The Health Benefits of Vitamin D
Vitamin D plays an essential role in calcium absorption, bone strength, parathyroid gland function, and overall health. You can maintain appropriate levels of vitamin D by getting more sun exposure, taking supplements, and eating certain types of food.
Vitamin D Deficiency Symptoms
When vitamin D levels are low, you may suffer from adverse conditions, such as bone loss, joint pain, muscle cramps, tiredness, and changes in mood. What’s more, having prolonged vitamin D deficiencies can lead to chronic illnesses like osteoporosis, heart disease, diabetes, immune disorders, multiple sclerosis, and some forms of cancer.
How much vitamin D is enough?
For the majority of adults, the Institute of Medicine (IOM) recommends 400 to 800 IU of vitamin D per day. Further studies by the IOM suggest that the maximum daily intake ranges from 2,000 to 4,000 IU/day for most ages.
Vitamin D from the Sun
Most vitamin D can be obtained by getting some mid-day sun exposure throughout the week. Depending on your skin tone, aim for getting 10 to 30 minutes per day.
If you have paler skin, 10 minutes should be sufficient to absorb enough vitamin D. However, if you have darker pigmentation, you may want to stay out for longer for extra exposure.
Again, always avoid sunburns and know your skin’s limitations. Sometimes only a few minutes of direct sunshine is all you need to get enough vitamin D, especially if you have very pale skin.
Vitamin D from Supplements
If you cannot rely completely on the sun for your daily dose of vitamin D, you should consider supplementation. As recommended by the IOM, take a daily vitamin D3 ranging from 400 to 800 IU. Again, the maximum dosage should not exceed 4,000 IU.
Vitamin D from Food
Another natural way of boosting your vitamin D levels is to eat foods that contain larger amounts of vitamin D. View the chart below for a comprehensive list of foods that are rich in vitamin D.
Top 10 Foods with Vitamin D
|Food||Vitamin D (per 100g)||% Daily Value*|
Cod Liver Oil
Cremini Mushrooms (exposed to sunlight)
Portobello Mushrooms (exposed to sunlight)
White Button Mushrooms (exposed to sunlight)
Canned Sockey Salmon
Cooked Rainbow Trout
Cooked Sockeye Salmon
As you can see from the list above, mushrooms and fish have the highest amount of vitamin D. Since you may prefer not to have cod liver oil every day, you should consider adding mushrooms to your weekly diet. Furthermore, mushrooms contain nutritious amounts of B-vitamins, vitamin C, and potassium as well.
How to Increase Vitamin D Levels in Mushrooms with Sunlight
Although mushrooms contain some vitamin D when you buy them at the supermarket, 100 grams of mushrooms will typically contain only 100 IU of vitamin D. To boost the vitamin D levels of mushrooms, you must expose them to sunlight.
An experiment done in Washington state showed that exposing shiitake mushrooms to sunlight for 6 hours over a period of 2 days increased vitamin D levels to approximately 46,000 IU per 100 grams. That is nearly 460% higher than regular store-bought mushrooms.
Below is a brief summary of how to prepare and expose your mushrooms to the sun.
Guidelines for Exposing Mushrooms to the Sun
- Outside, use a tray or cooking sheet to align the mushrooms on.
- Remove the stems of the mushrooms to expose more surface area.
- Place the mushrooms on their heads to reveal the bottom sides to the sun.
- The stems can be used and exposed as well.
- Expose the mushrooms to sunlight for about 6 hours.
- In the evening, take the trays inside.
- The next day, repeat the steps.
After following this process, your vitamin-D enriched mushrooms can be used in soups, salads, and other dishes. Just remember to wash them before eating them.
How many mushrooms should you eat?
A German study showed that eating a handful of mushrooms 4 days per week was appropriate for maintaining a healthy balance of vitamin D in the blood.
Though, avoid consuming excessive amounts of mushrooms. Just like over-supplementation, it is important not to overeat. Therefore, remember to eat your sun-dried mushrooms within moderation.
Summary and Key Takeaways
Maintaining proper vitamin D levels in the body is essential for overall health, disease prevention, and longevity. The most natural source of vitamin D is through direct sun exposure.
However, you can also elevate your vitamin D levels through supplementation and by adding more fish and mushrooms to your diet. Specifically, eating mushrooms that have been exposed to sunlight provides an excellent natural source of vitamin D.
For more nutritional advice and articles about vitamin D, visit Health Benefits 101.
Please leave a comment at the bottom of the page after completing the poll.
VIDEO: More on Mushrooms & How to Increase Vitamin D Levels
Arnarson, A. (2018). Vitamin D2 vs. D3: What’s the Difference? [online] Available at: https://www.healthline.com/nutrition/vitamin-d2-vs-d3.
Cleveland Clinic (2019). Vitamin D Deficiency. [online] Available at: https://my.clevelandclinic.org/health/articles/15050-vitamin-d--vitamin-d-deficiency.
Foodstruct (2020). Edible mushroom nutrition, glycemic index, acidty and serving size. [online] Available at: https://foodstruct.com/food/edible-mushroom.
Harvard Health Publishing (2019). How much vitamin D do you need? [online] Available at: https://www.health.harvard.edu/staying-healthy/how-much-vitamin-d-do-you-need.
Harvard Health Publishing (2019). Vitamin D and your health: Breaking old rules, raising new hopes. [online] Available at: https://www.health.harvard.edu/staying-healthy/vitamin-d-and-your-health-breaking-old-rules-raising-new-hopes.
My Food Data (2020). 200 Foods Highest in Vitamin D (IU). [online] Available at: https://tools.myfooddata.com/nutrient-ranking-tool.php?nutrient=Vitamin-D-IU&foodgroup=All&sortby=Highest&servsize=100g&list=Simple&spices=No.
Passeri, G., Vescovini, R., Sansoni, P., Galli, C., Franceschi, C., Passeri, M., & Italian Multicentric Study on Centenarians (IMUSCE) (2008). Calcium metabolism and vitamin D in the extreme longevity. Experimental gerontology, 43(2), 79–87.
Stamets, P. (2012). Place Mushrooms in Sunlight to Get Your Vitamin D. [online] Available at: https://fungi.com/blogs/articles/place-mushrooms-in-sunlight-to-get-your-vitamin-d.