srch srch

Everything you need to know about Organic Vitamin D

Sunday October 27, 2019
Everything you need to know about Organic Vitamin D

When eating organically and ethically, consuming a therapeutic amount of vitamin D can be difficult. Vitamin D is a fat-soluble vitamin found in oily fish and egg yolks, however for vegans and vegetarians the only food source is mushrooms or a vegan vitamin D3 supplement.


The vitamin D content of mushrooms varies across species; for example, oyster mushrooms provide 24iu per 80 gram serving, whereas a paltry 3iu/80g of vitamin D is provided by Crimini mushrooms.  These figures improve with dehydration as vitamin D is a fat-soluble vitamin and is not affected by drying.  However, for an individual seeking to consume 400iu of vitamin D, that is a lot of mushrooms!

The conundrum can be made easier by considering the mushroom derived Organic Vitamin D food supplement.  

Here are some interesting facts about organic vitamin D:


1. Viridian Nutrition’s Organic Vitamin D is derived from Agaricus bisporus mushrooms, providing 400iu per capsule in accordance with Public Health England recommendation.


2. Agaricus bisporus are a member of the basidiomycete fungi family, traditionally found in the grasslands of Europe and North America.  When assessed for vitamin D content they have been found to far exceed other mushrooms providing up to 954iu per 100g.


3. Mushrooms are able to make vitamin D from UV sunlight exposure, subsequently Agaricus bisporus mushrooms exposed to UV rays will optimise the vitamin D content.  Studies have shown that UV exposed Agaricus bisporus can contain as high as 1320iu per 100g.  Plus, this figure increases once the mushrooms are dehydrated, therefore producing an organic vitamin D rich food.

4. Mushroom derived vitamin D is in the form of ergocalciferol also called vitamin D2.  Vitamin D2 is converted to the active 1,25-dihydroxyvitamin D2 in a 2 stage transformation process, firstly in the liver and secondly in the kidneys.  It is in this form that it then exerts its benefits to health. 


Subsequently vitamin D is extremely important. It contributes to the normal absorption and utilisation of calcium and phosphorus, that contributes to the maintenance of bones and teeth. Furthermore, it contributes to normal muscle and immune function. The role of vitamin D should not be underestimated!


Author: Jenny Carson is a Nutritional Practitioner and Technical Supervisor at Viridian Nutrition. She holds a BSc honours degree in Nutritional Science and is currently studying for MRES in Public Health.


Viridian Nutrition is the leading supplier of food supplements to specialist independent health food stores. For information about personalised solutions visit

Kristensen HL, Rosenqvist E, Jakobsen J. Increase of vitamin D2 by UV-B exposure during the growth phase of white button mushroom (Agaricus bisporus). Food & Nutrition Research. 2012;56:10.3402/fnr.v56i0.7114. doi:10.3402/fnr.v56i0.7114.
Pirjo H. Mattila, Vieno I. Piironen, Esko J. Uusi-Rauva, and Pekka E. Koivistoinen.  Vitamin D Contents in Edible Mushrooms.  Journal of Agricultural and Food Chemistry 1994 42 (11), 2449-2453.
Tripkovic L, Lambert H, Hart K, et al. Comparison of vitamin D2 and vitamin D3supplementation in raising serum 25-hydroxyvitamin D status: a systematic review and meta-analysis. The American Journal of Clinical Nutrition. 2012;95(6):1357-1364. doi:10.3945/ajcn.111.031070.


Related articles:

Everyone needs to supplement with Vitamin D - it's official

The information contained in this article is not intended to treat, diagnose or replace the advice of a health practitioner. Please consult a qualified health practitioner if you have a pre-existing health condition or are currently taking medication. Food supplements should not be used as a substitute for a varied and balanced diet.


TAGS: Nutrition News and Viewsvitamin D


Back To Top

The Leading Brand of ethical vitamins