Dietary supplements and vitamins: what you really need

In short: Most healthy people cover their needs with a varied diet; supplements make sense only for proven deficiency or special life situations, not as miracle cures.

In more detail: Advertising promises more energy, muscles, concentration with powders, capsules and gummies. Dietary supplements are legally foods, not medicines: they are not tested for effectiveness like drugs. Not medical advice.

In Depth

When supplementation can make sense

• Vitamin D in autumn/winter with little sun (recommendation/amount with a doctor, check blood level).
• Vitamin B12 with a vegan diet (mandatory supplement).
• Folic acid when trying to conceive/pregnancy.
• Iodine/iron only with proven deficiency (overdosing iron harms).
• Omega-3 (algae oil) with a vegan diet/little fish.
• Creatine (strength training) is proven effective but not necessary; with kidney problems consult a doctor.
• Pregnant, elderly, ill, taking medication: clarify medically (interactions!).

What mostly brings nothing

• Multivitamin preparations for healthy people: no proven benefit, expensive.
• High-dose single vitamins (A, E, beta-carotene in smokers) can harm; fat-soluble vitamins (A, D, E, K) accumulate.
• “Concentration/brain” pills, fat burners, testosterone boosters, detox: effectiveness not proven, partly contaminated/dangerous (doping agents, hidden stimulants).
• Energy shots/caffeine tablets: risk of overdose (see caffeine).
• Protein powder: just a convenient protein source; many reach the need with normal food (teenagers/healthy people about 0.8–1.2 g/kg, strength athletes up to ~1.6–2 g/kg).

Nutrition first

• Variety: vegetables/fruit (5 portions), whole grain, legumes, nuts, dairy/alternatives, fish, little processed/sugar.
• Sun (vitamin D) 10–20 min in summer.
• Sleep, exercise, enough drinking.
• Deficiency symptoms (tiredness, hair loss, pallor) are unspecific: first a blood count at the doctor, not on your own.
• Read studies critically: animal test/cell culture ≠ human; conflicts of interest (manufacturer), finfluencer discount codes.

Buying and law

• Quality: reputable manufacturer, batch number, ingredients/amounts clear, follow the dosage recommendation; mind maximum amounts.
• Advertising claims: only approved health claims (EU regulation); “cures/relieves disease” is forbidden.
• Online purchases from third countries: sometimes unapproved substances; athletes (doping): contamination risk → Cologne List.
• Report side effects (BVL/pharmacist).
• Value: a pack for €30 does not replace good nutrition.
• Children/teenagers: supplement only on a doctor’s advice.

See also: Caffeine and energy drinks, Fibre and protein, Cooking simply and cheaply