The short version
- A 2017 review found no human studies quantifying the muscle protein synthesis response to orally ingested BCAAs alone, and concluded the claim that BCAAs produce an anabolic response in humans is unwarranted.
- In 31 adults randomised to glutamine or placebo during six weeks of resistance training, both groups raised squat one-rep max about 30% with no significant difference in strength, lean tissue mass or muscle protein degradation.
- In the general community trials of the Cochrane review, covering 10,708 participants, regular vitamin C did not reduce the risk of catching a cold (risk ratio 0.97, 95% CI 0.94 to 1.00), though it shortened colds by 8% in adults.
- The exception is heavy physical stress: in five trials in 598 marathon runners, skiers and soldiers, vitamin C halved the risk of developing a cold (risk ratio 0.48, 95% CI 0.35 to 0.64).
- The US Preventive Services Task Force recommends against beta carotene, concluding with moderate certainty that harms outweigh benefits, and against vitamin E, concluding there is no net benefit.
The supplement industry's business model is accumulation. Nothing ever comes off the shelf, because no brand has any incentive to tell you an item has finished being useful. So here is the list, ordered by how confidently we would drop each one, written by a company that sells some of the things on it.
Two ground rules. Nothing here is being called dangerous. And if a clinician prescribed something for a documented reason, it is not on this list — this is about discretionary spending, not treatment.
1. Branched-chain amino acids, if you already eat enough protein
This is the clearest cut in the category and we sell a BCAA product, so read that as you like.
The theoretical case fails before you get to the trials. As Wolfe set out in a 2017 review, muscle protein synthesis requires all the essential amino acids. If you take only the three branched-chain ones, the rest must come from breaking down existing muscle protein, which caps any theoretical increase in synthesis at roughly the difference between breakdown and synthesis — about 30%, and that is an over-estimate because obligatory oxidation of amino acids cannot be fully suppressed. The review found no human studies quantifying the muscle protein synthesis response to orally ingested BCAAs alone, and the two intravenous infusion studies that exist found BCAAs decreased both synthesis and breakdown. The conclusion was that the claim BCAAs produce an anabolic response in humans is unwarranted.
If your protein intake is adequate, whole protein already contains the BCAAs, in the company of the amino acids they need to be useful. This is the first thing we would cut, from anyone's stack, including a customer of ours.
2. Glutamine for training
Thirty-one adults aged 18 to 24 were randomised, double blind, to a large glutamine dose or maltodextrin placebo during six weeks of resistance training. Both groups improved: squat one-rep max rose about 30% and bench press about 14%. There was no significant difference between groups on strength, knee extension torque, lean tissue mass or a marker of muscle protein degradation. The authors concluded glutamine supplementation during resistance training has no significant effect on muscle performance, body composition or muscle protein degradation in young healthy adults.
Small trial, one population, and it has not been overturned by anything better in the two decades since.
3. Daily vitamin C taken to avoid getting sick
The Cochrane review here is large and precise, which is why the conclusion is worth stating exactly. Twenty-nine trial comparisons in 11,306 participants fed the incidence analysis. In the general community trials, covering 10,708 participants, regular vitamin C supplementation did not reduce the risk of catching a cold: pooled risk ratio 0.97 (95% CI 0.94 to 1.00).
It did shorten colds — by 8% in adults (3% to 12%) — but that is 8% of a week, taken every single day of the year to collect it. And in the seven therapeutic comparisons, where people started vitamin C after symptoms began, no consistent effect on duration or severity appeared.
There is one genuine exception the review identifies: in five trials in 598 marathon runners, skiers and soldiers on subarctic exercises, the pooled risk ratio for developing a cold was 0.48 (0.35 to 0.64). If you are doing something in that category, this is not your cut. If you are taking 1,000mg a day at a desk in November, it is. For a shorter cold, the zinc dose evidence is considerably stronger.
4. Antioxidant megadoses, specifically beta carotene and vitamin E
The US Preventive Services Task Force does not often recommend against a supplement. It does for these two. On beta carotene it concluded with moderate certainty that the harms outweigh the benefits for preventing cardiovascular disease or cancer. On vitamin E it concluded there is no net benefit. On multivitamins generally it issued an insufficient-evidence statement.
