The Benefits of Vitamin D

Vitamin D and Bone Health

Vitamin D is a nutrient that has a number of important health benefits. Studies show that it helps with bone health. However, the committee that established the DRIs for vitamin D found that the evidence is insufficient and conflicting. So, they recommended DRIs for vitamin D, which are only sufficient for bone health.

Vitamin D3

While a diet high in vitamin D can have many benefits, a lack of vitamin D can lead to bone problems. In addition to a decreased risk of fractures, vitamin D can also protect against heart disease, myocardial infarction, and stroke. Research has shown that taking a vitamin D supplement can lower your risk for high blood pressure.

Role of Vitamin D

Vitamin D is fat-soluble and is necessary for the body's absorption of calcium. It also helps your body absorb phosphorus and magnesium, which help support muscle function and energy levels. In addition, vitamin D can strengthen your immune system by inhibiting the production of inflammatory cytokines. These signals the immune system to start fighting infection.

Sources of Vitamin D

Vitamin D can be found naturally in some foods, but most people don't ingest large quantities of it. The best sources are the flesh of fatty fish liver oils. Other sources include egg yolks and beef liver. Certain mushrooms can also be a good source of vitamin D, though they are higher in vitamin D2 than vitamin D3. Foods fortified with vitamin D are available in many different forms.

Supplementation of Vitamin D

Recent studies have revealed that adequate supplementation of vitamin D is difficult in critically ill patients, due to pharmacokinetic variability and perturbations in the pathophysiology. Despite the challenges of delivering sufficient doses of vitamin D to the patient, some studies have demonstrated an increase in 25-hydroxy-D levels in critically ill patients. In a single study, an enteral ultra-high-dose (540,000 IU) of vitamin D3 administered once normalized the 25-hydroxy-D levels of 80% of patients in a medical ICU. Similarly, Mata-Granados et al. found a significant increase in 25-hydroxy-D levels in a group of 33 critically ill patients with sepsis.

Effect of Vitamin D on Certain Conditions

Recent epidemiological studies have suggested that insufficient vitamin D levels may increase the risk of certain conditions. Nonetheless, the results of these studies are contradictory. Many of the trials incorporated different subgroups, had different baseline levels, and used varying doses. However, the majority of studies found a beneficial effect of vitamin D supplementation in patients with cancer, although the benefit was not as significant in those with lower vitamin D levels.

Health Effects of Vitamin D

Vitamin D is often associated with strong bones and teeth, as it regulates calcium levels in the body. But it also plays an important role in the prevention of major diseases. In fact, studies have linked Vitamin D to the prevention of cardiovascular disease, type 1 diabetes, and even cancer. Over the last 25 years, scientists have been investigating Vitamin D's health effects. One of the leading experts on the subject is Dr. David Feldman, who has spent his career researching the benefits of vitamin D.

Vitamin D Deficiency and Bone Health

Studies have shown that low levels of Vitamin D in the body result in weaker bones and lower bone density. A lack of vitamin D is a major risk factor for bone fracture. Vitamin D deficiency affects bones by preventing them from mineralizing. This process is necessary for bone formation and determines the hardness and strength of bones. Vitamin D deficiency significantly affects rapidly growing bones. Growth plates continue to enlarge. Bones become deformed, and the rib cage can develop abnormalities. Vitamin D deficiency can also cause seizures and delayed closure of fontanels.

Tolerable Upper Limit and Sources of Vitamin D

According to the Institute of Medicine (IOM), the tolerable upper limit of vitamin D in adults is 4,000 IU. Higher doses may damage kidney function and cause other negative effects.

There are a number of food sources of vitamin D. Fatty fish such as salmon and tuna, as well as egg yolks, are all good sources. Milk, particularly commercially fortified milk, is a major source. A cup of milk contains about 100 international units of vitamin D. You can estimate how much vitamin D you need per day by multiplying the number of cups of milk by 100. For example, a person needs two cups of milk per day to get the recommended daily allowance of 100 IU. Additionally, many cereals are fortified with vitamin D.

Vitamin D is also found in fortified foods such as orange juice, yogurt, and fatty fish. However, many people are not getting enough of this vital vitamin in their diet. In fact, in 2013, about 3.2% of U.S. adults took vitamin D supplements containing more than 1,000 IU.