Best HMB Supplement

Resistance training can play a critical part in your health regimen. That's especially true if you're trying to increase muscle mass while decreasing body fat — a process known as body recomposition1 — or if you're losing muscle mass to natural or pathological causes. The tricky thing is that body recomposition involves opposing objectives (calorie surplus versus calorie deficit), and maintaining muscle in the face of biological or pathological factors is no easy feat, either.

Using an HMB supplement could be the key to overcoming the challenges of muscle retention. Because of HMB's ability to prevent muscle loss, it has begun to grow in popularity among strength trainers trying to balance bulk gains and weight loss, as well as people experiencing age- or disease-related muscle loss.

With any rising star in the supplement space, it can be a chore to separate the good from the bad and the great from the good. So we've done the sifting for you and compiled our findings in this guide.

If you’re rushed, here’s a handy summary of our top choices from the HMB market. The sections that follow it detail how we decided on our shortlist.

Over the past two decades, Innerbody Research has helped tens of millions of readers make more informed decisions involving staying healthy and living healthier lifestyles.

Our guide to finding the best HMB supplements started with research. We dove into more than 40 scientific studies in addition to reviews and other unbiased sources to understand what HMB can do, how it works in the body, and what criteria would reasonably inform our recommendations. We then applied our research to find the top brands and played the part of the customer — comparing options, weighing costs, and ordering the products we'd identified as market leaders. Finally, with the products on hand, we tried them for ourselves so we could provide primary reports about the user experience.

Additionally, like all health-related content on this website, this guide was thoroughly vetted by one or more members of our Medical Review Board for accuracy.

We will, of course, continue to monitor the HMB supplements space, taking note of when new products arise or existing products change. That way, we're able to ensure that our recommendations remain relevant and up-to-date.

Our main criteria for this guide were effectiveness, safety, and cost. We want to make sure you're getting a supplement that's truly capable of helping you retain muscle mass with as few health risks as possible, and at an accessible price point.

Convenience rounds out our criteria. With any daily supplement, ease of use is bound to impact the customer experience.

(One note: Most of our recommended HMB brands are powders, which normally include a taste criterion. But all of the powders we tested weren't just unflavored but really too flavorless to remark upon. The only brand that imparted any noticeable taste at all was Life Extension, but even then, it tasted largely of the liquid into which it was mixed. We discuss the matter further later in the guide.)

Effectiveness

Winner: Life Extension Wellness Code Muscle Strength & Restore Formula

First, a disclaimer. There are two forms of HMB: calcium salt (HMB-Ca) and free acid (HMB-FA). All of the HMB supplements we recommend are HMB-Ca. That's not because it's necessarily the more effective form. Rather, as we'll discuss in a later section ("What is HMB?"), the available research is conflicting, but most studies to date have used the calcium salt variety. With more science to back its use, HMB-Ca is something we can more readily support.

Life Extension Wellness Code is our winner for effectiveness for three reasons:

Although Double Wood, Bulk Supplements, and Transparent Labs fall short of Life Extension in dosages, each has merits that make it suitable for a particular subsect of HMB users. Namely, Transparent Labs' creatine-blended formula best serves those who want to build muscle, while Double Wood's and Bulk Supplements' respective 1g and 980mg doses may better suit lower-weight users whose priorities lean toward retaining functionality instead of maximizing body mass (e.g., those who are elderly, sedentary, or ill).

Safety

Winner: Life Extension Wellness Code Muscle Strength & Restore Formula

HMB is generally quite safe. Clinical trials have uncovered no significant side effects in doses up to 3g, and even 6g doses for a 170-180lb human have been shown to present little to no risk.19 20 21 With the products in this guide, the potential health hazards largely arise from additional ingredients, like the creatine in Transparent Labs. But since three-quarters of our recommendations are absent such additions, we looked to other measuring sticks to identify our safety winner.

