscle)

So, what this means, is that if carbs are available, whether in the form of circulating blood sugar or muscle glycogen, your body will burn it before it touches body fat or dietary fat. This also means that during high-intensity exercise, your body will want carbohydrates to burn, as it is the nutrient most easily converted to usable energy. It can use fat, but it’s far from optimal and not very efficient.

As such, if you want to maximize performance, you don’t want to train on a fasted stomach.

Higher Cortisol Levels

Cortisol is the stress hormone your body releases when energy stores are low. Performing exercise of any kind prompts an increase in cortisol, as does fasting. Do both of these actions frequently enough (i.e. fasted training) and you may start to develop chronically elevated cortisol levels, which promotes fat storage and reduce fat burning. [9,10]

The Verdict on Fasted Training

So, it appears that there’s both good and bad when it comes to fasted training, as it is with most things in life.

But, there are a few other things that warrant consideration.

First, we know that that the number of calories you burn during a workout account for a very small fraction of your total daily energy expenditure (TDEE). What you eat during the day and how much of a deficit you use has a far greater impact on your ability to lose weight than whether you train fasted or not.

There’s even some research by Dr. Brad Schoenfeld et al. that shows that there is no difference in body composition changes (i.e. fat loss) when it comes to training fasted vs training fed. [11]

Additionally, there’s also some research noting that if you burn greater amounts of fat during an earlier part of the day (i.e. performing fasted cardio first thing in the morning), your body will actually burn less fat later on in the day. [13]

Essentially what happens, is that the body more or less “compensates” for the increased fat burning it did earlier in the day by downregulating fat burning and upregulating glucose burning the rest of the day.

In the end, training fasted can be useful for some morning bouts of cardio if you’re trying to lose some stubborn body fat, but if you’re looking to maximize performance or just lose fat in general, training fed would be the superior option.

Training in a fed state ensures that energy stores are topped off and you’ll be able to push harder in your workouts, which allows you to burn more calories, ultimately creating a larger caloric deficit. This ultimately winds up in a better fat loss and body composition.

But, for those days when you want to sweat it out first thing in the morning on an empty stomach and rid stubborn belly fat for good, there’s only one option…

Steel Sweat — THE Best Pre-Workout for Fasted Cardio

Steel Sweat™ is a metabolic catalyst that increases thermogenesis, energy expenditure, and fat burning. The all-natural ingredients in Steel Sweat™ help burn stubborn body fat and help you achieve the lean, trim physique that you’ve strived so long to achieve.

Simply mix up a scoop first thing in the morning before hitting the gym and you’re on your way to banishing belly fat for good!

