HMB for Fat Loss

  • By Performance Lab
  • 13 minute read
HMB for Fat Loss

In ye olden days, “weight loss” used to be equated with “fat loss.”

In fact, many supposed “weight loss” supplements today still conflate fat loss with weight loss.

This is, of course, as many bodybuilders now know, an outdated way of thinking. Because sheer “weight loss” isn’t always the best strategy to cutting fat.

Instead, gaining weight—specifically muscle mass weight—has been shown to work much better at long-term fat loss. This is why UFC fighters such as Aljamain Sterling use fat burners containing HMB when preparing for a fight.

This makes intuitive sense: growing muscle requires energy, and what is “fat” but stored energy saved for the purposes of performing high-intensity activities and growing muscle after said “high-intensity activities.”

Top Tip: reducing your calorie count to match your calorie intake is a losing game and not conducive to muscle and strength gains. Instead, increase your energy expenditure to meet your calorie intake by exercising, which also encourages muscle growth for continued calorie-burning when not working out.1

With all that in mind, increasing your muscle mass turns out to be a superior fat loss strategy than merely “losing weight”—i.e., decreasing your calorie intake.

So, it may be said that anything that assists with lean muscle growth may also ultimately double as a fat burner. At least, this is the logic underlying supplementing HMB (β-Hydroxyl β-Methylbutyrate) for fat loss.

However, HMB does more than simply “assist with lean muscle growth.” It’s how HMB does this that makes it such an effective sculpting tool for bodybuilders.

Keep reading to learn more on the benefits of HMB for fat loss, as well as the best fat burner supplements to take with HMB, including a breakdown on the best HMB-containing fat loss formula: Burn Lab Pro®

Let’s get to it.

Why Bodybuilders Take HMB for Fat Loss

Bodybuilding is more than just picking up and putting down heavy objects to look good.

Employing a mix of strength-training, smart dieting, and fat-cutting, the bodybuilder is more artist than athlete. Bodybuilders are sculptors who create magnificently chiseled works of art out of their initially flabby, wet clay-like bodies.

This, of course, requires maximizing anabolic muscle growth while also encouraging fat-burning during exercise without too much exercise-related protein breakdown.

This is why HMB (β-Hydroxyl β-Methylbutyrate), a muscle-sparing, fat-burning amino metabolite, is a favorite pre-workout supplement among bodybuilders.

Especially among bodybuilders who exercise on an empty stomach to expedite their fat loss efforts.

While an effective strategy at burning fat, intermittent fasting and fasted training also make exercising at a high-intensity level difficult.

Likewise, fasted training also threatens to exacerbate muscle breakdown, as the body resorts to muscle protein for muscle energy fuel.

By sparing muscle protein, HMB encourages the use of fat for exercise fuel during fasted training, allowing bodybuilders to work on sculpting their bodies with unimpaired intensity and muscle performance.

HMB vs. Leucine: Which is Better?

As a metabolite of leucine, the most anabolic of the three BCAAs (leucine, isoleucine, and valine), HMB possesses some anabolic properties that benefit muscle growth while indirectly encouraging fat loss, especially while exercising on an empty stomach.

This thus begs the question of which is better: HMB or Leucine?

Simply put, the key difference between HMB and leucine is as follows:

  • HMB is Anti-Catabolic: taken pre-workout, HMB works best as an anti-catabolic agent, meaning it reduces the rate of muscle breakdown.
  • Leucine is Anabolic: taken pre- or intra-workout, leucine works more as an anabolic agent, meaning it promotes an increase in muscle mass growth.

Whereas leucine (especially as part of a complete BCAA stack) more directly encourages lean muscle growth, HMB helps mitigate muscle breakdown, having a muscle-sparing effect that both ultimately encourages greater muscle gains while encouraging the body to use stored fat as exercise energy fuel, as opposed to muscle protein.2

So, really, you don’t have to choose between taking HMB or leucine. An ideal muscle-growth, fat-loss strategy would involve synergizing pre-workout HMB with intra-workout BCAAs (leucine, isoleucine, valine) for anabolic + anti-catabolic lean muscle and strength enhancement.

HMB (β-Hydroxyl β-Methylbutyrate): Full Benefits

HMB works best for building muscle and cutting excess fat when taken immediately prior to exercise.

While similar to leucine, HMB seems particularly geared towards reducing muscle wasting, whether exercise-related or not, under conditions of accelerated muscle atrophy (e.g., while fasted training or intermittent fasting).

