New "Lean Gains" Study Confirms: IF Gets Athletes Lean & Improves Insulin Sensitivity W/Out Impairing Their Gains

Intermittent fasting has accumulated lots of scientific back-up in obese subjects and rodent models of obesity. In lean, athletic folks, however, the "evidence" is - with one exception - based on hear-say and N=1 reports... until now!

While previous studies in Ramadan fasting have already provided some evidence of the efficacy of intermittent fasting - lean gains style - aka 16h fasting to 8h feeding, the latest study from the University of Padova is the latest of two studies (here's a write-up of the other one) that were specifically designed to evaluate the efficacy of what the scientists call "an increasingly popular dietary approach used for weight loss and overall health" (Moro. 2016).

As the authors likewise point out, the evidence that intermittent fasting (IF) can have significant beneficial effects on blood lipids and other health outcomes in the overweight and obese, albeit mostly using alternate day fasting (learn more), there's limited about the effect of IF in athletes.

Do you have to worry about fasting when you're dieting!?

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Breakfast? (Un?) Biased Review

Trained individuals such as the thirty-four resistance-trained males (age 29.21 ± 3.8; weight 84.6 ± 6.2 kg) who were randomly assigned to time-restricted feeding (TRF) or normal diet group (ND) in the latest study from the University of Padova.

"The criteria for entering the study were that subjects must have performed resistance training continuously for at least 5 years (training 3–5 days/week with at least 3 years experience in split training routines), be presently engaged in regular resistance training at the time of recruitment, be life-long steroid free, and have no clinical problems that could be aggravated by the study procedures" (Moro. 2016).

Time restrictedly fed (TRF) subjects consumed 100 % of their energy needs in an 8-h period of time each day, with their caloric intake divided into three meals consumed at 1 p.m., 4 p.m., and 8 p.m. The remaining 16 h per 24-h period made up the fasting period.

Figure 1: Diet composition and macronutrients distribution at basal level and during the experimental period in both groups as assessed by 7-day food questionnaires (Moro. 2016).

And yes, this means that they consumed the same energy-sufficient diet (on paper as well as according to 7-day food questionnaires) as the subjects in the normal diet group (ND).

"The distribution of calories was 40, 25, and 35 % at 1 p.m., 4 p.m. and 8 p.m. respectively for TRF, while ND subjects consumed 25, 40 and 35 % of daily calories at 8 a.m., 1 p.m. and 8 p.m. respectively. The specific calorie distribution was assigned by a nutritionist and was based on the reported daily intake of each subject" (Moro. 2016) 

What is also important to know is that no snacks between the meals were allowed except 20 g of whey proteins 30 min after each training session. Every week, subjects were contacted by a dietician in order to check the adherence to the diet protocol. The dietician performed a structured interview about meal timing and composition to obtain this information (results see Figure 1) and the exercise part was standardized for both groups, and all subjects had at least 5 years of continuous resistance training experience prior to the study. Training consisted of 3 weekly sessions performed on non-consecutive days for 8 weeks.

Figure 2: Changes in body composition and strength from pre- to post-study (Moro. 2016).

And the results of the scientists' body comp and strength analyses show that "intermittent fasting" was not to the disadvantage of the subjects. Rather than that, the N = 17 subjects in the ND group saw the same fat loss benefits almost always who's adhering to an intermittent fasting regimen reports and didn't have their muscle or strength gains compromised. Things that did change, however, were ...

• total testosterone and IGF-1 which decreased significantly in TRF after 8 weeks while no significant differences were detected in ND,
• blood glucose and insulin levels which decreased significantly only in TRF subjects and conformingly a significant improvement of HOMA-IR was detected,
• adiponectin which increased, leptin which decreased (but this was not significant when normalized for fat mass), and 
• thyroid hormone T3 which decreased significantly compared to ND, without any significant changes in TSH
• TNF-α and IL-1β, two markers of inflammation, which were lower in TRF at the conclusion of the study as compared to ND
• respiratory ratio (RER) which was lowered in the TRF group indicating a relative increase in of fat (at the expense of carbohydrates) to fuel the subjects' energetic demands; demands that stayed 1:1 identical in both groups.

In view of the results of previous studies in obese individuals, it may be a bit surprising, though, that there were no significant changes were detectable for lipids (total cholesterol, HDL-c, and LDL-c), except for a decrease of triglycerides in TRF group.

Read my elaborations on the other "IF + exercise study" that showed benefits during cuts, as well | here

Bottom line: As the authors rightly point out, what is new about their study is that they took measures to avoid intermittent-fasting-induced energy deficits that would provide a non-timing related explanation for the significant loss of body fat the authors observed in this recent 8-week study.

Yes, you can still argue that the subjects may have been misreporting extra-intakes such as snacks because they were not supposed to eat them. Sure, ... but let's assume at least for the time being that the fat loss was not a result of reduced food intake. What else could it be, then?

Well, as Moro et al. point out candidates include the "increase of adiponectin that interacts with adenosine 5′-monophosphate-activated protein kinase (AMPK) and stimulates Peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PGC-1α) protein expression and mitochondrial biogenesis" (Moro. 2016). Adiponectin has also been shown to act in the brain to increase energy expenditure and cause weight loss (Gulcelik. 2013). In that, adiponectin is also the better candidate than leptin which did not change significantly when it was normalized for the subjects' fat mass.

