Didn’t autumn sneak up on us this year? It was lovely and sunny for so long, but suddenly the nights are cold and evening comes far too soon. Next Sunday the clocks will go back and it will be dark even earlier. Before long, many of us will see daylight only through our office windows.
But did you know that the amount of light we are exposed to considerably affects our body chemistry?
Among all the different vitamins there is just one our body can make: vitamin D. Vitamin D is made in the skin when it is exposed to sunshine, but for us in the Northern hemisphere it can be difficult to get enough sunlight even in the summer. During the winter months, when we are indoors most of the time and when outside wearing layers of clothing, it is harder still to make enough vitamin D. The fairer your skin, the more efficient your vitamin D production will be, the darker your skin, the harder it is. However in the UK, we all are most likely deficient.
A lot of research on vitamin D has been done in the last few years and we now know that it plays an important role in bone and cardiovascular health. It strengthens the immune system, supports muscle function, the respiratory system and protects from cancer. Moreover, vitamin D levels affect mood. If you are prone to depression, it is worth getting tested. Severe vitamin D deficiency causes a condition called rickets in children and osteomalacia in adults, both cause soft and brittle bones. Other conditions linked to low levels of vitamin D are asthma, Alzheimer’s disease, diabetes II, high blood pressure, and a number of autoimmune diseases including multiple sclerosis, Crohn’s disease and diabetes I.
Vitamin D is a fat-soluble vitamin. Any excess of water-soluble vitamins is excreted via the urine, but excess fat-soluble vitamins cannot be excreted and are stored. That means that toxicity is possible, so before taking a vitamin supplement it is best to get tested. Any nutritional therapist can arrange for a test. It is an affordable test that only requires a spot blood sample. Vitamin D is available as a supplement, and it doesn’t cost much.
While deficiency is likely and supplementation recommended for most of us, there are some conditions and medications with which vitamin D is counter-indicated, so please don’t just go and get a supplement: Check with your doctor or a nutritional therapist who is trained in the use of supplements.
There are a few food sources for vitamin D as well, but food alone cannot provide sufficient amounts. Vitamin D is contained in oily fish – fresh tuna, salmon, mackerel, herring, sardines – beef liver, egg yolks, some fortified foods such as milk, orange juice and cereals. If you are vegan, your only food sources are the fortified ones.
So during the dark winter months, try and get outdoors in the middle of the day whenever you can. Use your lunch break to go for a walk and expose as much skin as possible – weather permitting of course.
Do get tested, and if you find that you are deficient get a good quality vitamin D3 supplement.
Other chemicals dependent on light or the lack of it are the neurotransmitters serotonin and melatonin. These are active in the brain and affect mood, happiness, activity and sleep. During the dark winter months, we are not producing enough serotonin (for happiness and good mood) and too much melatonin (for sleep). In sensitive people this can result in a condition called “Seasonal Affective Disorder” (SAD), often referred to as “the winter blues”. More on this in next week’s blog – watch this space!