HMB seems to work by:

Reducing Muscle Breakdown During Fasted Exercise

Exercising on an empty stomach (e.g., first thing in the morning before breakfast) is an effective, popular strategy to stoke the body’s fat-burning metabolism.

However, high-intensity strength-training and endurance exercise may also encourage proteolysis (protein breakdown), as the fasting body resorts to muscle protein to fuel muscle activity.

Supplementing HMB prior to fasted training may help protect muscle tissue against proteolysis for an overall boost on muscle and strength gains.3

Some research also suggests that HMB may attenuate the fasting-related release of stress hormone cortisol, a catabolic agent that negatively impacts muscle growth and repair.4

Promoting the Anabolic Use of Dietary Protein

By the same formula that “increasing muscle mass helps decrease fat mass,” protein supplements may thus be categorized as indirect “fat loss” agents, much in the same way that HMB is.

In a 2017 study comparing the weight loss effects of a high-protein diet (HPD) to a standard-protein diet (SPD), a small group of researchers observed that “the HPD group lost significantly more weight than adherent participants in the SPD group.”5

This is relevant to HMB’s combined effects with protein supplementation, which has been associated with an increase in muscle gains, specifically leg muscle groups.6

Pairing HMB may help promote the anabolic (muscle-building) use of dietary proteins in service of greater fat-free muscle mass.

Encouraging Fat Burning for Energy

Because HMB’s primary function is to preserve muscle tissue against the catabolic effects of fasting, exercising, and other muscle-wasting factors, the “fat loss” benefits of HMB are only secondary here.

Even so, if your aim is to increase lean muscle mass while cutting all the excess jiggly fat, HMB is virtually a must-have supplement to include as part of your fat-burning regimen.

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The muscle-sparing effects of HMB may also have a performance-enhancing effect as much as a fat-burning one.

In a 12-week placebo-controlled study on HMB supplementation among highly-trained combat sports athletes, HMB was found to promote:

“advantageous changes in body composition and stimulate an increase in aerobic and anaerobic capacity in combat sports athletes.”8

HMB Dosage

A generally safe ingredient, HMB supplementation tends to range anywhere from 1,000 mg to 3,000 mg daily, specifically for the purpose of mitigating muscle loss.

  • 1500mg HMB per workout (i.e., daily) is a clinically effective amount for safely delivering on the muscle-sparing, fat-burning benefits of HMB.

As a metabolite of leucine, HMB is roughly 20X more potent than leucine, again specific to the context of mitigating muscle loss.

This makes 1,500mg HMB roughly the equivalent of 30,000mg leucine (or 30 grams), as well as explaining why HMB is preferred over leucine for the purposes of acutely sparing muscle from exercise-related breakdown in service of a leaner muscle-to-fat ratio physique.

However, again, for the distinct purpose of increasing anabolic muscle growth (as opposed to reducing muscle breakdown), leucine is better suited for the job.

HMB Side Effects

Side effects should not be expected with HMB supplementation, especially if you stay within the 1,500mg HMB daily range. Even dosages upwards of 3,000mg daily have been demonstrated as safe.

Research actually suggests that HMB is somewhat remarkably safe, as no studies have observed any side effects even when taking dosages greater than 3g daily.

No potential adverse side effects have been found in both humans consuming 3-6g daily and animals consuming enormous amounts that would be equivalent to upwards of 450g of HMB per day.8

All the same, it’d be, of course, unnecessarily costly and still potentially risky to consume over 6g HMB daily—let alone 450g HMB daily. Best to stay near the 1.5g to 3g threshold.

Other Beneficial Ingredients to Take With HMB

HMB indirectly encourages fat loss by sparing muscle protein while exercising on an empty stomach.

Of course, this is valuable to maximizing one’s lean muscle gains, but aren’t there also more direct fat burners one can stack with HMB to further maximize their fat loss efforts?

Well, yea, dude!

Here are some of the best ingredients to take with HMB to further increase fat loss:

Coleus Forskohlii (Forskolin)

A prized legendary herb of the ancient Ayurvedic health tradition, Coleus forskohlii is a fairly well-known botanical for its unique ability to boost the activities of cAMP (cyclic adenosine monophosphate), an intracellular messenger compound associated with thermogenic fat loss, anabolic testosterone activity, and synaptic plasticity.9, 10

The primary bioactive constituent of Coleus forskohlii is forskolin, which is largely responsible for the fat-burning, testosterone-boosting, brain-boosting benefits of this herb.

