New data presented at the recently concluded European Society of Cardiology congress in Barcelona, Spain, suggest that we might have been barking up the wrong tree all these years regarding limiting dietary fat intake.
In a study involving 135,000 individuals from 18 low-, middle- and high-income countries, the findings show that a high fat intake appears to be associated with a lower risk of premature deaths by any cause, while a high carbohydrate diet, typical of the Filipino diet, is associated with a worse long-term outcome.
The study findings are a departure from the recommendation to limit total fat intake to less than 30 percent of energy, and saturated fat intake to less than 10 percent of energy, said Dr. Mahshid Dehghan, Ph.D, from the Population Health Research Institute, McMaster University in Hamilton, Ontario, Canada.
Dr. Dehghan, one of the primary authors of the study, explained that limiting total fat consumption does not appear to improve overall health of the population. Increasing fat intake to cover for about 35 percent of energy requirements, and reducing carbohydrate intake may lower risk of total death.
Those with high carbohydrate intake, exceeding 60 percent of energy, may benefit most from reducing carbohydrate intake and increasing fat consumption, said Dr. Dehghan.
Rice eating
Filipinos may take a cue from this study. Our diet, like other rice-eating Asian neighbors, is generally high in carbohydrates. In the provinces, a plateful of rice with a small serving of viand would constitute an average meal.
In the study, the diets of 135,335 individuals, aged 35 to 70, were properly documented, counting their fat and carbohydrate intakes. The participants were from North America and Europe, South America, the Middle East, South Asia, China, Southeast Asia and Africa.
The diets were validated using food frequency questionnaires, and their associations with cardiovascular disease and deaths from any cause were scientifically determined.
There were 5,796 deaths and 4,784 major heart attacks, strokes and other cardiovascular complications recorded over a median follow-up of 7.4 years.
The researchers analyzed the carbohydrate intake in the highest compared to the lowest quintile, and this was associated with a significant 28-percent increased risk of total deaths from any cause.
Opposite pattern
On the other hand, the researchers were surprised to note the opposite pattern in the relationship of total fat intake and deaths. A high fat intake was associated with a significant 23-percent reduction in total deaths, an 18-percent reduced risk of stroke, and a 30-percent reduced risk of noncardiovascular deaths.
It was not a spurious finding simply by chance, because all specific types of fat were consistently linked with significantly reduced death risk: namely, 14-percent lower for saturated fat, 19-percent lower for monounsaturated fat, and 20 percent for polyunsaturated fat.
A higher saturated fat intake appeared to be also associated with a 21-percent reduction in stroke risk.
Bad cholesterol
Intuitively, one would expect that a high fat intake would increase the so-called “bad” cholesterol or low density lipoprotein (LDL), which is known to clog the arteries. The study showed that an increase in LDL cholesterol does happen with a high fat intake, but this is likely neutralized with an increase in high density lipoprotein (HDL), also known as the “good” cholesterol.
So, the net effect is a decrease in the total cholesterol/HDL ratio, which is favorable.
With this new data, Dr. Dehghan and her colleagues believe that it’s about time we review our dietary recommendations on fat and carbohydrate intake. She said that for decades, dietary guidelines have focused on reducing total fat and saturated fatty acid (SFA) intake, based on the presumption that replacing SFA with carbohydrate and unsaturated fats will lower LDL cholesterol and should, therefore, reduce heart attack, stroke and premature death.
The study suggests otherwise. She explained that it “provides a unique opportunity to study the impact of diet on total mortality (death) and cardiovascular disease in diverse settings, some settings where over-nutrition is common and others where undernutrition is of greater concern.”
In underdeveloped and developing countries where undernutrition is prevalent, the general population is much better off restricting the rice and other sources of carbohydrates, and adding additional sources of fats like eggs, dairy products and coconut oil.