Somewhat related, but eventually different is Moro's hypothesis that the fasting enhanced the subjects' thermogenic response to epinephrine and/or an increase in REE - a thesis with which the authors went into the study, but realized that it was not confirmed by their results | Comment!

References:

• Gulcelik, N. E., et al. "Adipocytokines and aging: adiponectin and leptin." Minerva endocrinologica 38.2 (2013): 203-210.
• Moro, Tatiana, et al. "Effects of eight weeks of time-restricted feeding (16/8) on basal metabolism, maximal strength, body composition, inflammation, and cardiovascular risk factors in resistance-trained males." Journal of Translational Medicine 14.1 (2016): 290.

35g of PWO Whey Don't Build Extra Muscle, but Help Shed Body Fat | Plus: Is Hydro-Whey Better Than Concentrate?

Bad news bro: Whey will shed significant amounts of trunk and android fat only in conjunction with 16 weeks of resistance training. No matter what the ads promise.

Ok, Hulmi's 2015 study into the effects of protein / protein + carbohydrate supplementation that was consumed after each of the workouts in a 12-week resistance training protocol is not exactly "the latest science", but the results are still interesting and provide some insights into the importance of irrelevance of post-workout nutrition.

Why's that? With different training protocols focusing on strength endurance and strength-hypertrophy-power, and three supplementation groups with either protein (37.5g whey concentrate), carbohydrate (34.5g maltodextrin) or a combination of both, whey and maltodextrin.

Read more about ISSN studies like Hulmi's at the SuppVersity

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All subjects were mixed with non-caloric sugar-free drinks (FUN Light provided by Orkla Foods Finland, Turku, Finland) depending on the week and subject’s preference (either strawberry,
forest fruit, pomegranate-strawberry, apple-pear or raspberry-lemon).

Otherwise, the subjects were advised to eat normal recommended mixed meal based on the Finnish
Nutrition Recommendations 2014 (see below) 1–2 hours after the exercise bout.

Download the >600 page NNR2012 for free.

"Subjects kept 4-day food diaries during the second block of the 12-week RT period. Dietary intake was recorded over three weekdays and one weekend day [not ideal, but better than nothing].

The researchers gave subjects both verbal and written nutritional recommendations based on the Finnish Nutrition Recommendations 2014. As a rule, these follow the recommendations for the Nordic countries in Europe pub lished in Autumn 2013 (NNR2012) and are very close to USDA and HHS dietary guidelines (2010) for normal healthy adults. The subjects were instructed on how to report nutritional intake in the diaries.

Nutrients provided by the supplements were included in the analysis. The food diaries were analyzed by nutrient analysis software (Nutri-Flow; Flow-team Oy, Oulu, Finland)" (Hulmi. 2015).

In combination with the workout routine outlined in Tables 1 & 2, the dietary + supplement intervention lead to significant increased fat-free mass, muscle size and strength and that independent of post-exercise nutrient intake (P < 0.05).

Table 1 & 2: An overview of the RT program: the first block was a preparatory phase after which supplementations started and within those the subjects were separated into 2 different training regimens. Training bout consisted always of four main exercises trained with the specific regimen of using either MS, HS or PS as a focus. Five accessory exercises were trained in an HS manner // Typical exercise bout performed 2–3 x week contained exercises for legs, whereas exercises for other muscle groups rotated and thus were trained on average once per week (Hulmi. 2015).

What a closer look at Figure 1 and thus the actual changes in body fat, muscle size and strength can tell you, however, is that the whey protein wasn't "ineffective", at all.

Body composition changes in Lockwood et al. (top | 2016) and effects of adding small amounts of hydro whey on anti-oxidant activity of a lemon whey beverage (bottom | Athira. 2015).

Concentrate or hydrolysate - For fat loss, the latest study suggests the latter: Even though Hulmi et al. have used a "cheap" (and tasty) whey concentrate, another, more recent study by Lockwood et al. (2016) showed a significant loss of body fat only in the whey hydrolysate group - even though the muscle gains in response to 2x30g of the whey concentrate (WPC), and the high lactoferrin containing whey concentrate (WPC-L) were identical over the 8-week resistance training study.

How come? I guess there are a few potential reasons here, all of which eventually relate to the peculiar (small) peptide structure of the practically pre-digested whey protein. One being the peptides' glutathione boosting anti-oxidant prowess, which is way greater for hydrolysates vs. concentrates (Pacheco. 2005). It could also be the peptides ACE-inhibitory activity (Tavares. 2011; Sawada. 2016), which has been linked to fat loss in rodent studies (Weisinger. 2009) and preliminary evidence of improvements in body composition in human studies (Carter. 2005). As well as evidence of its ability to improve glucose management (Adams. 2016).

After all, the whey group saw significantly more pronounced total and abdominal area fat when compared to the carbohydrate group - and that was the case for both, the high(er) energy demand SHP and the low(er) energy demand HS training (P < 0.05).

Figure 1: Changes in body fat (top), and performance measures (bottom); green = there are stat. significant inter-group differences; grey = there are no stat. sign. inter-group differences (Hulmi. 2015).

If we talk body composition (which was assessed by Dual-energy X-ray absorptiometry, DXA) it is also worth pointing out that the administration of whey protein after the workouts lead to a larger relative increase (per kg body weight) in fat-free mass compared to the protein vs. carbohydrate group (P < 0.05) - albeit without significant differences between the combined group.

