Contrary to dietary science of the last 40 years, new research published Monday in the journal Annals of Internal Medicine disclaimed the popular nutritional notion that there is a link between saturated fat and threats to heart disease. As research grows, it is becoming more evident that singling out a specific food source can not reveal everything there is to know about our cardiovascular health. In accordance with the new data, Dr. Hu, professor of nutrition and epidemiologist at Harvard School of Public Health, states that eliminating saturated fat from the diet is no guarantee against heart disease.
The international research teams of scientists from Cambridge and Harvard universities compiled data from nearly 80 studies, collecting documentation from nearly half a million participants. The studies analyzed both what people ate and the composition of fatty acids found in the blood and fatty tissues. Research concluded a definite link between trans fats, partially hydrogenated oils found in fast foods and processed foods, and heart disease, but no evidence of dangers in saturated fat. Nor did the research find less heart disease with participants who supplemented saturated fats in their diets with monounsaturated fats, like olive oil, with polyunsaturated fats, like corn oil, or with other fats, such as fish oils.
For years, as early as the 1960s, health officials have been urging the public to diminish the amount of saturated fat in their diets in order to decrease the risk of heart disease. Studies showed that saturated fat found in the blood raised low-density lipoprotein: LDL, the bad cholesterol, the artery-clogging culprit. People with high levels of LDL were said to be at a higher risk of heart disease. Now there is evidence in the new research that shows that saturated fat can actually increase levels of HDL, the good cholesterol, and lower fat deposits in the blood. Theoretically, saturated fat could be viewed as a deterrent to heart disease, an opposing view to its previously well-established supposition. However, according to Dariush Mozaffarian of Harvard School of Public Health, saturated fat has a neutral effect in the body, “not a beneficial effect, but not a harmful effect.”
Not everyone supports the new research that disclaims saturated fat as a link to heart disease. World Health Organization and the American Heart Association still promote low intakes of saturated fat. Dietary guidelines recommended by the American Heart Association suggest that saturated fats should make up less than 7 percent of a diet based on 2,000 calories a day. In this scenario, saturated fat intake would be limited to either two tablespoons of butter or roughly two ounces of cheddar cheese daily. The American Heart Association still stands by its guidelines and is complacent in its view that eating more unsaturated fats, like beans and vegetables, and less saturated fats, like butter and bacon, can protect against heart disease by lowering LDL.
Nutritional biochemist at Tufts University and lead author of the American Heart Association’s dietary guidelines, Dr. Alice H. Lichtenstein, who did not participate in the study, fears that the promotion of these results could be interpreted to suggest people can eat as much bacon and as many burgers as they want. The fear, in part, comes from a history of a “Western” diet pattern, which includes a lot of red meat, refined grain, potatoes, sugary drinks, and is low in fruits and vegetables, being a leading factor in heart complications.
But Dr. Hu says research discoveries should not be a “green light” to eat more steak, bacon, and cheese. He believes the new data should help us shift our focus to adopt a more incorporated and less eliminatory diet plan, rather than singling out specific food groups. Dr. Hu promotes mimicking a Mediterranean-style diet of nuts, fish, avocados, high fiber grains, and olive oil. Alarmingly, nearly 45 percent of the calories are derived from fat in this nutritional paradigm, but although a Mediterranean diet plan is composed of numerous components high in fats, the fats are derived from olive oils or plant sources, and the saturated fats are low. In addition, a large, clinical trial last year revealed that the Mediterranean diet reduced heart attacks and strokes when compared to a lower fat diet with more starches.
Being mindful of a heart-healthy lifestyle incorporates many decisive factors, such as quitting smoking and exercising regularly. Chances are by eliminating whole groups of food, people will tend to over-indulge in other nutrient groups, eating more processed grains and refined carbohydrates, which can also be harmful to our cardiovascular system. Dr. Rajiv Chowdhury, lead author of he new study and a cardiovascular epidemiologist in the department of public health and primary care at Cambridge, say, says, “It’s the high carbohydrates or sugary diet that should be the focus of dietary guidelines. If anything is driving our LDL in a more adverse way, it’s carbohydrates.”
Too many calories from any one source creates an imbalance, whether it’s fats or carbohydrates, and concern about heart health should consider an overall diet, not just the intake of fats. New research disclaiming the link between saturated fats and heart disease, although still contested in some circles, is an indication that heart disease and other cardiovascular complications continue to be a major concern in Western culture. Incorporating a conscientious nutritional pattern that incorporates a balanced intake of all food groups could help us overcome the afflictions.
By Stacy Feder