KNOW YOUR VITAMIN: VITAMIN D – THE SUNSHINE VITAMIN

Vitamin D is a fat-soluble vitamin stored in the body’s fatty tissue and liver. It helps your body absorb calcium, which is essential for building strong bones. Together with calcium, vitamin D helps protect against osteoporosis and rickets. It also supports nerve signaling, muscle contractions, and the immune system.

How Much Vitamin D Do You Need?

According to ICMR 2021 recommendations:

How to Get Vitamin D?

Very few foods naturally contain vitamin D.

Natural Sources of Vitamin D:

• Fatty fish (e.g., salmon, mackerel, sardines)
• Fish liver oils
• Beef liver
• Egg yolks
• Cheese
• Mushrooms (in small amounts)

Sunlight Exposure:

• Vitamin D production in the skin is the primary natural source of vitamin D. Our body makes Vitamin D when the bare skin on our face, hands, legs (without sun screen) are exposed to Ultraviolet-B rays from sunlight.
• Aim for 10 to 15 minutes of sunlight on the face, hands, and legs, without sunscreen, several times a week.
• Note: Sun exposure through windows does not produce vitamin D.

However, the amount of vitamin D produced by sunlight exposure can vary greatly from person to person. People who do not live in sunny places may not make enough vitamin D within a limited time in the sun. Cloudy days, shade, and having dark-coloured skin also cut down on the amount of vitamin D the skin makes. Also, skin does not make vitamin D from sunlight through a glass window. Sun’s rays in a sunny office or driving in a car unfortunately won’t help to obtain vitamin D as window glass completely blocks UVB ultraviolet light.

Vitamin D Deficiency

Obtaining sufficient vitamin D from natural (non-fortified) food sources alone is difficult. For many people, consuming vitamin D-fortified foods and exposing themselves to sunlight are essential for maintaining a healthy vitamin D status. However, the following groups are among those most likely to have inadequate vitamin D status and may need supplement.

Risk Groups:

• Older adults: Reduced ability to produce vitamin D.
• Breastfed infants: Require a supplement of 400 IU/day.
• People with limited sun exposure: Those who stay indoors or cover their skin.
• People with dark skin: Lower vitamin D production due to melanin.
• Dietary restrictions: Those avoiding dairy, eggs, or fish.
• Health conditions: Liver diseases, cystic fibrosis, Crohn’s disease.
• Obesity and gastric bypass patients: Increased risk of deficiency.

Symptoms and Risks of Vitamin D Deficiency

• Children: Risk of rickets, causing soft, weak bones.
• Teens and adults: Risk of osteomalacia, leading to bone pain and muscle weakness.

Supplementing Vitamin D

• Supplements are available in various forms like tablets, capsules, gummies, liquid drops. Sometimes they are also added to fortify foods like biscuits, drinks.
• The two forms of vitamin D in supplements are D2 (ergocalciferol) and D3 (cholecalciferol). Both forms increase vitamin D in your blood, but D3 might raise it higher and for longer than D2.
• Because vitamin D is fat-soluble, it is best absorbed when taken with a meal or snack that includes some fat.

Vitamin D Toxicity

High levels of vitamin D are almost always caused by consuming excessive amounts of vitamin D from dietary supplements not by normal diet or sun exposure.

Symptoms of toxicity:

• Symptoms include nausea, vomiting, weakness, frequent urination, and hypercalcemia (high blood calcium levels).
• Severe cases can lead to bone pain, kidney problems, and heart issues.
• Doses higher than the RDA are sometimes used to treat medical problems such as severe vitamin D deficiency, but these are given only under the care of a doctor for a specified time frame.

Prevention:

• Stick to the recommended daily allowance.
• Always consult with your healthcare provider before taking supplements.

Drug Interactions

Vitamin D supplements can interact with certain medications, such as:

• Orlistat (weight loss drug)
• Statins (cholesterol-lowering drugs)
• Thiazide diuretics (blood pressure medications)
• Steroids

If you are on prescription medicine and planning to take Vitamin D supplements, please check with your physician before taking supplement.

Vitamin D and COVID-19

The rationale for using vitamin D was based largely on immunomodulatory effects that could potentially protect against COVID-19 infection or decrease the severity of illness. Based on the available clinical studies, there is insufficient evidence to recommend either for or against the use of vitamin D for the prevention or treatment of COVID-19. Hence it is not advisable to consume higher doses of Vitamin D3 for covid-19.