How much fat you should eat a day and what foods to eat, plus why your brain needs it
Fat is vital, but it must be the right sort. Experts explain why that is, what the best foods to eat are, and how many grams you should eat
Should we eat a high-fat or low-fat diet for health? This debate has shaped health advice for decades, says Emily Sonestedt of Lund University in Sweden.
Sonestedt is the senior author of a study that observed that high-fat dairy products – specifically fermented options like cheese and high-fat cream – were associated with a lower risk of dementia in Swedes.
Dietary fat has a poor reputation that can be traced back to advice from the mid-20th century, when saturated fat was identified as a driver of heart disease. According to Hong Kong nutritional therapist Katia Demekhina, that advice was shaped by American physiologist Ancel Keys’ Seven Countries Study, which reported an association between saturated fat intake and cardiovascular mortality.
The study was flawed because Keys analysed data from only seven countries and excluded those that did not support his hypothesis, critics suggest. Yet his findings had an exaggerated impact on nutrition policy, Demekhina says.
“It led to decades of low-fat dietary guidelines and the emergence of many low-fat products. While well intentioned, these recommendations failed to distinguish between different types of fat or between whole foods and processed sources.”
