Winter is well and truly on its way. With the colder temperatures, comes the delightful cold and flu season. What you might not know, we are also at greater risk of Vitamin D deficiencies during winter. Vitamin D is essential food good health, it helps keep us healthy and able to fight infections. The irony is that in winter, we need Vitamin D the most, but most of us are not getting enough. With so many sun-filled days here in Australia, you would think a Vitamin D deficiency would be unlikely. Surprisingly, nearly one-third of Australians are deficient. The winter months mean fewer hours of sunshine, and for many of us it means leaving for work in the dark and coming home in the dark after spending all day in an office. Without the blue skies of summer, our skin is unable to soak up enough sunlight to create Vitamin D.

Why Vitamin D is Important for Winter

In the winter, we are exposed to more infections and spend less time in the sun. Vitamin D is essential for immune health as it helps reduce inflammation, build our resistance to illness, increase the amount of antimicrobial proteins, which destroy invading germs and viruses, and helps to fight infections more effectively. Studies have shown low levels of Vitamin D are associated with increased risk of viral and bacterial infections and susceptibility to illness. Interestingly, research also shows the link between Vitamin D status and upper respiratory tract infections, with results indicating a reduced risk of infection and severity in those with optimal Vitamin D levels.

Where to get your Vitamin D

The body’s main source of vitamin D comes from the skin being exposed to UV radiation in sunlight. When sunlight hits the skin, it reacts with a cholesterol-like substance and produces vitamin D. The amount of sun exposure needed depends on your skin colour, where you live and the time of year. As a general guide, it is best to expose your face, arms, hands, or legs for:

• 10 minutes in summer
• 5-20 minutes in spring and autumn
• 30 minutes in winter

Dietary sources of Vitamin D are limited and includes fatty fish such as salmon, tuna, sardines, and mackerel. There are small amounts in grass fed beef, cheese, and egg yolks. Some fortified foods like milk and processed cereals have Vitamin D added to them, but these would not be my preferred recommendation. It is important to note, Vitamin D is a fat-soluble vitamin, which means a diet low in fat may reduce its absorption. There are other vitamins and nutrients which help the body to absorb and use the vitamin, including magnesium, zinc, vitamin K and boron. So, it is important to ensure you have adequate levels of these too.

Do I Need to Supplement Vitamin D?

Vitamin D is stored in the body for around 2 months. Therefore, the Vitamin D you stocked up during the summer months will start fading away as the shorter and colder months roll in. Since it is hard to get adequate Vitamin D from food alone, the best option is to supplement with a high-quality Vitamin D to get your levels in the optimal range. Supplements typically come in two forms, Vitamin D3 or D2, with D3 being for efficient at raising levels in the body. It is important to note not all supplements are the same and the therapeutic dosage depends on your age, weight, health, and diet. The recommended dose for most adults needing to increase their Vitamin D levels is 4000 IU or more during the winter months. Don’t forget to take your Vitamin D supplements with a meal containing fat to improve absorption. You can check out our Vitamin D range here.