Vitamin D is also known as the "Sunshine Vitamin" because the body produces Vitamin D naturally in response to sunlight. Recent surveys have found that approximately 1 in 6 adults living in the UK have low levels of vitamin D in their blood due to inadequate exposure to natural sunlight, particularly during the winter months. The government therefore advises everyone to consider taking a vitamin D supplement between October and March to help keep bones and muscles healthy. Vitamin D is vitally important for the normal function of the immune system, which helps to reduce the risks of colds and viruses, particularly during the colder months. Our immune systems are our first line of defence against infection and disease and a deficiency in vitamin D can lead us to be more susceptible to falling ill. Vitamin D helps to reduce infection by binding to key receptors in the body which help promote immune response. Vitamin D contributes to the normal function of the immune system (claim substantiated by the EFSA.) Vitamin D is also essential for the maintenance of normal bones and muscle function. Without vitamin D our bodies cannot effectively absorb Calcium from the food we eat, which is essential to ensuring strong bones. It also ensures the correct renewal and mineralisation of bone. Vitamin D is also incredibly important for ensuring we have healthy smiles as it contributes to the maintenance of normal teeth (claims substantiated by the EFSA.)