Vitamin D plays a number of important roles in the body, so when we become deficient it has a big effect on our health and how well the body is able to function. It affects everything from your mood, your immune system, your cells, and your bones and muscles.

Vitamin D is known as the sunshine vitamin because it can be produced in the body with mild sun exposure. There aren’t many foods that contain vitamin D, so it is fairly easy to become deficient. This is especially true if you don’t consume the foods that contain vitamin D or spend a lot of time indoors. Those who live in a northern climate may also become deficient in vitamin D during winter months where days are shorter and sunlight is sparser.

Vitamin D supports several functions in the body:

• Its primary role is to support the development and maintenance of bones. It plays a large role in the regulation of calcium and maintenance of phosphorus levels, both of which are important for maintaining healthy bones.
• It supports your immune system and helps to fight infections, including colds and the flu as it regulates the expressions of genes that influence your immune system to attack and destroy bacteria and viruses. Getting adequate amounts of vitamin D can help you stay healthy during the cold and flu season.
• As an immune system modulator, it is important for the prevention of autoimmune diseases such as multiple sclerosis and inflammatory bowel disease.
• It can protect against cardiovascular disease. Vitamin D is important for reducing hypertension, heart disease, atherosclerosis, heart attack, and stroke.
• It has a large impact on the health and functions of cells. Vitamin D reduces cellular growth (which promotes cancer) and improves cell differentiation (which inhibits cancer).
• Vitamin D regulates and controls genes. This is why vitamin D controls so many different functions in the body.

Given the number of systems in the body that are impacted by vitamin D, being deficient can cause a number of health concerns. Vitamin D deficiency affects more than half of the population but is rarely diagnosed. Some symptoms of vitamin D deficiency include feeling blue or down, achy bones, and muscle weakness. You may also find that you more easily catch a cold or the flu.

There are steps you can take to prevent vitamin D deficiency.

• Enjoy some time in the sun. Almost all of the vitamin D we need comes from the sun, and just 10 minutes is all you need for your body to synthesize enough vitamin D.
• Consume foods that contain vitamin D, such as fish liver oils, wild salmon, mackerel, sardines, and eggs.
• If you’re unable to get enough vitamin D, it is important to include a quality vitamin D supplement into your daily routine to prevent becoming deficient.