Research has found that Coleus forskohlii supplementation combined with a low-calorie diet may be useful in regulating metabolic risk factors associated with obesity and being overweight.11

Forslean® Coleus Forskohlii Extract

A patented, standardized, research-backed form of Coleus forskohlii, Forslean® is the go-to Coleus forskohlii supplement for burning fat and building muscle.

Precisely calibrated to supply 10% bioactive forskolin, Forslean® is safe, reliable, and well-tolerated with the bonus nootropic benefits of enhanced stress resistance, focus, mood, and cognitive clarity.

Cayenne Pepper (Capsaicin)

A popular food spice, Cayenne pepper is also a well-known thermogenic fat burner, as intuitively understood by many, given that this is a food spice that literally makes people sweat. Which is to say that cayenne pepper quite literally burns calories.

Much of cayenne pepper’s fat-burning properties are attributed to its rich concentration of capsaicinoids, namely capsaicin, a pro-catecholaminergic compound that, like stimulants, provokes the thermogenic activities of norepinephrine, epinephrine, etc. without the typically heart-racing side effects associated with stimulants.

Research on the Capsimax® brand of cayenne pepper extract (see below) has found a significant decrease in calorie consumption and body fat, as compared to placebo—a series of benefits associated with capsaicin’s thermogenic and appetite suppressant bio-effects.12, 13

Capsimax® Cayenne Pepper Extract

Capsimax® is a chili pepper extract standardized to 2% active capsaicinoids, which are protected from stomach acid degradation by unique OmniBead™ beadlet technology.

These microspheres ensure that cayenne’s capsaicinoid content achieves peak absorption before becoming denatured by the digestive process, providing the stimulant-like benefits of cayenne without the stimulant-like side effects or gastric distress.

GTF Chromium

GTF (Glucose Tolerance Factor) Chromium is a trace mineral with natural cofactors found in the likes of brewer’s yeast that help support glucose metabolism and insulin activity.

Key to an overall healthy metabolism, GTF chromium’s insulin optimization benefits help stoke fitness-driven fat loss by:14, 15

  • Regulating appetite
  • Fueling muscle activity
  • Stabilizing energy balance
  • Combating insulin resistance

Essential to metabolic homeostasis, chromium is a simple, yet significant nutritional component to regulating healthy energy use and production, as well as regulating appetite and food intake.

NutriGenesis® GTF Chromium

Complexed with natural whole-food cofactors, such as probiotics, fibers, antioxidants, and enzymes, NutriGenesis® GTF Chromium is an enhanced-bioavailability form of GTF chromium that’s cleaner, more effective, and more eco-friendly than your standard chromium mineral supplement.

Grown in cultures in a state-of-the-art lab, NutriGenesis® GTF Chromium is a nature-identical mineral form that’s easy on the gut and easy-to-absorb—not digestive complications associated with cheaper, inferior micronutrient forms.

Black Pepper (Piperine)

Every supplement, fat burner or otherwise, should include a little black pepper extract in their formula.

In tiny dosages, black pepper extract may significantly improve a formula’s overall bioavailability by increasing the absorption rates of its ingredients.

This explains why certain health foods with low oral bioavailability, such as turmeric, require the addition of black pepper to deliver their benefits.

In the context of fat burning, black pepper’s bioactive spice constituent piperine is also beneficial for stimulating a rise in body heat (thermogenesis) to accelerate calorie burning.

Additionally, piperine seems to help block the formation of new fat cells, resulting in an increase in fat loss and a reduction in fat gains.16, 17

BioPerine® Black Pepper Extract

Patented for increasing the absorption and bioavailability of other nutrients, BioPerine® is found in many different types of supplements with the intent of increasing formula efficacy.

Regardless of the type of supplement, BioPerine® helps maximize the nutritional benefits of foods and supplements.

Burn Lab Pro®

The next-gen fat burner, Burn Lab Pro® is the best HMB-powered fat burner for sculpting a lean, cut physique without resorting to risky stimulants or synthetics.

By shifting body composition from sedentary fat to lean, active muscle, Burn Lab Pro® works with the body’s natural metabolic processes for a healthier decrease in fat and more sustainable increase in muscle mass.