Figure 2: If you're still thinking about the concentrate vs. hydrolysate study, here are some hints on what may contribute to the difference Lockwood et al. have reported only recently (Lockwood. 2016).

No systematic effects of the interventions were found for serum lipids. The same goes for the changes in maximal voluntary contraction (even though, carbs appear to have some sort of benefit, here), the actual muscle size as measured as cross-sectional area (CSA) and the 1RM maximal leg strength.

So, why do many "experts" still emphasize the importance of post-workout carbohydrates? Well, I guess a good answer (not sure all of them can give you one, though) would be the possibility to increase your training frequency from frequent to extremely frequent without compro-mising your performance on the altar of low(er) carb intakes, because you're afraid of fat gains due to the insulin boogieman.

You believe you are training "extremely frequently"? I doubt that. - or do you hit the gym, the road or the pool twice or thrice a day, with every workout lasting (several) hours? No, ok, then you better don't eat like Michael Phelps does and this goes for both, his energy and macronutrient intake... unless, obviously, you want to balloon up like a porker.

If, on the other hand, you are one of the few pro-athletes that burn through 5,000-8,000 kcal on a daily basis, you will be having a hard time getting enough energy to perform without a high carbohydrate intake (and for many athletes carbohydrate supplements in form of energy drinks, gels and bars).

So, whey helps, CHOs don't. Great, but there is a few question we still have to address: (1) Do dietary differences explain the whey advantage? Meaning: Did the subjects simply get more protein, consume fewer calories or have any other "unique" dietary quality, besides the 30g+ of whey protein PWO?

If statistical significance is our yardstick, the answer is no. If it's absolute differences between mean intakes, however, the whey and whey + CHO group consumed 15 and 16% fewer calories, respectively. Can that explain a fat loss of 1.5 kg? Well, mathematically it can, because that's a 438kcal difference in favor of the whey groups. If we did the math and assumed that 16 weeks on a pseudo-deficit of 438kcal per day should translate into 7 kg of body fat loss... besides being based on the stupid 7000kcal per 1kg of body fat equation, this prediction does yet have another problem. With almost identical energy intakes in the two whey groups, i.e. whey along and whey + CHO, the fat loss should be identical. That this is not the case clearly refutes the notion that it's only about calories. It's also not just about protein, because the total protein intake (including supplements) of the CHO group was higher not lower than in the whey groups.

(2) Would a no-carb control have shown a similar lack of body fat loss? Meaning: Did the extra carbohydrates blunt the fat loss, or did the whey accelerate it?

This is likewise a question that cannot be answered conclusively without a follow-up trial, but with sign. fat loss in the whey + CHO group and no fat loss in the CHO group (receiving the same amount of carbs), we can pretty much exclude the possibility that the carbs are to blame. The answer to the above question is thus probably that whey accelerated the fat loss, just as it did in Antonio (2014), where a very high protein intake (3.4g/kg) that was achieved by the means of whey or beef protein supplements helped the subjects of the 8-week study shed an average of 1.6 kg of fat mass (compared to only 0.3 kg in the high protein group, ingesting only 2.3g/kg from foods) | Comment on Facebook!

References:

• Adams, R. L., and K. S. Broughton. "Insulinotropic Effects of Whey: Mechanisms of Action, Recent Clinical Trials, and Clinical Applications." Annals of Nutrition and Metabolism 69.1 (2016): 56-63.
• Athira, Syamala, et al. "Production and characterisation of whey protein hydrolysate having antioxidant activity from cheese whey." Journal of the Science of Food and Agriculture 95.14 (2015): 2908-2915.
• Carter, Christy S., et al. "Angiotensin-converting enzyme inhibition intervention in elderly persons: effects on body composition and physical performance." The Journals of Gerontology Series A: Biological Sciences and Medical Sciences 60.11 (2005): 1437-1446.
• Lockwood, Christopher M., et al. "Effects of Hydrolyzed Whey versus Other Whey Protein Supplements on the Physiological Response to 8 Weeks of Resistance Exercise in College-Aged Males." Journal of the American College of Nutrition (2016): 1-12.
• Pacheco, Maria Teresa Bertoldo, and Valdemiro Carlos Sgarbieri. "Effect of different hydrolysates of whey protein on hepatic glutathione content in mice." Journal of medicinal food 8.3 (2005): 337-342.
• Sawada, Yoko, et al. "Milk‐derived peptide Val‐Pro‐Pro (VPP) inhibits obesity‐induced adipose inflammation via an angiotensin‐converting enzyme (ACE) dependent cascade." Molecular nutrition & food research 59.12 (2015): 2502-2510.
• Tavares, Tânia, et al. "Novel whey-derived peptides with inhibitory effect against angiotensin-converting enzyme: in vitro effect and stability to gastrointestinal enzymes." Peptides 32.5 (2011): 1013-1019.
• Weisinger, Richard S., et al. "Angiotensin converting enzyme inhibition lowers body weight and improves glucose tolerance in C57BL/6J mice maintained on a high fat diet." Physiology & behavior 98.1 (2009): 192-197.

