There are two forms of vitamin D in the body – D2 and D3: their empirical chemical formulae differ by a single carbon atom. We get them from different sources: D2 is found primarily in plant-based foods, while D3 is obtained from animal-origin foods, and is also produced when our skin is exposed to the sun’s rays.
Vitamin D3, or cholecalciferol, is synthesised from a sterol (complex lipid) called 7-dehydrocholesterol, naturally present in the body. When this sterol is exposed to the sun’s UVB rays, it is converted into vitamin D. Most of the vitamin D circulating in the body is produced in this way (1). That’s why we’re advised to expose our skin as much as possible to natural light. Vitamin D3 is also obtained from the diet, in particular from oily fish and egg yolk.
Vitamin D2, or ergocalciferol, is a derivative of ergosterol, a sterol naturally present in the cell membranes of certain plants and fungi. Vitamin D2 is obtained by exposing ergosterol to the sun’s UVB rays. It is found in mushrooms (especially those exposed to UVB rays) as well as in vitamin D-fortified foods like margarine.
Vitamins D2 and D3 are both metabolised in the liver into calcifediol and then converted in the kidneys into calcitriol, the active and usable form of vitamin D (2). However, research has shown that vitamin D3 increases the level of calcitriol in the body to a greater degree (3). It is also less sensitive to heat and humidity than D2 and thus more stable (4).
As a consequence, if you wish to take a vitamin D supplement, vitamin D3 is the better choice. You have three options to choose from:
Would you like to know how supplements are produced? Supersmart shares with you the different stages of production of a dietary supplement.
A true concentrate from Nature, shilajit is an extraordinary substance, long-prized by practitioners of Ayurvedic medicine. What are the benefits (and contraindications) of the famous ‘mountain tears’?
When it comes to the trace-element magnesium and vitamin B6, there’s strength in unity. Discover why you should combine the two.
It’s a question many of us ask but to which there’s no clear-cut answer, as supplements usually meet specific needs. Read on for our view on the subject.
Let’s get rid of any misconceptions with a list of foods and dietary supplements that either do or don’t need to be refrigerated.
Marvels of nature, adaptogenic plants help to strengthen the body by relieving stress. Discover the 8 best adaptogenic plants as listed by the European Food Safety Agency (EFSA).
The most complete multivitamin supplement you can take in a single capsule
$49.00Beneficial for cardiovascular health. 90% delta-tocotrienols, the most biologically active form of vitamin E.
$34.00
The wish list lets you save items you're interested in so you can add them to your cart easily the next time you visit the site.
You need to be registered to use this service.
