We can forgive you if you’ve not heard of HMB before, as it’s not exactly the first thing that springs to mind when it comes to health supplements. But for those who aren’t sure what it is, you’re in the right place to find out!

Otherwise referred to as Beta-Hydroxy Beta-Methylbutyrate (or β hydroxy β methylbutyrate), HMB is a chemical formed from the breakdown of the amino acid leucine.

It’s becoming increasingly used in fat burners and other dietary supplements nowadays, with research showing it can come in handy for body composition, maintaining muscle mass, and much more.

In this article, we will look at what HMB is, what it does, and whether it is worth considering as a supplement.

So, with no further ado, let’s dive in.

What is HMB?

As stated in the intro, HMB is a metabolite formed by the breakdown of leucine (an amino acid). You can find leucine in foods with protein, but only 5% of leucine is turned into HMB.

In recent years, HMB has become an area of interest for many scientists because it appears to be incredibly effective at preventing muscle breakdown, aiding protein metabolism, and may also help you build muscle.

As a supplement, HMB is considered more effective than leucine at preventing muscle breakdown, but it is not anabolic.

As a result, leucine has the edge when it comes to muscle-building benefits. That being said, HMB still appears to help make modest gains.

Can HMB Be Found Naturally in the Diet?

While you can find HMB in leucine and leucine-containing foods, it can also be found in foods such as asparagus, cauliflower, and grapefruit. The problem is that the quantities of HMB within those foods is too small to affect change.

Because of this, it's far better to supplement HMB, as this will allow you to make the most out of its many benefits.

What Does HMB Do?

The body uses HMB to help preserve muscle and prevent muscle loss when on a low-calorie diet.

However, we gain so little of it from the diet and produce such a small amount naturally that it doesn’t really do too much of anything.

As a supplement, HMB has many known benefits and even more potential benefits currently under investigation.

It appears to be a useful supplement for new lifters and may help more experienced lifters on low-calorie diets.

Medically, HMB is used with HIV patients to help prevent muscle wasting or loss, though it is just one of several supplements that may be used.

What are the Benefits of Taking HMB?

In this section, we will look at some of the known effects of taking β hydroxy β methylbutyrate, and some potential benefits currently being studied.

Benefit #1 Reduced Muscle Damage Post-Workout

Hydroxy beta methylbutyrate (HMB) is known to be effective at reducing inflammation and protecting muscle mass, so its use as a post-workout supplement should be a no-brainer.

A 2013 study suggests that resistance-trained men who took it post-workout perceived they were recovering better using it 1.

You may scoff at the fact that it was just their perception, but actually, that’s what you want post-workout. To feel better.

The study concluded that HMB might help to blunt muscle damage and “prevent declines in perceived readiness to train.”

Benefit #2 Increased Muscle Size & Strength

Some evidence suggests that HMB can help to increase muscle mass or build strength.

But as stated earlier, it is predominantly focused on reducing muscle damage and aiding recovery.

Taking HMB can help you train harder the following day, which may account for the increased muscle size and strength.

Benefit #3 Improved Aerobic and Anaerobic Performance

Studies have found that HMB can be effective at improving aerobic performance 2, as well as anaerobic performance (HIIT workouts being tested).

This could be because of reductions in muscle damage or increases in strength and power while taking part in a regular training program.

Benefit #4 Prevents Muscle Loss

This is the most common use for HMB. It is used to prevent muscle loss or wastage in people with HIV while reducing the likelihood of muscle loss in older adults.

As well as this, HMB may be useful for people who are dieting, as prolonged calorie deficits can often lead to some muscle loss. Of course, a high protein diet is just as effective.

Benefit #5 May Lower Blood Pressure

There is some evidence to suggest one effect of beta-hydroxy beta-methylbutyrate is lowering blood pressure 3. However, further research is required to confirm this.

Benefit #6 May Lower Cholesterol

As with blood pressure, some studies are looking at whether HMB may help to lower cholesterol.

However, other studies have found the opposite to be true. Although, this could well be an increase in HDL (good) cholesterol, which is a benefit.

Benefit #7 When Combined With Exercise HMB May Increase Weight Loss

We are reluctant to call HMB a weight loss supplement, as this has a lot of negative connotations.

The fact is that taken alone, it is absolutely NOT a weight loss supplement.

That being said, when combined with a calorie-controlled diet and exercise, HMB in the form of nutritional supplementation can lead to greater weight loss results than through exercise and diet alone.

Are There Any Side Effects?

There are no known side effects of taking HMB in the region of 3-6g per day. Toxicity tests on rats have found that it is non-toxic at rates that would be equivalent to 38g for a 150lb male 4.

It is deemed very safe and is unlikely to cause any harm for the vast majority of people.

But if you are on medication or have an illness, consult with your doctor before taking a supplement such as Beta-Hydroxy Beta-Methylbutyrate to err on the side of caution.

Should You Take HMB?

If you are quite new to lifting and want a supplement that can reduce post-exercise soreness, HMB is a great choice.

It may also help with early increases in muscle strength and size, likely because of its ability to aid protein synthesis.

If you are dieting and want to preserve muscle, you’ll find HMB can benefit you greatly with regular consumption.

Experienced lifters don’t tend to see much difference when they take HMB unless they are in a calorie deficit. But it could certainly help them recover from a challenging workout and may make up a good part of any recovery plan.

HMB appears to have some use as a supplement to a weight loss program, but it is no magic bullet pill. If you take your daily dose and then sit down all day, you simply won’t see any results.

However, if you take it alongside a consistent workout program and a healthy, well-balanced diet, you’ll likely benefit from continued use.


  1. https://pubmed.ncbi.nlm.nih.gov/23286834/
  2. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5566641/
  3. https://www.webmd.com/vitamins/ai/ingredientmono-45/hydroxymethylbutyrate-hmb
  4. https://examine.com/supplements/hmb/research/#safety-and-toxicology_general