Do you remember making craft glue out of white flour and water at school? Remember how it set like cement when you used it? And how bad it smelled after sitting on the desk for a few hours? Well, every time you eat white breads, pasta and rice, they turn into craft glue in your stomach, becoming foul, sticking to the walls of your bowel and sucking the life out of you. I call it 'bum glue' and it's just as charming as it sounds.

Refined and processed grains are high in phosphorous, which is acid forming, and when consumed as flour causes problems in the brain, the joint capsules and the gut (bloating). They are also rich in phytates, which are the acids that bind minerals to the intestinal tract causing them to be excreted unused. So what may seem like a 'healthy' meat and salad sandwich on white bread for lunch every day will actually leach the water-soluble nutrients out of your body.

Unlike highly processed white foods, wholegrain foods contain all the components of the grain, including the germ (which is where most of the nutrients live), the bran and the endosperm. Typical wholegrain foods include wholemeal breads, multigrain breads (although watch these as the grains are often still in a white bum glue base), rolled oats, wholemeal pastas and brown rice.

Wholegrain is the closest to nature, meaning it contains all of the components of the grain and can be whole, cracked or milled. Wholemeal contains grains that have been milled to a finer texture, but it retains all the components of the grain, so it is still wholegrain. Wholemeal and rye breads are the ones you would think of in this class (just watch them though as light rye breads are generally cut with white bum glue flour).

Wholemeal and wholegrain breads are naturally high in fibre. White high fibre breads have had fibre added, but they are still white and do not always contain the outer layers of the grain, so I still class them as bum glue.

So, why go brown?
For a start, the outer layers of grains are particularly rich in fibre, which helps to remove toxins, promote healthy gut bacteria and keep you regular. They also contain vital vitamins, minerals and other nutrients. Wholegrains are essential in keeping the cells of your bowel walls healthy and studies have shown that people who eat wholegrain foods regularly are less likely to develop bowel cancer.

Then there's the added energy that brown grains can give you. Have you ever noticed that an hour or so after lunch you are ready for a nap or a trip to the vending machine?

If you eat that 'healthy' salad and meat sandwich on white bum glue bread for lunch, chances are that an hour later you'll be ready for a nap, chocolate or coffee - it's the mid-afternoon slump that we know so well. Depending on the Glycaemic Index (GI) of the food you've eaten and the level of chromium in your body, your blood sugar can start going up and down like a roller-coaster, taking your moods, emotions and energy levels along for the ride. This is because the white bread is a high GI food, and it causes your insulin levels to spike and your body to overreact, draining your energy and leaving you feeling tired and lethargic. The trick is to remove the refined grain so that the overreaction doesn't happen - simply switching to brown bread is a good start.

The Glycaemic Index is a method of classifying the glycaemic (blood sugar) response to carbohydrate-rich foods. High GI foods enter your blood stream faster giving you that sugar hit, while low GI foods enter more slowly and raise energy levels without the sugar spike. In years gone by we used to call high GI foods 'simple' carbohydrates and low GI foods 'complex' carbohydrates. As human beings we require a balance of both in our diets. You can reduce the glycaemic impact of high GI foods by combining them with good fats or high quality proteins, both of which have low glycaemic indexes.

If you did nothing other than replace white bum glue grains for brown in your diet, your basic level of health would increase dramatically. Just remember to avoid the bum glue - eat unrefined brown grains (brown rice, pasta and breads) - and go for low GI.