Which Supplements Actually Work?

Which Supplements Actually Work? (A No-BS Guide Based on Research)

TL;DR: Of the hundreds of supplements marketed to build muscle, boost testosterone, and improve performance, only a handful have solid evidence behind them. Creatine works. Protein works (if you're not getting enough from food). Everything else ranges from 'maybe helpful in specific situations' to 'complete waste of money.' This guide tells you which is which.

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The Short Answer

Worth your money:

• Creatine monohydrate (strong evidence)
• Protein powder (if diet is lacking)
• Vitamin D (if deficient)
• Omega-3 fish oil (for recovery, general health)

Situational/marginal:

• Beta-alanine (for high-intensity endurance, 1-4 min efforts)
• Caffeine (pre-workout performance, but you already know this)
• Ashwagandha (stress/cortisol, modest testosterone effect)

Probably not worth it:

• BCAAs (redundant if eating protein)
• Most "testosterone boosters"
• Tribulus terrestris
• Most pre-workout proprietary blends

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The Supplement Industry's Dirty Secret

The global sports nutrition market is worth over $50 billion. Most of that money is spent on products with little to no scientific evidence.

Here's how the industry works:

1. Cherry-pick a study - usually in rats, or a tiny human trial with bad methodology
2. Create marketing claims - "clinically proven" (technically true, just not proven to work)
3. Proprietary blends - hide the actual doses so you can't verify anything
4. Before/after photos - often the same person with different lighting, pump, and tan

A 2020 analysis of the 50 most popular "testosterone boosters" on Google found that 61.5% of the 109 ingredients had ZERO studies on their effect on testosterone. Of the rest, only 24.8% had any data showing they might increase testosterone - and 10.1% had data suggesting they decrease it.¹

You're literally gambling with your money.

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Tier 1: Actually Works (Strong Evidence)

Creatine Monohydrate

Verdict: BUY IT

Creatine is the most studied sports supplement in history. It works. Here's what the research says:

What it does:

• Increases muscle phosphocreatine stores by 20-40%
• Provides more fuel for high-intensity, short-duration efforts
• Enhances training volume and recovery

What the studies show:

• A 2024 meta-analysis of 23 studies found creatine + resistance training increased upper-body strength by 4.4 kg and lower-body strength by 11.4 kg compared to training alone²
• Creatine combined with resistance training increases lean body mass by 1.1-1.5 kg in adults regardless of age³
• Benefits are greater in males than females (possibly due to females having higher baseline muscle creatine levels)

How to take it:

• 3-5g per day, every day (loading phase optional but not necessary)
• Any time of day - consistency matters more than timing
• Creatine monohydrate is the most researched form; fancy versions aren't better

Side effects:

• May cause 1-3 lbs of water retention initially
• No evidence of kidney damage in healthy individuals
• Safe for long-term use

Cost: ~$0.05 per day for a quality product

Protein Powder

Verdict: USEFUL (IF NEEDED)

Protein powder isn't magic - it's just convenient protein. The question isn't whether protein builds muscle (it does), but whether you need it in supplement form.

When it's worth it:

• You struggle to hit protein targets through food (see our protein article)
• Convenience matters (travel, post-workout, busy schedule)
• You need a high-protein, low-calorie option

When it's NOT worth it:

• You're already eating 1.2-1.6 g/kg of protein from food
• You think it's fundamentally different from chicken or eggs (it's not)

Best types:

• Whey protein: Fast-absorbing, complete amino acid profile, well-studied
• Casein: Slower-absorbing, good before bed
• Plant-based blends: Fine if you can't do dairy, but check amino acid profile

The research: A 2017 meta-analysis of 49 studies with nearly 2,000 participants found protein supplementation increased fat-free mass by 0.75 kg compared to placebo in trained lifters - but only when total protein intake was below 1.6 g/kg/day. Above that, no additional benefit.⁴

Translation: Protein supplements help if you're not eating enough protein. If you are, they're expensive chicken.

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Tier 2: Works in Specific Situations

Vitamin D

Verdict: TEST FIRST, SUPPLEMENT IF DEFICIENT

Vitamin D isn't a performance supplement - it's a hormone precursor that millions of people are deficient in, especially if you:

• Live north of the 37th parallel (most of the US, all of Europe)
• Work indoors
• Have darker skin
• Are over 40

What the research shows:

• Deficiency is associated with lower testosterone levels⁵
• Supplementation can increase testosterone in deficient men - one study showed significant increases with 3,332 IU daily for one year⁶
• However, supplementation does NOT increase testosterone in men with normal vitamin D levels⁷

The honest truth: Vitamin D supplementation only helps if you're deficient. If your levels are already adequate, taking more won't boost testosterone or performance.

