Vitamin D plays a crucial role in helping people with MS maintain their health - when choosing a supplement, vitamin D3 (cholecalciferol) is the preferred option.
Vitamin D comes in two main forms: vitamin D2 (ergocalciferol) and vitamin D3 (cholecalciferol). Both help the body maintain healthy bones and support the immune system, but they come from different sources and work slightly differently in the body.
Vitamin D3 is more bioavailable than vitamin D2, meaning it is absorbed and used more efficiently by the body. Bioavailability refers to how much of a substance actually gets into your bloodstream and is available for your body to use. A nutrient with higher bioavailability is absorbed more effectively and stays in the body longer, making it more beneficial.
A recent study compared how well vitamin D2 and vitamin D3 increase vitamin D levels in the blood. While both forms are available as supplements, vitamin D3 was found to be 40% more effective than D2 at raising overall vitamin D levels.
This is because:
It remains in circulation for a longer time, helping to maintain stable vitamin D levels.
The body converts both D2 and D3 into 25-hydroxyvitamin D (25(OH)D), the form measured in blood tests. However, vitamin D3 is converted more efficiently, leading to higher and longer-lasting vitamin D levels.
This means it has a stronger effect on key processes like immune system support and calcium absorption.
Vitamin D3 is the better choice for people with MS so when choosing supplements check they say vitamin D3 (cholecalciferol) as well as the units they contain. For more information on how much vitamin D to supplement with head to our main page here.
Comparison of the Effect of Daily Vitamin D2 and Vitamin D3 Supplementation. This study compared the effectiveness of Vitamin D2 and D3.