Vitamin D

What is Vitamin D? Should pregnant woman take vitamin D supplements?

A vitamin is something that helps our body function – a ‘nutrient’ – that we cannot make in our body.

Vitamin D is known to play an important role in bone metabolism through regulation of calcium and phosphate equilibrium.

Vitamin D is different because even though we call it a vitamin, it is actually a hormone and we can make it in our body.

Our bodies make vitamin D when our skin is exposed to summer sunlight (from late March/early April to the end of September). It's not known exactly how much time is needed in the sun to make enough vitamin D to meet the body's needs but itis also found in food products.

Which foods contain vitamin D?

Vitamin D can be found in the following foods:

· oily fish such as salmon, sardines, pilchards, trout, herring, kippers and eel contain reasonable amounts of vitamin D

· cod liver oil contains a lot of vitamin D (don’t take this if you are pregnant)

· egg yolk, meat, offal and milk contain small amounts but this varies during the seasons

· margarine, some breakfast cereals, infant formula milk and some yoghurts have added or are ‘fortified’ with vitamin D

Why is vitamin D important?

Low vitamin D concentrations are present in a significant proportion of the population. Women with pigmented or covered skin, obesity , immobility and people living in countries with low levels of sunlight are at a higher risk.

A nutritious diet and physical activity will benefit both women and their babies during pregnancy.  While most vitamins and minerals come from our diet, it is common for people in the UK to be low in vitamin D and folic acid, which are important in pregnancy.

During pregnancy, severe maternal vitamin D deficiency has been associated with biochemical evidence of disordered skeletal homeostasis, congenital rickets, and fractures in the newborn.

Infants are born with low vitamin D stores and are dependent on breast milk, sunlight or supplements as sources of vitamin D in the first few months of life. As the vitamin D content of breast milk is dependent on maternal vitamin D status and is often low, and sun exposure may be restricted for infants living at higher latitudes or for cultural or other reasons, infants are particularly vulnerable to vitamin D deficiency. Vitamin D deficiency in infants can lead to bone malformation (rickets),seizures and difficulty breathing.

Vitamin D is added to all infant formula milk, as well as some breakfast cereals, fat spreads and non-dairy milk alternatives. The amounts added to these products can vary and might only be small.  

Vitamin D recommendations

It is recommended that Pregnant and breastfeeding women with dark skin or who get little sun exposure to take a daily dose of 10 micrograms of vitamin D.

Many women may prefer to take a multivitamin tablet throughout their pregnancy, particularly if they find it difficult to ensure a healthy, balanced diet. Multivitamin supplements that are not made specifically for pregnant women are not usually recommended as they may contain high levels of other vitamins, such as vitamin A, which may be harmful to the baby.

Most people aged five years and over in the UK will probably get enough vitamin D from sunlight in the summer, so you might choose not to take a vitamin D supplement during these months. 

You can get vitamin supplements containing vitamin D free of charge if you are pregnant or breastfeeding and qualify for the Healthy Start scheme.