References

  1. Vieira, A. F., Costa, R. R., Macedo, R. C. O., Coconcelli, L., & Kruel, L. F. M. (2016). Effects of aerobic exercise performed in fasted v. fed state on fat and carbohydrate metabolism in adults: a systematic review and meta-analysis. The British Journal of Nutrition, 116(7), 1153–1164. https://doi.org/10.1017/S0007114516003160
  2. Burke, L. M., Kiens, B., & Ivy, J. L. (2004). Carbohydrates and fat for training and recovery. Journal of Sports Sciences, 22(1), 15–30. https://doi.org/10.1080/0264041031000140527
  3. Ahlborg, G., & Felig, P. (1976). Influence of glucose ingestion on fuel-hormone response during prolonged exercise. Journal of Applied Physiology, 41(5 Pt. 1), 683–688. https://doi.org/10.1152/jappl.1976.41.5.683
  4. Horowitz, J. F., Mora-Rodriguez, R., Byerley, L. O., & Coyle, E. F. (1997). Lipolytic suppression following carbohydrate ingestion limits fat oxidation during exercise. The American Journal of Physiology, 273(4 Pt 1), E768-75.
  5. Lefkowitz, R. J. (1979). Direct binding studies of adrenergic receptors: biochemical, physiologic, and clinical implications. Annals of Internal Medicine, 91(3), 450–458.
  6. Strosberg AD. Structure, function, and regulation of adrenergic receptors. Protein Science : A Publication of the Protein Society. 1993;2(8):1198-1209.
  7. Manolopoulos, K. N., Karpe, F., & Frayn, K. N. (2012). Marked resistance of femoral adipose tissue blood flow and lipolysis to adrenaline in vivo. Diabetologia, 55(11), 3029–3037. https://doi.org/10.1007/s00125-012-2676-0
  8. Gjedsted, J., Gormsen, L. C., Nielsen, S., Schmitz, O., Djurhuus, C. B., Keiding, S., … Moller, N. (2007). Effects of a 3-day fast on regional lipid and glucose metabolism in human skeletal muscle and adipose tissue. Acta Physiologica (Oxford, England), 191(3), 205–216. https://doi.org/10.1111/j.1748-1716.2007.01740.x
  9. Hill, E. E., Zack, E., Battaglini, C., Viru, M., Viru, A., & Hackney, A. C. (2008). Exercise and circulating cortisol levels: the intensity threshold effect. Journal of Endocrinological Investigation, 31(7), 587–591. https://doi.org/10.1007/BF03345606
  10. Moyer, A. E., Rodin, J., Grilo, C. M., Cummings, N., Larson, L. M., & Rebuffe-Scrive, M. (1994). Stress-induced cortisol response and fat distribution in women. Obesity Research, 2(3), 255–262.
  11. Schoenfeld, B. J., Aragon, A. A., Wilborn, C. D., Krieger, J. W., & Sonmez, G. T. (2014). Body composition changes associated with fasted versus non-fasted aerobic exercise. Journal of the International Society of Sports Nutrition, 11(1), 54. https://doi.org/10.1186/s12970-014-0054-7
  12. Jeukendrup A. A Step Towards Personalized Sports Nutrition: Carbohydrate Intake During Exercise. Sports Medicine (Auckland, N.z). 2014;44(Suppl 1):25-33. doi:10.1007/s40279-014-0148-z.
  13. Paoli, A., Marcolin, G., Zonin, F., Neri, M., Sivieri, A., & Pacelli, Q. F. (2011). Exercising fasting or fed to enhance fat loss? Influence of food intake on respiratory ratio and excess postexercise oxygen consumption after a bout of endurance training. International Journal of Sport Nutrition and Exercise Metabolism, 21(1), 48–54.

How Nutrients Get Absorbed into Muscles

Building muscle requires a few important things:

  • Resistance-Training
  • Progressive Overload
  • High Protein Intake
  • Caloric Surplus
  • Plenty of Sleep

While each of these is important in their own right, all the sleeping, resistance training, and progressive overloading you do won’t do a lick of good if you’re not consuming a sufficient number of calories.

The way your body utilizes all of those calories is via the gastrointestinal (GI) system. It’s the foundation of muscle building, cognitive function, and overall health. The organs comprising your GI system work together to convert food into energy and the other essential nutrients required by the body.

But, how exactly do those nutrients make their way from your stomach to your muscles?

Let’s find out!

How is Food Digested

In order to understand how nutrients, get absorbed into your muscles, we first need to explain how food is digested in the body. The GI system includes your:

  • Mouth
  • Esophagus
  • Stomach
  • Liver
  • Pancreas
  • Gallbladder
  • Small Intestine
  • Large Intestine
  • Anus

Though we typically think of food being digested in the stomach, the process of digestion actually begins in the mouth. In fact, the mouth is responsible for mechanical and chemical digestion. Mechanical digestion is accomplished through the act of chewing, while chemical digestion is caused by the enzymes secreted by the salivary glands in saliva. But, saliva isn’t just for breaking down food, it also moistens food so it can work its way down your esophagus and into your stomach.

Upon entering the stomach, a mish-mash of enzymes and acids (hydrochloric acid) continue to break down food in addition to the stomach muscles that mix the food with these digestive juices. Not to be forgotten during digestion is the important role the liver, pancreas, and gallbladder serve. These three organs secrete the bile, digestive juices, and other important enzymes required to break down the wide variety of carbohydrates, fats, and proteins contained in the food you just ate.

