Introduction
This is the second article in a three-part series that explores supplements and their value for:
- Performance
- Body composition
- General health
In this article, I focus on supplements that help improve body composition while also providing some context of what body composition means and, ultimately, what we should keep in mind when using supplements to improve it.
Let’s dig in!
A quick recap of the previous article
In the first article, I covered what constitutes a supplement. I also mentioned all three of the top-tier supplements and made background and mechanistic statements about each that I think are worth reading, even if you only consider supplements for body composition. I recommend checking out that article for a complete understanding of how these supplements can interact and support your goals.
Body composition
Generally speaking, when researchers examine body composition outcomes, the focus is primarily on increasing muscle mass or reducing fat mass. A focus on body composition is a bit more holistic than focusing on just weight, because two individuals with the same weight and height can have vastly different distributions of muscle and fat. So, don’t conflate supplements that improve body composition with supplements that promote weight loss. A loss of fat mass without a loss in muscle mass represents an improvement in body composition, but so does an increase in muscle mass without an increase in fat mass.
What can complicate these findings is that resistance training must be present to gain muscle in any notable way, and a Calorie deficit is required to lose a significant amount of body fat. Studies may look to see if using a supplement leads to a spontaneous decrease or increase in these factors, or they may combine it with other elements, such as training or dietary interventions, to assess if the supplement helps improve results. So, with body composition, there are quite a few moving parts, making looking at the details of the studies more important.
As one final complication, most studies investigating the impact of supplements on body composition assess changes in lean body mass (LBM) or fat-free mass (FFM) rather than muscle mass specifically. For various boring technical reasons, it’s far more challenging to assess whole-body muscle mass than whole-body fat-free mass or lean mass. Most of the time, changes in fat-free mass or lean body mass do reflect changes in muscle mass, but there can also be complications. Namely, water is included in fat-free or lean mass, so supplements that affect your tissues’ total hydration can affect your fat-free mass or lean mass more than they affect your actual muscle mass.
| Indicator | Definition | What Affects It |
|---|---|---|
| Body Fat Mass (BFM) | The total mass of fat in the body. | Decreases or increases depending on the loss or gain or body fat. Caloric deficits cause decreases and caloric surpluses cause increases. |
| Lean Body Mass (LBM) | The total mass of lean tissues. This includes bones, muscles, and organs (excludes fat). | Increases or decreases depending on loss or gain of muscle mass. Resistance training and caloric intake will also affect growth or loss. |
| Fat-Free Mass (FFM) | The total mass of all body components except fat. | Will increase with muscle gain and changes in hydration or even carbohydrate status. Can decrease in Calorie restriction. |
| Waist Circumference (WC) | A waist measurement is used to indicate abdominal fat. | Decrease or increase depending on Calorie intake, and can also measure visceral fat levels. |
Top-tier supplements for body composition
Protein supplement
Protein supplementation can support body composition improvements through a few routes. The first and most obvious is by helping to increase lean body mass, particularly muscle mass. Note that muscle growth requires the presence of resistance training and an adequate Calorie intake, and not all studies assure this (or specifically try to ensure it). For instance, if a study on protein supplementation doesn’t show impressive results, it might be because resistance training wasn’t included. When resistance training is part of the equation, research shows that protein supplementation can support the growth of lean body mass and muscle mass.
Furthermore, protein supplements may also promote fat loss. For example, a meta-analysis of randomized clinical trials found that whey protein supplementation led to significant reductions in BMI, as well as nominal (but nonsignificant) reductions in total fat mass.
Consistently, studies show that protein supplementation helps preserve or increase lean body mass across populations from women to older adults. This becomes especially important for older adults since there is a natural decrease in muscle protein synthesis with age.
So, it’s probably no surprise that protein supplementation can help with gaining lean body mass. However, the results are more scattered when considering how well protein supplementation contributes to fat loss. Here are two things to keep in mind: First, protein is an energy-containing macronutrient – it still provides Calories. To lose body fat, we need to reduce overall Calories. Logically, adding extra Calories through protein supplementation while trying to achieve fat loss may not make a lot of sense, or at the very least, it could create complications in achieving that goal. However, protein intake also has a marked impact on appetite and satiety, such that higher protein intakes help to reduce carbohydrate and fat intake. The interplay of these two factors can help explain why adding Calories from protein supplements doesn’t always reduce body fat, but it also doesn’t tend to increase total energy intake or fat mass either.
