Vitamin D - What is it and How Can You Ensure You Get Enough On a PBD?


What is Vitamin D

Interestingly, vitamin D is actually a hormone. It is required primarily to aid the absorption of calcium from the gut into the bloodstream and is mostly produced in the skin as a response to sunlight and a small amount is absorbed from food eaten. The kidneys and liver convert vitamin D into the active hormone called calcitriol. Calcitriol can then help increase the quantity of calcium the gut can uptake from food and prevent calcium loss in the kidneys. It also impacts bone cells and aids the formation of new bone.

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Why do we need vitamin D?

Calcium and phosphorus are essential for building bones vitamin D is required in order to absorb these minerals. Even if you eat food that contain a high volume of calcium and phosphorus your body can’t absorb them adequately without vitamin D.

Without sufficient vitamin D, bones can become thin, brittle, or misshapen. Vitamin D sufficiency prevents rickets in children and osteomalacia in adults. Together with calcium, vitamin D also helps protect older adults from osteoporosis. It’s also an important factor in making sure your muscles, heart, lungs and brain work well and that your body can fight infection and influences many other bodily processes, including mood, memory and muscle recovery.

Where can you get it from?

Vitamin D is known as “the sunshine vitamin” because our bodies make vitamin D from exposure to the sun. According to the NIH, 5 – 30 minutes of sun exposure between 10 am and 3 pm twice a week to the face, arms, legs, or back without sunscreen is usually enough to help boost vitamin D intake. This varies largely depending on the season, time of day, cloud cover, skin color, and sunscreen use, so in order to ensure you’re getting enough it can be helpful to supplement with food sources of vitamin D (such as fortified dairy products, or some mushrooms).

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Although Vitamin D can be attained through sunlight exposure, fortified foods and naturally occuring foods, vitamin D deficiency is reported worldwide in vegans and omnivores alike. The best way you can ensure you’re getting enough vitamin D is to have your blood levels tested. Those unable to get enough from fortified foods and sunshine should consider taking a daily vitamin D2 or vegan vitamin D3 supplement.

How much do we need?

The RDA for vitamin D for children and adults is 600 IU (15 mcg) per day. The elderly, as well as pregnant or lactating women, should aim for 800 IU (20 mcg) per day (22).

In practical terms, if you were hoping to get it from a natural food source you’d have to eat a lot of mushrooms to meet your quota. One cup of mushrooms contains only 7IU. However, you can simply increase the amount of vitamin D in your mushrooms by placing them in the sun. Just 15 minutes of direct sun­light can produce 200 to 800 IU in 3 ounces of mushrooms, regardless of type or season. If you do this your­self, place the mushrooms with the “gills” facing the sun to increase D production.

Or you could choose to simply take a supplement.