This is the rare case where cutting is not just about saving money.
5. Anything you cannot describe the job of
Not an evidence category — a housekeeping one, and usually the largest line item. Go through the shelf and, for each bottle, say out loud what it is for and what would tell you it is working. The ones where you cannot finish the sentence are the cut. It is usually several of them, and it is usually the detox, greens and general-wellness end of the shelf that fails the test.
What we would keep
Anything correcting a measured deficiency, at the dose that matches it. Creatine, which is the cheapest well-evidenced item in the entire category. Folic acid for anyone who could become pregnant. B12 on a vegan diet. And whatever survives the question of whether you need supplements at all when you ask it honestly.
One thing not to cut
Do not save money by switching to the cheapest unverified version of something you have decided to keep. When 30 immune-support products bought from a major online marketplace were analysed, 17 had inaccurate labels, 13 listed ingredients that could not be detected at all, and none carried a third-party certification seal. A cheap capsule containing nothing is not a saving.
What we'd actually tell you
Halve the number of items, not the dose of the ones that remain. Underdosing three good products to afford six mediocre ones is the most common way a stack becomes expensive and useless simultaneously.
Then set a date to review it again. Anything you have been taking for a year without being able to say what it did has answered the question.
Good questions
What supplement should I cut first if money is tight?
Branched-chain amino acids, if your protein intake is adequate. Whole protein already contains them alongside the other essential amino acids they need in order to do anything. A 2017 review found no human studies quantifying the response to oral BCAAs alone and concluded the anabolic claim is unwarranted. We sell a BCAA product and this is still our answer.
Is daily vitamin C worth taking to avoid colds?
Not for most people. In the Cochrane review's general community trials, covering 10,708 participants, regular vitamin C did not reduce the risk of catching a cold. It shortened colds by 8% in adults, which is 8% of about a week in exchange for taking it 365 days a year. The clear exception is people under heavy physical stress, where risk of a cold roughly halved.
Does glutamine help with recovery or muscle growth?
The trial evidence says no for healthy trainees. In a double-blind randomised study during six weeks of resistance training, glutamine produced no significant difference from placebo in strength, knee extension torque, lean tissue mass or a marker of muscle protein degradation. Both groups improved similarly because the training worked.
Which supplements are actually worth keeping?
Anything correcting a deficiency you have measured, at a dose matched to it. Creatine, which is the cheapest well-evidenced item in the category. Folic acid for anyone who could become pregnant, and B12 on a vegan diet. Beyond that, keep only what you can describe a job for, and set a date to review it.
Should I buy cheaper versions of the supplements I keep?
Not the unverified ones. In an analysis of 30 immune-support products bought online, 17 had inaccurate labels, 13 listed ingredients that could not be detected at all, and not one carried a third-party certification seal. A cheap capsule that contains nothing is not a saving. Cut the number of items rather than the quality of the ones you keep.
Is it better to take fewer supplements at full dose or more at half dose?
Fewer, at full dose. Underdosing several products so you can afford more of them is the most common way a stack becomes both expensive and useless. A supplement taken below the dose that was studied is not a smaller benefit, it is usually no benefit, and you lose the ability to judge whether it was ever working.
Sources
- Wolfe RR. Branched-chain amino acids and muscle protein synthesis in humans: myth or reality? J Int Soc Sports Nutr, 2017. View study
- Candow DG, Chilibeck PD, Burke DG, Davison KS, Smith-Palmer T. Effect of glutamine supplementation combined with resistance training in young adults. Eur J Appl Physiol, 2001. View study
- Hemilä H, Chalker E. Vitamin C for preventing and treating the common cold. Cochrane Database Syst Rev, 2013. View study
- US Preventive Services Task Force. Vitamin, Mineral, and Multivitamin Supplementation to Prevent Cardiovascular Disease and Cancer: US Preventive Services Task Force Recommendation Statement. JAMA, 2022. View study
- Crawford C, Avula B, Lindsey AT, et al. Analysis of Select Dietary Supplement Products Marketed to Support or Boost the Immune System. JAMA Netw Open, 2022. View study
These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease.