Regular Innerbody readers are probably aware the United States Food & Drug Administration (FDA) doesn't approve dietary supplements before they go on the market; it only performs enforcement activities post-market and requires manufacturers to register their facilities.10 11 Therefore, in many of our guides and reviews, we center our safety evaluations on companies' operational practices, looking for distinctions that point to how they preserve consumer well-being — for example:

• GMP/cGMP compliance: Adherence to (Current) Good Manufacturing Practice ensures consistency and control during production.12 13 That, in turn, helps ensure high quality, which is closely tied to product safety.
• Third-party testing: Submitting materials and products for analysis by an independent third party verifies quality, safety, purity, and potency without bias.
• Certificates of analysis (COA): A COA is a document prepared by a lab that has analyzed a product or material. When a company is willing to provide a COA to consumers, it helps inspire confidence in its product's quality.
• NSF certification: The NSF, which oversees product safety, certifies products, facilities, and procedures that meet high safety standards.14
• USP verification: USP verification can pertain to products and ingredients. It validates a company's cGMP compliance, quality controls, and lab testing, among other things.

Our safety evaluations ordinarily reveal one outstanding brand whose practices go over and beyond the others, but that wasn't the case here, as all of our top recommended HMB brands can boast of at least the first three safety distinctions listed above. Only Life Extension and Bulk Supplements have an additional claim to NSF certification, while Life Extension and Transparent Labs both use a USP-verified form of HMB. So Life Extension pulled ahead of the pack.

As a cherry on top, Life Extension had another distinction up its sleeve: It performs independent, third-party testing at multiple stages of production. Not only its finished products but also its raw materials are analyzed for purity and quality. The company simply checks all of the right boxes, and then some.

Cost

Winner: Bulk Supplements HMB

A combination of a low up-front price and a high serving quantity makes Bulk Supplements the go-to HMB for the most budget-conscious consumers. A 100g bag delivers 100 servings and has a base price of $16.96 ($0.17 per serving) as a one-time purchase and $15.26 ($0.15 per serving) as a subscription. Even after you account for its shipping cost — the highest on our list, at $9.94 — its per-serving cost is just $0.26, around $0.07 lower than our runner-up.

That runner-up is Double Wood. A 120-capsule bottle costs $19.95 as a one-time purchase and $15.96 as a subscription. Shipping is free, so it's just about neck-and-neck with Bulk Supplements in terms of the up-front cost. But a serving size is two capsules, so every serving is equivalent to around $0.27-$0.33. Not all that more expensive than Bulk Supplements, but enough to relegate Double Wood to second place. (You can lower your per-serving cost by buying bundles, but then you'd have to contend with much higher up-front costs.)

Life Extension is our third-place finisher in the cost category. Its Wellness Code has a one-time cost of $24.75 and a subscription cost of $22.50. A jar contains 30 servings, so you're looking at around $0.83 and $0.75 per serving, respectively.

Transparent Labs is where the cost really enters a different bracket. A one-timer is $49.99 and a subscription is $45.99. With 30 servings per container, that's around $1.67 and $1.53 per serving, respectively. Its higher price is likely due to its dual purpose (muscle retention and muscle building).

Convenience

Winner: Double Wood Supplements HMB

Double Wood wins the convenience category because it's the only HMB supplement on our list that isn't a powder. To take it, just tip out a couple of capsules and wash them down with a drink. The capsules are on the large side (around seven-eighths of an inch long and a quarter inch in circumference), but as long as you don't have trouble swallowing pills, they ought to provide a quicker, more convenient user experience compared to the other brands on our list.

Regarding those other brands, we evaluated their convenience based on a few factors:

• Product packaging: Is it easy to access the contents? Does the packaging help avoid spillage?
• Ease of measuring: Does it come with a pre-measured scoop, or do we need to break out the digital scale?
• Solubility: How quickly does the powder dissolve when stirred into cold water? Is there any suspension or settling?

After we'd completed use testing, we concluded that Life Extension and Transparent Labs were tied for second place. Both come in wide-mouthed jars with pre-measured scoops, which make it easier to portion your servings without making (too much of) a mess. They also stir easily into cold water, though with different degrees of effort; Transparent Labs reached sufficient dissolution in about 10 seconds, while Life Extension took around 30 seconds.

Bulk Supplements is the only one of our HMB recommendations we would describe as inconvenient. Though it dissolves the fastest in cold water, it also comes in a narrow-profile bag whose relative instability and restricted opening increase your likelihood of spilling scoops. And as for scoops, you'll have to provide your own because you won’t find one in the bag.

