By Lynn Lamb —
Vitamin D is known to play a major role in the health of humans. The many functions of vitamin D include its ability to control blood pressure, its role in calcium absorption and its involvement in the development of healthy bone and teeth. More recently, it has been suggested that Vitamin D is also necessary for maintaining a healthy weight.
Vitamin D Deficiencies Research suggests that inadequate levels of vitamin D not only causes many health related problems but is associated with weight gain. University of Michigan researchers found that children having deficiencies in vitamin D accumulated fat around the waist and gained weight more rapidly than children who were not vitamin D deficient. (1). This type of fat gain has been associated with greater risk of type 2 diabetes and heart disease.
University of Southern California and McGill University Health Center researchers found that young women with a vitamin D insufficiency were significantly heavier and had an increased body mass than young women with normal vitamin D levels. The lack of vitamin D caused fat accumulation and increased risks of future chronic diseases (2).
Dr Helen Macdonald, of Aberdeen University’s department of medicine and therapeutics, suggests that obese people are just not getting enough sunlight and that the vitamin D they do have is going into fat stores and is not accessible (3).
Insufficient vitamin D in the blood interferes with the hormone leptin, which signals to the brain when the stomach is full (3).
Sources of Vitamin D The most common source of Vitamin D comes from ultraviolet sun rays. The ultraviolet rays are absorbed through the skin. The amount of Vitamin D produced in the body is determined by absorption levels.
The sun’s ultraviolet rays are strongest closest to the equator and at high elevations. Absorption of Vitamin D decreases the further from the equator you get. Individuals with darker skin absorb less Vitamin D than those with lighter skin; younger individuals absorb more Vitamin D than older individuals. Individuals that avoid sunlight by remaining inside or by staying covered up when outside will have limited Vitamin D absorption. Age, skin color, clothing, exposure time and where you live all determine the amount of Vitamin D your body will be able to produce.
Vitamin D can also be found in some foods. It occurs naturally in fatty fish, fish liver oil and egg yolks. Salmon, mackerel, herring, trout, sardines and tuna also contain Vitamin D. Milk and dairy products, orange juice, breakfast cereals, bread and soy products are often fortified with Vitamin D.
Vitamin D Requirements There has been controversy around the amount of Vitamin D required for healthy living. However, there is agreement that the tolerable upper level of intake is 2000 international units (IU) per day for anyone over one year (4). Health Canada suggests the adequate intake of Vitamin D for anyone under 50 years old is 200 IU, 400 IU for individuals from 51 to 70 years old and 600 IU for anyone over 70 years old (5).
Ensuring that you get the enough Vitamin D is an essential component for everyday health including maintaining a healthy weight. Enjoy the sun and make some Vitamin D today.
References 1. University of Michigan. “Low Blood Levels of Vitamin D Linked to Chubbier Kids, Faster Weight Gain.” ScienceDaily, 8 November 2010. Web. 8 November 2010. http://www.sciencedaily.com¬ /releases/2010/11/101108161228.htm?utm_source=feedburner&utm_medium=feed&utm_campaign=Feed%3A+sciencedaily+%28ScienceDaily%3A+Latest+Science+News%29&utm_content=Google+International
2. McGill University Health Centre (2008, December 11). Lack Of Vitamin D Causes Weight Gain And Stunts Growth In Girls. ScienceDaily. Retrieved November 8, 2010, from http://www.sciencedaily.com/releases/2008/12/081210122238.htm
3. Current TV: Exposure to sunlight may be key to weight loss. http://current.com/news/89103283_exposure-to-sunlight-may-be-key-to-weig…
4.Health Canada. Vitamin D Recommendation and Review Status. http://www.hc-sc.gc.ca/fn-an/nutrition/vitamin/vita-d-eng.php