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:
References
5 Days
I am merely judging the delivery system, which was flawless. It wouldn't make any sense to comment on the efficacy of the supplements, since that is only possible on a statistical basis. Even if something doesn't improve, that doesn't have to mean that the supplement doesn't work, since one doesn't know how it might have worsened without the supplement and the opposite might also apply, since many symptoms are psychosomatic and the supplement might provide a placebo effect.
Roger De Backer
13 Days
Perfect!!!!!!!!!!!!!
Patrick
15 Days
Magnesium and Zinc Orotate are top supplements. Highly recommend!
Kristjan
26 Days
Nothing to complain. Delivers everything fast, attentive to their regular customers. Best experience.
FABIO I.
29 Days
Possibility to enjoy a variety of high quality suppléments. Fast delivery Good packaging Clear information and website
Vov Oo
31 Days
Efficient ordering and delivery. Happy with products. I order fairly regularly. Reliable
Gill Lee
31 Days
Supersmart sell the best products and are effecient when it come to handling and dispatching orders. Also, their return and refund policies is very simple and easy for the customer. The creme on top is the return customer discounts. Keep up the good work.
ABDULQADER Jehad
35 Days
Prompt and reliable.
MIFSUD Joseph
41 Days
I don't use the word great; everything was OK; it is maybe too early to expect an effect of the supplements
STAEHLI C
48 Days
Well,It was yesterday I started using it but I can tell the supplement is working perfect,will definitely still give best comments once I'm done using it ...
ANTHONY Oluwaseun Ugwu
49 Days
Great products, fast delivery.
Nujood ALHADDAD
58 Days
Easy and quick
Derya Iren
58 Days
Quick delivery, big choice of supplements. Good quality.
Val
61 Days
Great vitamins at a great price! I buy Bacillus subtilis which I really can’t find anywhere else which is great for intestinal health. 5 stars to Supersmart Vitamins.
Loli Vaughan
63 Days
Easy way to order. Fast delivery. Transporter FedEx was very polite and called me 1 hour before delivery.
TAJC Katja