Bariatric surgery is booming. The number of interventions continues to grow: it has tripled over the past seven years to reach 43,000 operations per year in France .

According to the Haute Autorité de Santé (HAS), this surgery is for people with severe or massive obesity , that is to say, whose Body Mass Index (BMI) is greater than 35 or 40 *. If the results in terms of slimming are spectacular, other benefits are also expected. Hence its new name: the experts do not speak more about bariatric surgery, but about metabolic surgery.

A liver in better condition

When the liver is overloaded with fat, bariatric surgery prevents it from degenerating. "Very recent studies in Lille have shown that 85% of patients with fatty liver (liver too fat) found a normal liver after a bypass - short circuit between the upper stomach and the small intestine - or a sleeve - narrowing of the stomach-, "says Professor Lawrence Serfaty, a hepatologist at Saint-Antoine Hospital in Paris.

On the occasion of the last NASH Congress ** held at the Institut Pasteur, other benefits were disclosed. " Bariatric surgery also causes a strong regression of cirrhosis and liver fibrosis , likely to evolve into cancer of the liver," says Professor Philippe Mathurin, hepatologist at Lille University Hospital.
To verify this turnaround, a new study will be launched end of 2017 on patients not necessarily obese but suffering from a very important liver fibrosis.

Diabetes improved

Bariatric surgery is also a remarkable treatment for type 2 diabetes . "About 80% of diabetics no longer have diabetes after intestinal surgery for obesity," says Serfaty. This benefit is not only obtained in patients who required a high weight reduction, but also in those without significant overweight.

Moreover, in case of obesity, the improvement in blood sugar (blood sugar) occurs very quickly after the intervention, well before the loss of weight is significant.
This phenomenon is explained by dietary restriction following surgery and changes in the secretion of digestive hormones (ghrelin, peptide YY ...) involved in the regulation of glucose levels, as shown by a study conducted by the Institute. Baker Research Center (Australia).

The heart and the kidneys better protected

Sleeve, bypass or gastric band also protect the heart as they regulate blood lipid levels and reduce hypertension (from 14-9 to 12-7), two important risk factors for myocardial infarction .

One year after surgery, 91% of patients no longer have excess triglycerides and nearly 60% have normal blood pressure. Researchers at Imperial College London have just shown that these interventions also cause a remodeling of the heart muscle, including a reduction in the volume of the left ventricle, predictive of better cardiovascular health.

Similarly, the functioning of their kidneys has improved. Five years after surgery, only 4 out of 461 patients had kidney failure.

* BMI is calculated by dividing weight by height squared (Kg / m ² ).
** Non-Alcoholic Hepatic Steatosis