The HMB Controversy

[CFC]

Most people even tangentially interested in fitness and bodybuilding have probably heard of the sports supplement HMB. HMB - real name β-hydroxy β-methylbutyrate - is a natural metabolite of the 'anabolic' amino acid Leucine (L-Leucine).

Numerous studies have demonstrated that HMB enhances protein synthesis and inhibits catabolism through a number of mechanisms (some of which we've discussed before >>here<< and >>here<<), particularly in the elderly and those suffering from aged-related sarcopenia.

More recently, however, a few studies have appeared to suggest that HMB is more effective than anabolic steroids at increasing LBM in exercising subjects! The controversy over this research has been brewing for a while now, and you can read more about those studies and the issues raised from last year's discussion over at Strongerbyscience (formerly Strengtheory).

Suffice it to say, the results the scientists claim to have recorded are frankly absurd, and very unlikely to be reliable. And this story has now taken another turn, with a group of scientists writing to the NSCA regarding their financial conflicts of interest in publishing the study. You can read this letter and their critique of the HMB studies over at Anthony Robert's website >>here<<.

The take home message from this controversy is that it pays to remain healthfully skeptical of all outlandish claims attributed to sports nutritional supplements, whether they appear to have scientific backing or not. While HMB is undoubtedly useful - along with its parent amino Leucine - it's not in the same league as an anabolic steroid, as pretty much any AAS-using bodybuilder or powerlifter could tell you.

 

[RedLeader]

CFC, what are your thoughts on leucine ratios to the other amino acids? I've heard of people supplementing with straight leucine (which apparently tastes awful), and then I have heard different arguments for different ratios. I just try and choose foods with high amino amounts, but I haven't paid for an amino supplement in ages. I think I actually have two different brands of amino acids collecting dust somewhere. Just cannot be bothered, even if it would give me an extra tenth of a percent.

I did see one of the weight watcher brand names...might have been Boost...advertising HMB as now part of their shakes. And I think the GNC near me is selling it for some unforgivable price.

 

[Genetic Freak]

CFC, what are your thoughts on leucine ratios to the other amino acids? I've heard of people supplementing with straight leucine (which apparently tastes awful), and then I have heard different arguments for different ratios. I just try and choose foods with high amino amounts, but I haven't paid for an amino supplement in ages. I think I actually have two different brands of amino acids collecting dust somewhere. Just cannot be bothered, even if it would give me an extra tenth of a percent.

I did see one of the weight watcher brand names...might have been Boost...advertising HMB as now part of their shakes. And I think the GNC near me is selling it for some unforgivable price.

A relatively recent concept with potential application to meal frequency is that a certain minimum dose of leucine is required in order to stimulate muscle protein synthesis. (Norton and Wilson; 2009) suggested that this threshold dose is approximately 0.05 g/kg, or roughly 3 g leucine per meal to saturate the mTOR signaling pathway and trigger MPS....

Norton LE, Wilson GJ. Optimal protein intake to maximize muscle protein synthesis: examinations of optimal meal protein intake. Agro Food Industry Hi-Tech. 2009;20:54–57.

Interesting paper on nutrition:

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4033492/


EDIT: Assuming we already have nutrition on point consuming sufficient protein per meal, leucine requirements should be taken care of without need for supplementation..
Taking leucine in isolation would be pointless, as without other amino acids present skeletal muscle hypertrophy wouldnt take place anyway..

 

[CFC]

Leucine does taste particularly yuck lol. It's also difficult to mix (not very water soluble). I've used it and mixed it into various amino/carb/peri-workout combinations over the years.

I doubt it makes a vast difference to your global protein synthesis assuming you eat good quality meals with plenty of leucine in throughout the day. While the mTOR pathway can clearly be activated with more leucine, it will saturate easily with a decent meal, and without other aminos, you will build no muscle at all - though the question of ratios is undoubtedly open to some form of optimisation.

