Nutrition

• How much water should you drink a day?

  The National Academies suggest about 3.7 liters of total water a day for men and 2.7 liters for women, of which about 80% comes from drinks. What that means in cups, and when you need more.

• Salmon nutrition: protein, omega-3 and wild vs farmed

  A 3.5 oz (100 g) portion of cooked salmon has about 180-210 calories, 22-25 g protein and about 2 g of omega-3 fats. Compare wild and farmed salmon and how much to eat.

• Saturated vs unsaturated fat: what is the difference?

  Saturated fat is solid at room temperature and raises LDL cholesterol; unsaturated fat is liquid and can lower it. Daily limits, food examples and label tips.

• Peanut butter nutrition: calories in 1 and 2 tablespoons

  Two tablespoons of peanut butter have about 190 calories, 7 g protein and 16 g fat. See the calories per tablespoon, natural vs regular, and how it compares with almond butter.

• Sweet potato vs white potato: which is healthier?

  Sweet and white potatoes have almost the same calories. Sweet potatoes have far more vitamin A and a little more fiber, while white potatoes have more potassium. Full comparison.

• Greek yogurt vs regular yogurt: nutrition compared

  Greek yogurt has about twice the protein and half the carbs of regular yogurt, while regular yogurt has more calcium. Side-by-side nutrition and which to choose.

• Quinoa vs rice: calories, protein and fiber compared

  Per cup cooked, quinoa has about 222 calories, 8 g protein and 5 g fiber, compared with 205 calories, 4 g protein and under 1 g fiber for white rice. Full comparison with brown rice.

• How much sodium per day? Limits and salt conversions

  The Daily Value for sodium is 2,300 mg, about one teaspoon of salt. See sodium vs salt conversions, the foods that supply the most, and how to cut back.

• Oatmeal nutrition facts: calories, protein and fiber

  Half a cup of dry rolled oats has about 150 calories, 5 g protein and 4 g fiber. Compare rolled, steel-cut and instant oats, and see why oats are good for cholesterol.

• How many grams of sugar per day? Added sugar limits

  The food label Daily Value for added sugars is 50 g, the AHA suggests 25 g for women and 36 g for men, and the new Dietary Guidelines cap it at 10 g per meal. Here is how to use each.

• How much fiber per day? Targets and high-fiber foods

  Adults need about 25 to 38 grams of fiber a day, and the Daily Value is 28 g. See targets by age and sex, a high-fiber food chart and how to add fiber without discomfort.

• Are food preservatives bad for you? What the evidence says

  Most approved food preservatives are safe at the levels used. Here is what each common type does, which ones have real concerns, and how to spot them on a label.

• How much protein do you need per day? (by weight)

  The RDA is 0.8 g of protein per kg of body weight, and the 2025-2030 Dietary Guidelines suggest 1.2 to 1.6 g/kg. See grams per day by weight, with food examples.

• Rice calories: cooked vs uncooked, white and brown

  Cooked white rice has about 130 calories per 100 g, uncooked about 365. Learn why and how to count rice correctly.

• Net carbs vs total carbs: what is the difference?

  Net carbs are usually total carbohydrate minus fiber. Learn how to calculate them, why the term is not official, and examples with real foods.

• How to read a nutrition facts label (US)

  A plain guide to the US nutrition facts label: serving size, calories, % Daily Value, added sugars and how to compare products.

• How much protein is in an egg? Size, white and yolk

  A large egg has about 6 grams of protein. See protein and calories for every egg size, plus the white and yolk separately.

• How many calories are in an avocado?

  Avocado has about 160 calories per 100 g. See calories for a third, half and whole avocado, plus the fat, fiber and potassium.

• How many calories are in an apple? By size

  A medium apple has about 95 calories. See calories, fiber and sugar for small, medium and large apples.

• How many calories are in a banana? By size

  A medium banana has about 105 calories. See calories, carbs, fiber and potassium for every banana size, plus the per 100 g figures.

• How are calories calculated? Protein, carbs and fat

  Calories come from protein, carbohydrate, fat and alcohol. Learn the 4-4-9 rule, why it only approximates food labels, and a worked example.

• High-protein foods: protein per 100 g compared

  Compare the protein and calories in 100 g of chicken, tuna, salmon, eggs, nuts, cheese, yogurt and beans, and how to read the numbers fairly.

• Chicken breast: raw vs cooked calories and protein

  Raw chicken breast has about 120 calories per 100 g and cooked has about 165. Here is why the numbers differ and which one to use.