‘As we head into winter, it’s an important consideration’: what’s the deal with vitamin D?

Health experts suggest that in Australia’s high-UV climate, 30-60 minutes of sun before 11am or after 3pm in winter is a good way to balance the need for sunlight with the risks of over-exposure. Photograph: Tim Robberts/Getty Images

As winter sets in and Australians living in the southern states don scarves, beanies and puffer jackets, many are bracing for a season of colds and flu. Being a season that also tends to bring less sun exposure, winter is associated with lower vitamin D levels, which our bodies derive mainly from the sun. And while this is known to impact bone health, there is growing evidence that vitamin D’s functions could be more extensive, with deficiencies linked to greater risk from respiratory infections.

“When our vitamin D levels are extremely low, they can cause muscle aches and pains of the body and can impact the immune response to infections,” says Vicki Kotsirilos, associate professor at Western Sydney University. “So as we head into winter, it’s an important consideration.”