What is vitamins d

In another study , overweight people who took a daily vitamin D supplement improved their heart disease risk markers. Many factors can affect your ability to get sufficient amounts of vitamin D through the sun alone.

These factors include:. These factors contribute to vitamin D deficiency in an increasing number of people. Doctors can diagnose a vitamin D deficiency by performing a simple blood test. If you have a deficiency, your doctor may order X-rays to check the strength of your bones.

If you have a severe deficiency, they may instead recommend high-dose vitamin D tablets or liquids. You should also make sure to get vitamin D through sunlight and the foods you eat. Few foods contain vitamin D naturally. Because of this, some foods are fortified. This means that vitamin D has been added. Foods that contain vitamin D include:. It can be hard to get enough vitamin D each day through sun exposure and food alone, so taking vitamin D supplements can help. There has been some controversy over the amount of vitamin D needed for healthy functioning.

Recent research indicates that you need more vitamin D than was once thought. Normal blood serum levels range from 50 to micrograms per deciliter. Depending on your blood level, you may need more vitamin D. IUs are a standard type of measurement for drugs and vitamins.

Vitamin D plays a significant role in the regulation of calcium and maintenance of phosphorus levels in the blood. These factors are vital for maintaining healthy bones. People need vitamin D to allow the intestines to stimulate and absorb calcium and reclaim calcium that the kidneys would otherwise excrete. Vitamin D deficiency in children can cause rickets , which leads to a severely bowlegged appearance due to the softening of the bones.

Similarly, in adults, vitamin D deficiency manifests as osteomalacia , or softening of the bones. Osteomalacia results in poor bone density and muscular weakness.

A vitamin D deficiency can also present as osteoporosis , for which over 53 million people in the United States either seek treatment or face an increased risk. A review of existing research suggested that some studies had found that vitamin D had a protective effect against the influenza virus. However, the authors also looked at other studies where vitamin D did not have this effect on flu and flu risk. Further research is, therefore, necessary to confirm the protective effect of vitamin D on the flu.

Vitamin D deficiency has links to high blood pressure in children. One study found a possible connection between low vitamin D levels and stiffness in the arterial walls of children.

An example of this is children who live closer to the equator and have lower rates of admission to hospital for allergies plus fewer prescriptions of epinephrine autoinjectors. They are also less likely to have a peanut allergy. Eggs are a common early source of vitamin D.

The children who started eating eggs after 6 months were more likely to develop food allergies than children who started between 4—6 months of age.

Furthermore, vitamin D may enhance the anti-inflammatory effects of glucocorticoids. This benefit makes it potentially useful as a supportive therapy for people with steroid resistant asthma.

Its anti-inflammatory, antioxidant and neuroprotective properties support immune health, muscle function and brain cell activity. Vitamin D isn't naturally found in many foods, but you can get it from fortified milk, fortified cereal, and fatty fish such as salmon, mackerel and sardines.

Your body also makes vitamin D when direct sunlight converts a chemical in your skin into an active form of the vitamin calciferol. The amount of vitamin D your skin makes depends on many factors, including the time of day, season, latitude and your skin pigmentation.

Depending on where you live and your lifestyle, vitamin D production might decrease or be completely absent during the winter months. Sunscreen, while important to prevent skin cancer, also can decrease vitamin D production.

Many older adults don't get regular exposure to sunlight and have trouble absorbing vitamin D. If your doctor suspects you're not getting enough vitamin D, a simple blood test can check the levels of this vitamin in your blood. Taking a multivitamin with vitamin D may help improve bone health. The recommended daily amount of vitamin D is international units IU for children up to age 12 months, IU for people ages 1 to 70 years, and IU for people over 70 years.

Without vitamin D your bones can become soft, thin and brittle. Insufficient vitamin D is also connected to osteoporosis. If you don't get enough vitamin D through sunlight or dietary sources, you might need vitamin D supplements. However, taking too much vitamin D in the form of supplements can be harmful. Children age 9 years and older, adults, and pregnant and breastfeeding women who take more than 4, IU a day of vitamin D might experience:. Fracture prevention with vitamin D supplementation: a meta-analysis of randomized controlled trials.

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