Stuffing down a burger and coke may be more harmful for men than women, if the results of a new mouse study apply to humans. The detrimental impact of junk food seems to be connected to inflammation in the brains of male mice, with the brains of females protected by oestrogen, according to research published today in Cell Reports.
Dr Deborah Clegg, who led the study while at University of Texas Southwestern Medical Centre, Dallas, USA, was building on existing research that links brain inflammation with obesity and heart disease in male mice. "We embarked on this research because [the link with inflammation] had been shown in male mice, so we asked ourselves, do the same processes occur in females?" explains Clegg.
Previous research has shown that one cause of inflammation in the hypothalamus, the part of the brain that controls energy balance, is palmitic acid, a saturated fatty acid found in palm oil, dairy products and meat, and common in high fat food. The team looked at male and female mice, fed either their normal diet or a ‘high fat’ diet. Besides containing 42 per cent fat, the high fat diet was also high in carbohydrates making it a good correlate of human junk food, says Clegg.
"The high fat food was tasty – like cookie dough," says Clegg. "It would be like eating a burger and a coke." After 16 weeks on the high fat- junk food diet the male mice showed markers of inflammation in their brains – but there was no inflammation in the female mice’s hypothalamuses.