Cycling Only 10 Min After Workouts Promotes Recovery as Effectively, Cheaper and More Conveniently Than Ice Baths

Active recovery in the form of light intensity exercise, such as walking or cycling on a cycle ergometer may be suitable for every exercise modality and is not more or less effective than the much fancier but rareley available cold water immersion therapy

Cold water immersion and active recovery are common post-exercise recovery treatments you've read about before at the SuppVersity. With the publication of the latest study from the Queensland University of Technology, this is yet the first article to discuss a comparison of both recovery methods in a nine trained male individuals - a study that shows "that cold water immersion is no more effective than active recovery for minimizing the inflammatory and stress responses in muscle after resistance exercise" (Peake. 2016).

Just like the previously reported anti-adaptive effects of ice-baths (yes, they will impair your gains | learn more), the study at hand adds to the accumulating evidence that cold water immersion, one of the most commonly used post-workout recovery strategies, is everything but a gold standard.

Hormesis is why soothing the inflammation is not always good for athletism

Is Vitamin E Good for the Sedentary Slob, Only?

Even Ice-Baths Impair the Adapt. Process

Vit C+E Impair Muscle Gains in Older Men

C+E Useless or Detrimental for Healthy People

Vitamin C and Glucose Management?

Antiox. & Health Benefits Don't Correlate

But how do Peake et al. know that? Well, the researchers compared the effects of cold water immersion versus active recovery on inflammatory cells, pro-inflammatory cytokines, neurotrophins and heat shock proteins (HSPs) in skeletal muscle after a standardized intense resistance exercise.

"The resistance training sessions for the two experimental trials were identical and involved single-leg exercises such as 45° leg press (six sets of 8–12 repetitions), single-leg squats (three sets of 12 repetitions), knee extensions (six sets of 8–12 repetitions), and walking lunges (three sets of 12 repetitions). The total duration of the session was ~45 min" (Peake. 2016).

Five minutes after the workout, the subjects either jumped into an inflatable (ice-)bath (iCool iBody, iCool, Miami, Australia) for 10 min (both legs immersed in water up to the waist) or they performed 10 min of active recovery at a self-selected low intensity (on average a meager 36.6 ± 13.8 W) on a stationary cycle ergometer (Wattbike, Nottingham, UK).

Figure 1: Post-exercise changes in CD66b+ neutrophil infiltration, CD68+ macrophage infiltration, and MAC1 and CD163 mRNA expression. Data are presented as the change in the median +/- interquartile range for neutrophils and CD163 mRNA, and the geometric mean +/- 95% confidence interval for macrophages and MAC1 mRNA. ACT, active recovery; CWI, cold water immersion. n = 9. * P < 0.05 versus pre-exercise value (Peake. 2016).

Muscle biopsies were collected from the exercised leg before, 2, 24, and 48 h after
exercise in both trial to access the intramuscular neutrophil and macrophage counts, as well as the inflammatory markers MAC1 and CD163 mRNA, IL1, TNF, IL6, CCL2, CCL4, CXCL2, IL8 and LIF mRNA expression (P<0.05); and the analysis of this data, as well as creatine kinase, subjective feelings of hyperalgesia, the expression of NGF and GDNF mRNA and the levels of B-crystallin and HSP70 showed no difference between the two recovery treatments.

Even simple compression socks will cost you $25+ If you want a complete "compression suit" consisting of shirt, tights, and more, you will probably have to spend roughly $200. Against that background you may be happy to hear that there's some scientific backup that the money you spend could not be wasted.

Compression garments - do they help? No, they usually don't look sexy, but they are the latest craze among recovery modalities. The question whether they just sell, or even work, has now been addressed in a systematic review with meta-analysis by Marqués-Jiménez (2016); a paper that found "conclusive evidence increasing power and strength", "conclusive evidence reducing perceived muscle soreness and swelling" but "no clear evidence of decreased lactate or creatine kinase" and "little evidence of decreased lactate dehydrogenase". Overall, the existing evidence does therefore suggest that "the application of compression clothing may aid in the recovery of exercise induced muscle damage, although the findings need corroboration" (Marqués-Jiménez. 2016).

I guess, that's, figuratively speaking, an accolade for the simplest recovery technique there is: low(est) intensity exercise, a recovery modality of which previous studies have shown that it will (a) significantly reduce your blood lactate concentration after various activities (Rontoyannis. 1988) and (b) increase your performance after workouts such as the parallel squat workout in a Y2k study by Corder et al. (2000), the HIIT workout in Connolly, et al. (2003), the supra-maximal exercise tests in Spierer, et al (2004 | see Figure 2), the swimming protocols in Toubekis' 2008 study, or the 2007 resistance training study by Anna Mika et al. who concluded that "the most appropriate and effective recovery mode after dynamic muscle fatigue involves light, active exercises, such as cycling with minimal resistance" (Mika. 2007).

Figure 2: The 2004 study by Spierer et al. is also interesting, because it shows that the benefits of active recovery on the performance and perceived fatigue after supra-maximal exercise tests may vary according to the training status of the study subjects; with less trained or simply sedentary subjects benefitting more (Spierer. 2004).