After spending time in the stomach, the digested food is transported to your intestines, and it’s here where we start to see how nutrients get absorbed into your muscles.

From the GI System to Everywhere Else

Digestion is still occurring when your “food” (if you can still call it that by this point in the digestive process) reaches the small intestine. In fact, a large portion of the breakdown of complex carbohydrates (maltose, isomaltose, trisaccharides, larger oligosaccharides, etc.) still needs to be broken down into monosaccharides (simple sugars) so that they can be taken up. This brings us to the critical aspect of muscle-building — nutrient absorption.

The majority of nutrient absorption occurs in the small intestines and then directs them to your circulatory system for transportation to all the various parts of the body. Your blood is responsible for carrying simple sugars (monosaccharides like glucose), amino acids (the building blocks of protein), glycerol, and certain vitamins and salts to your liver. The liver either stores or processes and delivers the required nutrients where they are needed.

One of the most important component of nutrient absorption is the main anabolic hormone of the body — insulin. When glucose enters the blood, it stimulates the release of insulin — the primary nutrient shuttling in the body. Insulin picks up nutrients from your blood and drives them into your cells, your muscle cells in particular. Insulin is also tasked with shuttling amino acids and fatty acids into your cells as well. Upon entering the cell, glucose is converted to glycogen (the stored form of energy your muscles use for high-intensity exercise) while the amino acids get to work repairing damaged muscle tissue and building new muscle tissue.

Improving Nutrient Absorption

Consuming the right amounts of essential nutrients is crucial, but it won’t do much good if your body isn’t properly absorbing the nutrient you’re ingesting. You see, widespread use of antibiotics coupled with overconsumption of hyper-processed foods (i.e. chicken nuggets) has led to the decimation of good gut bacteria which is tasked with digestion and absorption of the essential nutrients your body requires for survival.

Fortunately, there are some ways you can enhance the number of good gut bacteria in your body and your body’s absorption of the nutrients you put into it on a daily basis.

  • Eat Plenty of Fiber

    Dietary fiber from fruits, vegetables, and whole grains provides the necessary “fuel” your gut bacteria need to keep functioning. Without this food, gut bacteria leach what they need from the lining of your GI tract which can lead to “leaky gut” and further nutrient absorption issues.

  • Chew Food Thoroughly

    Chewing plays a critical, and often underestimated, role in digestion. The more you chew, the more your food is broken down, which means there’s less work that needs to be done by the rest of your digestive system later on in the process. As an added bonus, chewing your food more thoroughly slows down how fast you’re eating, which gives your brain time to receive the signal that you are full, thereby preventing overheating.

  • Drink plenty of water

    Consuming enough water aids in the digestion and dissolution of fats and soluble fiber you eat, making for better nutrient absorption.

  • Exercise

    Exercise increases blood flow to your muscles (including those of the GI tract), but it also enhances blood flow to your organs. This is important because the walls of your colon need to contract when eliminated waste from the body, and exercise helps keep those muscles stimulated and active.

  • Drink less alcohol

    Whenever you consume alcohol, it disrupts acid secretion and digestion, leading to poor nutrient absorption. If you’re serious about losing fat and building muscle, you need to prioritize those essential muscle-building nutrients, which means passing on the alcohol, lest you not best use what you’re putting into your body.

  • Try probiotics

    Remember when we discussed the “good” gut bacteria above? Probiotics are one of the “good” bacteria in your gut that support immune system function. Probiotics compete for space in your gut with bad bacteria and can even help reduce the number of bad bacteria in your gut. Unfortunately, due to years of poor diets, most people are sadly lacking in probiotics.

    The remedy for this is to invest in some probiotic supplements or eat probiotic-rich foods (yogurt, kefir, sauerkraut, kombucha, etc.). This promotes the growth of more good gut bacteria, which can help ease IBS as well as combat allergies and the common cold.

