What is vitamin D

What is Vitamin D

Vitamin D or vitamin D is one of the fat-soluble vitamins and is also called the sunshine vitamin, because the body manufactures it when exposed to ultraviolet rays of the sun, and sunlight is the most important factor in the manufacture of vitamin D in the body through the skin. We will learn about the types of vitamin D, its sources, appropriate doses, and the normal rate of vitamin D in the body. [1]

Contents

Types of Vitamin D

Sources of Vitamin D

The best time to take Vitamin D is from the sun

Benefits of Vitamin D

Vitamin D dose

Daily vitamin D dose

Weekly vitamin D dose

Increase vitamin D in the body

Vitamin D analysis and the normal range of vitamin D

Types of Vitamin D

There are two main types of vitamin D: [1]

Vitamin D2 (ergocalciferol): Found in some plant sources.

Vitamin D3 (cholecalciferol): found in animal sources.

It is often recommended when choosing vitamin D supplements to choose the types that contain cholecalciferol or vitamin D3, as the metabolism that takes place in the liver differs for both vitamin D2 and D3, and it is likely that vitamin D3 will be more effective compared to vitamin D2, as it is the natural form that is made in the body when sun exposure

For more: What are the types of vitamin D?

Sources of Vitamin D

There are many sources of vitamin D between natural and unnatural sources, and it is preferable to obtain it from its natural sources, so where is vitamin D? [1,2,3,4]

The following are the most important sources of vitamin D:

The sun: The sun is the main source of vitamin D, as adequate exposure to it daily for at least 15 minutes contributes to stimulating the production of vitamin D3 (cholecalciferol) in the skin under the influence of ultraviolet radiation, while vitamin D2 (ergocalciferol) is produced in plants and is found in foods. Fortified with vitamin D.

Also read: Do sunscreens deprive us of vitamin D?

Foods containing vitamin D: The body can manufacture sufficient amounts of vitamin D, but a person may not get enough of it if he is not sufficiently exposed to sunlight, or if the body is having difficulty absorbing vitamin D, all of which lead to Deficiency in it, and the emergence of symptoms that ensue.

Therefore, the body can obtain vitamin D from some foods, the most important of which are:

Fatty fish: Fatty fish is a good source of vitamin D, such as salmon, which contains 100 grams of about 526 international units of vitamin D. Other examples of fish that contain vitamin D in good quantities are trout, mackerel, tuna, and eel.

Canned tuna: Fresh fish is not the only way to get vitamin D, as vitamin D is also found in canned tuna and sardines, as 100 grams of canned light tuna contains 268 international units of vitamin D, while 100 grams of canned sardines contain 193 international units.

Certain types of mushrooms: Mushrooms have the ability to produce vitamin D when exposed to ultraviolet light, but there are types that are grown in the dark, and therefore do not contain vitamin D. However, some specific brands grow mushrooms under ultraviolet light to stimulate the production of vitamin D.

Fortified milk: Milk does not naturally contain vitamin D, but most brands sold in the market are fortified with it. It also sometimes supports soy and rice milk to compensate for the lack of vitamin D in them.

Some types of orange juice: Some types of orange juice are fortified with vitamin D, and usually one cup of fortified orange juice contains about 100 international units of vitamin D, but the amount varies according to the brand.

Egg yolk: One of the sources of vitamin D is also the egg yolk, so it is important to eat whole eggs and not just the whites, as one egg yolk contains about 37 international units of vitamin D, but it is not recommended to try to get the body’s daily need of the vitamin only from eggs.

Fortified cereals: There are some types of low-calorie cereals fortified with vitamin D that help the body get part of its daily need of the vitamin and prevent its deficiency. These pills can be taken with fortified milk, as milk also contains calcium.

Beef liver: Beef liver contains many nutrients, and one serving of cooked beef liver contains about 50 international units of vitamin D, in addition to vitamin A and iron.

Cod liver oil: One tablespoon of cod liver oil contains about 1,300 international units of vitamin D, more than double the daily need (600 international units per day).

Ultraviolet lamps: People who are at risk of developing a vitamin D deficiency or who have symptoms of a vitamin D deficiency due to poor absorption of vitamin D may consider exposure to ultraviolet-emitting lamps.

But these lamps have risks, such as skin diseases and skin cancer, and they also need protective glasses, so it is not preferable to use this method except with a doctor’s recommendation.

Dietary supplements: Vitamin D supplements are available in the form of oral drops, syrup, vitamin D pills, and needles for injection into the muscle.

The best time to take Vitamin D is from the sun

The best time to take vitamin D from the sun is during the middle of the day when the sun's rays are vertical or near vertical. Factors affecting the efficiency of vitamin D intake from the sun include: [3]

Sun exposure time.

Area of skin exposed to sunlight.

Skin colour, as the darker the skin, the slower it is to synthesize Vitamin D.

