Daily How Much

Most adults need 600 IU (15 mcg) of vitamin D daily; adults 71+ need 800 IU, and the safe upper limit for healthy adults is 4,000 IU.

To avoid dehydration, most adults do well with 2–4 liters of total water per day, then add more on hot days or during long, sweaty activity.

Aim for 1.1 g of protein per kilogram of body weight each day in pregnancy—about 71 g/day after the first trimester.

Pre-workout caffeine typically runs 150–300 mg per scoop; effective doses are 3–6 mg/kg taken about 30–60 minutes before training.

For muscle gain, aim for 1.6–2.2 g protein per kg per day, split into 0.4–0.55 g/kg per meal across 3–5 meals.

Daily protein intake starts at 0.8 g/kg of body weight, with 1.2–2.0 g/kg fitting most active adults.

Most adults need 22–34 grams of dietary fiber per day, or about 14 grams per 1,000 calories, depending on age and sex.

Drink 5–7 mL per kg of body weight 2–4 hours before your run; if urine stays dark, add 3–5 mL/kg about 2 hours before.

Most adults need about 400–800 mL of water per hour of exercise, adjusted for heat, sweat rate, and body size.

Most adults do well by drinking enough to keep urine pale and reaching about 2–2.5 liters of urine a day for kidney health.