Vitamin D is an essential vitamin for keeping you healthy and well. Despite the vital importance of vitamin D, most of the foods we eat contain little or no vitamin D. Milk – particularly fortified milk – is a good source of vitamin D, but consuming cow’s milk is not suitable for everyone. A liquid vitamin D supplement is a good alternative to milk as a source of vitamin D.

Vitamin D is very important for bone growth and calcium absorption, and long-term deficiency of vitamin D can even lead to osteoporosis in later life. Children who do not get enough vitamin D can develop rickets, in which the legs bow outwards and become weak. Vitamin D is also a natural anti-inflammatory substance, and there is a lot of research going on to find out whether vitamin D consumption could help to relieve the symptoms of a wide range of conditions, including arthritis and multiple sclerosis. Studies suggest that vitamin D could also play a role in preventing certain types of cancer, particularly breast, prostate and colon cancer.

Very few foods contain vitamin D. One of the best sources of vitamin D is oily fish, but most people do not eat enough of the right types of fish to get the full recommended amount of vitamin D. Dairy products naturally contain a small amount of vitamin D, but eating too many high-fat dairy products can lead to obesity, which can have devastating health consequences.

Milk in the United States is usually fortified with vitamin D. However, many people cannot drink milk because of lactose intolerance or dairy allergy. For these people, a liquid vitamin D supplement is a good alternative.

The other source of vitamin D is sunshine. Cells in your skin produce vitamin D whenever they are exposed to the sun. However, for people who live in cold climates, daily sun exposure is not always possible, particularly during the winter months when daylight hours are relatively short. Many people choose to take a liquid vitamin D supplement during the winter to make sure they get enough of this vital vitamin.

Even if you live in a sunny climate, you might not get all the vitamin D you need from sunshine. Sunscreen blocks the radiation that triggers vitamin D production, but going without sunscreen is not recommended because you could increase your risk of skin cancer by exposing your skin to the sun without protection. People with dark skin make less vitamin D than pale-skinned people because the pigmentation in their skin blocks out the radiation that triggers the body to produce vitamin D. Living in a sunny climate does not necessarily mean that you get enough vitamin D – you may still need a liquid vitamin D supplement.

Vitamin D supplements are most important for people who don’t eat fish or milk, such as vegetarians and vegans. Even people who do eat these foods may want to take a liquid vitamin D supplement to protect against osteoporosis.

Derek Finch is a freelance writer who focuses on health, fitness, nutritional science, medicine and other related matters.