References

  1. National Digestive Diseases Information Clearinghouse/National Institute of Diabetes and Digestive and Kidney Diseases. The Digestive System and How It Works
  2. Mourad FH, Saade NE. Neural regulation of intestinal nutrient absorption. Prog Neurobiol. 2011;95(2):149-162. doi:10.1016/j.pneurobio.2011.07.010.
  3. Goodman BE. Insights into digestion and absorption of major nutrients in humans. Adv Physiol Educ. 2010;34(2):44-53. doi:10.1152/advan.00094.2009.
  4. Desai MS, Seekatz AM, Koropatkin NM, et al. A Dietary Fiber-Deprived Gut Microbiota Degrades the Colonic Mucus Barrier and Enhances Pathogen Susceptibility. Cell. 2018;167(5):1339-1353.e21. doi:10.1016/j.cell.2016.10.043.
  5. Tracey J. Smith, Diane Rigassio-Radler, Robert Denmark, Timothy Haley, Riva Touger-Decker. Effect of Lactobacillus rhamnosus LGG® and Bifidobacterium animalis ssp. lactis BB-12® on health-related quality of life in college students affected by upper respiratory infections. British Journal of Nutrition, 2012; 1 DOI: 10.1017/S0007114512004138

Complete Guide to Evodiamine

Weight loss supplements, a.k.a. fat burners, are some of the most popular supplements on the market. Just about every company in the game has at least one product specifically designed to help you get lean, drop unwanted water weight, and reveal the slim, sexy physique hidden underneath the stored fat.

Most of you know that caffeine is one of the main ingredients in thermogenic fat burners, but have you given much thought about any of the other ingredients that are in your favorite weight loss product?

Probably not.

Today, we’re going to take a look at one of the less frequently used fat loss agents that helps crank up your thermogenic engine in evodiamine.

What is Evodiamine?

Evodiamine is a naturally occurring bioactive alkaloid from a plant called Evodia rutaecarpa. It has a long history of use in Traditional Chinese Medicine as a weight loss aid, where it goes by the name Wu-Chu-Yu. It’s also been used to treat various digestive problems including nausea, vomiting, diarrhea, stomach ulcers, and poor appetite. Evodiamine was also used by Chinese healers as a warming agent or “hot herb”, which speaks to its thermogenic properties.

The Evodia plant belongs to the Tetradium family of trees in Asia, but found predominantly in China, which explains its heavy use in ancient Chinese medicine.

What Does Evodiamine Do?

Evodiamine has been studied extensively, and researchers have documented a number of interesting effects the potent alkaloid exerts in the body.

Increases Body Temperature

The main reason you’ll see evodiamine used in supplements (particularly fat burners) is that it increases body temperature, which helps your body burn more calories and ultimately lose weight. Some research conducted on mice has shown that evodiamine may improve fat loss by 28% and decrease overall weight by 10%. [1]

Animal studies have also noted that evodia can improve resistance to cold, though this hasn’t been replicated in human trials yet. [1,2]

Anti-Obesity Effects

Evodiamine not only helps your body burn more calories, it also may prevent your body from creating new fat cells. Research has shown that evodiamine decreases preadipocyte differentiation.

What does that mean?

Basically, preadipocytes are “infant” fat cells that have to grow and mature into full-fledged adipocytes (fat). Growth and differentiation of preadipocytes are regulated by communication between individual cells or between cells and their external environment. Evodiamine is able to inhibit preadipocyte differentiation by disrupting these communication lines via two different mechanisms [3,4,5]:

  • Activates the MAPK cascade, subsequently reducing insulin-induced phosphorylation of Akt and PPARγ activity
  • Agonizes TRPV1 receptors (vanilloid receptors)

Through these actions, evodiamine reduces the uptake of fat and subsequently increases your body’s natural fat burning mechanisms. Burning more calories and preventing fat cells from maturing provides a two-pronged attack to help you get lean and mean!

Anti-Inflammatory

Over the counter non-steroidal anti-inflammatory drugs (NSAIDs) such as ibuprofen work by inhibiting a pro-inflammatory enzyme known as COX. Reducing inflammation helps reduce pain and swelling.