The table below shows how our top recommended HMB brands compare in terms of cost, servings, composition, and other factors that may influence your purchase decision. (Please note that the information in the table relates to the smallest package size, as other size options correspond to different price points and serving amounts. Also note that the per-serving cost doesn’t account for shipping.)

HMB is beta‐hydroxy‐beta‐methylbutyrate (a.k.a. hydroxymethylbutyrate). It's a chemical metabolite that results from the breakdown of leucine, an essential branched-chain amino acid that can prevent or mitigate muscle cell damage. Specifically, leucine signals protein synthesis,15 the metabolic process by which the body builds new proteins such as muscle cells. Because of its properties, HMB can be especially useful to people at risk of losing muscle mass because of:

• Calorie restriction
• Aging
• Wasting syndrome

The human liver produces HMB endogenously, but it can also be obtained through food sources (e.g., catfish and grapefruit)16 and synthetic supplements.

As a supplement, HMB comes in two forms: calcium salt (HMB-Ca) and free acid (HMB-FA). The scientific consensus is divided as to which one is better. According to a 2010 study published in the British Journal of Nutrition, HMB-FA may be the better version because it's absorbed and retained better in plasma.17 But ask the authors of a 2024 review in Amino Acids, and you'll hear that HMB-Ca is better owing to its superior bioavailability and faster absorption.18

So, how to choose between them? Well, what we can say is:

• The ISSN's position is that "research with HMB-FA is in its infancy."2
• There's a much larger body of research on HMB-Ca.

Therefore, at this time, all of our HMB recommendations are the calcium salt variety.

HMB is generally considered safe when used within recommended doses — and potentially even when used in excess. Several studies throughout the years can attest to its safety status. Below, we discuss a few of them.

• A series of two experiments in 1996, concerning the effects of HMB on muscle metabolism, provided subjects with 0-3g of HMB per day and found no adverse effects in either study.19 (Remember, none of our top recommendations provide more than 3g of HMB.)
• A 1997 review covering nine studies involving various participant demographics identified no differences in self-reported adverse events compared to placebo, and there were no negative effects on the serum parameters of blood chemistry or hematology in subjects who consumed 3g of HMB per day.20
• And a 2000 study followed 37 untrained men who took varying amounts of HMB (0, 38, and 76mg/kg — equivalent to 0, 3, and 6g in a 170-180lb human) for eight weeks and uncovered no adverse effects on liver function, kidney function, lipid profile, or the immune system.21

With all that being said, a particular HMB supplement may contain other ingredients that do present side effect risks. For example, Transparent Labs Creatine HMB has 5g (5,000mg) of creatine monohydrate, and although it's within the recommended dose range, creatine supplementation has been known to cause symptoms such as:22

• Muscle cramps
• Gastrointestinal upset
• Dizziness
• High blood pressure
• Liver or kidney problems (including one case of sudden kidney failure with excessive dosing — 10g per day)

There’s also Vitamin D to consider, which is an active component in two of our recommendations — Life Extension Wellness Code and Transparent Labs Creatine HMB. The Office of Dietary Supplements warns that consuming more than the tolerable upper intake level (100mcg/day for adults) is toxic and can lead to higher-than-normal calcium levels,4 which is concerning given the significant calcium quantities that come with HMB-Ca. The associated side effects include but aren't limited to:4

• Nausea
• Vomiting
• Dehydration and thirst
• Kidney stones
• Appetite loss
• Kidney failure (extreme cases)
• Irregular heartbeat (extreme cases)
• Death (extreme cases)

Therefore, you should avoid creatine-based HMB supplements if you have a history of related health issues (e.g., kidney disease, liver disease, hypertension) and monitor your broader vitamin D intake to prevent overdosing. And, as with any supplement, it’s advisable to speak to your doctor or nutritionist while you contemplate adding anything new to your routine.

Because of HMB's ability to help users retain muscle mass, an HMB supplement can best serve the following populations:

As always with a supplement, there are some populations who should avoid it. However, owing to the dearth of research on common populations for exclusion, it's not entirely certain what those populations are for HMB. For example, one of the few studies on pregnant populations, though positive, was performed on pigs,31 and there's no way to be certain how the findings would translate in humans. Until more research is done, the safest thing for a pregnant woman to do is avoid HMB unless approved by a physician.