Now, Peake et al. are certainly right, when they point out that their "findings indicate that cold water immersion is no more effective than active recovery for reducing inflammation or cellular stress in muscle after a bout of resistance exercise," there's one thing that will have to be done in the future: a comparison of active vs. ice-tub recovery on the longitudinal adaptational response (VO2max, power, strength, hypertrophy) to various training modalities. After all, any modulation of the post-exercise inflammatory response, be it via cold water immersion or light exercise, could exert detrimental effects on your "gainz" (in the broadest sense of the word) - the only pertinent study by Yamagashi, however, shows that this is not the case and using an active recovery protocol at 40% of V̇O2peak significantly enhances, not impairs, the endurance adaptations to HIT (Yamagashi. 2016).

SuppVersity Classic: "Cupping for Pain, Health & Performance | Must Be Good, if Phelps Does it, Right? Let's See What the 100+ Studies Say" - The "cups" come in various forms and sizes... and no, there's no meta-analysis yet that can tell you what the optimal size and form for the treatment of a given problem would be | more

Bottom line: If you've been thinking about buying an ice tub, forget it. There's, as Anthony Barnett pointed out in his 2006 review, a profound lack of evidence of positive effects of current recovery modalities such as massage therapy, contrast temperature water immersion, hyperbaric oxygen therapy (HBOT), stretching and EMS. Eventually, the time and money you spend on any of them between your workouts may thus be wasted - plus: a simple 10-minute ergometer ride at an extremely low exercise intensity can likely do the same as any of the en-vogue but costly recovery techniques, devices and modalities.

With the recently published PhD study by Yamagashi, there's also initial evidence that active recovery strategies won't, as it has been shown for ice baths, impair the adaptational VO2max response to high-intensity exercise...

Whether that's also the case for resistance training and the corresponding training goals hypertrophy and strength, however, will have to be elucidated in future long(er)-term studies in trained and untrained individuals | Comment on Facebook!

References:

• Barnett, Anthony. "Using recovery modalities between training sessions in elite athletes." Sports medicine 36.9 (2006): 781-796.
• Connolly, Declan AJ, Kevin M. Brennan, and Christie D. Lauzon. "Effects of active versus passive recovery on power output during repeated bouts of short term, high intensity exercise." J Sports Sci Med 2.2 (2003): 47-51.
• Corder, Keith P., et al. "Effects of Active and Passive Recovery Conditions on Blood Lactate, Rating of Perceived Exertion, and Performance During Resistance Exercise." The Journal of Strength & Conditioning Research 14.2 (2000): 151-156.
• Marqués-Jiménez, Diego, et al. "Are compression garments effective for the recovery of exercise-induced muscle damage? A systematic review with meta-analysis." Physiology & behavior 153 (2016): 133-148.
• Mika, Anna, et al. "Comparison of recovery strategies on muscle performance after fatiguing exercise." American journal of physical medicine & rehabilitation 86.6 (2007): 474-481.
• Peake, Jonathan M., et al. "The effects of cold water immersion and active recovery on inflammation and cell stress responses in human skeletal muscle after resistance exercise." The Journal of Physiology (2016).
• Rontoyannis, George P. "Lactate elimination from the blood during active recovery." Journal of sports medicine and physical fitness 28.2 (1988): 115-123.
• Spierer, D. K., et al. "Effects of active vs. passive recovery on work performed during serial supramaximal exercise tests." International journal of sports medicine 25.02 (2004): 109-114.
• Toubekis, Argyris G., et al. "Swimming performance after passive and active recovery of various durations." Int J Sports Physiol Perform 3.3 (2008): 375-386.
• Yamagishi, Takaki. "Role of active and passive recovery in adaptations to high intensity training." (2016).

Latest Study Shows that a 3.3 g/kg High-Protein Diet is Safe -- And Yes, This Means it Doesn't Hurt Your Kidney or Liver

Don't forget that meat and dairy are not the only good sources of protein in your diet. In fact, even vegan athletes can - albeit with some effort - follow a diet that's so high in protein that traditionalists would say it may put your kidney and liver on the line - plant protein, or not...

Guest post by Alex Leaf (leaf-nutrition.com) - There is a pervasive myth among vegans and health professionals alike that a high-protein diet is harmful, particularly for the kidneys. This is despite the World Health Organization official report on protein stating that "the most widely quoted potential problems relate to renal function and damage, but as discus-sed above the evidence for such claims in otherwise healthy individuals does not stand up to scrutiny" (WHO. 2016).

Still, the vast majority of protein safety data that we have is with intakes less than 2.0 g/kg bodyweight. And for most people, that is all the data we need, because most people don’t eat more than their weight in grams of protein. But there are exceptions, with the biggest probably being athletes.

High-protein diets are much safer than pseudo-experts say, but there are things to consider...

Practical Protein Oxidation 101

5x More Than the FDA Allows!

More Protein ≠ More Satiety

Protein Oxidation = Health Threat

Protein Timing DOES Matter!

More Protein = More Liver Fat?

It is very common for athletes to eat more than 2.0 g/kg of protein in attempts to maximize performance and/or body composition. Two previous studies by Dr. Jose Antonio have suggested that eating a high-protein diet (>3.0 g/kg) has no harmful side-effects over the 8-week intervention periods (Antonio. 2015 & 2016a). However, we still lack long-term data on high-protein diet safety. Or I should say, we did lack this data until Dr. Antonio published his fourth study this week in the Journal of Nutrition and Metabolism (Antonio. 2016b).

Figure 1: Comparison of habitual and experimental diet of the subjects (Antonio. 2016).

