The officials still called it summer. Not many of the rest of us did. The lowest maximum temperature was 13°C in Melbourne. Laugh away the rest of you. Overall maximum temperatures were down in many parts of the country (www.bom.gov.au).
Apparently the “girl-child” or La Nina caused this temperature change. How does this relate to nutrition and a Dietitians blog? The outcome for many of us was reduced exposure to the sun over summer and this puts us at risk of low vitamin D levels when the real winter hits.
Vitamin D is made by the body from exposure to the sun. In the southern states of Australia, we typically build up our levels with higher exposures over summer and levels reduce as we cover up more over winter. This often leads to low vitamin D levels by the end of winter (Med J Aust. 2001 Oct 15;175(8):401-5). When this happens, suddenly having enough vitamin D in your diet becomes important because when there is not enough sun, your body relies on vitamin D from food.
In food, Vitamin D is found naturally in eggs and oily fish, but it also may be added to some foods including margarine, butter spreads and milk. To find out if your margarine, milk or butter has vitamin D, check the ingredients list. Vitamin D will be listed as an added ingredient. As it is only added in small amounts it will probably be the last ingredient listed. Here is an Ingredients list from Meadow Lea “Buttery” that shows added vitamin D (and A) as the last ingredient:
Vegetable oils 60% (containing 47% canola oil), water, salt, emulsifiers [471, 322 (from soy], milk solids, preservative (202), food acid (270), natural flavour, natural colour (160a), vitamin A & D.
The other way that many of us will rely on to get enough dietary vitamin D over winter is a supplement.
This blog is reflecting on less sun exposure over the summer gone and I am not advocating sun exposure without consideration of skin cancer risk. Excellent resources on this fine balance are the SunSmart App (android and iOS) for advice on UV levels and skin protection and the Cancer Council summary at https://www.cancer.org.au/cancer-information/causes-and-prevention/sun-safety/preventing-skin-cancer
If La Nina meant more clothing worn over your recent summer, then maybe it is worth having vitamin D on your radar over winter.
Apparently La Nina is starting to weaken. Let’s make sure your vitamin D health doesn’t.