Best overall HMB supplement and winner for safety

Life Extension is a brand that appears in a few of our guides and articles, including one dedicated review. Based in Florida, the company has a wide-ranging product line that comprises supplements and at-home lab tests.

The Wellness Code Muscle Strength & Restore Formula is an unflavored HMB powder that’s part of Life Extension's Active Lifestyle & Fitness collection. Every one-scoop serving delivers a clinically relevant 3g (3,000mg) of HMB — specifically, a branded form called myHMB, whose USP verification speaks to its strength and purity (discussed later in this section). Seeing as the average American weighs 181lb, or around 82kg,32 we'd say that aligns well with the 38mg/kg dosage recommended by the International Society of Sports Nutrition (ISSN).2

The Wellness Code formula also includes significant quantities of two other active ingredients:

In addition to its ingredients, Wellness Code has a strong safety pedigree behind it because Life Extension has a reputation for upholding high quality standards, as validated by:

• NSF certification: The NSF is a globally recognized organization that oversees health standards. Life Extension's quality assurance and quality control procedures are NSF-certified, which means they "meet strict standards for public health protection."14
• GMP registration: "GMP" stands for "Good Manufacturing Practices," and GMP registration verifies that a company adheres to such practices in the manufacture of its products.38 Life Extension's quality and distribution systems undergo biannual audits so the company can maintain its registration.
• USP verification: Toward the beginning of this section, we said that Wellness Code uses a branded form of HMB called myHMB, which is USP verified. Earning and maintaining USP verification entails auditing manufacturing sites for cGMP compliance, reviewing quality control and manufacturing documentation, and lab testing of product samples, along with annual monitoring thereof.39
• Third-party testing: Life Extension subjects both its raw materials and its finished products to independent, third-party testing, thus ensuring quality, purity, and potency.
• Certificates of analysis: Life Extension offers certificates of analysis for each of its products.

Granted, all of the brands in our guide are GMP-compliant, offer certificates of analysis, and submit their products for third-party testing, but only Life Extension can boast of both having USP verification and using a USP-verified ingredient. Also, Life Extension is the only brand on our list that tests both raw materials and finished products for purity and potency. That's why its Wellness Code formula is our winner for safety.

User experience

Life Extension Wellness Code comes with a pre-measured scoop that accurately doses out the recommended 3.14g dose, as measured on a kitchen scale. Like the other two powders we recommend, Wellness Code dissolves easily in cold water, though it may need a bit more agitation compared to the others. In our testing, it needed 20-30 seconds of stirring to fully dissolve, whereas Transparent Labs took about 10 seconds and Bulk Supplements dissolved almost immediately. In fairness to Wellness Code, its label directions do say to use a shaker cup or blender, preferably in combination with a protein shake. We used only cold water to add an element of standardization to our convenience testing.

By the way, Wellness Code is the only HMB on our list with a noticeable taste, though even that's subtle. It's more like a vague mineral quality than anything truly off-putting. If you follow the label directions and mix it into a protein shake, you won't even know the taste is there.

Pricing, subscription, shipping, and returns

Life Extension Wellness Code is available exclusively as an unflavored powder in a 3.32oz jar. A one-time purchase costs $24.75 and an auto-shipped subscription is $22.50. Since a single jar provides 30 servings, the per-serving cost is around $0.83 and $0.75, respectively. Among our recommendations, only Transparent Labs Creatine HMB costs more. But since Transparent Labs costs twice as much per serving, it would be fairer to say Wellness Code is the third-least, not the second-most, expensive product on our list.

For subscriptions, you can choose anywhere from one- to 12-month delivery intervals (the widest range of intervals among our HMB recommendations). Now, the label directions say to use the powder daily, but you could moderate your use instead. Say that you take a serving only on workout days; if you work out three times a week, a single jar would last you two months with several servings' worth of surplus. In that case, a two-month delivery interval would suit you best. Of course, anyone planning to take Wellness Code regularly probably wouldn't have much use for any interval beyond that.

