Vitamins and minerals: How to get the nutrients your body needs

Vitamins and minerals are often discussed as essential for health, but knowing how they function matters just as much as making sure you get enough. These micronutrients play a role in nearly every process in the body, including energy production, immune protection, bone health, nerve signaling and cell repair. Unlike carbohydrates, protein and fat, they do not supply calories. Instead, they help the body use energy and carry out the work needed to stay healthy.

Most vitamins must be obtained through food. The body can make vitamin D when skin is exposed to sunlight, produce some niacin from the amino acid tryptophan and create vitamin K with the help of intestinal bacteria, though that bacterial production may not fully meet your needs. Minerals such as calcium, magnesium, iron and zinc must come from outside sources.

The National Institutes of Health says a varied, nutrient-rich diet is generally the best way to get essential vitamins and minerals.

Even so, eating a nutrient does not guarantee the body will absorb or use it well.

Fat-soluble vitamins A, D, E and K are absorbed more effectively when eaten with fat. Water-soluble vitamins, including vitamin C and the B vitamins, usually do not need fat for absorption.

Some nutrients work together, while others can interfere with one another. Vitamin C, for instance, helps the body absorb iron from plant-based foods. Strawberries with iron-fortified cereal or bell peppers with beans can improve iron absorption. On the other hand, large calcium supplements can reduce iron absorption if taken at the same time, and too much zinc may interfere with copper absorption.

When supplements are involved, timing can also make a difference. Some are easier to tolerate with meals, while certain iron supplements are absorbed better on an empty stomach. Taking iron with food, however, may help prevent stomach upset.

Multivitamins may help fill nutrition gaps, but they are not necessarily needed by everyone, so a more personalized approach can be useful. Instead of taking several supplements without knowing what your body needs, talk with a health care provider about your eating habits, medications, medical history and possible nutrient deficiencies. Blood tests may be appropriate when a deficiency is suspected, but routine testing for every nutrient is not needed.

Tips for improving nutrient intake:

- Eat a wide range of colorful fruits, vegetables, whole grains, proteins and healthy fats.

- Combine plant-based sources of iron with vitamin C to boost absorption.

- Add healthy fat to foods that contain vitamins A, D, E and K.

- Avoid assuming that more is better, since too much supplementation can be harmful.

- Check supplement timing with a pharmacist, especially if you take medication.

- Ask about testing if symptoms, food restrictions or health conditions point to a possible deficiency.

- Put food first and use supplements only when they are medically appropriate.

The aim is not to take the most vitamins or supplements possible. It is to give the body the nutrients it needs in forms and amounts it can actually use.