Inspired living

Watermelon weighs in


Despite all the individual differences that exist between us there are some universal commonalities. One of these connecting concerns is that everyone wants to keep their weight at healthy levels. We also are united in wanting to keep a healthy heart that will keep pumping for us as long as possible. Now it seems that a pleasurable activity like eating watermelon might help you to achieve both of these universal aims.

For their study, researchers divided their mice into two groups. Both groups of mice were given a diet high in saturated fat and cholesterol. One group was given water that consisted of two per cent watermelon juice while the other group was given water without watermelon but with exactly the same carbohydrate content.

The mice given watermelon juice showed 50 per cent less plaque in their arteries than the other group and gained 30 per cent less weight than the control group. The researchers say that they believe it is the ingredient citrulline from watermelon that is probably responsible for these effects.

The sweetness of watermelon may make it seem an unlikely candidate for weight loss, especially when it has a high glycaemic index (GI). However, glycaemic load (GL) may explain the effect.

The glycaemic index of food is a ranking of foods based on their immediate effect on blood glucose (blood sugar) levels and thus the production of insulin. All foods are ranked according to how quickly they will cause a rise in blood sugar compared to simple glucose. Foods that break down quickly during digestion have the highest glycaemic indexes causing blood sugar and insulin to rise fast and high. Carbohydrates that break down slowly, releasing glucose gradually into the blood stream, have a low glycemic indexes. The lower the glycaemic index, the less likely that food is going to contribute to the production of fat. However, while the glycaemic index of food is important, the glycaemic load may be even moreso.

The GL takes into account both the GI of a food and also it\’s carbohydrate content, thereby giving a fuller picture of the effect of that food on blood glucose levels. The GL tends to be higher for those foods which provide the most carbohydrate. While the GI of watermelon may be high at 72, it\’s GL is low at 4 because of its low overall carbohydrate content.

It seems then that as a source of citrulline, and also the antioxidant lycopene, watermelon may be a healthy food option this coming summer. When you consider that an estimated 20 per cent of the watermelon crop is wasted each year because it does not look appealing, it also points to some health promoting uses that could employ that less glamorous part of the crop, at once helping the health of society and preserving resources.


Terry Robson

Terry Robson is the Editor-in-Chief of WellBeing and the Editor of EatWell.