A high-fat diet can lead to some health benefits
For years, nutrition experts have advised that people should consume little saturated fat. But the validity of this hypothesis seems to be doubtful. Researchers have now found that very high saturated fat intake does not have to increase cardiovascular risk. Consuming a very high-fat diet even leads to a significant improvement in some important cardiometabolic risk factors.
The University of Bergen scientists found in an investigation that current dietary guidelines may need to be revised. For more than half a century, the nutritional hypothesis that saturated fatty acids are particularly unhealthy for most people has dominated. But apparently this basic statement is not correct. Saturated fat does not increase cardiovascular risk, it can even reduce some risk factors. The researchers published the results of their study in The American Journal of Clinical Nutrition.
Study examines effects of high fat diet
In their randomized controlled trial, the medical team examined 38 men with abdominal obesity. These subjects received a diet rich in carbohydrates or fat, with half of the fats consumed being saturated. The fat mass in the abdominal region, liver and heart was then measured with detailed analysis along with a number of important risk factors for cardiovascular diseases, the doctors explain.
Positive effects of a high-fat diet:
The very high intake of fat and saturated fats did not increase the cardiovascular risk, says cardiologist Professor Ottar Nygård. Participants in the high-fat group even showed significant improvements in some key cardiometabolic risk factors. These include, for example, positive effects on ectopic fat storage, blood pressure, blood lipids (triglycerides), insulin and blood sugar, the expert adds.
Subjects consume fresh, only little processed food
Both groups had a similar supply of energy, proteins and polyunsaturated fatty acids. We have examined the effects of total and saturated fat in the context of a healthy diet with fresh, little processed and nutritious food, the authors of the University of Bergen explain in a press release. In the investigation, large amounts of vegetables and rice were consumed instead of flour products. The fat sources were also processed only slightly and consisted mainly of butter, cream and cold-pressed oils.
The quality of the food is crucial
The total energy intake was in the normal range, say the doctors. Even participants who increased their energy intake during the study showed significant decreases in fat storage and disease risk. The results show that the overriding principle of a healthy diet is not the amount of fat or carbohydrates, but the quality of the food, the experts add.
Increased fat intake does not lead to a significant increase in LDL cholesterol
Saturated fatty acids have long been thought to promote cardiovascular disease by increasing the unhealthy LDL cholesterol in the blood. But the researchers also explain that there was no significant increase in LDL cholesterol due to increased fat intake. Healthy HDL cholesterol, however, appeared to tend to increase with such a diet.
Many healthy people tolerate high fat intake well
These results show that most healthy people are likely to tolerate high saturated fat intake. "As long as the fat quality is good and the total energy intake is not too high, the fat can even be healthy," says Ottar Nygård. Future studies should examine exactly which people or patients need to limit the intake of saturated fat, adds Professor Simon Nitter Dankel from the Haukeland university hospital in Bergen.
Health risks from high quality fats are exaggerated
The alleged health risks of eating high quality fats have been greatly exaggerated, according to the researchers. It may even be more important for public health to reduce the intake of processed flour-based products as well as heavily processed fats and foods with added sugar, the authors explain. (as)