Aside from its warming and fat loss benefits, evodiamine was also used as a natural pain reliever, and there’s some research to support that use, as scientists have noted that evodiamine prevents upregulation of COX-2. [6] Moreover, the powerful alkaloid was shown to inhibit another well-known marker of inflammation in NF-kB.[6]

Stimulant Smoother

One of the most interesting things about evodiamine is that it can affect how your body metabolizes certain compounds, such as caffeine. More specifically, evodiamine reduces the exposure of caffeine to the body [7,8], which means it suppresses circulating levels of the stimulant and helps smooth out the stimulant effects of caffeine. Essentially, you get the energy and focus of caffeine, without the jitters or overstimulated feeling.

Some additional research indicates that evodiamine may also help improve cognition. [9]

Benefits of Evodiamine

  • Increases Thermogenesis
  • Relieves Pain
  • Decreases Inflammation
  • Enhances Fat Loss
  • Reduces Appetite

Evodiamine Dosing

Due to the lack of human studies on evodiamine, there hasn’t been an “ideal” or most effective dose; however, fat burners on the market dose it anywhere from 5-100mg, depending on the standardization of the evodia extract.

Now, as to effectiveness, evodiamine has an incredibly short half-life, lasting just under an hour. [11] Evodiamine also suffers from relatively low bioavailability, but the bioavailability can be improved when using a whole plant extract standardized for evodiamine rather than using an isolated evodiamine supplement.

Takeaway

Evodiamine is an underutilized fat burning agent that increases your calorie burn and prevents fat gain in the body. It may also suppress appetite and decrease pain and inflammation. When paired with caffeine, it helps smooth out the harsh “jolt” it can frequently provide, which is why you’ll see evodiamine frequently paired with caffeine in pre-workouts and fat burners.

References

  1.  Kobayashi, Y., Nakano, Y., Kizaki, M., Hoshikuma, K., Yokoo, Y., & Kamiya, T. (2001). Capsaicin-like anti-obese activities of evodiamine from fruits of Evodia rutaecarpa, a vanilloid receptor agonist. Planta Medica, 67(7), 628–633. https://doi.org/10.1055/s-2001-17353
  2. Callsen, M. G., Moller, A. T., Sorensen, K., Jensen, T. S., & Finnerup, N. B. (2008). Cold hyposensitivity after topical application of capsaicin in humans. Experimental Brain Research, 191(4), 447–452. https://doi.org/10.1007/s00221-008-1535-1
  3. Wang, T., Wang, Y., Kontani, Y., Kobayashi, Y., Sato, Y., Mori, N., & Yamashita, H. (2008). Evodiamine improves diet-induced obesity in a uncoupling protein-1-independent manner: involvement of antiadipogenic mechanism and extracellularly regulated kinase/mitogen-activated protein kinase signaling. Endocrinology, 149(1), 358–366. https://doi.org/10.1210/en.2007-0467
  4. Pearce, L. V, Petukhov, P. A., Szabo, T., Kedei, N., Bizik, F., Kozikowski, A. P., & Blumberg, P. M. (2004). Evodiamine functions as an agonist for the vanilloid receptor TRPV1. Organic & Biomolecular Chemistry, 2(16), 2281–2286. https://doi.org/10.1039/B404506H
  5. Zhang, L. L., Yan Liu, D., Ma, L. Q., Luo, Z. D., Cao, T. B., Zhong, J., … Tepel, M. (2007). Activation of transient receptor potential vanilloid type-1 channel prevents adipogenesis and obesity. Circulation Research, 100(7), 1063–1070. https://doi.org/10.1161/01.RES.0000262653.84850.8b
  6. Choi, Y. H., Shin, E. M., Kim, Y. S., Cai, X. F., Lee, J. J., & Kim, H. P. (2006). Anti-inflammatory principles from the fruits of Evodia rutaecarpa and their cellular action mechanisms. Archives of Pharmacal Research, 29(4), 293–297.
  7. Noh, K., Seo, Y. M., Lee, S. K., Bista, S. R., Kang, M. J., Jahng, Y., … Jeong, T. C. (2011). Effects of rutaecarpine on the metabolism and urinary excretion of caffeine in rats. Archives of Pharmacal Research, 34(1), 119–125. https://doi.org/10.1007/s12272-011-0114-3
  8. Tsai TH, Chang CH, Lin LC Effects of Evodia rutaecarpa and rutaecarpine on the pharmacokinetics of caffeine in rats . Planta Med. (2005)
  9. Yuan S, Gao K, Wang D, et al. Evodiamine improves cognitive abilities in SAMP8 and APPswe/PS1ΔE9 transgenic mouse models of Alzheimer’s disease. Acta Pharmacologica Sinica. 2011;32(3):295-302. doi:10.1038/aps.2010.230.
  10. Liao, J.-F., Chiou, W.-F., Shen, Y.-C., Wang, G.-J., & Chen, C.-F. (2011). Anti-inflammatory and anti-infectious effects of Evodia rutaecarpa (Wuzhuyu) and its major bioactive components. Chinese Medicine, 6(1), 6. https://doi.org/10.1186/1749-8546-6-6
  11. Hu CQ, Li F, Yang XW. Simultaneous determination and pharmacokinetic analysis of seven alkaloids and two flavonoids from rat plasma by HPLC-DAD after oral administration of Wuzhuyu decoction. J Asian Nat Prod Res. (2012)

