The fructose factor

Fresh fruit is a wonderful food and, when you consume the fruit sugar fructose in this form, then the other nutrients and fibre in the fruit ward off any negative effects of the fructose. The problem comes when you isolate fructose into high fructose corn syrup or other synthesised forms that are used in many processed foods. Despite their similar chemistry, fructose and glucose affect the body in quite different ways and this new study has shown some of the specific problems with fructose.

The study involved healthy young men being given either glucose, fructose or a placebo via a feeding tube. The subjects were then asked how satiated they felt, blood samples were taken to measure satiety hormones and MRI scans were used to measure brain activity.

The results showed that after eating fructose, the subjects felt less satiety, there was minimal effect on satiety hormones in response to fructose, and the MRI scans showed that different areas of the hippocampus and amygdala were stimulated by fructose in comparison to glucose. The net result is that fructose results in feeling less “full” and less rewarded so you will still want more food after consuming fructose-sweetened foods, which is why it may be being implicated in conditions like obesity and diabetes.

As we started out by saying, this does not mean fruit should be tossed out of the diet. What it does mean is that we really need to think about reducing the use of fructose-based sweeteners in processed food and even cutting down on fruit juice consumption. Alternatively, you could eat whole foods that aren’t processed and remove the worry as to what is “sweetening” them. Now that’s a sweet thought.