Around 30% of New Zealanders are deficient in vitamin D. Vitamin D is essential for aiding in the absorption of many minerals that our bodies need, especially calcium and phosphorus. Deficiency can lead to a number of symptoms such as fatigue, muscle pain and weakness, weight gain, sleep problems, migraines, depression, high blood pressure, as well as joint pain and reduced bone density. You can get tested for vitamin D deficiency – 25-hydroxy-vitamin D is the main form of vitamin D tested for. Blood levels below 25 nmol/L (10ng/ml) are considered low and 50 nmol/L is generally considered normal.
It is impossible to get enough vitamin D from your diet alone. Supplementation is one option, but our primary source of vitamin D is from the sun. Our skin absorbs sunlight and synthesises vitamin D, similar to the process of photosynthesis in plants. We have been told for decades that the sun will give us skin cancer and to avoid it as much as possible, and pile on the sunscreen. Unfortunately vitamin D deficiency is all too common – at any age – and sunscreen inhibits your absorption of vitamin D. Research now shows that controlled, safe exposure to the sun is not only your best source of vitamin D but actually decreases your chances of getting most cancers, including melanoma, as vitamin D influences the expression of genes involved in cancer development.
Vitamin D has many more positive health benefits. Vitamin D is essential in maintaining healthy bones and teeth, brain and nervous system, supporting the immune system’s ability to fight colds and flus, regulating insulin levels, supporting lung and heart health and metabolic processes, and it even helps fight autoimmune diseases.
A study by Auckland University, published in early 2016, showed that vitamin D supplementation in pregnant women leads to a reduction in the incidence of childhood allergies and allergy-related asthma. A new Danish study, published in The Australia & New Zealand Journal Of Psychiatry, has discovered a clear link between vitamin D deficiency in pregnant mothers and their children developing ADHD.
The sun is your best source
So now you know the importance of vitamin D, what are the best ways to get it? The sun is your best source, but getting burnt is counter-productive. If you go out in the sun this summer, it’s ideal to expose your skin to the sun for short periods regularly – in New Zealand around 10 minutes a day. If it’s appropriate, take your shirt off so as to get a bit of sun on those parts of your body that don’t usually see it. Although we’ve been told to avoid the sun in the hottest part of the day, this advice has actually contributed to vitamin D deficiency. Between about 11am and 3pm is the best time to do your vitamin D synthesising, as long as you don’t overdo it.
Interestingly, the highest incidence of skin cancer seems to be in people who rarely get any sun but get large doses occasionally, for example on their annual summer holiday. It’s hard to get enough sunlight exposure during the winter months, but in summer it’s all too easy. The key is to strike a balance by getting small amounts of sun daily, rather than bingeing. So, if you’re planning your summer holiday, don’t think “oh, I’ll be able to catch up on all the vitamin D I’ve missed out on during the year” – it doesn’t work like that!! Try to make time in your normal routine to get a bit of sun each day. Depending on the time of year and which part of the world you live in, about 5-30 minutes of sun a day is beneficial. If you’re going to be out in the sun longer than that, make sure you cover up with clothing, wear a hat to protect your face and neck and keep to the shade during the middle of the day. Wear sunscreen only when you have no other option, and choose a non toxic brand.
If you suspect your vitamin D levels are low (for example, if you tend to get the winter blues or experience fatigue or other symptoms mentioned at the beginning of this article), it might be worth taking a supplement. Lester’s Oil is an omega-3 formula that contains the maximum amount of Vitamin D3 currently allowable in a NZ supplement, along with Coenzyme Q10 (for heart and brain health, as well as energy), lutein and zeaxanthin for eye health and astaxanthin, one of the most powerful antioxidants known.