On a calorie-restricted diet, understanding exactly how leucine works could be more significant in two distinct ways - (1) maintaining some degree of anabolism, but also (2) inhibiting fat loss (not good).

 

[Intense]

Off topic sorry.


But Genetic Freak, over at GH15, did GH15 delete your post for being too "intellectual"? Or am I way off lol. I saw that and it made me laugh.

 

[Genetic Freak]

Off topic sorry.


But Genetic Freak, over at GH15, did GH15 delete your post for being too "intellectual"? Or am I way off lol. I saw that and it made me laugh.

Long story... getting rather tired of that place...

 

[Intense]

I believe it.

It's so censored I can't hardly even post over there, and the forum layout is pretty inefficient.

 

[CFC]

Isn't GH15 invite only? Sounds like they just wanted an echo chamber rather than a forum.

 

[Genetic Freak]

Isn't GH15 invite only? Sounds like they just wanted an echo chamber rather than a forum.

It's getting embarrassing, most of the posts are childish drivel.. They would rather hear individual opinion as opposed to scientific research.. We all know individual genetics are so varied it doesn't matter how someone else reacts to various compounds, its how you respond individually that really matters.. Ignorant as pig shit..!!

 

[Intense]

Isn't GH15 invite only? Sounds like they just wanted an echo chamber rather than a forum.

Yes, it used to actually be pretty legit. Some pros posted there etc. and you could get some honest insight. Now it's more of an echo chamber like you say lol. Not saying there aren't knowledgeable posters there but it's certainly changed, and scientific data isn't very welcomed as GF said.

It's getting embarrassing, most of the posts are childish drivel.. They would rather hear individual opinion as opposed to scientific research.. We all know individual genetics are so varied it doesn't matter how someone else reacts to various compounds, its how you respond individually that really matters.. Ignorant as pig shit..!!

Very true. Every forum has it's faults, but I've found one of my favorites to be professionalmuscle(make sure you have adblock lol), specifically posts from the veteran members when they DO actually post.

 

[CFC]

I used to be on ProfessionalMuscle donkeys years ago, glad it's still surviving. Lots of my others kinda died.

 

[RedLeader]

Here is an brand new study I saw earlier on social media. The main takeaway is that given adequate protein intake, leucine supplementation worked no better than the placebo.

They did use untrained individuals, though, which is a pet peeve of mine within experimental design. And I don't know if "adequate dietary protein" implies adequate leucine, given that two different plates of protein could have the same protein but different leucine amounts. The vegan diet, for example, may require much more careful food selection to get comparable leucine to someone eating "Bro."

 

[Genetic Freak]

Most people even tangentially interested in fitness and bodybuilding have probably heard of the sports supplement HMB. HMB - real name β-hydroxy β-methylbutyrate - is a natural metabolite of the 'anabolic' amino acid Leucine (L-Leucine).

Numerous studies have demonstrated that HMB enhances protein synthesis and inhibits catabolism through a number of mechanisms (some of which we've discussed before >>here<< and >>here<<), particularly in the elderly and those suffering from aged-related sarcopenia.

More recently, however, a few studies have appeared to suggest that HMB is more effective than anabolic steroids at increasing LBM in exercising subjects! The controversy over this research has been brewing for a while now, and you can read more about those studies and the issues raised from last year's discussion over at Strongerbyscience (formerly Strengtheory).

Suffice it to say, the results the scientists claim to have recorded are frankly absurd, and very unlikely to be reliable. And this story has now taken another turn, with a group of scientists writing to the NSCA regarding their financial conflicts of interest in publishing the study. You can read this letter and their critique of the HMB studies over at Anthony Robert's website >>here<<.

The take home message from this controversy is that it pays to remain healthfully skeptical of all outlandish claims attributed to sports nutritional supplements, whether they appear to have scientific backing or not. While HMB is undoubtedly useful - along with its parent amino Leucine - it's not in the same league as an anabolic steroid, as pretty much any AAS-using bodybuilder or powerlifter could tell you.

Bump..