In Dr. Antonio’s latest study, 14 resistance-trained men consumed their habitual diet or a high-protein diet each for a two-month and a four-month period (six months total spent on each diet). The extra protein on the high-protein diet phase was supplied mainly from whey protein, although the participants were allowed to eat whatever they wanted to hit their protein quota.

What's a guest post and who's Alex Leaf? Many of you will already know that Alex Leaf is a good friend of mine, who has recently turned his passion for nutrition, training and supplementation into a profession and opened his own business, Leaf Nutrition - obviously not before amassing a range of titles from certified personal trainer to the Master of Nutrition and certifications as nutritionist from the state of Washington and the International Society of Sports Nutrition. Future coaching requests should thus better go to Alex than me, after all, he has the time, the education and the patience to work with clients I have never had (those of you who asked me if I do coaching will know that).

Food intake was monitored with the smartphone app, MyFitnessPal, for which all the participants had experience using, and each participant followed their own strength training program.

As we can see in Figure 1 above, the men were already consuming a relatively high protein diet, with a habitual intake of 2.5 g/kg. Yet, this significantly increased to 3.3 g/kg during the high-protein phase, leading to a significant 16% increase in caloric intake. Carbohydrate, fat, cholesterol, sodium, sugar, and fiber intake were not significantly different between phases. There were no significant differences between the habitual and high-protein groups in any measure of health or body composition, including blood lipids and a comprehensive metabolic panel (renal function, liver health, etc.).

Putting the results into perspective

One thing you should remember about the study at hand is that its subjects were athletes. As you may remember from the article "The Insulin / Glucagon Ratio and Why Diabetics and People W/ Severe Insulin Resistance Must be Careful With Protein" (read it) that the results could be very different for (obese) T2DM patients.

This is the first randomized controlled trial that has examined the effects of a high protein diet in resistance-trained men over a one-year period. Aside from the countless anecdotal evidence, this is the best evidence we currently have to suggest that consuming 3-4 times the RDA is safe in athletes.

Now, we could nit-pick and say that the sample size was too small and that the study is applicable only to male athletes, or even that one year isn’t long enough considering that chronic kidney disease can take years to decades to develop. And these are valid arguments. However, other populations outside of individuals regularly exercising are not likely to be interested in consuming this level of protein, nor would they need to, so the need to apply this data to other populations may be a moot point.

As for the length of the study, we must consider this alongside the fact that athletes have been eating this level of protein for most of their lives and are healthier than people eating less protein. Although anecdotal evidence isn’t ideal, it isn’t worthless either, especially when it exists in the vast quantities that we observe with the athletic population.

Antonio et al. are only one group of researchers dabbling w/ the health and physique advantage of really high protein diets | more.

So what is the practical takeaway? Eating up to 3.3 g/kg or 1.5 g/kg of protein appears to be safe so long as you are training regularly and have a relatively healthy, well-balanced diet providing adequate fiber (30 g average in this study | previous studies show links of high fiber intakes w/ kidney and liver health | Xu. 2014, Kirpich. 2015, Arslanow. 2016).

And even if "young, healthy and active" doesn't sound like you, there are studies like Brinkworth (2004), Clifton (2008), and Dumesnil (2001) that show weight loss benefits and identical or improved health parameters compared to "regular" / lower protein diets | Comment on Facebook!

References:

• Antonio J, Ellerbroek A, Silver T, et al. A high protein diet (3.4 g/kg/d) combined with a heavy resistance training program improves body composition in healthy trained men and women--a follow-up investigation. J Int Soc Sports Nutr. 2015; 12: 39. PMID: 26500462
• Antonio J, Ellerbroek A, Silver T, Vargas L, Peacock C. The effects of a high protein diet on indices of health and body composition--a crossover trial in resistance-trained men. J Int Soc Sports Nutr. 2016a; 13: 3. PMID: 26778925
• Antonio J, Ellerbroek A, Silver T, et al. A high protein diet has no harmful effects: a one-year crossover study in resistance-trained males. J Nutr Metab. 2016b
• Arslanow, Anita, et al. "Short-Term Hypocaloric High-Fiber and High-Protein Diet Improves Hepatic Steatosis Assessed by Controlled Attenuation Parameter." Clinical and Translational Gastroenterology 7.6 (2016): e176.
• Brinkworth, G. D., et al. "Long-term effects of a high-protein, low-carbohydrate diet on weight control and cardiovascular risk markers in obese hyperinsulinemic subjects." International journal of obesity 28.5 (2004): 661-670.
• Clifton, Peter M., Jennifer B. Keogh, and Manny Noakes. "Long-term effects of a high-protein weight-loss diet." The American journal of clinical nutrition 87.1 (2008): 23-29.
• Dumesnil, Jean G., et al. "Effect of a low-glycaemic index–low-fat–high protein diet on the atherogenic metabolic risk profile of abdominally obese men." British Journal of Nutrition 86.05 (2001): 557-568.
• World Health Organization, Food and Agriculture Organization of the United Nations, United Nations University. Protein and amino acid requirements in human nutrition: Report of a joint FAO/WHO/UNU expert consultation (WHO Technical Report Series 935). 2007.
• Xu, Hong, et al. "Dietary fiber, kidney function, inflammation, and mortality risk." Clinical Journal of the American Society of Nephrology (2014): CJN-02260314.