Your Complete Guide to Sucralose

Sucralose is the leading artificial sweetener included in sports nutrition supplements these days. There’s a great deal of confusion about whether or not it’s safe for consumption or if it affects your blood sugar like regular sugar does. We’re here to answer all of your questions and more!

Sugar is public enemy #1.

It goes by countless aliases and can be found in all kinds of foods, from the obvious candy bars, cookies, and ice creams to the less obvious ketchup, yogurt, and salad dressings.

Sugar has been targeted for its role in the current obesity and diabetes dilemmas spanning the globe, and in the effort to curtail the ever-increasing health care crisis, food scientists developed an arsenal of alternatives to the conventional calorie-laden sweetener in non-nutritive sweeteners, a.k.a artificial sweeteners.

Chief among these zero-calorie sweetening alternatives is sucralose, better known by the trademarked name Splenda®. But, there’s been growing concern that these man-made sweeteners may be even more dangerous than sugar, bringing with it a host of problems more severe than an expanding waistline.

To help sort through confusion and disinformation, we’ve compiled this tell-all piece to explain what sucralose is, why it’s in your favorite supplements, and if you need to be concerned.

So, let’s start at the top….

What is Sucralose?

Sucralose (Splenda) is one of the most commonly used non-nutritive sweeteners on the market today. Other top alternatives to sugar include:

  • Stevia
  • Aspartame
  • Ace-K
  • Saccharin
  • Neotame
  • Monk Fruit (Luo Han Guo)

Sucralose is derived from sugar; however, in place of the 3 hydrocarbon groups attached to the carbon backbone are chlorine atoms. This molecular mish-mashing creates a molecule that is not recognized by your digestive system and passes through without being broken down and thus yielding no calories. Hence, sucralose being dubbed a “non-nutritive sweetener”.

Sucralose was discovered in 1976 by a British scientist who misheard instructions about testing a particular substance. Following the mishap, he tasted the “result” and found the new substance to be incredibly sweet.

Following the concerns of reports that aspartame caused cancer (which have since been proven false), sucralose skyrocketed to the forefront of the alternative sweetener line and it debuted in the United States in 1999 in the form of Splenda, which is a joint effort of the companies Johnson & Johnson and Tate & Lyle.

Splenda is frequently used as a substitute for sugar in baking and cooking and can be found in many sugar-free packaged goods these days.

Now, we need to make a small, but slightly important distinction before proceeding further. Sucralose in and of itself is calorie-free; however, Splenda (the little yellow packets you get at restaurants) is NOT calorie-free. Each packet of Splenda actually contains 3.36 calories per gram. [1] This is due to the fact that Splenda packets contain sucralose as well as dextrose and maltodextrin (two calorie-yielding carbohydrates).

