Last updated 15:56, Wednesday, 14 May 2008

WITH the summer holiday season coming up, many of us will be embarking on a fitness regime to tone up and loose a bit of weight, but how many of us have broken it within days?

Similarly some of us manage to persevere only to put the weight we have lost back on if not more within no time at all. So why does this happen?

Carbohydrates, our body’s main energy source, are found in starchy foods such as bread, pasta, gains and potatoes as well as sugary foods such as cakes, biscuits and honey.

All carbohydrates have the ability to raise blood sugar levels and the rate that this happens is measured on the glycaemic index (GI).

When blood sugar is raised, the pancreas releases insulin to control these levels. Insulin then stimulates the release of lipoprotein lipase, an enzyme which encourages the extra glucose (sugar) to be stored as fat. A diet containing many high GI foods will have sharply fluctuating blood sugar levels, and high insulin secretion which encourages fat storage. Not only this, but a high GI diet will also leave you feeling lethargic, hungry and craving another glucose hit.

The simple rule to losing weight is to follow a healthy diet to regulate your blood sugar and to participate in regular, varied exercise. The main points are:

Meals need to be eaten regularly and on time to avoid going into a blood sugar low and to keep energy levels up. Try not to skip breakfast, as this is the most important meal of the day.

Eat foods which release their fuel slowly – these are principally fibre-rich carbohydrates such as fruit, vegetables, pulses, legumes and some grains such as rye and barley – along with proteins like grilled chicken and fish.

Avoid eating refined carbohydrates, processed foods, caffeine and other stimulants.

For more information on healthy eating and diet tips, visit www.5aday.nhs.uk.