It's often said that breakfast is the most important meal of the day. The morning meal provides solid fuel with which the body can re-ignite its energies after the lengthy overnight fast. Breakfast eating is associated with improved scholastic performance in children, and seems to boost brain power for adults, too. Studies also show that early-in-the-day eating helps to reduce our overall intake of food - something that has the potential to keep our weight and waistlines in check. It seems there is genuinely good reason for viewing the first meal of the day as second to none.

For many of us and our children, standard breakfast fare means a bowlful of cereal. Quite rightly, the sugar-saturated varieties do not enjoy the healthiest of reputations. Most of us will therefore be more comfortable stoking up on drabber, less-sugared brands, content in the knowledge that their substantially starchy nature will deliver us with a sustained release of sugar.

However, even cereals spared sugar-encrustation can cause undesirable upset in the body's sugar levels. The speed and extent to which a food releases sugar into the bloodstream is quantified by its glycaemic index (GI). Top slot in the GI chart goes to the rapidly releasing sugar glucose, with a value of 100. Even without a sprinkling of sugar on top, many commonly eaten cereals have GIs not far off this. Cornflakes, for instance, have a GI of about 80. One wheat-based cereal that boasts no added sugar at all has a GI of this order too.

A likely consequence of the extremes of blood sugar cereals tend to induce is the secretion of considerable quantities of the hormone insulin. While insulin is essential to prevent sugar levels rising to undesirable levels, it also stimulates the manufacture of fat in the liver and reduces the body's ability to burn fat as a fuel. Insulin in excess is also believed to increase the risk of type 2 diabetes and heart disease.

Fortunately, not all grains have the same capacity to upset blood sugar and insulin balance. The pick of the crop is oats. Rolled oats can be used to make porridge (with a GI in the 50s), or form the base ingredient in a nutritious muesli. To improve their digestibility, I suggest soaking them overnight in water or milk. Ingredients that will add to their palatability and nutritional attributes include yogurt, raw nuts and/or seeds, and fresh and/or dried fruit.

Another benefit of such a concoction is its much lower content of salt compared to the majority of commercially available cereals. Cornflakes, for example, generally have a saltiness equivalent to that of sea water. Through its potential to push up blood pressure, a surfeit of salt is believed to increase the risk of heart attacks and strokes.

The ability of much traditional breakfast fare to induce undesirable upset in the body's biochemistry and physiology might cause some to brand it a cereal killer.