All subscriptions of Wellness Code ship for free, as do one-time orders above $50. Otherwise, tack on $5.50 for standard shipping, by which your order should arrive in 3-5 days (ours reached the doorstep in three). For added cost, you can opt for UPS 2nd Day Air or UPS Overnight. Life Extension ships internationally, as well. Orders to Canada are a flat-rate $19.50. Air mail rates apply for deliveries elsewhere.

We've praised Life Extension's return policy in other articles, and we want to repeat the praise here. You have a very generous 12 months from your purchase date to ship your order back for a refund, even if you've opened and used the product. In contrast, Bulk Supplements, Double Wood, and Transparent Labs have only 30-day return windows.

Best HMB supplement on a budget and runner-up for safety

Bulk Supplements' wheelhouse is making quality supplements at affordable costs, so the fact that its HMB is our budget pick is no big surprise. For our testing, we purchased the 100g bag of HMB powder, which provides 100 servings for $15.26-$16.96 ($0.16-$0.17 per serving). Both the up-front and the per-serving costs are the lowest among our top recommendations, at least before the shipping is calculated.

Aside from being our most cost-effective HMB option, Bulk Supplements is our runner-up for safety. The company doesn't use a USP-verified ingredient, nor does it claim to run third-party tests on raw materials, but it does have the distinction of producing its supplements in an NSF-certified facility. On top of that, the company will provide certificates of analysis on request, and its operations, too, are GMP-compliant.

Technically, Bulk Supplements HMB powder delivers 980mg of HMB-Ca, but unlike Life Extension and Wellness Code, the calcium content isn't counted separately. Really, you're getting 825mg of HMB and 155mg of calcium salt. The per-serving amount of HMB is the lowest among our recommendations, but the directions suggest taking two daily servings, which would give you 1.65g of HMB per day — slightly more than Transparent Labs' 1.5g dose and almost enough to meet the needs of low-weight users (those around 50kg, or 110lb) based on the ISSN's recommendations.2 Also, the 155mg of calcium, while less than half the amount of Life Extension, is significant and only barely lower than Double Wood's 164mg.

User experience

Of the HMB products we've tested, Bulk Supplements HMB powder is the only one that distinguishes itself as inconvenient. It may be the fastest-dissolving powder among our recommendations, but its product packaging leaves a lot to be desired. While Life Extension and Transparent Labs come in wide-mouthed jars with pre-measured scoops, Bulk Supplements comes in a bag sans scoop. The bag has a narrow profile, so the top has a restricted opening that makes for somewhat burdensome access. Also, the instructions on our bag say a serving size is two-fifths of a teaspoon, which isn't all that easy to portion. We say "our bag" because Bulk Supplements has updated the serving size to one-half teaspoon since we received our order. If you purchase the updated version, then you'll have an easier time with portioning. If not, you may want to get yourself a milligram scale since teaspoons don't normally come in one-fifth increments.

Pricing, subscription, shipping, and returns

A 100g bag of Bulk Supplements HMB powder costs $16.96 ($0.17 per serving) as a one-time purchase and $15.26 ($0.16 per serving) as a subscription. Other size options and a capsule alternative are available, but we relegated our testing to the 100g bag because we concluded its up-front price point was the most readily accessible to the widest possible audience.

Here's how the pricing breaks down for the other options:

Bear in mind that your per-day expense may differ from the per-serving costs we've mentioned. If you take two servings per day, double the per-serving cost to calculate your daily use cost.

Subscription delivery intervals are 1-6 months. Your options are more limited than with Life Extension, but they're still quite diverse.

A downside with Bulk Supplements is that shipping costs are pretty high — higher, in fact, than with any other brand on our list. Economy shipping is $9.95, and optional $3 shipping insurance is tacked on by default. Expedited shipping is available but, of course, at higher costs. International shipping is available, at least, and shipping tends to be fast (we received our order in two days from the purchase date). Plus, even with the high shipping, you still have a lower per-serving cost than the runner-up for cost, Double Wood.

The return policy isn't that great, either. Like Transparent Labs and Double Wood, Bulk Supplements allows returns within a 30-day window from your invoice date. Only unopened products are eligible for a full refund. If you've opened your HMB powder, you qualify for a partial refund equivalent to the price of the smallest unit. Your next question might be: “How does the partial refund work if my purchase was already for the smallest unit?” Unfortunately, in that case, you don’t qualify for a refund.

