Vitamin D deficiency tends to affect Britons during this time of year because the sun is in short supple and UV levels are low.
This vitamin is important as it helps regulate the amount of calcium and phosphate in the body to keep bones, teeth and muscles healthy.
A vitamin D deficiency can cause symptoms such as bone and back pain, hair loss and fatigue.
Severe vitamin D deficiency can lead to loss of bone density and contribute to fractures. So what can you do to avoid it?
There are five ways recommended to help you avoid vitamin D deficiency when levels are low, according nutritionist Karen Langston, a spokesperson for the National Association of Nutrition Professionals.
Speaking to Arthritis Foundation she said these include eating more fish and simply opening a window.
She said: “Many types of fish are a good source of vitamin D. Three ounces of wild salmon or Atlantic mackerel can give you the recommended daily amount of vitamin D.”
Eat fortified foods
She advised: “Some foods, such as cereals, milk, cheese and soy products, have extra vitamin D aded in. Read your labels to find the ones with the biggest vitamin D boost.”
She said: “Remember when cod liver oil waist every medicine cabinet? Well it contains lots of vitamin D. One tablespoon contains as much of this strong-vine nutrient as three servings of salmon or mackerel.”
“Expose yourself, or even just your hands, to sunlight without sunscreen for just 10 to 15 minutes every other day,” said Karen.
She added: “Although the amount go sunlight required has been debated, the sun activates vitamin D production in your body. So if you stand in the sunlight, sit on a bench or take a quick stroll, you’ve turned on your vitamin D switch.
“Keep in mind that if you have darker skin, you need more sunlight to spark vitamin D production because darker skin doesn’t absorb sunlight as well as lighter skin.”
Open a window
She advised: “If you can’t get outside, sit by an open window or door for a few minutes, because most windows block the part of the sunlight needed to ignite vitamin D production.”
Insufficient levels of vitamin D can cause symptoms such as constipation and increased susceptibility to infection.