THE SUPPLEMENT INDUSTRY DOESN'T WANT YOU TO KNOW THESE FOUR THINGS ACTUALLY WORK

The supplement industry is one of the most profitable and most misleading industries on earth — a multi-hundred-billion-dollar global market built largely on marketing, loose regulation, and the universal desire to find a shortcut to health. Most supplements on the market either don't work, work minimally, or haven't been adequately tested in humans to know whether they work at all.

This is not a chapter telling you to buy a stack of fifteen products. It's a short list of what actually has evidence behind it, what dose the research supports, and what's overhyped enough to skip entirely.

The Foundation Four — Non-Negotiable After 50

Creatine monohydrate. The single most evidence-supported performance and longevity supplement available, full stop. Combined with resistance training, creatine consistently produces meaningful improvements in muscle mass, strength, and functional performance in older adults — and a 2018 meta-analysis found it also improved memory and cognitive performance, with the effect particularly pronounced in older adults. The brain uses creatine as an energy buffer the same way muscle does. It has been studied in humans for over 30 years, and concerns about kidney damage in healthy adults at standard doses haven't held up. Dose: 3 to 5 grams daily, monohydrate specifically — not HCl, not buffered, not a proprietary blend. Monohydrate has the evidence base; everything else is marketing.

Omega-3s — EPA and DHA. One of the longest, most consistent evidence bases in nutrition science. For active people over 50: anti-inflammatory support for joints and recovery, cardiovascular protection, and — per a 2025 Nature Aging analysis of the DO-HEALTH trial — measurably slower biological aging markers when combined with vitamin D and exercise. Dose: 1 to 3 grams combined EPA plus DHA daily, from fish oil, krill oil, or algae-based sources if avoiding animal products.

Vitamin D3. An estimated 40 percent of adults in the United States are deficient, higher in northern latitudes during winter. D3 functions more like a hormone than a vitamin — regulating calcium absorption, immune function, and muscle protein synthesis. Low levels in older adults track with higher rates of sarcopenia, falls, and all-cause mortality. Dose: 2,000 to 4,000 IU daily, ideally guided by an actual blood test rather than a guess — target 40 to 60 ng/mL. Pair with vitamin K2 (MK-7, 100–200 mcg) to help direct that calcium to bone instead of arteries.

Magnesium glycinate. Involved in over 300 enzymatic reactions, and over half of Americans don't get enough from diet alone. A 2012 randomized controlled trial found magnesium supplementation significantly improved sleep onset, duration, efficiency, and morning cortisol in older adults versus placebo. Dose: 200 to 400 mg of the glycinate form, 30 to 60 minutes before bed.

The Second Tier — Strong Evidence, Use If It Fits Your Situation

CoQ10 (ubiquinol form): particularly relevant if you take a statin, since statins deplete CoQ10 as part of how they work. Collagen peptides (10–15g pre-training with vitamin C) for joint and connective tissue support. Berberine for blood sugar — multiple meta-analyses show reductions in fasting glucose and HbA1c comparable to metformin, without the GI side effects, though it can interact with several prescription medications. Ashwagandha (KSM-66) for cortisol and recovery — a 2015 study in the Journal of the International Society of Sports Nutrition found athletes on KSM-66 saw significantly greater strength and recovery gains over eight weeks versus placebo. Urolithin A for mitochondrial function in older adults, per a 2022 trial — newer and pricier, worth approaching as an addition rather than a requirement.

The Overhyped — Save Your Money

NMN and NR ("NAD+ boosters") have a sound theory but human evidence that doesn't yet justify the price tag. Resveratrol has failed to show meaningful benefit in multiple well-designed human trials — eat the grapes, skip the pill. And any company selling a 10-to-20-ingredient "complete longevity stack" is almost certainly prioritizing margin over evidence; individual, well-dosed supplements outperform proprietary blends in virtually every rigorous comparison.

Supplements supplement a great diet and training program. They do not replace one.

The Bottom Line

Start with the Foundation Four. Add the second tier one item at a time, over months, never multiple at once — if something helps or hurts, you need to know which one did it. Trust built on telling you what doesn't work is worth more than any commission on what does.