Best low-dose and easiest-to-use HMB supplement

Philadelphia-based Double Wood Supplements differentiates itself from our other recommendations in a couple of ways.

First, its HMB supplement is a capsule. Many users prefer capsules to powders because they're faster to take. You don't need to measure or stir, just chase a couple of caps with a glass of water. (Those who have trouble swallowing pills, however, will disagree.)

Second, the dose is lower. A two-capsule serving delivers 1g (1,000mg) of HMB, which is the lowest amount in our guide (Bulk Supplements has a lower per-serving dose but suggests two servings a day). Now, a few times we've stated that 3g/day is the standard clinical dose, but not everyone should start that high. People with lower body weights need less HMB to realize its benefits (remember, 38mg/kg, per the ISSN),2 and some users just may feel more comfortable starting with the lowest possible measurement. Not to mention, the capsule route of administration makes it very easy to titrate up or down as needed.

And third, while Life Extension, Bulk Supplements, and Transparent Labs are happy to provide you with a certificate of analysis and testing results upon request, Double Wood presents them right on the product page. Although Life Extension is our overall safety winner, Double Wood’s initiative helps reassure us of the company's production and safety practices.

User experience

The Double Wood HMB capsule is on the large side — nearly an inch long and a quarter of an inch in circumference — but it's certainly manageable if you don't have difficulty swallowing pills. (For what it's worth, our testers experienced no trouble with the Double Wood caps.)

By the way, while some supplement capsules can leave an aftertaste, we're happy to report that Double Wood's HMB does not.

Pricing, subscription, shipping, and returns.

At $19.95 for a one-time purchase and $15.96 for a subscription, Double Wood Supplements HMB has the second-lowest up-front cost and the largest subscription discount among our top recommendations. A 120-capsule bottle equates to 60 servings, so the per-serving cost is only $0.26-$0.33 (also the second-lowest on our list).

Double Wood's pricing structure is a fourth point of distinction that may interest some consumers. Unlike any of the other brands we've discussed, Double Wood allows you to bundle your HMB bottles for additional savings. This table below illustrates:

Bulk Supplements still has the lowest per-serving cost no matter how you slice it, but a three-month supply of Double Wood as a one-time bundle costs less than a single one-time purchase of Transparent Labs Creatine HMB.

As to delivery intervals, your choices are between 30, 60, 90, and 120 days. They aren't the most diverse, but neither are they the most limited (the latter distinction goes to Transparent Labs). The 30-day interval should work well for single-user households who don't want to bundle, while the 60- and 90-day intervals work ideally with the double and triple packs, respectively. The 120-day interval is best reserved for irregular users or those buying multiple bundles for a multi-user household.

Here's a plus: Standard shipping is free. Double Wood's website says to allow 5-7 days for your order to arrive, but ours came in just three. Expedited options are available. Also, like our other top recommendations, Double Wood does ship internationally.

The company's refund policy is a combination of positive and not-so-positive. The not-so-positive part is that you have just a 30-day return window, as with Bulk Supplements and Transparent Labs. The positive part is a relatively generous money-back guarantee. Whether you purchase a single item or a bundle, you can get a refund on your first bottle, even if it's used. With bundles, you can even keep one of the bottles and return the rest.

Best HMB supplement with added creatine

Transparent Labs Creatine HMB is unique on our list because it's the only one primarily formulated for gaining mass. Its muscle-building properties come from 5g (5,000mg) of creatine monohydrate, a widely used supplement among strength trainers. The 5g dose of creatine is consistent with studies for safe and efficacious long-term use.40 In fact, this product also happens to be our top recommendation in a separate guide helping women find the best creatine supplement.

As the Cleveland Clinic explains, creatine itself occurs naturally in the body, which uses the compound to help with the flexion of skeletal muscles (the movement you make, for example, when you lift a dumbbell into a curl). Though it's also abundant in protein-rich foods, strength trainers often take additional, synthetic creatine as a supplement to optimize their workouts and maximize muscle gain.41

A 2022 review in Nutrients explains that creatine supplements increase the body's capacity to resynthesize adenosine triphosphate (ATP) during "repeated, high-intensity exercise tasks," such as lifting weights.42 The short of it is this: ATP is a molecule that stores energy and transfers it to cells, and when a cell needs the energy contained within ATP, the ATP gets broken down into another molecule called adenosine diphosphate and then resynthesized to ATP.43 Therefore, during exercise, your muscles can more efficiently use a greater store of energy.

