I write about supplements professionally and have spent 20 years inside the industry reviewing them. My honest position, which might surprise people who find Wise Intake through supplement content, is that most people most of the time would benefit more from improving their diet than from adding supplements. Supplements have their place — a well-defined, specific place — but that place is smaller and more conditional than the supplement industry’s marketing suggests.

Here’s where the genuine cases for supplementation are, and where food wins by a margin wide enough to make a pill unnecessary.

Where supplements genuinely make sense

Vitamin D3, for almost everyone in northern latitudes. Vitamin D synthesis requires UVB radiation on skin. In winter months above about 37° latitude, the sun’s angle prevents meaningful UVB from reaching the surface. Office workers, people with darker skin (who need more sun exposure for equivalent synthesis), and those with limited outdoor time can have genuinely inadequate vitamin D from sun exposure alone. Food sources (oily fish, egg yolks, fortified foods) provide some but rarely enough to correct a deficiency. This is probably the strongest case for supplementation across the broadest population: the deficiency is widespread, the mechanism is clear, the safe effective dose is established.

Vitamin B12, for plant-based eaters and older adults. B12 is found almost exclusively in animal products. Vegans and vegetarians have essentially no reliable dietary source other than fortified foods (which vary in form and quantity). Older adults absorb B12 less efficiently as stomach acid decreases with age. B12 deficiency has serious consequences; supplementation is the straightforward solution. This is a case where a pill genuinely substitutes for what food doesn’t or can’t provide.

Folate, during pregnancy planning and early pregnancy. The evidence for folic acid (or preferably methylfolate) reducing neural tube defect risk is among the strongest in all of nutritional medicine. This is a case where supplementation provides a benefit food alone cannot reliably guarantee, because achieving the research-supported protective dose from diet alone is difficult.

Iodine, for plant-based eaters avoiding dairy and fish. Iodine deficiency is reemerging in populations avoiding dairy and not eating seafood, particularly relevant for thyroid function. Where diet doesn’t reliably cover iodine, supplementation is sensible.

Where food wins, reliably

Antioxidants. Decades of research on isolated antioxidant supplements (beta-carotene, vitamin E in high doses, vitamin C above adequate) has consistently failed to reproduce the health outcomes associated with whole-food antioxidant intake. Worse, some supplemental antioxidants in high doses have shown adverse effects in specific populations. The food matrix — the combination of fibre, phytonutrients, vitamins, and minerals in whole plants — produces outcomes that isolated supplements don’t replicate. Eat the vegetables.

Omega-3 for people who eat oily fish regularly. For those eating fatty fish two or more times per week, supplemental omega-3 adds little of measurable benefit. The supplement case strengthens for people who don’t eat fish — it substitutes for what the diet lacks.

Most minerals in adequate diets. Zinc, magnesium, calcium, selenium, and most other minerals are achievable through a varied diet that includes legumes, nuts, seeds, whole grains, and animal products. Supplementing these without testing for deficiency adds cost and the small risk of excess over time.

The honest synthesis

Take the short list seriously — D3 if you’re not getting sun, B12 if you’re plant-based or older, folate around pregnancy. These are evidence-based, targeted, and genuinely difficult to achieve through food in the relevant circumstances. For everything else: the evidence consistently suggests that improving dietary variety and quality produces broader and more lasting benefit than adding pills. The supplement industry’s implicit message that most people have gaps only supplements can fill is commercially motivated, not evidence-based.