Daily How Much

For collagen supplements, most adults take 2.5–10 g per day; specific study ranges vary by goal and product type.

Most adults need 150 mcg of iodine per day; pregnancy needs 220 mcg, lactation 290 mcg, and the adult upper limit is 1,100 mcg.

Most adults do well with 1–10 billion CFU probiotics daily; the right dose depends on strain, label guidance, and your reason for taking them.

Adults 19–50 need 1,000 mg of calcium daily; women 51+ and men 71+ need 1,200 mg, with supplements only to fill a real gap.

Daily iron needs range from 8–18 mg for most adults, 27 mg in pregnancy, with a 45 mg upper limit unless your clinician prescribes more.

Most adults need 2.4 mcg of vitamin B12 per day; pregnancy needs 2.6 mcg and lactation 2.8 mcg, from food or supplements.

Most healthy adults need 3,400 mg (men) or 2,600 mg (women) of potassium per day from food; needs vary by age and life stage.

Adults should stay under 2,300 mg of sodium per day; many benefit from a 1,500 mg goal, based on health needs and advice.

After exercise, drink 16–24 oz (475–710 mL) of water per pound (0.45 kg) of body weight lost within 2–6 hours, with sodium if sweat was heavy.

Most adults need about 1.3 g/kg protein while breastfeeding—roughly 25 g more per day than nonpregnancy needs.