MedDiet Prevents Overeating, Study Finds

A study found ani­mals on the Mediterranean diet (MedDiet) chose not to eat all the food avail­able to them. Consequently, they main­tained a nor­mal weight.

“By com­par­i­son, the ani­mals on a Western diet ate far more than they needed and gained weight,” Carol A Shively, the prin­ci­pal author and a pro­fes­sor of pathol­ogy at Wake Forest School of Medicine, said.

Earlier stud­ies explor­ing the influ­ence of diet on caloric intake have been based largely on two kinds of inves­ti­ga­tions: ani­mal exper­i­ments involv­ing non­hu­man diets and human exper­i­ments involv­ing self-reported dietary infor­ma­tion, which is unre­li­able. The new clin­i­cal trial was the first to com­pare the long-term effects of the MedDiet and Western diet on obe­sity, Shively said.

In the inves­ti­ga­tion, which was pub­lished in the jour­nal Obesity, the sub­jects were non­hu­man pri­mates; and the inter­ven­tion period was 38 months, a time­frame that equates to nine human years. Researchers for­mu­lated the ani­mals’ food to reflect either the MedDiet, where fat and pro­tein are derived mostly from plant sources, or the Western diet, where the nutri­ents come mainly from ani­mal sources. The team per­mit­ted all the ani­mals to eat as much food as they desired.

Results showed that pri­mates on the MedDiet con­sumed less calo­ries, as well as had lower body weight and fat than those on the Western diet, Shively said. Moreover, pri­mates on the Western diet had insulin abnor­mal­i­ties that are indica­tive of a pre-dia­betes state. The find­ings are the first evi­dence that the MedDiet helps pre­vent overeat­ing, obe­sity and pre-dia­betes in com­par­i­son to the Western diet.

Additional find­ings sug­gested the MedDiet is also pro­tec­tive against non-alco­holic fatty liver dis­ease (NAFLD), which can lead to cir­rho­sis of the liver and liver can­cer. Obesity is a pri­mary cause of NAFLD.

“Diet com­po­si­tion is a crit­i­cally impor­tant con­trib­u­tor to the U.S. pub­lic health, and unfor­tu­nately those at the great­est risk for obe­sity and related costly chronic dis­eases also have the poor­est qual­ity diets,” Shively said.

“Eating a Mediterranean diet should allow peo­ple to enjoy their food and not overeat, which is such a prob­lem in this coun­try. We hope our find­ings will encour­age peo­ple to eat health­ier foods that are also enjoy­able, and improve human health,” she added.

In an inter­view with Olive Oil Times, Shively shared her pos­tu­la­tions on why fol­low­ing the MedDiet might lead to less food con­sump­tion.

“I believe that com­po­nents of our Western diet are designed by their man­u­fac­tur­ers to be hyper-palat­able – with a high con­tent of sugar, fat and salt, which we like – so we’ll buy their prod­ucts,” she said. ​“The result is that we eat too much.”

“In con­trast, I think the MedDiet does not have those char­ac­ter­is­tics,” she added. ​“Please note, though, that this the­ory remains a hypoth­e­sis that is yet to be tested. That said, I think the MedDiet also has sev­eral fea­tures that make it very sat­is­fy­ing with­out over­con­sump­tion, and fiber may be one of them.”

• Wake Forest Baptist Medical Center


• Obesity Society