Clear, science-based guides on calories, vitamins, and minerals — written to help you actually use your DRI results.
The 500-kcal deficit explained, why your vitamin and mineral needs don't drop when you eat less, and how to lose fat without depletion.
Read article → ConceptsDietary Reference Intake explained simply — the four values (EAR, RDA, AI, UL) and how your needs change by age, sex, and life stage.
Read article → ConceptsDRI is the umbrella, RDA is one value inside it. Here's what each term means and which number you should actually follow.
Read article → PregnancyIron, folate, calcium, calories, and protein — exactly how your nutrient needs change each trimester, sourced directly from NASEM data.
Read article → ReferenceFull RDA, AI, and UL values for every vitamin, mineral, and macronutrient — sorted by age, sex, and life stage. Sourced from NASEM.
Read article → NutrientsExact iron mg needed for men, women, pregnancy, and kids. Iron-rich foods, absorption tips, anemia signs, and supplement guidance — all in one guide.
Read article → Nutrients600 IU for adults, 800 IU after 70, 4,000 IU upper limit. Deficiency signs, D2 vs D3, food and sun sources — your complete vitamin D guide.
Read article → Life StagesMore calories, more zinc, far less iron than women — see the full DRI for men by age, with exact calorie, vitamin, and mineral targets in one chart.
Read article → Life StagesIron, calcium, folate, and calorie targets for women from the teen years through menopause — the full female lifecycle DRI in one guide.
Read article → NutrientsCalcium needs from infancy to 70+, the best food sources, the 500 mg absorption rule most people miss, and how much is too much.
Read article → Life StagesWhat rises and what falls after 50 — calcium, vitamin D, and B12 up, calories down, and why the protein RDA may be too low for seniors.
Read article → NutrientsHow many grams of protein you need by weight and goal — for muscle, weight loss, or health — plus how much per meal and the best sources.
Read article → Life StagesWhy teen nutrient needs peak — the calorie, calcium, iron, and protein targets for ages 9–18, by age and sex, plus the most common gaps.
Read article → NutrientsMagnesium needs by age and sex, the best food sources, why the supplement limit sits below the RDA, and the signs of low magnesium.
Read article → NutrientsPotassium needs by age and sex, why you see 4,700 vs 3,400 mg, the sodium balance for blood pressure, and the best foods — beyond bananas.
Read article → NutrientsHow much B12 you need by age, the best food sources, why supplements are 500 mcg when you need just 2.4, B12 for vegans, and deficiency signs.
Read article → NutrientsZinc needs by age and sex, the best food sources, the zinc-copper balance behind the 40 mg limit, and the honest truth about zinc for colds, skin, and testosterone.
Read article → NutrientsHow much fiber you need by age and sex, soluble vs insoluble explained, the best high-fiber foods, and how to add fiber without the bloating.
Read article → NutrientsWhy adults need 400 mcg DFE, what that confusing unit actually means, folate vs folic acid, and why timing matters before pregnancy.
Read article → Life StagesWhy carbohydrate, not protein, is the nutrient that really shifts with training — plus targets by training load, the 150% rehydration rule, and timing.
Read article → NutrientsWhy adults need just 90 mg, the reason mega doses are wasted, the best food sources beyond oranges, and the honest truth about vitamin C and colds.
Read article → NutrientsHow much vitamin A you need, what RAE and IU actually mean, retinol vs beta-carotene, and why you can't overdose on carrots but supplements can be risky.
Read article →Free, instant results — calories, macros, vitamins, and minerals for your profile.
Open the CalculatorAll values and formulas on this site trace back to authoritative, peer-reviewed sources.
