Vitamin Expert
A selection of dairy products

Vitamin D

Vitamin name
Vitamin D
What’s it used for? Regulating calcium absorption; healthy bones and teeth; immunity; muscle function; childhood growth
Best food sources Animal sources such as egg yolks, dairy products, liver, oily fish and fortified margarine
How much do I need? NRV is 5 ug per day*
Need to know The best source of vitamin D is from the sun!

*A Nutrient Reference Value or NRV is the recommended level set by the UK Department of Health for daily nutrient intake

Vitamin D

Vitamin D is known as the ‘sunshine vitamin’ because it’s predominantly produced on the skin in the presence of sunlight. It’s this action that causes many people to describe it as both a vitamin and a hormone.

Living in the northern hemisphere is a risk factor for deficiency, particularly during the winter months. Such is the concern that the UK Department of Health recommends taking a supplement of 10 ug per day – twice the recommended NRV – to ensure adequate levels. This is particularly important for at-risk groups such as pregnant and breastfeeding women, the elderly, children up the age of 5 years and those with darker skin tones. However, it’s sensible for everyone to supplement during winter.

Vitamin D is also known as calciferol, which actually refers to several fat-soluble vitamins. Vitamin D2 is the most used synthetic form, with vitamin D3 being the better absorbed and natural form, found in animals. Both are converted in the liver and kidneys to the active form of Vitamin D.

Why do I need it?

Vitamin D is famous for its role in bone health. It’s essential for proper calcium metabolism, ensuring there is sufficient in the bones and teeth. So important is this function that even if calcium intake and body stores are sufficient, if vitamin D is low there is still a risk of poor calcification of the bones. Vitamin D is therefore absolutely essential for healthy bones and teeth in growing children.

Vitamin D also works with parathyroid hormone in calcium metabolism. This helps regulate the amount of calcium and phosphorus in the blood; if blood levels are low, these minerals are pulled from the bones causing various serious bone diseases.

Vitamin D plays a major role in immune function by increasing activity of the body’s natural killer cells thereby fighting possible infections. Vitamin D also plays a key role in normal blood clotting and heart function, muscle growth and prevention of type 2 diabetes.

Vitamin D is a fat-soluble vitamin that is stored in the liver, skin, brain, spleen and bones, although deficiency is still widespread across all age groups.

Best food sources

Good natural food sources of vitamin D include cod liver oil, cold water fish (mackerel, salmon, herring) egg yolks and butter.

Foods high in Vitamin D

fish oil
Fish oil – 250 ug per 100g
Mackerel – 11.8 ug per 100g
Salmon – 8.2 ug per 100g
Sardines – 5.3 ug per 100g
boiled eggs
Eggs – 2.3 ug per 100g

Are you getting enough?

Vitamin D’s primary function is in the prevention of diseases associated with the bones. It is therefore crucial in preventing the childhood deficiency disease called rickets which causes the tell-tale bow legs. This disease had almost been eradicated but has started to re-emerge in more recent times in countries in the northern hemisphere, purely down to vitamin D deficiency.

Long term deficiency of vitamin D may also result in osteoporosis, another serious bone disease. Gum disease and tooth decay can also be a sign of deficiency.

Did you know?

Vitamin D is safe to take during pregnancy and breastfeeding and is recommended to supplement at 10 µg daily throughout this period – consult your healthcare professional for advice
Vitamin D supplementation has been found to be effective in cases of multiple sclerosis which is also becoming more prevalent in northern Europe
Muscle weakness may also be a sign of vitamin D deficiency

For all the latest research on vitamin D click here

Try this

Vitamin D is found in the Alive! range of multi vitamins and minerals.

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