The fat that seeks fat

Given the health problems that arise from obesity it is no surprise that fat has a bad reputation. Like many a bad rep however, there are nuances that are lost in the headline perception. Some fats are definitely good for you but they tend to be swallowed up, so to speak, in the general anti-fat sentiment. A new study though has further highlighted the fact that fats aren’t created equal as it has shown that some fats, but not all, can change the way the reward system in your brain works and change eating habits.

The study involved three groups of rats; one group were given a low-fat containing equal amounts of monounsaturated fat and saturated fat, the second group was given a high monounsaturated fat diet in which 50 per cent of the calories came from olive oil, while the third group had a high saturated fat diet where 50 per cent of the calories came from palm oil. The high fat diets were exactly the same in terms of sugars, proteins, calorie density, and fat (just the type of fat was different). In all groups the animals were free to eat as much as they wanted.

After eight weeks all of the rats in all groups were of similar body weight, insulin levels, leptin levels (an appetite regulating hormone), and blood sugar levels. After the eight weeks the rats also underwent behavioural and blood tests that have been established to determine the function of the dopamine reward system in the brain.

The results showed that rats in the saturated fat palm oil group has significantly blunted dopamine function. The researchers say that these rats seek to compensate for the deadening of the dopamine system in the brain by increasing reward seeking behaviour so that saturated fat may actually lead to seeking out more high fat or high sugar foods to get the same level of reward.

No wonder we say that someone who can’t think clearly is a “fat-head” although to be more accurate we should call them a “saturated-fat-head”.