Aspartame sugar substitute doesn't help in weight loss; on the contrary, it could be promoting weight gain, reports a recent study.

A team of researchers from Massachusetts General Hospital have found the mechanism behind the aspartame metabolism with the help of a series of experiments.

Health Outcomes Of Aspartame Intake

Richard Hodin, the senior author of study from the MGH Department of Surgery, said that sugar substitutes available in the market are aimed at promoting weight loss and reducing the incidence of metabolic syndrome.

However, a number of studies reported earlier have noted that the sugar substitutes could be doing more harm to body than good, noted the researcher. It is observed in the current study that an enzyme named intestinal alkaline phosphatase (IAP) present in the gut is blocked by aspartame consumption.

As a matter of fact, IAP was previously reported to decrease the incidence of metabolic syndrome and prevent diabetes and obesity. Therefore, it is sensible to assume that aspartame intake may pave way for weight gain and other health problems by blocking IAP, noted Hodin.

In a study published in 2013, Hodin and his team noted that mice that were kept on high-fat diet developed no metabolic syndrome when they were fed with IAP and mice that had developed symptoms already were also found to have improved. The researchers noted that phenylalanine is produced in the body during digestion of aspartame, a compound, which is well known to inhibit IAP.

For the purpose the study, the researchers added IAP to a soft drink containing aspartame and found as a result that the activity of the enzyme was reduced in aspartame-sweetened beverage than in beverage sweetened with sugar.

Aspartame Experiment In Mice

Aspartame was then tested in mice, where one group of mice fed with normal diet and another group of mice fed with high-fat diet were given beverages containing aspartame for a period of 18 weeks. The mice on normal diet took three and a half cans of aspartame-sweetened soft drinks a day and mice on fat-rich diet drank around two cans of soft drink a day.

While mice on normal diet fed with aspartame gained just a little weight when compared to mice on normal diet that had plain water, mice of high-fat diet that drank aspartame beverage gained plenty of weight than their counterparts that had plain water.

Mice on normal as well as fat-rich diet that drank aspartame-sweetened drink had high blood pressure and increased inflammatory protein in blood than their respective counterparts fed on plain water.

Aspartame Sweeteners Don't Work

"People do not really understand why these artificial sweeteners don't work. There has been some evidence that they actually can make you more hungry and may be associated with increased calorie consumption. Our findings regarding aspartame's inhibition of IAP may help explain why the use of aspartame is counterproductive," said Hodin, in a press release.

The study is published in the journal Applied Physiology, Nutrition and Metabolism.

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