What is Vitamin D Deficiency?Vitamin d deficiency refers to the state of lacking enough vitamin D in the body. This deficiency results from lack of enough exposure to sunlight, lacking to take supplements and the body needing more than average vitamin D, such as in cases of obesity and pregnancy. The deficiency is more prone to people that are overweight, pregnant, those who spending a significant amount of time indoors, older adults, individuals with inflammatory bowel disease, and breastfed infants provided the nursing mother is deficient in Vitamin D. In general, Vitamin D is essential for strong bones, protection against various health problems, including obesity. Vitamin D has other roles in the body, including modulation of cell growth, neuromuscular and immune function, and reduction of inflammation (NIH Office of Dietary Supplements).

Vitamin D Deficiency Symptoms

The symptoms of vitamin d deficiency may differ from person to person, and also in regard to the extent of deficiency. One of the symptoms is pain in the bones. This leads to weakness which makes it difficult to move around. Tiredness and general aches may also be experienced. Depression and muscle pain are also symptoms of vitamin d deficiency.

Low Vitamin D and Weight Gain

A combination of a hormone called Leptin and Vitamin D work together to regulate body weight. In general, most people can have the same body weight for years. However, to have a constant weight, there must be a consistent energy intake, expenditure, and balance. But when that energy balance is disturbed, this can eventually lead to sustained weight problems. Leptin is a mediator and regulator of long-term energy balance, suppression of food intake and thereby inducer of weight loss. The body’s fat cells produces Leptin and it works by transmitting signals to the brain that let’s the body know when it is full and to stop eating. In function, Leptin is released into the circulatory system by the adipose tissue as a function of the energy stores. After release by the adipose tissue, leptin signals to the brain, giving information about the status of the body energy stores (Klok, 2006). Vitamin D in the body helps the Leptin signal work properly in the body. However, when the body’s Vitamin D deficient, that signal is disrupted and does not transmit properly and the body does not receive the proper signals that would typically alert the individual that they are full and to stop eating. Therefore, the end result, is overeating and ultimately weight gain.

Vitamin D Deficiency Causes

Vitamin d deficiency can occur as a result of many reasons. Limited exposure to sunlight leads to vitamin d deficiency. This may result from being homebound, covering your full body, having an occupation inhibiting exposure to sun and living in northern attitudes. Vitamin d deficiency is also caused by lack to consume the right levels of vitamin d over time. This results from being a strict vegetarian, as most sources of vitamin d are animal-based such as fish and beef liver. Having a dark skin is also a cause of vitamin d deficiency. The melanin pigment in dark skins hinders the skin’s effectiveness in making vitamin d from sunlight exposure. Research shows that age also causes vitamin d deficiency. Even when regularly exposed to sunlight, the skin of old adults produces less vitamin D compared to young adults. Being obese also causes vitamin d deficiency as vitamin D is less bio -available to such people therefore making low-level vitamin D to be highly prevalent in them. Having digestive diseases such as celiac disease and Crohn disease also causes vitamin d deficiency. This is because such disease inhibits the ability of the body to absorb vitamin d from food sources.

Normal Vitamin D Levels

The accurate method of measuring Vitamin D is the 25-hydroxyvitamin D blood test. The vitamin d levels are measured as nanograms per milliliter (ng/mL). A level between 20 and 50 ng/ml is usually recommended, although some experts consider the level between 30 and 50 ng/ml as the adequate for healthy people. A level that is less than 12 ng/ml points out vitamin D deficiency.

Vitamin D Benefits

Vitamin D plays a very substantial role in the body and is associated with many benefits. Vitamin D facilitates maintenance of phosphorous levels and regulation of calcium, which helps in maintaining healthy bones. Children given high amounts of vitamin d supplements usually have a reduced risk of flu. Vitamin d also enhances the anti-inflammatory effects of glucocorticoids hence enabling it be used as a therapy for steroid-resistant asthma. Another benefit of vitamin d is that absorbs calcium in the intestines, hence preventing it from being excreted through kidneys. Vitamin d also reduces cancer progression by regulating the growth of new blood vessels in cancerous tissues. Additionally, vitamin d is beneficial in that helps protect various diseases such as type 1 diabetes. Vitamin d also supports lung functioning. 

Vitamin D Dosage

Recommended Dietary Allowances (RDAs) for Vitamin D

Recommended Dietary Allowances (RDAs) for Vitamin D

To determine the dosage of vitamin d, it can be measured in two ways. First, is it can be measured in micrograms (mcg), and secondly in International Units (IU). During conversion, 1 mcg of vitamin D is equal to 40 IU of vitamin D. According to the US Institutes of Medicine (IOM), the dosage of vitamin d should be:

Infants 0-12 months – 400 IU (10 mcg)

Children 1-18 years – 600 IU (15 mcg)

Adults to age 70 – 600 IU (15 mcg)

Adults over 70 – 800 IU (20 mcg)

Pregnant or lactating women – 600 IU (15 mcg)

Natural Food Sources of Vitamin D

The most common and freely available source of vitamin D is the sun. The sun is also considered as the most efficient source of vitamin d. Foods are also sources of vitamin D. This list shows the richest natural food sources of vitamin d and their levels (NIH Office of Dietary Supplements).

Cod liver oil, 1 tablespoon: 1,360 IU

Herring, fresh, raw, 4 ounces: 1,056 IU

Swordfish, cooked, 4 ounces: 941 IU

Raw maltase mushrooms, 1 cup: 786 IU

Salmon, sockeye, cooked, 4 ounces: 596 IU

Vitamin D from Sun Exposure

Most people meet at least some of their vitamin D needs through exposure to sunlight. Ultraviolet (UV) B radiation with a wavelength of 290–320 nanometers penetrates uncovered skin and converts cutaneous 7-dehydrocholesterol to previtamin D3, which in turn becomes vitamin D3. Season, time of day, length of day, cloud cover, smog, skin melanin content, and sunscreen are among the factors that affect UV radiation exposure and vitamin D synthesis.

Vitamin D Deficiency Treatment

The standard vitamin D deficiency treatment is supplementation. Eating the right foods may take long to recover from the deficiency as the level of vitamin d is usually very low in foods. Therefore, supplementation, especially with vitamin D3 should be considered. Regular exposure to sunlight can also serve as a treatment. Foods with high levels of vitamin d should be consumed constantly.



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