Diets Rich in Polyunsaturated Fats May Reduce Appetite

New research sug­gests that reg­u­larly eat­ing foods high in polyun­sat­u­rated fats may affect hunger.

A study out of the University of Georgia shows that these foods, which include avo­cado, quinoa, chick­peas, salmon, wal­nuts and olive oil, may have an effect on hor­mones that results in reduced appetite.

This was done by mea­sur­ing the phys­i­o­log­i­cal lev­els of hunger and sati­ety through hor­mone changes in study sub­jects and ask­ing them to rate how hun­gry they were and how much they could eat.

Participants who were fed a diet high in polyun­sat­u­rated fats had a sig­nif­i­cant decrease in fast­ing ghre­lin, a hor­mone that increases hunger, and a sig­nif­i­cant increase in pep­tide YY, a hor­mone that increases the feel­ing of being sati­ated or full. Measurements were taken after meals and dur­ing peri­ods of fast­ing.

“Appetite hor­mones play an impor­tant role in reg­u­lat­ing how much we eat,” lead researcher Jamie A. Cooper said. ​“These find­ings tell us that eat­ing foods rich in polyun­sat­u­rated fats may favor­ably change appetite hor­mones so that we can feel fuller for longer.”

While these changes in hor­mones indi­cate bet­ter appetite con­trol, there were no changes in sur­vey answers between those who ate meals high in polyun­sat­u­rated fats and the con­trol diet through­out the study.

The results may have impli­ca­tions in terms of weight loss. If a diet high in polyun­sat­u­rated fats leads peo­ple to eat less, it could help tackle the obe­sity epi­demic.

The study involved 26 healthy men and women between the ages of 18 and 35 who vis­ited the lab for test­ing and to eat their meals. At the begin­ning of the study, sub­jects were fed a diet high in sat­u­rated fats. They were then given either meals high in polyun­sat­u­rated fats or a con­trol diet con­sis­tent with typ­i­cal American eat­ing pat­terns over a seven-day period. Afterward, they were once again fed meals high in sat­u­rated fats.

The diet high in polyun­sat­u­rated fats con­sisted of Alaska salmon, tuna, wal­nuts, flaxseed oil, grape­seed oil, canola oil and fish oil sup­ple­ments.

Both this diet and the con­trol diet con­tained the same total num­ber of calo­ries and calo­ries from fats. The dif­fer­ence was the types of fats included. The diet high in polyun­sat­u­rated fats was com­prised of 21 per­cent polyun­sat­u­rated fats, nine per­cent mono­sat­u­rated fats and five per­cent sat­u­rated fats, while the con­trol diet had seven per­cent polyun­sat­u­rated fats, 15 per­cent mono­sat­u­rated fats and 13 per­cent sat­u­rated fats.

It’s impor­tant, how­ever, to note the lim­i­ta­tions of the study. It was done on a small scale within a lim­ited age group. There were no indi­ca­tions of diver­sity. We’re also unable to deter­mine whether the results dis­played can be attrib­uted to a par­tic­u­lar type of polyun­sat­u­rated fat, food source or a com­bi­na­tion of fac­tors.

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