Micronutrients Explained

Micronutrients rarely announce themselves. You notice them mainly through their absence, and shortfalls tend to develop slowly rather than dramatically.

Vitamins

Fat-soluble vitamins A, D, E, and K are absorbed with dietary fat and stored in the body. Water-soluble vitamins — the B group and vitamin C — are mostly not stored, so regular intake matters more.

Minerals

Minerals include calcium, iron, magnesium, zinc, potassium, iodine, and selenium. Some, such as iron, are absorbed differently depending on their form: haem iron from animal foods is absorbed more readily than non-haem iron from plants, though vitamin C eaten alongside plant sources improves absorption.

Common shortfalls

• Vitamin D — limited food sources and reduced skin synthesis in winter at higher latitudes; several national bodies advise supplementation during winter months.
• Iron — particularly relevant for people with heavy menstrual bleeding and for some plant-based diets.
• Vitamin B12 — found almost exclusively in animal foods and fortified products; supplementation is standard advice on a vegan diet.
• Iodine — intake depends heavily on local food supply and salt fortification policy.

Food first, supplements where indicated

A varied diet covers most micronutrient needs. Supplements are useful where a genuine gap exists — established by diet, circumstance, or a blood test — rather than as general insurance. More is not better: several micronutrients have defined upper limits.