With its innovative design and research-backed ingredients, Burn Lab Pro® unleashes a cascade of research-backed benefits that build on top of one another for a whole-body metabolic overhaul. Think bigger muscles, better performance, and tighter waistline.

Key Benefits

Burn Lab Pro®’s benefits manifest in the following areas:

  1. Fat—Burn Lab Pro® primes the body’s calorie-burning capacity during exercise to maximize your fat loss potential during and after working out.
  2. Exercise—Burn Lab Pro® fuels strength, endurance, and intensity during exercise by encouraging the use of stored fat as exercise energy fuel.
  3. Muscle—Burn Lab Pro® spares muscle tissue against the catabolic effects of calorie-restricted (fasting) exercise to improve lean muscle growth.

In other words, Burn Lab Pro® encourages fat-burning in service of enhanced exercise performance and anabolic lean muscle growth and repair.

As previously covered, muscle growth turns out to be a more effective and sustainable strategy for encouraging fat loss than sheer calorie-restriction.

This is why the best formula strategy for fat-burning involves encouraging lean muscle mass growth while priming the body’s calorie-burning capacity during exercise.

Burn Lab Pro® is just as much a pre-workout performance enhancer as it is a fat burner.

Key Features

  • HMB (β-Hydroxyl β-Methylbutyrate), 1500 mg
  • Forslean® Coleus Forskohlii Extract, 375 mg
  • Capsimax® Cayenne Pepper Extract, 75 mg
  • BioPerine® Black Pepper Extract,75 mg
  • GTF Chromium (as NutriGenesis®), 90 mcg
  • Calcium, 5 mg

The typical fat-burning strategy employed by supplement manufacturers involves cramming pills with an excess of caffeine, or other stimulants, and sprinkling a fairy-dust amount of fat-burning botanicals to give the appearance of well-rounded formula, despite the formula essentially functioning as an overpriced caffeine pill.

Not so with Burn Lab Pro®.

Taking a more natural, stim-free approach to fat-burning, Burn Lab Pro® puts the “health” back in “health supplement,” offering an effective, powerful formula that burns fat the honest way without harmfully spiking your blood pressure or heart rate.

What’s more, Burn Lab Pro® encapsulates its formula in all-natural NutriCaps®, a premium, patented, prebiotic-cultivated capsule constructed out of fermented tapioca (pullulan).

Whereas other brands encase their formulas with weird synthetics that are harmful on the gut, Burn Lab Pro® stays true to its all-natural formula design.

Only clean, green, spicy fat burns here. No synthetics and no stimulants allowed.

Get the best deal on Burn Lab Pro


To maximize fat loss, you need to better strategize your muscle-building game. This involves increasing your energy expenditure to match your energy intake, while also preserving your lean muscle mass gains to encourage the use of stored fat to fuel your muscle activity.

One effective strategy for this is intermittent fasting, or fasted training. Yet, this can be difficult to manage in the long run with no supplementary assistance.

  • By sparing working muscle tissue, HMB encourages the body to burn fat instead of muscle protein to fuel high-intensity exercise on an empty stomach.

And by pairing HMB with other more direct thermogenic fat burners, Burn Lab Pro® only further maximizes your fat-burning potential while assisting with your bodybuilding gains.

This is good news if you’ve been worrying over whether or not you’ll need to commit to a punishing “calorie restricted” diet.

So long as your energy output matches your energy intake, not only will you not have to solely live off of nuts and berries, but the foods you enjoy will be used in service of anabolic muscle growth, not fat storage.

With HMB, Burn Lab Pro® burns fat to build muscle and enhance performance.

And thanks to Burn Lab Pro®’s commitment to clean, natural ingredients, this is an exercise stack you can safely take for daily, long-term fat loss, regardless of your age or dietary lifestyle.

Get the best deal on Burn Lab Pro 


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  3. Gerlinger-Romero F et al. Effects of beta-hydroxy-beta-methylbutyrate (HMB) on the expression of ubiquitin ligases, protein synthesis pathways and contractile function in extensor digitorum longus (EDL) of fed and fasting rats. J Physiol Sci. 2018 Mar; 68(2): 165-174.
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  12. Rogers J et al. Capsaicinoids supplementation decreases percent body fat and fat mass: adjustment using covariates in a post hoc analysis. BMC Obes. 2018; 5: 22.
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  14. Anton SD et al. Effects of Chromium Picolinate on Food Intake and Satiety. Diabetes Technol Ther. 2008 Oct; 10(5): 405-412.
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