Recommended daily limit of vitamins and minerals
The vitamins and minerals daily dosage is the maximum amount of daily nutrition that you can safely take without risk of an overdose.
| Vitamin and Minerals (Common Names) | Recommended Dietary Allowance (RDA) or Daily Adequate Intake (AI)* | Recommended Daily Dosage Upper Limit | |
| Women | Men | ||
| Vitamin A (preformed = retinol; beta-carotene can be converted to Vitamin A) | 700 micrograms (2,333 IU) | 900 micrograms (3,000 IU) | 3,000 micrograms (about 10,000 IU) |
| Thiamin (vitamin B1) | 1.1 milligrams | 1.2 milligrams | Not known |
| Riboflavin (vitamin B2) | 1.1 milligrams | 1.3 milligrams | Not known |
| Niacin (vitamin B3; nicotinic acid) | 14 milligrams | 16 milligrams | 35 milligrams |
| Pantothenic Acid (vitamin B5) | 5 milligrams* | 5 milligrams* | Not known |
| Vitamin B6 (pyridoxal, pyridoxine, pyridoxamine) | Ages 19-50: 1.3 milligrams Ages 51+: 1.5 milligrams | Ages 19-50: 1.3 milligrams Ages 51+: 1.7 milligrams | 100 milligrams |
| Biotin (vitamin B7) | 30 micrograms* | 30 micrograms* | Not known |
| Folate (Folic acid; vitamin B9) | 400 micrograms | 400 micrograms | 1,000 micrograms |
| Vitamin B12 | 2.4 micrograms | 2.4 micrograms | Not known |
| Vitamin C | 75 milligrams* (Smokers add 35 milligrams) | 90 milligrams* (Smokers add 35 milligrams) | 2,000 milligrams |
| Choline | 425 milligrams* | 550 milligrams* | 3,500 milligrams |
| Vitamin D (calciferol) | Ages 19-50: 15 micrograms (600 IU) Ages 51-70: 15 micrograms (600 IU) Ages 71+: 20 micrograms (800 IU) | Ages 19-50: 15 micrograms (600 IU) Ages 51-70: 15 micrograms (600 IU) Ages 71+: 20 micrograms (800 IU) | 100 micrograms (4,000 IU) |
| Vitamin E (alpha-tocopherol) | 15 milligrams | 15 milligrams | 1,000 milligrams |
| Vitamin K (phylloquinone, menadione) | 90 micrograms* | 120 micrograms* | |
| Calcium | Ages 31-50: 1,000 milligrams Ages 51+: 1,200 milligrams | Ages 31-50: 1,000 milligrams Ages 51+: 1,200 milligrams | 2,500 milligrams |
| Chloride | Ages 19-50: 2.3 grams* Ages 51-70: 2.0 grams* Ages 71+: 1.8 grams* | Ages 19-50: 2.3 grams* Ages 51-70: 2.0 grams* Ages 71+: 1.8 grams* | Not known |
| Chromium | Ages 31-50: 25 micrograms* Ages 51+: 20 micrograms* | Ages 31-50: 35 micrograms* Ages 51+: 30 micrograms* | Not known |
| Copper | 900 micrograms | 900 micrograms | 10,000 micrograms |
| Fluoride | 3 milligrams | 4 milligrams | 10 milligrams |
| Iodine | 150 micrograms | 150 micrograms | 1,100 micrograms |
| Iron | Ages 31-50: 18 milligrams Ages 51+: 8 milligrams | Ages 31-50: 8 milligrams Ages 51+: 8 milligrams | 45 milligrams |
| Magnesium | Ages 19-30: 310 milligrams Ages 31-70+: 320 milligrams | Ages 19-30: 400 milligrams Ages 31-70+: 420 milligrams | 350 milligrams (from supplements) |
| Manganese | 1.8 milligrams* | 2.3 milligrams* | 11 milligrams |
| Molybdenum | 45 micrograms | 45 micrograms | 2,000 micrograms |
| Nickel | N/A** | N/A** | N/A** |
| Phosphorus | 700 milligrams | 700 milligrams | Ages 31-70: 4,000 milligrams Ages 71+: 3,000 milligrams |
| Potassium | Ages 14-18: 2,300 milligrams* Ages 19+: 2,600 milligrams* | Ages 14-18: 3,000 milligrams* Ages 19+: 3,400 milligrams* | Not known |
| Selenium | 55 micrograms | 55 micrograms | 400 micrograms |
| Sodium | 1,500 milligrams* | 1,500 milligrams* | Not determined; however a chronic disease risk reduction intake has been established |
| Zinc | 8 milligrams | 11 milligrams | 40 milligrams |
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Research suggests that the vitamins you obtain from the food you consume are generally more beneficial than those found in vitamin supplements. Although the synthetic vitamins in supplements are chemically identical to the naturally occurring ones, they do not seem to be as effective.
The primary exception to this is folate. The synthetic form of folate, whether in a supplement or fortified food, is better absorbed by the body compared to folate from natural food sources.
Food is a complex source of vitamins, minerals, and phytochemicals (plant-based compounds), all of which work together synergistically. Supplements, on the other hand, tend to work in isolation. Studies have shown that a food component that influences the body may not have the same effect when taken as a separate supplement. This could be because the vitamins and minerals in foods are also affected by other food components, not just the “active ingredient” alone.
Phytochemicals are an important part of food and are believed to reduce the risk of heart disease and certain cancers. Supplements do not provide the benefits of phytochemicals and other components found in food. Taking vitamin and mineral supplements cannot substitute for a healthy, balanced diet.