As for vitamin D pills, the best time to take them is after eating a main meal, as vitamin D is a fat-soluble vitamin, which means that it is better absorbed into the bloodstream when taken with or after foods rich in fats, such as avocados, nuts, full-fat dairy products, and eggs.

Benefits of Vitamin D

Vitamin D is one of the most important vitamins involved in the bone-building metabolism process, by facilitating the intestinal absorption of calcium, and vitamin D also contributes to the transfer of calcium from the intestine to the blood by proteins called calbindin (in English: Calbindin). It also stimulates the absorption of magnesium and phosphate.

In addition, vitamin D regulates the levels of calcium and phosphorus in the blood; Bones help increase calcium absorption, thus enhancing bone strength and density, preventing osteoporosis, thinning, and rickets. It should be noted that vitamin D prevents calcium deficiency and bone problems in patients with kidney failure.

Other important vitamin D benefits include: [5,6]

Reducing digestive disorders, especially Irritable Bowel Syndrome.

Prevention of multiple sclerosis, as adequate levels of vitamin D in the blood contribute to the prevention of this disease.

Regulate insulin levels in the body, and reduce the risk of type 1 diabetes.

Increased chances of pregnancy after insemination or artificial fertilization in women who do not suffer from vitamin D deficiency compared to those who suffer from its deficiency.

Enhancing fertility in men by improving testosterone levels, as well as improving semen quality.

Preserving the safety of the pregnant mother and fetus, avoiding premature birth, and preventing fetal bone deformation.

Contribute to the growth of children's bones and prevent rickets. It is recommended to give vitamin D supplements to infants from birth under the supervision of a doctor. Since mother's milk does not provide them with an adequate amount of it.

Strengthening immunity, protecting against cancer and chronic diseases, especially in the elderly. Vitamin D also reduces the risk of immune diseases, and its deficiency is associated with an increased risk of autoimmune diseases and exposure to various diseases.

Reducing the symptoms of premenstrual syndrome with calcium supplements, as vitamin D helps reduce the excess production of hormone-like substances called prostaglandins, which cause pain associated with menstruation, which contributes to reducing this pain.

Stimulating old hair follicles, increasing and stimulating the formation of new hair follicles, and it is also believed that there is a relationship between alopecia and vitamin D deficiency.

Also read:

The benefits of vitamin D for physical and psychological health

Does vitamin D deficiency cause hair loss?

Vitamin D dose

The recommended preventive doses of vitamin D are given in the form of a daily dose or a weekly dose, and it can be obtained from natural sources or nutritional supplements. The recommended vitamin D dose is as follows:

Daily vitamin D dose

The recommended daily needs of vitamin D vary according to the age group, as follows: [7]

The daily dose of vitamin D for infants from birth to one year of age: a daily dose of 400 international units, taken in the form of oral drops.

The daily dose of vitamin D for children after one year until the age of 18 years: 600 international units per day.

The daily vitamin D dose for adults aged 19-71 years: 600 IU daily.

The daily dose of vitamin D for the elderly over the age of 71 years: 800 international units per day.

Vitamin D dose for pregnant women: 1000-4000 IU daily. It should be noted that pregnancy vitamins contain vitamin D, but at a dose of 400 international units only, which is an insufficient amount.

Daily vitamin D dose

The recommended daily needs of vitamin D vary according to the age group, as follows: [7]

The daily dose of vitamin D for infants from birth to one year of age: a daily dose of 400 international units, taken in the form of oral drops.

The daily dose of vitamin D for children after one year until the age of 18 years: 600 international units per day.

The daily vitamin D dose for adults aged 19-71 years: 600 IU daily.

The daily dose of vitamin D for the elderly over the age of 71 years: 800 international units per day.

Vitamin D dose for pregnant women: 1000-4000 IU daily. It should be noted that pregnancy vitamins contain vitamin D, but at a dose of 400 international units only, which is an insufficient amount.

For more:

Vitamin D for pregnant and lactating women

Vitamin D from the first day of birth

Weekly vitamin D dose

Doctors usually recommend that patients with a vitamin D deficiency take a vitamin D supplement of 50,000 IU once a week for two to three months. [7]

Increase vitamin D in the body

Taking vitamin D as a dietary supplement in high doses may lead to high levels of vitamin D in the body and vitamin D toxicity. Although this is rare, it is dangerous, and leads to an increase in calcium in the blood and its accumulation in the body, and the emergence of the following symptoms: [7]

lack of focus

lethargy.

Vertigo.

Depression.

vomiting.

constipation.

Hypertension.

bone loss

Kidney damage.

Vitamin D analysis and the normal range of vitamin D

A vitamin D analysis can be performed in the laboratory to see if its level is in the normal range or not, as the normal range for vitamin D is between 20-50 ng / ml, but if the result is less than 12 ng / ml, a doctor should be consulted to treat vitamin D deficiency.

It is always advised to consult a doctor before starting to take vitamin D supplements to prescribe the appropriate dosage. [7]