Welma Stonehouse: The importance of folate

Folate is essential for synthesis of DNA and is therefore required for all rapidly growing cells. Without folate living cells can’t divide and new cells can’t be made.

“Therefore the need for folate is increased during situations when cell multiplication is needed such as pregnancy or any situation where cells are damaged and need to be replaced. Another key role of folate in the body is to break down homocysteine, an amino acid associated with heart disease.

“Thus, folate is important for every one. Folate deficiency can result in a type of anaemia (megaloblastic anaemia), lower cognitive ability, weakness, fatigue, irritability, depression, elevated homocysteine levels and neural tube defects. It is recommended that adults consume 400µg of folate from food each day.

“However, women and men in New Zealand only consume about 220 and 286 µg, respectively, of folate per day which is well below the recommended intake level. Main food sources of folate are green leafy vegetables (broccoli, spinach, salad greens), legumes and fortified grains.

“It is important to realise that folate in food is easily destroyed by cooking. Folic acid found in fortified foods is much better absorbed than folate in food and is therefore an important source of folate in the New Zealand diet.

“Scientific evidence has shown that 400µg/day of folic acid from supplements or fortified foods in addition to normal dietary folate greatly decrease the risk of neural tube defects. Because 50% of pregnancies are unplanned and because neural tube defects occur early in development before most women even realise that they are pregnant it is extremely important that women of child bearing age consume higher amounts of folate or folic acid.

“Voluntary fortification of foods with folic acid will be ongoing and provides women with an effective means of increasing the intake of folic acid; however folic acid supplements will be required to reach optimal levels.”

Dr Welma Stonehouse is Associate Professor in Human Nutrition at the Institute of Food, Nutrition and Human Health at Massey University.