Does sunscreen cause Vitamin D deficiency?
Vitamin D is essential in keeping bones healthy and strong and is generated in the body when the skin is exposed to UVB radiation from the sun. If we’re using high-level sun protection every day, does that hinder our ability to generate sufficient levels of Vitamin D? And is it linked to Vitamin D deficiency?
In short, the answer is no. But let’s explore this in more detail.
What do we need Vitamin D for, and how is it made?
Vitamin D regulates the amount of calcium and phosphate in the body, which are essential nutrients to help keep our bones, muscles and teeth healthy and strong.
Our bodies are able to generate Vitamin D when the skin is exposed to sunlight, specifically UVB radiation. The UV energy is absorbed into the skin, kick starting a chemical reaction that changes the Vitamin D precursor into bioavailable Vitamin D.
Without enough Vitamin D, the body can only absorb 10% to 15% of dietary calcium, but 30% to 40% absorption is the rule when vitamin reserves are normal.
How much sun do we need to generate sufficient Vitamin D levels?
UVB is only really present in the summer months and cannot penetrate clouds, so our exposure in the UK is limited.
However, on a sunny summer day in the UK you only need a short period of sun exposure (around 30 mins) with areas such as hands, arms and lower legs exposed for most people to create enough Vitamin D.
Those with darker skin types of Fitzpatrick V and VI are less able to generate Vitamin D from sunlight as the melanin in the skin helps to absorb UV rays and prevents its synthesis into Vitamin D.1
In the UK from October to early March there simply isn’t enough UVB present for our skin to be able to create Vitamin D.
Does daily use of sun protection cause Vitamin D deficiency?
It’s a common misconception that using sun protection daily will not allow you to make enough Vitamin D and will cause Vitamin D deficiency. There are no studies that suggest a link between the two, in fact, studies have shown that those who do use daily sun protection can maintain their Vitamin D levels.2
Furthermore, using sun protection products with high SPF such as 50+ won’t block all UVB rays, so you’ll still get some UV exposure.
In fact, by not using regular sun protection you are exposing yourself to a much greater risk to your health in the form of sun damage and skin cancer, so the best course of action is to find a way to protect your skin, whilst getting enough levels of Vitamin D.
So how do we get enough Vitamin D to stay healthy?
Vitamin D is found in food such as oily fish and red meat, but it can be difficult to get enough Vitamin D from food alone, which is why the NHS recommend that everyone should consider taking a daily Vitamin D supplement throughout the winter months. The EU daily recommended dose of Vitamin D is 5ug of Vitamin D whilst the UK recommends a daily dose of 10ug.