How to know: Get a blood test. Optimal 25(OH)D levels are generally considered 30-50 ng/mL. If you're below 20 ng/mL, you're deficient.

If deficient:

• 2,000-5,000 IU daily is typical
• Take with fat for better absorption
• Retest in 2-3 months

Omega-3 Fish Oil (EPA/DHA)

Verdict: GOOD FOR RECOVERY AND HEALTH

Fish oil won't directly build muscle, but it may help you train harder by reducing inflammation and speeding recovery.

What the research shows:

• A 2024 meta-analysis found omega-3 supplementation reduces inflammatory markers (IL-6, TNF-α, CRP) after exercise-induced muscle damage⁸
• May reduce delayed-onset muscle soreness (DOMS)
• Has well-established benefits for cardiovascular health, brain function, and reducing chronic inflammation
• A 2020 meta-analysis found supplementing 2,000+ mg omega-3s for 6+ months improved walking speed and was associated with a 0.73 lb increase in muscle mass in elderly individuals⁹

Practical benefit: If you train hard and frequently, omega-3s may help you recover faster and train more consistently. The effect is modest but real, and the general health benefits make it worthwhile regardless.

How to take it:

• 2,000-3,000 mg combined EPA+DHA daily
• Look for products tested for purity (heavy metals, oxidation)
• Take with food

Beta-Alanine

Verdict: WORKS FOR SPECIFIC ACTIVITIES

Beta-alanine increases muscle carnosine, which buffers acid during high-intensity exercise. This delays the "burn" you feel during hard efforts.

What the research shows:

• The International Society of Sports Nutrition position stand confirms beta-alanine improves exercise performance, particularly in efforts lasting 1-4 minutes¹⁰
• Less clear benefit for shorter (<1 min) or longer (>10 min) efforts
• 4-6g daily for 4+ weeks needed to see effects

Who benefits:

• Crossfit athletes
• Rowers
• 400-800m runners
• Anyone doing high-rep, high-intensity sets

Who probably doesn't benefit:

• Powerlifters (efforts too short)
• Marathon runners (efforts too long)
• Casual gym-goers doing 8-12 rep sets

Side effect: Beta-alanine causes paresthesia - a harmless tingling sensation, usually in the face, neck, and hands. It starts 10-20 minutes after ingestion and fades within an hour. Taking smaller doses (0.8-1.6g) multiple times daily reduces this.

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Tier 3: Might Help, Might Not

Ashwagandha

Verdict: MODEST EVIDENCE FOR STRESS AND TESTOSTERONE

Ashwagandha (Withania somnifera) is an adaptogen that's been used in Ayurvedic medicine for centuries. Recent research suggests it may have real effects on stress, cortisol, and testosterone.

What the research shows:

• A 2020 systematic review found ashwagandha root and root/leaf extracts have positive effects on testosterone concentrations in men¹¹
• May work partly by reducing cortisol (stress hormone), which is inversely correlated with testosterone
• One 8-week study found ashwagandha supplementation increased testosterone AND muscle strength in men doing resistance training¹²

The caveats:

• Effects are modest - we're talking maybe 10-15% increase in testosterone, not dramatic changes
• Studies use varying doses, extracts, and standardization
• Won't overcome poor sleep, chronic stress, or obesity

If you try it:

• 300-600mg of root extract daily (KSM-66 and Sensoril are well-studied extracts)
• May take 8-12 weeks to see effects

Fenugreek

Verdict: SOME POSITIVE DATA, NOT CONCLUSIVE

Fenugreek seed extract appears in many testosterone boosters and has more research behind it than most ingredients.

What the research shows:

• A 2020 meta-analysis found fenugreek supplementation resulted in a significant increase in testosterone¹³
• Some studies show 500-600mg for 8-12 weeks increased testosterone by 12-46%
• May work by inhibiting enzymes that convert testosterone to estrogen

The caveats:

• Many studies were funded by companies selling fenugreek products
• Results vary widely between studies
• Real-world effect on muscle building is unclear

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Tier 4: Probably Waste Your Money

BCAAs (Branched-Chain Amino Acids)

Verdict: SKIP IT

BCAAs are three amino acids - leucine, isoleucine, and valine - that are important for muscle building. The supplement industry has spent decades convincing people they need to buy them separately.

Here's the problem:

BCAAs are already in every protein source you eat. Whey protein, chicken, eggs, beef - they all contain BCAAs. If you're eating adequate protein, you're already getting plenty of BCAAs.