The other factor to consider is that when you’re in a Calorie deficit, the goal is to retain as much muscle mass as possible. You want to lose fat, not muscle or water weight. In this context, protein supplementation can help preserve muscle during weight loss, which is why the results around fat loss may seem modest. While protein supplements may not directly cause significant fat loss on their own, they play a critical role in ensuring that you’re losing mostly fat (not muscle) when you’re cutting Calories. So, while more significant fat loss due to protein supplementation is unlikely, it can still support the overall body composition goal.
Overall, the support for using protein supplementation is solid. As I said in the first article, this will come down to the presence of overall protein, which does not have to be in supplement form. If you already consume enough protein from whole food sources in your diet, adding a protein supplement probably won’t do much for you. Additionally, there are benefits to whole foods that are not found in supplements. However, if protein supplements help you hit your protein goals, they are great for gaining muscle or preserving lean mass during a deficit.
Creatine
For body composition, creatine can affect multiple markers via a few pathways. The most notable and discussed benefit of creatine use is its ability to assist in lean body mass gains. This systematic review and meta-analysis of creatine supplementation combined with resistance training on body composition in adults under 50 found that those who supplemented with creatine saw a modest increase in LBM pretty evenly in trained and untrained subjects.
Similarly, this GRADE-assessed systematic review and dose-response meta-analysis of creatine supplementation also found modest gains in LBM utilizing a pretty standard dose and duration. The study found that a loading phase of 20g per day for 5-7 days, followed by a maintenance dose of 2-5g per day, could do the job for effective results. As mentioned in the earlier article, loading phases can sometimes lead to digestive discomfort, so if that’s a concern, you can still hit saturation levels, just a little slower.
It’s important to note that increases in lean body mass with creatine supplementation may include changes in water retention. Creatine can draw in water, contributing to an initial rise in LBM. This factor is especially noted during more aggressive loading phases. However, some studies on creatine’s effects account for these changes, suggesting that while water retention is a factor, it’s not the sole explanation for LBM gains – creatine supplementation also increases more direct measures of muscle mass. The positive impact of creatine on LBM likely involves more than just short-term water or glycogen increases. This makes creatine a valid option for those aiming to enhance LBM, with possible benefits extending beyond just water retention.
Regarding decreases in fat mass, a meta-analysis from Forbes et al looked at 19 studies with 609 participants focusing on older adults supplementing with creatine (while engaging in resistance training). The study found the participants showed a small decrease in body fat percentage and fat mass, although the decrease in fat mass was not statistically significant. Desal et al also found decreases in body fat percentage and body fat mass.
What makes creatine’s potential to assist with fat mass loss more interesting is that, unlike protein supplements, creatine doesn’t add any Calories. This means there’s a greater possibility for creatine to contribute to fat loss without the complication of added energy intake. While the effects are modest, if you’re already following a Calorie deficit, creatine could serve as an aid, helping to preserve lean mass while supporting fat loss.
Caffeine
To give a quick reminder, caffeine is known for its stimulatory effects, primarily by blocking adenosine receptors, which help reduce feelings of fatigue and sleepiness. This leads us to the first point: caffeine could assist with body composition, particularly in reducing body fat.
A systematic review and dose-response meta-analysis, which included 13 randomized controlled trials with 606 participants, suggests that caffeine consumption may contribute to reductions in weight, BMI, and body fat. The study also suggested that doubling caffeine intake led to more significant reductions. Mechanistically, the researchers noted that this effect is likely attributed to increased adenosine antagonism (which could increase energy expenditure).
When you think about fat loss in its simplest terms, the goal is to create a sustainable Calorie deficit. While Calorie deficits affect people differently, common side effects include lethargy and fatigue. Caffeine can be beneficial by reducing the extremity of fatigue during these energy-restricted periods. It’s also possible that caffeine intake could lead to spontaneous fat loss in some individuals, as increased energy might result in more energy expenditure. It’s important to note that not everyone will respond to caffeine this way, but this is the most intuitive way caffeine could help in a fat loss plan.
