At this time of the year, along with making seasonal wardrobe changes and craving hearty meals, the impact of longer days and shorter nights, is also a time to reflect on our health, particularly our vitamin D levels.
With the changing of the clocks a few weeks ago, the reality for us in the UK includes the disconcerting fact that we start and end our day in darkness and as the evenings draw in, it can play tricks on the body.
The vast majority of the vitamin D in our bodies comes from our skin’s unprotected exposure to sunlight. To support a normal, effective immune system, we need the essential nutrients that regulates the intake of our bodies calcium, magnesium and phosphorous which are vital minerals required, among other things, for the formation of healthy bones.
Vitamin D also supports muscle function, allowing us to stay active by enhancing mitochondria – the ‘powerhouses’ of our bodies’ cells – which are responsible for turning energy from the food we eat, into energy for those cells.
During the months of October and early March, the lack of sun greatly reduces the amount of natural sunlight that we absorb and so it might be an idea to access whether you need to look into vitamin supplements to maintain, or boost, your levels. This mineral can also be found in a small number of foods, such as oily fish, red meat, egg yolks and fortified cereals, to name a few.
“People with dark skin, such as those of African, African-Caribbean or south Asian origin, will need to spend longer in the sun to produce the same amount of vitamin D as someone with lighter skin.”
In particular, there are a number of groups that are particularly susceptible to being ‘at-risk’ of deficiency. The deficiency is particularly prevalent in people with darker skin as we have a natural barrier towards the UVB rays needed to penetrate the skin. We call this natural barrier melanin.
Melanin is the term used for a group of natural pigments that affect how light or dark your skin colour is, the more melanin you have, the darker your skin colour. This melanin competes with vitamin D in the skin for UVB absorption, meaning that darker skin types allow less UVB to enter the skin and consequently produce less vitamin D.
In a nutshell, according to the NHS, “People with dark skin, such as those of African, African-Caribbean or south Asian origin, will need to spend longer in the sun to produce the same amount of vitamin D as someone with lighter skin.”
How would you know that your vitamin D levels are low? Simone describes her experience: “I frequently have low mood and as the night’s get longer, I feel I am becoming tired for long periods of time. This made me suspect I may be deficient, so I tested my levels.
“Knowing that my heritage puts me at a higher risk of being vitamin D deficient, due to the melanin in my skin reducing vitamin D production, as well as discovering that I have insufficient levels of vitamin D, definitely impacts my attitude towards my nutrient intake.” Simone opts to regulate her vitamin D levels by using supplements like the BetterYou range.
While current dosage recommendations do not differentiate between ethnic groups, The Department of Health recommends that people with darker skin take vitamin D supplement all year round, with the Institute of Medicine setting a safe upper limit of 4000 IU per day for healthy adults.
Please consult your doctor if you have any concerns about your health.