Use olive oil or canola oil. Take fish oil supplements. Eat foods that are high in omega-3 and omega-6. For several years, the American Heart Association and other health organizations have recommended reducing the consumption of saturated fats and adding more unsaturated fatty acids in diets as a way to protect from heart disease. Many foods have advertised that their ingredients ( particularly unsaturated fatty acids such as omega-3) are good for cardiovascular health; but new research published Monday is raising doubts about whether changing the types of fats consumed has no effect on heart disease.
The American Heart Association had been recommending that most fats in people’s diets be unsaturated. However, two new studies took a look at the impact of saturated versus unsaturated fats. Saturated, or so-called bad fats found in meats and dairy items were believed to cause plaque in heart vessels. There are two kinds of unsaturated fatty acids (polyunsaturated fats found in salmon and other fish, nuts, seeds and vegetable oils and the monounsaturated fates in olive oil, canola oil, peanut butter and avocados). They were thought to be more advantageous for the heart. Those beliefs are now in question.
One analysis, published in the Annals of Internal Medicine, did not find evidence to support recommending high consumption of polyunsaturated fats and low consumption of saturated fats. The study determined that the evidence does not support guidelines that encourage a diet high in unsaturated fats and low in the other. The researchers used meta-analysis from 32 other studies that dealt with fatty acids in a diet. They also reviewed 17 studies that included measurements of omega-3 levels in participants’ bloodstream and 27 trials involving omega-3 supplements.
The meta-analysis, which covered 660,000 participants, found no conclusive connection between types of fats consumed and the effect on the participants’ risk of heart disease. There was a slight increase in cardiovascular problems for people who ate more saturated fats than unsaturated fatty acids, but not a statistically significant difference.
The second study looked at whether dietary supplements with omega-3 polyunsaturated fatty acids reduced the risk of heart disease. This study, published in JAMA Internal Medicine, did not show that supplements are effective. The researchers looked at data from 4,203 seniors with age-related macular degeneration, of whom 20 percent were known to have coronary disease. The omega-3 supplements that participants took did not produce a discernible difference in results for those with heart disease versus those without. The researchers point out that this is not the first study that did not show a value to omega-3 supplementation. The authors also noted that they did not study the impact of omega-3 in all aspects, particularly on triglyceride levels.
The two studies refute decades of health advice to reduce consumption of butter, cheese and fatty meats and increase the amount of vegetable oils and fish in diets. So, what should people do? Should those who are taking supplements stop? The AHA acknowledged the results but their spokesperson, Linda Van Horn, a professor of preventive medicine at Northwestern University, indicated the Heart Association will continue to advise people to avoid trans fats, limit saturated fats, and eat more produce and whole grains. Van Horn did indicate the findings, particularly about saturated fat, would be considered at a national meeting the organization is holding shortly.
The British Heart Foundation, which co-funded the Annals of Internal Medicine research, also indicated that there would be no change in their advice that fats consumed can have a harmful effect on and lead to heart disease. Their associate medical director noted that the research is not saying to eat more fat. It is suggesting that a diet rich in unsaturated fats and low in saturated fats does not reduce one’s risk of developing heart disease.
By Dyanne Weiss