How to Make Sure You Get Enough Vitamin D in Fall

The National Institutes of Health says about one in four Americans are low in vitamin D. This vital nutrient becomes even more important as the weather turns cooler in fall and winter.

Vitamin D is often called the sunshine vitamin because the body produces it when exposed to sunlight. As people spend more time indoors, health experts recommend paying attention to vitamin D levels, especially because of its connection to immune health.

Vitamin D plays an important role in supporting the immune system, which matters even more during cold and flu season. It also helps keep bones, teeth, and muscles healthy, and it supports the brain, nervous system, insulin regulation, cardiovascular health, and lung function.

The main sources of vitamin D are food, sunlight, and supplements. Dietary sources include oily fish, eggs, meat, dairy products, and fortified foods such as breakfast cereal.

Older adults, people who rarely go outside, and people with darker skin may have a harder time getting enough sunlight to maintain healthy vitamin D levels.

If needed, ask a doctor to check your levels and discuss supplements. The recommended daily amount of vitamin D depends on age, sex, and health status. In general, adults need 600 to 800 IU per day, though people with a deficiency may need more.

Regular exercise can also support overall health and well-being. A common goal is at least 30 minutes of moderate activity on most days.

Possible signs of vitamin D deficiency include muscle weakness, fatigue, mood changes, frequent infections, hair loss, bone pain, and slow wound healing.

Sunlight is a natural way the body makes vitamin D, but that can be tricky because many people use sunscreen when they go outside, as they should. Experts say around 10 minutes of midday sun with about 25% of the body exposed, such as the arms and legs, may be enough, though winter usually requires a bit more time. Many dermatologists favor supplements because they do not want people to expose unprotected skin to strong midday sun.