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10 min read
Vitamins can come from a variety of sources. Most people think of foods and supplements when considering what sources are available to them. But there is a natural source of vitamin D that should not be forgotten. The sun! Exposure to sunlight is an excellent source of vitamin D.
Now technically there aren’t vitamins in the sun, but exposure to sunlight can help our bodies produce vitamin D, a critical nutrient for bone and immune health. Sunlight is only one source of vitamin D and it should be balanced with other sources to ensure you are getting adequate vitamin D intake.
Vitamin D is a nutrient in your body that may come from many sources. Vitamin D is a fat-soluble vitamin that exists in one of two forms: D2 (ergocalciferol) and D3 (cholecalciferol). The benefits of Vitamin D are widely known. Vitamin D’s influence on bone growth and strength may be the most notable benefit. As mentioned above, there are various sources of vitamin D, including food, sunlight, and dietary supplements. For many people, it is most ideal to get vitamin D from a combination of these sources. Depending on where you reside, however, it may be challenging to get vitamin D from the sun. Many locations experience hundreds of days of cloud cover each year. Therefore, your food and supplement intake will be a very important consideration.
Vitamin D is best known for its role in building strong bones and supporting immune health. The benefits of vitamin D go beyond bone strength though. A few well known benefits of vitamin D include:
And a panel of experts concluded “that a cause and effect relationship has been established between the dietary intake of vitamin D and contribution to the normal function of the immune system and healthy inflammatory response, and maintenance of normal muscle function.”
There are three primary sources of vitamin D: (1) the sun, (2) food, and (3) supplements. Each of these sources has pros and cons. The sun is the perfect place to begin because it is free and often an easy way to increase your vitamin D levels.
Depending on your location, sunlight may be abundant. Even if you reside somewhere that gets less sunshine, you can still benefit from the sunny days that do occur. Our bodies are able to absorb the ultraviolet (UV) radiation emitted by the sun and convert a chemical precursor that is already present in our skin. This precursor is called 7-dehydrocholesterol (7-DHC). When we expose our skin to sunlight, UV radiation is absorbed and this precursor is converted to vitamin D3. The radiation from the sun serves as the energy necessary for this conversion to occur.
Vitamin D can also be obtained through food or dietary supplements. There are not many foods that naturally contain vitamin D, but foods such as salmon and egg yolks do contain this vitamin. Other foods are fortified with vitamin D. This simply means that the food company is adding vitamin D before selling or delivering the food product to the customer.
Since vitamin D does not occur naturally in many foods, and too much sunlight exposure presents the risk of future skin concerns (e.g. skin cancer), many adults rely on dietary supplements to meet their vitamin D needs. When selecting a vitamin D supplement, you should search for a high quality product with transparent labeling. There are two types of vitamin D: D2 (ergocalciferol) and D3 (cholecalciferol). If your doctor does not have a preference, you may want to begin with D3 because it is the naturally occurring form and it may raise your vitamin D level more effectively.
Many people rely on a combination of the three sources of vitamin D detailed above. Whether you are deficient in vitamin D or aiming to maintain your levels, your physician can also assist you in selecting the most ideal source.
There is no evidence that states the ideal amount of time for a person to be exposed to the sun. A person’s reaction to sunlight can differ based on skin tone, genetics, and many more factors. A daily recommendation of 30 minutes is often adequate for most adults. This length of time enables you to reap the benefits of sunlight exposure without putting yourself at great risk for future health conditions. There is some evidence that midday sunlight exposure is most ideal since the sun is at its highest point. Therefore, you can spend less time in the sun but enjoy greater benefits since the sun is “strongest” midday.
The short answer is yes, suncrease does lower the amount of vitamin D that your body produces from sunlight. It is important to note, however, that many people do not put on enough sunscreen to significantly block UV rays from hitting their skin. Therefore, the answer truly depends on the manner in which you apply sunscreen. Sunscreen does block UV rays from hitting the skin, which ultimately prevents the conversion of 7-DHC to vitamin D3. If it is your goal to produce vitamin D from sunlight exposure, you may need to keep the sunscreen off for up to 30 minutes.
Yes, you can overdose on vitamin D, but it is not common. Very large doses of this vitamin are required to trigger an overdose. The risk of an overdose, however, should still be taken seriously. Before adding a vitamin D supplement to your regimen, you may want to speak with your physician about the most appropriate dose. Your physician will likely recommend a blood test to determine your current vitamin D levels.
Vitamin D is one of the most common nutrient deficiencies. According to the US National Center for Health Statistics, an estimated 70% of US citizens may be considered vitamin D deficient. In addition, according to the Journal of Clinical Endocrinology and Metabolism, elderly populations are particularly at risk of vitamin D deficiency, in part because aging depletes our bodies’ natural ability to naturally produce and absorb vitamin D.
Vitamin D supplements are ideal for people that are looking to maintain or increase their current vitamin D level. If you are deficient in vitamin D, a supplement will likely be the quickest and most effective way to increase your vitamin D levels.
When selecting a vitamin D supplement, you should search for a high quality product with transparent labeling. There are two types of vitamin D: D2 (ergocalciferol) and D3 (cholecalciferol). If your doctor does not have a preference, you may want to begin with D3 because it is the naturally occurring form and it may raise your vitamin D level more effectively. If you have minor to moderate deficiency, a daily dose between 600–1,000 IU will likely work well to negate your deficiency.
Did you know that natural supplement forms of D3 come from two sources? Vegetarian D3 is most commonly derived from sheep lanolin and vegan D3 can be derived from algae. These options make it easy to find a high quality supplement that works well for you.