As mentioned, vitamin D is called the “sunshine” vitamin as our body can make this vitamin once exposed to sunlight. The sun is the best source of vitamin D, but how much you get from sunlight depends on the geographical location, exposure to the sun, skin colour, weather and sunscreen.

Vitamin D is firmly called one of the 4 fat-soluble vitamins, technically it’s not a vitamin. Although it is only required in minuscule amounts by the body, it breaks the rules of vitamins as its produced by the human body and is absent from natural sources of food except for egg yolks and fish. Having said this, it must be transformed by the body before it does any good. Moreover, although it’s required in small amounts, it’s essential for health.

Low levels of vitamin D are associated with serious health consequences:

Osteoporosis

Depression

Muscle weakness

Why is Vitamin D important?

Vitamin D is primarily an essential nutrient that our body needs to build strong bones. This is done by helping our body in absorbing and maintain adequate levels of two other important nutrients namely calcium and phosphate by instructing the cells in the gut to absorb them to build strong bones and teeth.

Sources of Vitamin D

Sunlight

Food and

Supplements

Sunlight

Vitamin D is unique in the sense that it can be made once our body is exposed to sunlight. When ultraviolet light from the sun, hits the skin, particularly mid-day, triggers the production of vitamin D. When one is exposed to sunlight,7- dehydroxycholesterol in the skin absorbs the ultraviolet B radiation which produces the pre-vitamin D3 and this later isomerizes to Vitamin D3. However, exposure to the sun for too long can also cause cancer.

Midday is the best time especially when the UV B radiation is intense to produce Vitamin D and the body can manufacture it efficiently during this period, within 13 to 15 minutes of exposure.

Again other factors may interfere with the absorption of Vitamin D which could be due to:

Skin colour

People with darker skin, having more melanin pigment may need longer exposure to sunlight to manufacture Vitamin D as the melanin pigment help protects the skin against damage from sunlight.

Sunscreen

The use of sunscreen to protect skin from sunburn and skin cancer contains chemicals that will either reflect, absorb or scatter sunlight, whereby the skin is exposed to lower levels of UV rays. Some studies do mention that although sunscreen is used, being exposed long enough to sunlight can still produce Vitamin D and it is still inconclusive due to the short period of study.

Other factors are the time of the day, season, limited outdoor time, the amount of skin exposed to sunlight and age where lesser Vitamin D is made as you grow older.

Food sources

There are limited food sources of vitamin D and it is due to this that there are beverages and food fortified with vitamin D that should be noted on the nutrition label. Besides this other food sources are egg yolk and fatty fish like salmon, trout, tuna and sardine.

Supplements

Vitamin D-rich foods and supplements are important, especially for people who find it difficult to be exposed to the sun. But if you fall into a risk category, it’s best to talk to a medical practitioner about taking supplements and usually 600 international units a day will quickly correct the deficiency. However, most of us are found to have adequate Vitamin D in us.

A word of caution

However, it must be noted that taking too much vitamin D is also harmful as it may overly increase the absorption of calcium causing health problems like kidney stones and damaging the heart and blood vessels. Again having natural sources of Vitamin D through food sources are much safer and adequate exposure to sunlight ( 15 to 20 min) will be the best way to get your vitamin D.

Summary

A short burst of sun exposure is the best source of Vitamin D, but caution must be taken to ensure that it is not for too long as it can cause sunburn and skin cancer too. If you plan to stay longer in the sun, sunscreen is suggested after 30 minutes of exposure to the sun with no protection. For those living far away from the equator, longer exposure to the sun may be needed as the UV B radiation are weaker in these areas and for those who are unable to have sunlight, Vitamin D-rich foods or supplements are suggested.