Lately, there are drastic changes in how we see fats. There was a time when experts considered fats as an enemy and they did everything to reduce its consumption. However, the time has changed now. Experts categorize monounsaturated and polyunsaturated fats as “good fats”. These encourage overall health. When you take low-fat diets, you are denied bad as well as good fats. You all must be aware of the fact that saturated fats are “ok fats” and trans fats are “bad fats” for your general health.
However, the impact of fat on your brain isn’t what generally is thought of. No doubt the brain is made up 60% of fat and requires fatty acids as fuel, yet a diet full of fat – regardless of whichever fats it contains – will not only fail to help learning, memory and other cognitive functions but in reality will harm these.
How is Diet a Factor?
There is increasing evidence day by day to show how lifestyle changes play a role in maintaining cognitive functions in the aged people. According to research, experts suggested that cognitive decline that most probably occurs between the age of 45 to 70, is the consequence of diet, other lifestyle variables and genetics as well.
Some researchers even showed that higher quantities of lipid is related to poor cognition. The negative impact of saturated and trans fats on the cognitive abilities are proved in the research but impacts of monounsaturated fatty acids aren’t yet proved. As per some studies, polyunsaturated fats may enhance cognition.
According to some preclinical studies, changes in the hippocampus can result in impairment in memory and learning because of a diet with high fat. The effects are reduced neurogenesis, more inflammation, lower hippocampal sensitivity towards insulin, altered blood-brain barrier (BBB) permeability and less neuronal plasticity.
Effects in the Elderly
Most studies that study the effects of diet on cognitive abilities are done on elderly people. These people are given a mini-mental status exam (MMSE) and a food frequency questionnaire also. This is not an appropriate way to measure the intake. Another drawback of these studies is that there is no clarity as how much and which type of fat is consumed.
The negative effects of a diet full of fat on cognition are probably aggravated by several factors, including aging.
There are a number of other factors that play a role with a high-fat diet causing impairment to the brain, particularly with aging. The factors are insulin resistance, oxidative stress, changes to BBB integration/vascularization and inflammation. All these factors with high-glycemic index-type and high-fat diet contribute to changes in brain function.