Vitamin D is composed of fat- soluble secosteroids that are required by the body for aiding in the regulation and absorption of both calcium and phosphorus. It is different from other vitamins in that it can be ingested (D2 and D3), and because it can be taken in through your skin through increased exposure to sunlight. Vitamin D is often referred to as the “sunshine vitamin” for obvious reasons. Vitamin D’s most important trait is that it is responsible for inhibiting bone deficiencies, but it is also used for lowering mortality rates, reducing premature aging, preventing cardiovascular disease, and boosting the immune system.
Vitamin D can be found in small amounts in a number of foods including different types of fatty fish like herring, mackerel, sardines and tuna. Fortified Vitamin D is also found in cereals, juices, and various dairy products like milk and yogurt. Many non-dairy foods, like soy milk and almond milk, also contain Vitamin D, but it is in the form of D2 (Drisdol), which is a synthetic form of this vitamin. It is important to know that Vitamin D2 vs D3 have some important differences in their effectiveness. Overall, D3 is approximately 87% more potent and is converted 500 times faster into usable vitamin D. In fact, research suggests that Vitamin D2 may cause more harm than good when consumed.
These types of sources of Vitamin D only account for 15-20% of our Vitamin D intake. The vast majority of Vitamin D actually comes from exposure to ultraviolet rays. Amazingly, studies have shown that only 10 minutes of exposure to sunlight is necessary on a daily basis to prevent Vitamin D deficiencies. It was also discovered that for times when it isn’t possible to acquire adequate amounts of sunlight, it only takes 3 days of casual sunlight exposure to make up for 25 days without being in the sun. After being in the sunlight for a period of time, and Vitamin D is restored, the body continues to store Vitamin D in fat cells for later use.
Vitamin D has also been credited for prevention and treatment of a rare bone deficiency disease known as rickets. Vitamin D aids in absorption of calcium which helps bones become denser, reducing risks of fractures and breaks. Another bone disease that is mostly present amongst the elderly is osteoporosis. Increasing their intake of Vitamin D can help elderly individuals reduce bone loss, prevent falls resulting in fewer bone fractures and breaks. Vitamin D also works in the same way to treat people with hyperparathyroidism where bones are also very brittle and easily broken.
Further health benefits of Vitamin D that aren’t particularly bone related include improving heart health by treating high blood pressure and high cholesterol. Vitamin D also aids in improving diabetic health, obesity, muscular deficiencies, multiple sclerosis, rheumatoid arthritis, chronic obstructive pulmonary disease, asthma, bronchitis, premenstrual syndrome as well as tooth and gum disease. Vitamin D also boosts the immune system preventing autoimmune disease and has been linked to preventing some types of cancer. Below are the recommended dietary allowances for Vitamin D as instituted by the United States Institute of Medicine:
- People between the ages of 1 and 70- 600 IU/Day
- People over the age of 71- 800 IU/Day
- Women pregnant or lactating- 600 IU/Day