Current dietary advice says foods containing high levels of saturated fats such as cream, butter, red meat, eggs and cheese should be avoided because they increase the risk of heart disease, Type 2 diabetes and cancer.
But a study published in a leading medical journal has found the opposite is true, with a diet full of natural fats improving the health of people taking part.
Professor Sherif Sultan, a heart specialist from the University of Ireland, said: “We urgently need to overturn current dietary guidelines.
“People should not be eating high carbohydrate diets as they have been told over the past decade.
“Instead our diets should be largely based on good quality high-fat foods. This will prevent the rising epidemic of Type 2 diabetes and reverse the growing numbers of people suffering weight-related heart problems.”
The study, published in the American Journal of Clinical Nutrition, found overweight middle-aged men who ate high levels of saturated fat and low levels of carbohydrate became slimmer and healthier.
Researchers also saw reduced blood pressure and glucose levels, which are associated with a lower risk of heart disease, Type 2 diabetes and cancer, in the patients.
The people in the study were given unprocessed fats from natural sources, including butter, cream and cheese, along with coconut oil. Scientists believe these are “good fats” that absorb well in the body.
They did not include manufactured fats such as margarine, highly refined oils and trans-fats used in processed foods.
Experts say refined carbohydrates turn into sugar in our bodies, causing a spike in the energy storage hormone insulin, leading to fat accumulation in the cells.