Discovery of vitamin D
Vitamin D was one of 13 vitamins discovered in the early 1920s by a group of doctors researching diseases resulting from nutritional deficiencies, such as rickets. Since then scientists have defined vitamins as being carbon-containing chemicals that must be obtained through diet because they are not produced by the body’s tissues. These vitamins play a vital role in our body’s metabolism, but only very small amounts are needed for them to achieve their purpose.
What is vitamin D?
Although vitamin D is referred to as one of the four fat-soluble vitamins, it is unique from the other vitamins in that it can be synthesised by the human body and food sources of vitamin D are scarce (limited to fish and egg yolks). Even when obtained from food sources, vitamin D must be converted before the body can utilise it.
Vitamin D is produced by our skin from a type of cholesterol called 7-dehydrocholesterol. Sunshine (UVB energy) is the magic key which enables 7-dehydrocholesterol to be converted to vitamin D3, hence it is often referred to as ‘the sunshine vitamin’. Vitamin D3 is carried to the liver and then the kidneys where it is transformed into active vitamin D.
Given the lack of sunshine in the Autumn and Winter months in the UK, vitamin D deficiency is common, particularly amongst population groups with darker skin, or those who cover their skin, limiting exposure to sunlight. Sunscreens also prevent us from producing vitamin D, given our need for UVB energy for the conversion process to take place. This deficiency has been linked to a potential increased risk of developing a wide range of illnesses.
Vitamin D, light and energy
Let’s delve a little deeper into this relationship between vitamin D and light or energy from the sun and what it means for the human body and our health. What is really happening when we go on holiday somewhere warm and sunny to ‘recharge our batteries’?
