Today we celebrate the winter solstice – the shortest, darkest day of the year, roughly marking the mid-way point of 2018. From tomorrow onwards, the hours of darkness will slowly dissipate as the sun shines her magnificent rays down on earth, giving life and nourishing us dwellers of the Southern Hemisphere. The sun contributes largely to our overall feeling of happiness and vitality by supplying us with Vitamin D.
Vitamin D isn’t actually a vitamin or nutrient; it is a hormone produced from a photolytic reaction with ultraviolet (UV) light. It is essential for nearly every single bodily system and function including the musculoskeletal, gastrointestinal, renal, endocrine, and cardiovascular systems. At a minimum, Vitamin D maintains bone health by helping your body absorb calcium. A deficiency over a prolonged period of time can lead to a loss in bone density and a higher likelihood of fractures and falls as you age, as well as the development of chronic illnesses. Vitamin D is essential for the normal and healthy functioning of the immune system. When adequate levels of Vitamin D are not maintained, the microglia — the immune cells of the central nervous system that initiate temporary inflammatory responses to attack foreign invading organisms, are unable to function optimally. As a result, people with low levels of Vitamin D can be at a higher risk of developing a host of inflammatory conditions.
Often nicknamed “the sunshine vitamin,” Vitamin D mostly enters our bodies via the sun, which is absorbed by our skin and converted to a usable form by cholesterol. One role of Vitamin D is its effect on Serotonin production. Serotonin is a brain chemical that helps control mood and anxiety. When your Serotonin system is running low, you are prone to be more irritable, anxious, sad or depressed. The ‘winter blues’ are REAL, largely due to the lack of Vitamin D we experience over the cooler months. In fact, Vitamin D deficiency affects over half the population, rarely goes diagnosed, and has been linked to many cancers, high blood pressure, heart disease, diabetes, depression, fibromyalgia, chronic muscle pain, bone loss, and autoimmune diseases like multiple sclerosis.
Vitamin D levels change naturally with the seasons. How much UV exposure a person needs depends on the time of year, their skin type and their existing Vitamin D levels. While the sun is the best natural source of Vit D, ultraviolet radiation is the main cause of skin cancer so be wary of harnessing your dosage safely.
Here are some effective ways to get your Vitamin D intake
Exposure to the sun is safest before 10 am or after 4 pm
Being physically active outdoors – take a walk outside (rather than the gym)
Have your morning tea/coffee in a sunny spot
Wear clothing that exposes some of your skin for optimal absorption
Commute to work via bicycle or foot to maximise sun exposure
Note that the body can only absorb a limited amount of vitamin D at one time so it’s important to dose it regularly with short stints, that way maintaining a steady flow while avoiding risks associated with over-exposure. Experts say that approximately 5 to 10 minutes per day outside without sunscreen, two to three times a week, can help you maintain adequate levels.