Compared to standard sucrose (table sugar), sucralose is approximately 400-700 times sweeter than sugar, and one thing that separates sucralose from just about all other artificial sweeteners is that it doesn’t come with the unpleasant bitter aftertaste. [2,3]

Now, just because sucralose isn’t yielding any calories when you ingest it, doesn’t mean it’s completely inert when passing through your body. After all, when you consume sucralose it does have an extremely sweet taste, so, it stands to reason that it’s affecting some kind of receptor…. right?

Indeed, it does.

How Sucralose Works

Humans (and mice) have a “sweet” receptor called TAS1R3, which sucralose binds to in the body. [4] Other organisms do too! In flies, the sweet receptor is called Gr64a.[5] While it’s not really important that you know what receptor is stimulated by the ingestion of sucralose (or any other artificial sweetener for that matter), it is important to realize that just because something doesn’t yield calories does not mean it’s not affecting your body in some way, shape, or form.

Cellular biology out of the way, now we can begin to answer the question of whether or not sucralose presents any immediate concern.

Sucralose and Blood Sugar

The point of using non-nutritive sweeteners like sucralose is that they come with no calories (or very few) and don’t wreak havoc on blood sugar and insulin levels the way that regular table sugar does. However, due to the fact that sucralose does taste sweet and impact the sweet receptors in our body, it’s reasonable to think that sucralose might affect blood sugar levels.

So, what does the research say?

Well, remember, digestion begins in the mouth where our bodies secrete enzymes that start to “interact” and detect the food we eat and start to break it down. Under normal circumstances (i.e. eating regular sugar), these taste receptors sense sweet, setting off a chain of events that ends with the intestines detecting the sugar present and gleaning some calories (energy) from it. So, what happens when the body detects something but can’t get energy from it?

Well, one of two things…

One study conducted with individuals not accustomed to eating artificial sweeteners noted that ingesting sucralose before glucose can increase blood sugar and the body’s insulin response to carbohydrates. [9] However, after 12 weeks, there were NO significant differences between control and sucralose groups in terms of glucose regulation. In other words, the subjects using sucralose developed a “tolerance” of sorts.

Basically, researchers theorize that ingesting sucralose causes the body to create additional glucose transporters that deliver glucose from the gut to the body. However, this is only occurring in the short term, meaning that the increase in insulin and glucose uptake is only temporary until your body gets acclimated to “experiencing” sucralose in its system.

Sucralose and Appetite

Sucralose and the rest of the non-nutritive sweetening gang are frequently included in foods made to support weight loss efforts, due to the fact that they help reduce the total carb and calorie count of foods, but a common concern about artificial sweeteners is that they actually increase hunger levels.

So, by using sucralose are you “robbing Peter to pay Paul” in a sense…trading the reduced calories to increase hunger, which ultimately means you’re eating more?

Let’s see…

Research notes that sucralose may increase GLP-1 (glucose-dependent insulinotropic peptide) secretions when sucralose is consumed in the form of diet soda, but not when ingested on its own. [11,12] A separate study in mice noted ingestion of sucralose caused an increase in neuropeptide Y, a powerful hunger-stimulating protein. [5]

While this might be a bit off-putting, remember, these studies were conducted in non-human populations. The results of these studies DO NOT translate directly to human metabolism.

Ok, so, are there any human studies assessing sucralose and appetite?

Indeed, there are, and here’s what they found:

Human research found that sucralose does NOT increase appetite, consumed either in the form of diet soda or on its own. [11,13,14] In fact, researchers compared the effects of sucralose on appetite to that of water.

Bottom line — sucralose doesn’t make you hungrier.

