The sun is one of the best sources of vitamin D for the human body. How much sun a person needs per day depends on factors such as skin type, the season, and cloud coverage.
Vitamin D is an essential nutrient for the body. The body needs vitamin D to absorb calcium. Vitamin D also plays a role in bone growth, bone healing, and immune system function.
People can get vitamin D from sunlight exposure. However, it is important to use suitable protection, such as sunscreen. People can also get vitamin D from certain foods and supplements.
This article looks at how the body gets its vitamin D from the sun, tips for maximizing vitamin D production, and other ways to get vitamin D.
When the sun’s rays hit the skin,
Many factors affect how much vitamin D a person gets from the sun. Some of these
- Time of day. The skin produces more vitamin D when in the sun during the middle of the day, the time it is at its highest point in the sky. When spending prolonged time in the hot sun, wear sunscreen, and stay hydrated.
- Amount of skin exposed. The more skin a person exposes, the more vitamin D the body will make. Exposing the back, for instance, allows the body to produce more vitamin D than just the hands and face.
- Skin color. Pale color skin makes vitamin D more quickly than darker colored skins.
In the United States, people in the sunnier southern states will find it easier to meet their vitamin D needs with sun exposure than those in the northern states. This is especially true in the winter months when the sun is lower in the sky.
Evidence suggests that during the lighter months, people with lighter skin types require roughly 10 to 15 minutes of daily sunlight exposure. For those with darker skin types, it is advisable to get 25 to 40 minutes. In winter months, people will typically require more sun exposure.
Frequent, moderate exposure to the sun is healthful, but prolonged exposure can be dangerous.
It is important to note that when someone stays in the sun so long that their skin burns, they have a higher risk of developing skin cancer.
The sun is the best natural source of vitamin D. Spending even a short time in the sun can provide the body with all of the vitamin D it needs for the day. A person just simply needs to expose their skin to sunlight for it to make vitamin D. However, it is important to get a suitable amount of exposure and avoid burning the skin.
Depending on the season, people with fairer skin may require 10 to 30 minutes a day, while darker skin types may require 20 to 90 minutes.
The body needs a steady source of vitamin D for many different processes. For example, vitamin D helps the body to absorb calcium, which is one of the main building blocks of bone. The body also needs vitamin D to keep the nerves, muscles, and immune system working properly.
Read on to learn more about vitamin D and calcium.
Wearing sunscreen can prevent sunburn by blocking ultraviolet (UV) light. As such, this means using sunscreen may slightly limit the body’s ability to make vitamin D. However, it is unlikely to have much of an impact and the risk of sunburn outweighs a slight reduction in vitamin D.
Some types of glass can also block UV rays and may prevent the skin from producing vitamin D. However, glass may not be able to block all UV rays and a person can still experience sunburn from sunlight through glass.
Some people’s skin is less able to make vitamin D than others. Others may not be able to adequately release vitamin D into their blood circulation from fat cells. Also, certain individuals may not activate vitamin D to a usable state. These people may find themselves at risk of vitamin D deficiency, including:
- older people
- people with darker skin
- people who are obese
- people with kidney or liver disease
- people living with conditions that make it difficult to absorb nutrients from food, such as Crohn’s disease, ulcerative colitis, and celiac disease
- those taking medication that can impact vitamin D levels, such as cholesterol, antiseizure, steroid, and weight loss drugs
Vitamin D sources include the sun, certain foods, and vitamin D supplements.
In the United States, the
- Children and teenagers: 600 international units (IU) or 15 micrograms (mcg).
- Adults up to the age of 70 years old: 600 IU or 15 mcg.
- Adults aged 71 years old and over: 800 IU or 20 mcg.
- During pregnancy and breastfeeding: 600 IU or 15 mcg.
Some foods are higher in vitamin D than others. Eggs, sardines, and salmon naturally contain vitamin D. Also, manufacturers fortify most milk and some brands of yogurt and breakfast cereals with the vitamin.
Examples of foods that contain vitamin D include:
- sockeye salmon
- canned tuna
- canned sardines
- 1% fortified milk
- low fat vanilla yogurt
- fortified orange juice
- fortified breakfast cereal
- hard boiled eggs
Vitamin D rich food and supplements are particularly important for people who find it difficult to get the vitamin from exposure to the sun, and those who cannot spend much time outside.
Older people, those with darker skin, other groups whose skin is less able to make vitamin D, and individuals at higher risk for vitamin D deficiency may wish to consider taking a supplement.
It is worth noting that, while it is rare, vitamin D toxicity can occur and cause nausea, constipation, weakness, and kidney damage.
Sun exposure is the most important natural source of vitamin D. The body uses the vitamin to absorb the calcium it needs to build and maintain bones.
Short bursts of sun exposure can usually allow your body to produce all the vitamin D it needs for the day. Some people, including older people or those with kidney or liver problems, may be at risk of becoming deficient in vitamin D. They can consider eating more foods that contain vitamin D or taking a supplement.
When exposing the skin to the sun, it is essential to consider the risk of skin cancer. People should avoid allowing their skin to burn.