By June Cheong

Wholegrains possess all three parts of the grain: the fibre-rich outer layer known as the bran; the central starchy part known as the endosperm; and the nutrient-packed inner area known as the germ.

The bran is rich in fibre, B vitamins and minerals like zinc, iron, magnesium and potassium.

The germ is packed with vitamin E, B vitamins, polyunsaturated fats, trace minerals and phytochemicals while the endosperm contains mainly carbohydrate and protein.

"When wholegrains are refined or undergo a milling process, the bran and germ are removed, reducing the grain's nutritional value.

"You can fortify it by adding vitamins and minerals but you can never put the fibre back," said Ms Jaclyn Reutens, a dietitian at Aptima Nutrition & Sports Consultants.

Common wholegrain types are wholewheat, oatmeal, wholegrain barley, wholegrain corn (popcorn), brown rice, red rice, rye, buckwheat, bulgur, quinoa and millet.

When the label says wholemeal, this refers to wholegrains that have been milled to a finer texture but still have the three layers of bran, endosperm and germ intact.

This article was first published in Mind Your Body, The Straits Times.