Vitamin D sometimes referred to as the “sunshine vitamin,” functions to fight against autoimmune diseases, depression, heart disease, and the flu. As important as this essential nutrient is, it has been estimated that over 50% of our world population is deficient in vitamin D.

This deficiency has even become a worldwide health issue because it is an individual risk factor for mortality rates across the globe. That being said, it is necessary to understand how vitamin D functions in the body, how much we need, and how we can get it.


1. Vitamin D’s Role in the Bodysunlight

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Vitamin D is necessary for the proper functioning of many bodily systems, but its main role is in growing strong bones. This is achieved by aiding in calcium absorption, a mineral that supports structure and hardness in the bones. If you are deficient in Vitamin D, it could lead to brittle bones later on in life resulting in osteomalacia.

Besides supporting the overall structure of the body, vitamin D also supports:

  1. Muscle Movement, which is stimulated by calcium metabolism produced by vitamin D. When your muscles contract, this is due to nerve stimulation brought on by calcium flow between muscle compartments. In order for this response to occur, normal levels of calcium must remain consistent. If you are experiencing muscle twitching, it could be a sign that you are low in vitamin D.
  2. The Immune System by defending the body from viruses and bacteria. It does this by casting signals within mobile white blood cells, or macrophages, enabling them to kill bacterial organisms.
  3. A Healthy Heart by protecting the cardiovascular system from osteoporosis. A study was conducted that found vitamin D to be excellent at triggering the release of nitric oxide, a molecule that controls blood flow and clot formation in blood vessels. It was also found that vitamin D lowered oxidative stress in the heart, lowering the risk of heart disease and heart attacks.

2. How Much Vitamin D Do We Need? 



Because vitamin D deficiency can lead to a plethora of health-related problems, researchers have been working hard to determine the recommended intake for optimal health. Controversies over the subject have also arisen concerning how much vitamin D is necessary to prevent these deficiencies.

The Institute of Medicine recommends that we get anywhere from 400-800 IU’s of Vitamin D on a daily basis, dependent upon your age. On the other hand, the Vitamin D Council believes that 5,000 IU’s a day should be the proper dosage. So with all of this mixed information, how do we determine our dosage of vitamin D and how our body individually absorbs this nutrient? Well, there are a few contributing factors that could alter your recommended daily value.


As you age, the levels of the substance in your skin that convert UVB light to vitamin D may lessen. This means that vitamin D production is less efficient, and you may need to up your dosage.

Latitude of where you live/Sun Exposure

When you live in a location at a higher latitude level, the angle of the sun lowers during the winter and affects vitamin D producing UVB light. This is why it is recommended to supplement this time of year, especially when you live in an area with limited sun exposure.


Melanin levels

Higher melanin levels reduce the skin’s production of vitamin D from the sun. The more melanin present in your skin, the longer it takes for vitamin D synthesis from the sun.

Gut Health

Vitamin D sourced from supplementation or food is absorbed in the small intestine. Factors like pancreatic secretions and the integrity of intestinal stomach lining will affect how much of this vitamin is absorbed. That is why conditions like Crohn’s or celiac disease, which influence the gut, could hinder the rate of vitamin D absorption.


Depending on the above conditions, you may need to alter your daily exposure or intake of the sunshine vitamin. For those limited from sun exposure, MD Thomas Campbell, coauthor of The China Study, recommends 600-800 IU’s a day. He also notes that getting your daily dose of vitamin D is extremely easy to do during warmer months. Even on a cloudy day, your body will still synthesize this vitamin.

3. Sources of Vitamin D mushrooms

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Vitamin D is not easily obtainable from food sources. The only options for vegan dietary intake of this vitamin are from mushrooms or from foods fortified with vitamin D, such as vegan fortified cereals, or plant-based milk or yogurts. Consuming a diet of mushrooms and fortified plant milk, however, will still not meet your vitamin D needs.

This is why it is crucial to obtain this nutrient from the sun. When directly exposed to the midday sun for 5-30 minutes twice a week (depending on the variables above), you will easily obtain sufficient vitamin D levels. Because this vitamin is fat-soluble, it will also remain stored in your liver and fatty tissue over a period of time to be released when your body needs it most.


Supplementation is also an option and is even recommended during the winter when getting outside isn’t possible. Some vegan vitamin D supplements are made by brands like Deva Vegan Vitamins, Garden of Life, and MRM.

If you are still unsure as to how much vitamin D your individual body needs, be sure to consult your doctor.

If you are looking for more information like Vitamin D Decoded + Vegan Supplement Optionswe recommend downloading this Food Monster App, which is available for both Android and iPhone and can also be found on Instagram and Facebook. The app has more than 10,000 plant-based, allergy-friendly recipes, and subscribers gain access to new recipes every day. Check it out!

Lead Image Source: Hernán Piñera/Flickr