However, only young people may be able to realize strength improvements by supplementing with creatine. Research on older subjects is less promising. Take, for example, a 2020 study on participants aged 49-69, which found that 12 months of supplementation and supervised whole-body resistance training yielded "no greater effect on measures of bone, muscle, or strength ... compared with placebo."44 With that in mind, we'd recommend Transparent Labs Creatine HMB as a performance aid only to younger populations, or at least advise that you temper your expectations if you take the supplement as an older user.

Creatine is just one part of this particular picture. In the Transparent Labs formula, it teams up with 1.5g of USP-verified myHMB (roughly as much HMB as a day’s worth of Bulk Supplements’ product), and together they may have an increased ability to mitigate muscle loss. That’s because creatine, like HMB, has muscle-retaining properties, too, as concluded in one 2021 review and demonstrated in a four-week study conducted in 2018.45 46 More research is necessary to confirm creatine's utility for muscle retention, and the 2018 study used a much larger dose than most studies, but if the findings are correct, Transparent Labs Creatine HMB has the potential to serve a general population of users who want to prevent muscle loss from calorie reduction, physical disuse, or age.

The formula contains 5mg of BioPerine, too. BioPerine is a branded black pepper extract standardized here to contain 95% piperine, an alkaloid known as a bioavailability enhancer. According to the researcher behind a 2013 review on the subject, piperine can increase bioavailability by 30-200%.47 So, with BioPerine playing support, Creatine HMB can impart its intended benefits more effectively, in theory.

By the way, Transparent Labs Creatine HMB is available in 12 flavor varieties, though only the unflavored and Blue Raspberry options are available in both 30- and 60-serving sizes; the rest come exclusively in 30-serving jars. We used the unflavored variety for our tests so we could level the playing field for Life Extension and Bulk Supplements, which come exclusively as unflavored powders.

User experience

Like Life Extension, Transparent Labs provides a pre-measured scoop to portion out its creatine-HMB powder. The scoop is less accurate than Life Extension's, however; we took five separate measurements on a kitchen scale and came up with four different weights, only one of which matched the recommended 7g dose.

For our mixing test, we dissolved Creatine HMB powder in 10oz of cold water, which was on the low end of the range recommended by Transparent Labs. The powder dissolved sufficiently within 10 seconds, though it left the water cloudy, and there was some settling after about one minute. You should consume your Creatine HMB beverage rather quickly to prevent settling; to that end, at least the powder has none of Life Extension’s mineral taste, so it should be easier to gulp down.

Pricing, subscription, shipping, and returns

Transparent Labs Creatine HMB is available in either a 30-serving or a 60-serving jar. (For our tests, we went with the smaller size). As usual, one-time purchases cost more per order than subscriptions. This table breaks it all down:

You can see that even at its lowest price point, Transparent Labs Creatine HMB costs about twice as much as Life Extension Wellness Code, the second-most expensive option on our list. To be fair, the high cost could be partly justified by its dual gain-and-retention utility.

Subscribers will see they have just three delivery intervals to choose from: 15, 30, and 45 days. You're supposed to take one serving per day, so we don't see how the 15- and 45-day intervals align with the label directions. And if you buy a 60-serving jar, none of the intervals correspond neatly to your supply needs.

Shipping is no bright spot, either, since the $7.99 shipping cost is the second-highest among our top recommended brands. Only Bulk Supplements has a higher shipping cost, but it also has a much lower base price. At least international shipping is available, and domestic orders ship pretty fast — just not as fast as Life Extension, Bulk Supplements, or Double Wood (ours arrived in four days).

Even the return policy is the least generous on our list. It entails the same narrow 30-day window as Bulk Supplements and Double Wood, but you don't get the benefit of partial refunds (as with the former) or money-back guarantees (as with the latter). Rather, only unopened items are eligible for any refund at all, whereas opened items qualify for an exchange or store credit.