3-4 Egg Yolks per Day May Normalize Your Lipids, Reduce Liver & Abdominal Fat as Well as Your CVD & NAFLD Risk

Three whole eggs deliver the most effec-tive "dose" of  egg yolk to improve your blood lipid levels - more specifically: triglycerides ↓ and LDL ↓ but HDL ↑

Because of their cholesterol content, eggs have long been touted as a driver of heart disease. As a SuppVersity reader, you know that there are multiple reasons why the notion that the consumption of eggs, or rather egg yolks, would increase your cardiovascular disease risk: (a) there's no mechanistic "if your cholesterol is high, your CVD risk is also high"-link; (b) a causative link between the consumption of dietary cholesterol and serum cholesterol does not exist - at least not in the majority of people; (c) substances in egg yolks, in particular, have been shown to modulate the physical characteristics of your lipoproteins (learn more) and will thus lower, not increase your CVD risk.

Since you know all that, it may seem less important for you than your doctor and other people who may still believe that cholesterol was a dietary villain you'd better avoid altogether to read about egg yolks recently discovered ability to significantly decrease your blood lipid levels.

Whole eggs are also an excellent source of dietary protein

Are You Protein Wheysting?

5x More Than the FDA Allows!

More Protein ≠ More Satiety

Protein Oxidation = Health Threat

Protein Timing DOES Matter!

More Protein = More Liver Fat?

Ok, eventually, this preliminary study confirms the ability of egg yolks to reduce the blood lipid levels in rats, not men. Its results are yet in line with human studies (Fernandez. 2006) and case reports such as Fred Kern Jr's paper with the telling title "Normal plasma cholesterol in an 88-year-old man who eats 25 eggs a day", a paper that was published in the New England Journal of Medicine in 1991, a decade during which the number of people, let alone well-known scientists who questioned the detrimental health effects of cholesterol was low, if not zero.

Table 1: Fatty acid profile and cholesterol content of pork belly oil and egg yolk (% of total fatty acid | Park. 2016)

Today, people (including a handful of doctors and scientists ;-) acknowledge that the ingestion of eggs has been reported to lower, not increase blood cholesterol levels. In the absence of a mechanistic explanation for this phenomenon, however, large parts of the medical establishment still doubt that the anti-CVD and anti-cancer effects of eggs are driven by anything but their relatively high content of anti-oxidants. To identify the actual biochemical metabolic mechanisms by which the oral administration of egg yolk affects blood lipid reduction scientists from the Kangwon National University conducted a preliminary rodent study in which they observed similar reductions in 'bad' blood triglycerides and total cholesterol, as well as increases in 'good' high-density lipoprotein cholesterol as they were observed in the egg eating minority of human subjects in epidemiological studies.

Question: Do the eggs have to be raw? No, probably not. As you've learned in my often-cited article on oxysterols (~oxidized cholesterol), it may yet be a bad idea to eat hard-boiled eggs. Why's that? Learn more in this SuppVersity Classic: "True or False? Butter, Ghee, Lard & Tallow - Are Saturated Animals Fats the Kings and Queens of the Frying Pan?" | read it!

This alone may not sound exciting enough for yet another rodent study to make it into the SuppVersity news. What is exciting enough, though, is the fact that the study is the first study to include another high cholesterol product in a control diet: pork belly oil - an "egg yolk analogue" that has a similar, but not identical fatty acid content as egg yolk (see Table 1); and here's how the study that obviously had a saline control group, as well, worked:

• rats were fed, ad libitum, a purified pellet diet and drinking water for 6 weeks, and egg yolk or other treatments were orally administered every day at a fixed time;
• the amount of egg yolk / pork belly oil, namely 5mg/kg, i.e. the human equivalent of approximately 3-4 egg yolks, had been determined based on data from preliminary experiments in which the authors found that this was the amount of egg yolk where the blood lipid lowering effects plateaued (i.e. didn't increase further, when more egg yolk was fed);
• feces, blood, weight and food intake were measured and/or analyzed daily / weekly;
• liver and abdominal fat were determined at the end of the 6-week study

The rats' food intake was examined every 3 days. Their body weight was measured once per week. Based on this data the so-called "diet efficiency" was calculated as the ratio of the diet intake to the daily average body weight gain (diet intake/body weight gain).

Figure 1: Body weight gain and diet intake of rats after oral dosing of egg yolk (Park. 2016).

As you can see in Figure 1, the latter, i.e. the "diet efficacy", was significantly higher for the pork-belly oil group (T2) in which the rodents gained significantly more body weight, even though they had a (likewise significantly) reduced food intake.

Beyond cholesterol: weight and body composition improve as well

Against that background, it is not really surprising that the animals "pork belly group" had also accumulated more abdominal and liver fat than those who were fed with egg yolk and ended up being a non-significant 10% leaner (as in having 10% lower abdominal fat masses) than their peers who received nothing but slightly salted water (saline placebo) on top of their std. rodent diet.

Figure 2: Liver weight and abdominal fat weight in gram per 100g body weight (Park. 2016).

The actual news, however, are the health-relevant improvements in triglycerides, HDL-C and LDL-C as well as the reductions in the predictors of selected heart and liver disease, namely the atherogenic index (AI) and the levels of the transaminase enzymes ALT and AST you can see in Figure 3 - changes of which scientists have concluded in other studies that they are indicative of significant metabolic improvements with downstream beneficial effects on your heart and metabolic health; effects for which the study at hand is the first to provide a mechanistic explanation.