Other mechanistic properties of caffeine could also positively affect body composition. For example, some suggest that caffeine can stimulate the activity of brown adipose tissue (BAT), which could lead to an increase in energy expenditure. While an energy deficit would be needed to aid in any significant changes in body composition, caffeine could also have a small effect on fat mobilization. Lastly, it’s also possible that caffeine could give you enough energy to hit a training session when you might otherwise skip it, inadvertently providing an energy source to help you knock out some lifts.
Overall, caffeine could help your body composition in many ways, but the most common is providing Calorie-free energy during periods of reduced energy intake.
Mid-tier supplements for body composition
HMB
HMB (beta-hydroxy-beta-methylbutyrate) is a compound derived from the amino acid leucine, which stimulates muscle growth. HMB is typically taken in powdered or capsule form, and most studies show that the ideal benefits will be around a 3g dose. Common forms include HMB-Ca and HMB-FA. While some research suggests the bioavailability of HMB-FA has an edge, other studies suggest their end effects seem comparable. Both are fine options, so let your budget and ease guide here.
Now, let’s get into what HMB could do.
From what we can see, HBM seems ideal for protecting against muscle damage. So, if you think of leucine as stimulating muscle protein synthesis, you can think of HMB as reducing muscle breakdown. Where would this be most relevant? If you’re new to lifting, getting back into lifting after a long period off, or lifting during a deficit where you’re more vulnerable to catabolic states, HMB could be something you consider.
For example, one of the populations most vulnerable to muscle degeneration is older and elderly individuals. A systematic review that examined HMB and body composition in elderly populations found that HMB supplementation works well for helping older adults hold onto muscle and strength, even if they’re bedridden or inactive. Studies examining varying populations and sexes found similar anti-catabolic effects and protection in untrained lifters. With that said, there would seem to be less impressive results when the individuals are trained or competitive athletes.
One fair question when discussing HMB is whether you even need it if you’re already consuming enough protein or leucine (because HMB is a metabolite of leucine). Could you just rely on getting enough protein or taking leucine directly? The evidence isn’t entirely there yet, but there does seem to be something there with HMB as a muscle-wasting protectant. The good thing is that other than the smell and taste, side effects seem to be pretty minimal.
Betaine
Betaine is a “zwitterionic quaternary ammonium compound,” which is fancy chem speak for a compound that comes from sugar beets, though it can also be found in other foods such as spinach or seafood. Dosing typically starts around 2.5g, and studies haven’t shown notable side effects at this level. However, higher doses (above 9g) could potentially affect blood lipids, so it’s important to be mindful of dosage when supplementing.
From the first article, I discussed another beet-derived supplement, where the primary action mechanism is nitric oxide, improving blood flow and nutrient delivery. Betaine, however, works through different mechanisms for body composition. One possible pathway is that betaine may influence enzymes that break down fat. Betaine can also lower homocysteine, which can help kick start fat breakdown.
A meta-analysis by Gao et al found that betaine supplementation reduced total body fat and body fat percentage, though it had minimal effects on overall body weight or BMI. There were indications of increased lean mass as well. The analysis also noted that betaine supplementation resulted in greater fat reductions when combined with exercise. When viewed in the right context, these findings suggest that betaine holds promise for improving body composition.
With all this said, the evidence on betaine is still mixed. A meta-analysis by Ashtary-Larky et al found that its effects on body composition were not as impressive. So, we are still learning, but there is promise.
In the end, supplements should be viewed as aids to support your changes rather than as magical solutions for body composition changes. That’s a controversial take at times, but the reality is that supplements are most effective when they complement what you’re already doing. This is particularly true for body composition, where gaining muscle requires focused resistance training, and losing fat necessitates a Calorie deficit. Those core actions are going to matter the most.
TL;DR for body composition supplements
Achieving noticeable improvements in body composition ultimately depends on your goals and program set-ups, such as maintaining a consistent Calorie deficit for fat loss or adding resistance training for muscle gain. However, these supplements may help support or make achieving those goals easier.
- Protein supplements: Helpful for building muscle or maintaining lean mass, especially when meeting daily protein needs during a Calorie deficit.
- Creatine: Effective for increasing lean body mass and supporting energy during Calorie deficits.
- Caffeine: Can provide energy during times of restriction, supporting overall training performance.
- HMB: Beneficial for those new to training, returning after a break, or doing more aggressive cuts.
- Betaine: Could assist in fat breakdown, though a Calorie deficit is still needed for significant changes.