What the research actually shows:

A landmark study from the University of Stirling found that while BCAAs stimulate muscle protein synthesis, the response was more than double when subjects took whey protein with the same amount of BCAAs plus the other essential amino acids.¹⁴

Professor Kevin Tipton, who led the research, stated: "Our results show that the common practice of taking BCAA supplements in isolation will stimulate muscle protein synthesis - but the total response will not be maximal because BCAA supplements do not provide other amino acids essential for the best response."¹⁵

Translation: BCAAs are the equivalent of buying three wheels for your car and wondering why it doesn't drive well.

A review in the Journal of the International Society of Sports Nutrition concluded: "The claim that consumption of dietary BCAAs stimulates muscle protein synthesis or produces an anabolic response in human subjects is unwarranted."¹⁶

If you're already eating enough protein: BCAAs are redundant. If you're NOT eating enough protein: Buy protein powder or eat more food.

Most "Testosterone Boosters"

Verdict: BUYER BEWARE

The testosterone booster market is largely built on hope and marketing, not science.

What the research shows:

A comprehensive analysis of 50 popular testosterone boosters found:¹

• Average of 8.3 ingredients per product
• 61.5% of ingredients had NO studies on testosterone
• Only 24.8% had data supporting a testosterone increase
• 10.1% had data suggesting they DECREASE testosterone
• Many contained vitamins at 800-1,200% of daily recommended values

Tribulus terrestris - one of the most common ingredients - has been specifically evaluated in systematic reviews and found ineffective at increasing testosterone in humans.¹⁷

What might actually help (if you're low):

• Sleep (7-9 hours)
• Weight loss (if overweight)
• Stress management
• Fixing vitamin D or zinc deficiency
• Strength training

These free interventions likely have bigger effects than any supplement.

Pre-Workout Proprietary Blends

Verdict: OFTEN UNDERDOSED GARBAGE

Pre-workouts can work - but most use "proprietary blends" that hide the actual doses of each ingredient. This lets them list impressive ingredients on the label while including dust-level amounts.

The problem:

• Creatine needs 3-5g to work - many pre-workouts contain 1g or less
• Beta-alanine needs 4-6g daily - many contain 0.5-1g
• The tingling you feel is often from niacin or minimal beta-alanine, not actual performance ingredients

If you want pre-workout benefits:

• Buy creatine separately
• Buy beta-alanine separately (if relevant to your training)
• Drink coffee for caffeine

This approach is cheaper, lets you control doses, and you know exactly what you're taking.

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The Supplement Decision Framework

Before buying any supplement, ask:

1. Is there strong evidence it works?

• Look for multiple randomized controlled trials in humans
• Meta-analyses and systematic reviews are better than single studies
• Check if studies were funded by the supplement company

2. Am I deficient in this?

• Many supplements only work if you're deficient (vitamin D, zinc, magnesium)
• If your diet is adequate, supplementing won't provide extra benefit

3. Is the dose in the product actually effective?

• Compare to doses used in research
• Watch for proprietary blends that hide actual amounts

4. What's the cost-benefit?

• Some supplements work but the effect is tiny
• Is 5% better worth $50/month?

5. Could I get this from food instead?

• Often cheaper and comes with additional nutrients
• Food-based protein, omega-3s from fish, etc.

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The Bottom Line

Supplement	Verdict	Notes
Creatine monohydrate	✅ Buy	Strong evidence, cheap, safe
Protein powder	✅ If needed	Helpful if diet falls short
Vitamin D	✅ If deficient	Test levels first
Omega-3 fish oil	✅ Recommended	Recovery + health benefits
Beta-alanine	⚠️ Situational	Only for 1-4 min high-intensity
Caffeine	⚠️ Works	But you don't need a supplement
Ashwagandha	⚠️ Maybe	Modest effects, worth trying
Fenugreek	⚠️ Maybe	Some evidence, not conclusive
BCAAs	❌ Skip	Redundant if eating protein
Tribulus	❌ Skip	Doesn't increase testosterone
Most test boosters	❌ Skip	Marketing > science
Proprietary blends	❌ Skip	Usually underdosed

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Find Out What You Actually Need

Stop guessing. Stop wasting money on supplements that don't work.

→ Try the Supplement Filter

Enter the supplements you're considering. Get verdicts based on actual research - not marketing claims or bro-science. See what's worth your money and what's going straight down the toilet.

Takes 2 minutes. Might save you hundreds of dollars.

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FAQ

What about ZMA (Zinc, Magnesium, B6)?