What's the latest on egg yolks: While egg yolk is more and more appreciated "as a source of valuable biologically active substances" (Zdrojewicz. 2016 | learn more in FFT), I am pretty sure that future studies will add to the increasing evidence of the health benefits of egg yolk consumption, such as the recently confirmed anti-NAFLD effects in low protein diets (Erami. 2016), or the previously discussed high amount of 'active' vitamin D in egg yolks. Needless to say that the SuppVersity is the place to learn about these studies, first.

Figure 3: Atherogenic index (top, left), liver enzymes (transaminases ALT and AST | top, right) and lipid levels (triglycerides - TG; total cholesterol - TC; HDL; LDL | bottom | Park. 2016).

The explanation revolves around the significant reduction in (compared to pork belly oil) or rather normalization (compared to control and pork belly oil) of HMG-CoA, the enzyme that's responsible for the endogenous production of cholesterol and the promotion of cholesterol excretion - two potential mechanism, of which Park and Park point out that they are "supported by previous reports that investigated blood lipid reduction in rats that ingested boiled egg and found an increase in LDL-C in the group given pork belly oil (Houston et al., 2011 )" and in line with the fact that "many studies have emphasised that there is no correlation between the amount of egg ingestion and blood cholesterol in humans (Herron et al., 2004; Greene et al., 2005)" as well as studies showing that "lecithin in the egg yolk lowers the level of blood cholesterol, as it is used for the formation of micelles in the small intestine or increases excretion through the reabsorption of cholesterol as bile acids (Yang et al., 2007; Alqasoumi, 2014)".

You as a SuppVersity reader know that eggs, or more specifically their yolks are nutrient dense superfoods that will improve the structure of your choles-terol molecules, leave your cholesterol levels unchanged and, as I have pointed out only recently in my article "Whole Eggs Can Boost Your Beta-Carotene and Vitamin E Uptake from Veggie Salad W/ Oil Dressing by 400%-700%", improve the absorption of fat-soluble vitamins sign. more than one would expect if the effect was a result of their fat content, alone | more!

Eggs, cholesterol, CVD and the metabolic syndrome: With statin-like effects on HMG-CoA and their ability to reduce the uptake of dietary cholesterol from the diet, the small egg-shaped cholesterols bombs (eggs also contain sign. more cholesterol than pork-belly oil) come with everything it takes to keep their effect on your cholesterol levels neutral / beneficial.

In fact, the data from the study at hand indicates that the consumption of 3-4 eggs / day is heart healthy and can help you prevent the accumulation of fat in both, the midsection, as well as the subjacent liver. Two good reasons to eat more eggs, especially in view of the fact that the deposition of fat in the liver is supposedly the starting point for the development of diabetes, heart disease and a plethora of other pathological reasons to die prematurely. When you think about it, it would thus not even be hilarious if egg producers put the (non-FDA approved) claim that eggs "may reduce the risk of heart disease" on the boxes of their produce | Leave a comment on Facebook!

References:

• Alqasoumi, Saleh I. "Evaluation of the hepatroprotective and nephroprotective activities of Scrophularia hypericifolia growing in Saudi Arabia." Saudi Pharmaceutical Journal 22.3 (2014): 258-263.
• Cohn, Jeffrey S., et al. "Dietary phospholipids, hepatic lipid metabolism and cardiovascular disease." Current opinion in lipidology 19.3 (2008): 257-262.
• Erami, Kazuo, et al. "Dietary Egg Yolk Supplementation Improves Low-Protein-Diet-Induced Fatty Liver in Rats." Journal of Nutritional Science and Vitaminology 62.4 (2016): 240-248.
• Fernandez, Maria Luz. "Dietary cholesterol provided by eggs and plasma lipoproteins in healthy populations." Current Opinion in Clinical Nutrition & Metabolic Care 9.1 (2006): 8-12.
• Greene, Christine M., et al. "Maintenance of the LDL cholesterol: HDL cholesterol ratio in an elderly population given a dietary cholesterol challenge." The Journal of nutrition 135.12 (2005): 2793-2798.
• Herron, Kristin L., et al. "High intake of cholesterol results in less atherogenic low-density lipoprotein particles in men and women independent of response classification." Metabolism 53.6 (2004): 823-830.
• Houston, D. K., et al. "Dietary fat and cholesterol and risk of cardiovascular disease in older adults: the Health ABC Study." Nutrition, Metabolism and Cardiovascular Diseases 21.6 (2011): 430-437.
• Kern Jr, Fred. "Normal plasma cholesterol in an 88-year-old man who eats 25 eggs a day: mechanisms of adaptation." New England Journal of Medicine 324.13 (1991): 896-899.
• Park, Byung-Sung and Park, Sang-O. "Lipid-lowering mechanism of egg yolk in normal rats." International Journal of Food Science and Technology (2016) - doi: 10.1111/ijfs.13216
• Yang, Su Young, et al. "Effect of lecithin intake on lipid metabolism and antioxidative capacity in rats fed high fat diet." Korean Journal of Nutrition 40.4 (2007): 312-319.
• Zdrojewicz, Zygmunt, Marta Herman, and Ewa Starostecka. "Hen's egg as a source of valuable biologically active substances." Postȩpy higieny i medycyny doświadczalnej (Online) 70 (2016): 751.