Vitamin D has two variants, D2 and D3. Vitamin D2 is also known as ergocalciferol. Vitamin D3 is also known as cholecalciferol. Although both are the same type of vitamins and can cater to similar needs of the human body, there is substantial difference between vitamin D2 and D3.
The primary difference between vitamin D2 and D3 is that the first is a found in plants while the second is found in animals. Vitamin D2 is found in milk, cereals and many other plants. It can also be found on certain types of fungi. Vitamin D3 is actually synthesized in the human body. Other animals can also produce vitamin D3.
Since vitamin D3 can be synthesised by the human body, it is also regarded as a hormone. Among animal sources, vitamin D3 can be found in fish liver and fish oils which are the most commonly opted for alternatives. Vitamin D3 is synthesised in the human body when one is exposed to sunlight. In particular, UVB rays of the sun can lead to the synthesis of vitamin D3. Period exposure to the sun for about fifteen odd minutes, for about three to four days a week, would be sufficient to synthesise the desired quantum of vitamin D3 in the human body. In the absence of this, one has to opt for vitamin D3 supplements. It must be noted that the exposure to sun must be whilst not having in sunscreen on as that can prevent the skin from getting contact with UVB rays of the sun.
Vitamin D2 cannot be produced in the human body or in animals. Thus, one has to opt for plants and milk products or some cereals for the same. Vitamin D2 is also available in various forms of supplements, similar to D3, which can be opted for during vitamin deficiency.
Both vitamin D2 and D3 cater to the purpose. They help in the absorption of calcium in the human body. These two vitamins help bones to absorb calcium from the blood and they also maintain a healthy level of calcium circulation through the blood to prevent any bone damage. To this effect, these two vitamins are quintessential to prevent or to cure conditions like osteopenia, osteomalacia and osteoporosis.
Vitamin D2 can be obtained directly from the sources in food form or in supplement form. Vitamin D3 can be naturally produced by the body, in the absence of which one has to opt for supplements or specific diets.
A notable difference between vitamin D2 and D3 is that the latter is regarded as the more potent form of the vitamin to tackle problems of the bones.
