Why supplement with vitamin d3 latest government statistics have shown that vitamin d is the nutrient of most concern in britons. This is due to 29% of adults and 37% of children aged 11-18 having levels that indicate a clinical deficiency. Although we can synthesise vitamin d through sunlight, we all appreciate that good weather, even during the summer months, is not guaranteed. Because of this, and for the fact that foods containing vitamin d are sparse, the department of health recommends that everyone considers a 400iu 10 g vitamin d supplement through the months of september to april. 'At risk' groups such as older adults and those with dark skin are encouraged to take a supplement year-round. Expert support for vegans standard vitamin d3 has traditionally been sourced from lanolin, meaning it is suitable for vegetarians but not vegans. Simply supplements have chosen pine as a natural, plant-based source of vitamin d3, offering a vegan-friendly solution to help maintain healthy levels of this essential nutrient. Although vitamin d2 is usually vegan-friendly, it is widely accepted to be less effective and bioavailable than d3. The main role of vitamin d in the body is helping the body absorb and utilise calcium. Thus, vitamin d has an important role in bone and muscle function. It is also a key contributor to a healthy immune system, which is an important consideration, especially during the colder, darker months.