Mushrooms for dietary Vitamin D
Mushrooms, when grown under UV light or outdoors, are the only plant-based source of vitamin D? For people on a plant-based diet very few foods contain vitamin D. So, during winter, when there’s insufficient UVB radiation to produce vitamin D naturally, we run the risk of not having enough.
The mushroom’s ability to create vitamin D is legendary. It can do it after freshly harvested mushrooms are left in the sun, and for a relatively short period of time. In fact, as the mushroom’s respiration rate increases after harvest, this increases the speed at which mushrooms can create vitamin D.
Quick Facts
- Mushrooms make vitamin D in a similar way to our own bodies, through the absorption of sunlight (the UV spectrum) by the skin.
- Vitamin D is fat-soluble. This means you will need to eat it with some fats (like oils) in order for the body to absorb it. So, frying mushrooms is a benefit.
- Vitamin D is an important vitamin often lacking in plant-based diets.
- Vitamin D’s primary role is to help us absorb calcium and phosphorous from food, so extremely important for long-term bone health. Lack of Vit D will result in weak and brittle bones (including teeth).
- It is also a very essential vitamin for our immune system. Research shows that vitamin D deficiency is linked to increased autoimmune issues and a higher risk of developing infections. Here’s a link to Rhonda Patrick podcast on this https://www.foundmyfitness.com/episodes/vitamin-d-immune-function
- Mushrooms contain vitamin D-2, while animal products contain vitamin D-3. Research [Source[ has found that vitamin D-2 might not be as bioavailable as vitamin D-3 but can still raise overall vitamin D levels.
- Winter can be a problem for some people’s ability to manufacture vitamin D through lack of sunlight.
What happens if I don’t get enough?
Vitamin D deficiency can cause several health issues. You’re at a greater risk of developing a deficiency if you don’t get regular sun exposure and are lacking it through your diet. This can be a greater problem for people with darker skin, especially the further south, for people living in NZ. It can also be an issue for people who overdo the suncream. Some symptoms of low vitamin D include the following:
- weakened immune system
- weak bones
- depression
- fatigue
- slow wound healing
- hair loss
How much Vitamin D will I need?
Your age will determine how much vitamin D you need each day. The National Institutes of Health [Source], says that an average daily intake of 400 to 800 IU, or 10 to 20 micrograms, is sufficient for more than 97% of people.
Here’s the recommended daily intake of vitamin D based on age:
- Babies (0–12 months): 400 IU
- Children (1–13): 600 IU
- Teenagers: 600 IU
- Adults 70 and under: 600 IU
- Adults over 70: 800 IU
Can I overdo it?
Yes, this is possible. The upper safe limit of dietary vitamin D for people ages 9 and above is 4,000 IU [Source] per day. Taking too much can cause the following symptoms.
- loss of appetite
- nausea
- vomiting
- constipation
- weakness
- weight loss
- Getting too much vitamin D can also raise calcium levels in your blood. Excess calcium can cause an irregular heartbeat and disorientation.
Further reading