Regarding weight gain, studies on the weight loss/gain effects of non-nutritive sweeteners are mostly correlational and the few double-blind trials that have been run, along with the meta-analyses reviewing everything compiled on the weight implications of non-nutritive sweeteners indicate they have no effect on fat mass or lead to mild weight loss. [15]

Sucralose and Your Gut

A few years back, sucralose came under fire when some rodent research documented that ingestion of the non-nutritive sweetener increased the rat’s risk for irritable bowel diseases [6], though some researchers suspect this is more likely attributed to a low fiber intake than the artificial sweeteners.

Other research in mice noted sucralose led to the development of symptoms associated with Crohn’s disease and liver inflammation. [7,8] However, these studies noted that the effects were dependent on the gut bacteria present on the mice, not the interactions with the rodents’ “sweet receptor.”

In particular, the study noting liver inflammation showed a change in the intestinal bacteria towards strains that were pro-inflammatory (i.e. “bad” bacteria) whereas the Crohn’s study noted an increase in oxidation generated by the gut bacteria.

While this might be fodder for the fearmongering folks in the media, there’s a couple things to remember about these studies:

  1. They’re conducted in rats. It’s nigh-impossible to extrapolate what would happen to humans. We barely have a grasp on our own metabolism, much less the intricacies of our gut bacteria. It might be that the gut bacteria themselves have sweet receptors and get a bit angry when they’re tricked by these “fake sugars.”
  2. The animals used in the studies consumed an extremely poor diet, and it’s simply not logical to assume that what occurs in their gut microbiome will carry over into a human gut, especially if one is consuming a diverse diet rich in micronutrients.

Is Sucralose Safe?

To date, science has not conclusively shown that sucralose presents any immediate danger or concern with consuming it on a regular basis. Additionally, it’s also be designated GRAS (generally recognized as safe) by the FDA.

There are some animal studies showing it can alter gut bacteria, but nothing conclusive has been proven one way or another in human trials. Also, while sucralose may have a very short-term effect on glucose and insulin secretions, the effects do not appear to be long-lasting, and there’s also no evidence that sucralose adversely impacts weight or hunger levels in humans.

Given the drove of consequences that come with excess sugar consumption, having an alternative that doesn’t provide a way to enjoy sweet food fare without having to worry about blowing your diet or messing with your insulin levels.

All things considered, sucralose is recognized as safe for consumption and when stacked up against the other sweetening options available seems to be a fairly safe bet. If you’re concerned about any GI issues from using sucralose, make sure to consume moderately and always maintain a micronutrient-dense diet full of whole foods.

References

  1. https://ndb.nal.usda.gov/ndb/search
  2. WIET, S. G. and BEYTS, P. K. (1992), Sensory Characteristics of Sucralose and other High Intensity Sweeteners. Journal of Food Science, 57: 1014-1019. doi:10.1111/j.1365-2621.1992.tb14345.x
  3. Horne J, Lawless HT, Speirs W, Sposato D. Bitter taste of saccharin and acesulfame-K. Chem Senses. 2002;27(1):31-38.
  4. Harrington EO, Vang A, Braza J, Shil A, Chichger H. Activation of the sweet taste receptor, T1R3, by the artificial sweetener sucralose regulates the pulmonary endothelium. American Journal of Physiology – Lung Cellular and Molecular Physiology. 2018;314(1):L165-L176. doi:10.1152/ajplung.00490.2016.
  5. Wang Q-P, Lin YQ, Zhang L, et al. Sucralose Promotes Food Intake through NPY and a Neuronal Fasting Response. Cell Metab. 2016;24(1):75-90. doi:10.1016/j.cmet.2016.06.010
  6. Sakamoto N, Kono S, Wakai K, et al. Dietary risk factors for inflammatory bowel disease: a multicenter case-control study in Japan. Inflamm Bowel Dis. 2005;11(2):154-163.
  7. Rodriguez-Palacios A, Harding A, Menghini P, et al. The Artificial Sweetener Splenda Promotes Gut Proteobacteria, Dysbiosis, and Myeloperoxidase Reactivity in Crohn’s Disease-Like Ileitis. Inflamm Bowel Dis. 2018;24(5):1005-1020. doi:10.1093/ibd/izy060
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