Your body needs roughly 30 essential nutrients every day, split into three categories: macronutrients (protein, carbs, and fat), vitamins, and minerals. The specific amounts depend on your age, sex, and activity level, but the core list is the same for nearly everyone. Here’s what you need and how much.
Calories and Macronutrients
Adult women generally need 1,600 to 2,400 calories per day, while men need 2,000 to 3,000. The younger and more active you are, the higher your needs. After age 60, calorie needs dip slightly: most women need 1,600 to 2,200, and most men need 2,000 to 2,600.
Those calories should come from a rough balance of three macronutrients:
- Carbohydrates: 45 to 65 percent of your daily calories. These are your body’s primary fuel source. Whole grains, fruits, vegetables, and legumes are the best options.
- Protein: 10 to 35 percent of calories. For a sedentary adult, that works out to about 0.8 grams per kilogram of body weight (roughly 55 grams for a 150-pound person). If you exercise regularly, aim for 1.1 to 1.5 grams per kilogram. If you lift weights seriously or train for endurance events, 1.2 to 1.7 grams per kilogram is the target.
- Fat: 20 to 35 percent of calories. Your body uses fat to absorb certain vitamins, build cell membranes, and produce hormones. Keep saturated fat below 10 percent of total calories.
Added sugars should also stay under 10 percent of your daily calories. For someone eating 2,000 calories, that’s no more than 50 grams, or about 12 teaspoons.
Essential Vitamins
The FDA sets a single “Daily Value” for food labels, which serves as a useful benchmark for most adults. Here are the 13 vitamins you need every day:
- Vitamin A: 900 mcg. Supports vision, immune function, and skin health. Found in sweet potatoes, carrots, spinach, and liver.
- Vitamin C: 90 mg. Helps with wound healing and immune defense, and it significantly boosts iron absorption when eaten alongside iron-rich foods.
- Vitamin D: 15 mcg (600 IU) for adults up to age 70, rising to 20 mcg (800 IU) after 70. Critical for calcium absorption and bone health. Your skin produces it from sunlight, but many people fall short, especially in northern climates.
- Vitamin E: 15 mg. An antioxidant found in nuts, seeds, and vegetable oils.
- Vitamin K: 120 mcg. Essential for blood clotting and bone metabolism. Leafy greens are the richest source.
- Thiamin (B1): 1.2 mg
- Riboflavin (B2): 1.3 mg
- Niacin (B3): 16 mg
- Pantothenic acid (B5): 5 mg
- Vitamin B6: 1.7 mg
- Biotin (B7): 30 mcg
- Folate (B9): 400 mcg. Especially important during pregnancy to prevent neural tube defects.
- Vitamin B12: 2.4 mcg. Found almost exclusively in animal products, so people eating a plant-based diet often need a supplement.
The B vitamins collectively help convert food into energy, support your nervous system, and build red blood cells. Most people who eat a varied diet get enough of them without thinking about it, with B12 being the notable exception for vegetarians and vegans.
Essential Minerals
Minerals play structural and regulatory roles throughout your body. Five deserve special attention because they’re the ones people most commonly fall short on.
- Calcium: 1,000 mg per day for most adults. Women over 50 and men over 70 need 1,200 mg. Dairy products, fortified plant milks, tofu, and leafy greens are the main sources. Don’t exceed 2,500 mg.
- Iron: 18 mg per day for women aged 19 to 50, and 8 mg for men and for women over 50. The higher number for younger women reflects menstrual losses. Iron deficiency is the leading cause of anemia worldwide and can significantly limit physical energy and work capacity.
- Magnesium: 310 to 320 mg for women, 400 to 420 mg for men. Involved in hundreds of enzyme reactions, from muscle contraction to blood sugar regulation. Nuts, whole grains, and dark leafy greens are good sources.
- Potassium: 2,600 mg for women, 3,400 mg for men. Helps regulate blood pressure and fluid balance. Bananas get the credit, but potatoes, beans, and avocados actually contain more per serving.
- Zinc: 8 mg for women, 11 mg for men. Supports immune function and wound healing. The upper safe limit is 40 mg.
Omega-3 Fatty Acids
Your body cannot make omega-3 fats on its own, so you need to get them from food. The baseline recommendation is 1.6 grams of ALA (the plant form) per day for men and 1.1 grams for women. Flaxseeds, chia seeds, and walnuts are the richest plant sources.
EPA and DHA, the forms found in fatty fish, don’t have an official daily recommendation from U.S. health agencies. However, research suggests that around 2 to 3 grams of combined EPA and DHA per day may help lower blood pressure and triglycerides. Two servings of fatty fish per week (salmon, sardines, mackerel) is a practical way to get a meaningful amount.
How Nutrients Work Together
Nutrients don’t work in isolation, and what you eat alongside them matters. Fat-soluble vitamins (A, D, E, and K) need dietary fat to be absorbed properly. Eating a salad with olive oil or dressing, for example, helps your body take in far more vitamin A from the greens than eating them plain.
Vitamin C dramatically improves how well you absorb iron from plant-based foods. Squeezing lemon over lentils or eating an orange with a spinach salad makes a real difference. On the other hand, phytic acid, found in legumes, whole grains, and seeds, binds to calcium and iron and reduces how much your gut can absorb. Soaking, sprouting, or fermenting these foods breaks down some of the phytic acid.
Vitamin B12 depends on calcium and a protein your stomach produces called intrinsic factor. Without both, absorption drops sharply, which is one reason B12 deficiency becomes more common with age.
What Changes After 50
Three nutrients become harder to absorb as you get older: vitamin D, calcium, and B12. Your stomach produces less acid with age, which directly reduces B12 absorption. Your skin also becomes less efficient at producing vitamin D from sunlight, and your intestines become less responsive to vitamin D’s role in pulling calcium from food. This combination is why older adults are at higher risk for bone loss and why calcium and vitamin D recommendations increase after 50 and 70 respectively.
Many older adults also cut back on dairy due to real or perceived lactose intolerance, which further reduces calcium intake. Fortified foods or supplements can help fill the gap. For B12, the synthetic form found in supplements and fortified foods is actually easier to absorb than the form in meat, making it a practical option for older adults regardless of diet.
Signs You May Be Falling Short
Most mild deficiencies don’t produce obvious symptoms right away. But a few are worth knowing about. Persistent fatigue, weakness, and pale skin can signal iron deficiency anemia. Bone pain, frequent illness, and muscle weakness may point to low vitamin D, which over time can lead to softening of the bones. Tingling or numbness in the hands and feet, difficulty with balance, and brain fog are classic signs of B12 deficiency, which can cause lasting nerve damage if ignored for too long.
If you eat a reasonably varied diet that includes vegetables, fruits, whole grains, protein sources, and some healthy fats, you’re likely covering most of your bases. The nutrients people most commonly miss are vitamin D (especially in winter or at higher latitudes), iron (especially for menstruating women), calcium, potassium, and B12 (especially for plant-based eaters and adults over 50). Those are the ones worth paying closest attention to.