ZMA can help - but only if you're deficient in zinc or magnesium. Many athletes do have suboptimal levels due to losses through sweat. However, ZMA won't boost testosterone above normal levels. If you're not deficient, it won't help.

Should I take a multivitamin?

Multivitamins are insurance against deficiencies, not performance enhancers. If your diet is varied and includes vegetables, fruits, and protein sources, you probably don't need one. If your diet is limited or you're cutting calories, a basic multi is fine but not magical.

What about glutamine?

Glutamine was popular in the 90s-2000s but research has consistently failed to show benefits for muscle building or recovery in healthy, well-fed individuals. Save your money.

Are there any supplements that help with fat loss?

Caffeine increases metabolic rate modestly. Everything else - fat burners, thermogenics, "metabolic boosters" - either doesn't work or has effects too small to matter. The supplement industry LOVES selling fat loss products because they can always blame your diet when they don't work.

I saw [influencer] recommend [product]. Should I try it?

Ask yourself: Is this person being paid to recommend this? (Usually yes.) Did they actually use this to get their physique? (Often no - genetics, training, and sometimes PEDs did the work.) Is there research on this product specifically? (Usually no.) Be skeptical of anyone who has 10+ sponsored products.

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Last updated: January 2026

Phantom Wellness has no financial relationships with any supplement companies. We don't sell supplements. We just read the research so you don't have to.

Footnotes

1. Clemesha CG, et al. "'Testosterone Boosting' Supplements Composition and Claims Are not Supported by the Academic Literature." World J Mens Health. 2020;38(1):115-122. PMC ↩ ↩²

2. Fernández-Landa J, et al. "Effects of Creatine Supplementation and Resistance Training on Muscle Strength Gains in Adults <50 Years of Age: A Systematic Review and Meta-Analysis." Nutrients. 2024;16(21):3665. PubMed ↩

3. Forbes SC, et al. "Influence of age, sex, and type of exercise on the efficacy of creatine supplementation on lean body mass: A systematic review and meta-analysis of randomized clinical trials." Nutrition. 2022;103-104:111791. ScienceDirect ↩

4. Morton RW, et al. "A systematic review, meta-analysis and meta-regression of the effect of protein supplementation on resistance training-induced gains in muscle mass and strength in healthy adults." Br J Sports Med. 2018;52(6):376-384. ↩

5. Wehr E, et al. "Association of hypovitaminosis D with metabolic disturbances in polycystic ovary syndrome." Eur J Endocrinol. 2009. ↩

6. Pilz S, et al. "Effect of vitamin D supplementation on testosterone levels in men." Horm Metab Res. 2011;43(3):223-225. PubMed ↩

7. Heijboer AC, et al. "Vitamin D and Testosterone in Healthy Men: A Randomized Controlled Trial." J Clin Endocrinol Metab. 2017;102(11):4292-4302. PubMed ↩

8. Meta-analysis on omega-3 and exercise-induced inflammation. "Effect of omega-3 fatty acids supplementation on inflammatory markers following exercise-induced muscle damage." ScienceDirect. 2024. ↩

9. Omega-3 and muscle mass meta-analysis. "Omega-3 Fatty Acids Supplementation and Muscle Mass." 2020. ↩

10. Trexler ET, et al. "International society of sports nutrition position stand: Beta-Alanine." J Int Soc Sports Nutr. 2015;12:30. PMC ↩

11. Smith SJ, et al. "Examining the Effects of Herbs on Testosterone Concentrations in Men: A Systematic Review." Advances in Nutrition. 2021;12(3):744-765. PMC ↩

12. Wankhede S, et al. "Examining the effect of Withania somnifera supplementation on muscle strength and recovery: a randomized controlled trial." J Int Soc Sports Nutr. 2015;12:43. ↩

13. Rao A, et al. "Testofen, a specialised Trigonella foenum-graecum seed extract reduces age-related symptoms of androgen decrease, increases testosterone levels and improves sexual function in healthy aging males." Aging Male. 2016. ↩

14. Jackman SR, et al. "Branched-Chain Amino Acid Ingestion Stimulates Muscle Myofibrillar Protein Synthesis following Resistance Exercise in Humans." Front Physiol. 2017;8:390. ↩

15. University of Stirling. "Not all muscle building supplements are equal." ScienceDaily. July 2017. ↩

16. Wolfe RR. "Branched-chain amino acids and muscle protein synthesis in humans: myth or reality?" J Int Soc Sports Nutr. 2017;14:30. PMC ↩

17. Qureshi A, et al. "A systematic review on the herbal extract Tribulus terrestris and the roots of its putative aphrodisiac and performance enhancing effect." J Diet Suppl. 2014. ↩