Supplements for Men Over 40: A Short, Honest List

The supplement industry sells men over 40 a great deal of nonsense. The list of things that genuinely help is short, unglamorous, and mostly the same list as for men over 30 — with a few real changes.

What actually changes

Muscle mass declines from roughly the third decade, at around 3 to 8% per decade, accelerating later. This is the change with the largest consequences for how you function at 70.

Anabolic resistance sets in. Older muscle responds less strongly to a given dose of protein, so both the per-meal dose and the daily total need to go up.

B12 absorption declines, as stomach acid production falls with age and with common medications.

Testosterone falls gradually — around 1% a year after 30 in most men. This is real, and it is also the hook for a great deal of ineffective marketing.

The list that earns its place

Protein — the one that matters most

Not glamorous, and more important than everything else here combined. Aim for 1.6 to 2.0 g per kg of body weight per day, spread across three or four meals rather than concentrated at dinner, with 30 g or more at each. Breakfast is where most men fall short.

Paired with resistance training twice a week, this is the intervention that changes how the next thirty years go.

Creatine monohydrate

3 to 5 g daily. The best-evidenced supplement in sports nutrition, and the evidence in older adults is if anything stronger than in younger ones — it supports strength and lean mass alongside training. Inexpensive, well studied, and the plain monohydrate is all you need.

Vitamin D

Test it. Correct it if it is low. Involved in muscle function, bone and immune regulation, and genuinely common to be short of.

Omega-3

If you do not eat oily fish twice a week. Read the EPA and DHA numbers on the back rather than the “1000 mg” on the front.

Magnesium

Commonly low, with reasonable evidence for blood pressure and sleep. Choose glycinate or citrate, not oxide.

B12

Worth checking after 50, and worth checking sooner if you take metformin or a proton pump inhibitor, both of which interfere with absorption.

What to avoid

Testosterone boosters. As a category, these do not work. Systematic reviews of the common ingredients — tribulus, fenugreek, D-aspartic acid, ashwagandha for this purpose — find little or no meaningful effect on testosterone in men with normal levels. Zinc and vitamin D matter if you are deficient in them, which is a different claim entirely. If you genuinely suspect low testosterone, that is a blood test and a doctor, not a tub.

Iron, unless tested and low. Men do not lose iron monthly and should not take it routinely. Iron deficiency in an adult man is a reason to find out why, not to supplement.

Prostate blends. The evidence for saw palmetto in benign prostatic hyperplasia is weak, with the better-controlled trials showing little benefit over placebo. Prostate symptoms warrant a doctor rather than a supplement aisle.

Megadose antioxidants. High-dose vitamin E has shown harm in some trials, and there is evidence that heavy antioxidant supplementation can blunt some training adaptations, which are partly driven by oxidative signalling.

The honest summary

Eat enough protein. Lift weights twice a week. Take creatine. Get vitamin D and B12 tested. Sleep. Everything else on this list is a rounding error by comparison, and everything on the avoid list is worse than a rounding error.