Modern Day Vitamin D deficiency in a westernised culture: unpicking the scare mongering about rickets
Rickets for most of us is something of the past, something you don’t hear of occurring anymore particularly in western cultures. However, recently scare mongering in popular news repositories have been name dropping the historical bone disorder more and more. One eye catching article stated that children who stay inside on computers and parents who apply sun screen excessively to their children in sunny and hot weather is leading directly to sharp increases in bone disease and rickets.
It’s important to remember that these articles are meant to be shocking to read, in order to get more views, and while there is some truth in this it’s embellished to give more of a punch, leaving us very confused. While at the same time we are being told that excessive sun exposure is extremely dangerous, we are also being told our children will develop bone disease if they don’t go in the sun at all? Let’s unpick that one.
Vitamin D is a unique vitamin because it can be synthesised from exposing our skin to the sun. The Vitamin D Receptor (VDR) which synthesises vitamin D from sunlight is present in most cells. Because of the way vitamin D is made in the body, a major cause of vitamin D deficiency is not enough exposure to sunlight, this could be from not spending enough time in the sun at all or from wearing sun screen too much of the time. Some research has shown that wearing an SPF of 30 can decrease Vitamin D production by up to 95%.
While it is incredibly important to be safe in the sun especially with little ones who have often fairer and more sensitive skin than adults, it’s also important that you and your children get enough sun exposure to produce vitamin D. One of the reasons why vitamin D is so important for bone health is because it stimulates calcium absorption in the intestine. Without vitamin D, calcium absorption is impaired to only about 10-15% being absorbed into the blood. It’s also important to remember that the sun is the main source of vitamin D and that dietary absorption is minimal. Yes, that includes fromage frais with added vitamin D!
You might be thinking all of this is well and good, but how do we safely expose our children to the sun so that they get enough Vitamin D to have healthy bones? It’s all about minimising risks of sun exposure whilst maximising the benefits. As the strength of sunlight varies at different times of day, so does the ability for the skin VDR’s to synthesise vitamin D.
The sun is most intense between 11am and 3pm, so at these times, its easiest to synthesise vitamin D so less time is needed in the sun. this is also the time when sunburn is most likely to occur, so short periods of time spent in the sun are best, and also only exposing areas of the skin least likely to burn such as forearms, hands and lower legs.
Before 11am and after 3pm the sun is less intense so you’re less likely to burn, but it takes longer to synthesise vitamin D. Young children should also seek shade between 11 and 3 in the summer months (March to October) and wear protective clothing to cover areas likely to burn, such as a brimmed hat to cover the face and neck. As long as you are careful in the sun you can maximise vitamin D exposure for your little ones, making sure they get enough without getting burned or damaging their skin.
Phoebe BSc (Hons) Nutrition