Replacing Saturated Fat, Refined Carbs With Healthy Fats Could Ease Global CHD Burden

Abstract

Insufficient omega-6 polyunsaturated fatty acids (n-6 PUFA), excess trans fat and, to a lesser extent, excess saturated fat, are significant causes of coronary heart disease, suggests a global study recently published online.“Our analysis provides, for the first time, a rigorous comparison of global CHD burdens attributable to insufficient n-6 PUFA versus higher saturated fat. In 80% of nations, n-6 PUFA–attributable CHD burdens were at least twofold higher than saturated fat-attributable burdens. This suggests that focus on increasing healthful n-6 rich vegetable oils may provide important public health benefits,” Qianyi Wang, ScD, and her colleagues said.The researchers estimated national intakes of saturated fat, n-6 PUFA, and trans fat based on country-specific dietary surveys, food availability data, and for trans fat, industry reports on fats/oils and packaged foods. The effects of dietary fats on CHD mortality were derived from meta-analyses of prospective cohorts, and CHD mortality rates were derived from the 2010 Global Burden of Diseases Study. Absolute and proportional attributable CHD mortality were computed using a comparative risk assessment framework.The researchers estimated insufficient n-6 PUFA consumption having been replaced by carbohydrate or saturated fat consumption was responsible for 711,800 CHD deaths per year, accounting for 10% of total global CHD mortality and for 187 CHD deaths per year per 1 million adults. The most absolute CHD deaths per year — 547 per 1 million adults — attributable to insufficient n-6 PUFA occurred in Eastern Europe, while Oceania had the highest proportion of n-6 PUFA–attributable CHD deaths. East Asia had both the fewest absolute — 74 per 1 million adults — and lowest proportion — 6.7% — of CHD deaths attributable to inadequate consumption of n-6 PUFA.Excess consumption of saturated fat as a replacement for n-6 PUFA caused an estimated 250,900 CHD deaths per year, accounting for 3.6% of CHD deaths and 66 CHD deaths per year per 1 million adults.The researchers estimated that excess trans fat consumption caused 537,200 CHD deaths per year, representing 7.7% of global CHD mortality and 141 CHD deaths per year per 1 million adults. High-income nations generally had higher trans fat–attributable CHD mortality than lower-income nations. The highest trans fat–attributable absolute CHD mortality occurred in Egypt, with 1,120 deaths per year per 1 million adults. Canada, Pakistan, and the United States all had more than 475 deaths per year per 1 million adults because of excess consumption of trans fat. Such deaths accounted for more than 17% of corresponding national CHD mortality.Sub-Saharan Africa and the Caribbean had the lowest estimated trans fat–attributable CHD mortality.Additional findings of this study included mean global changes in dietary intakes of saturated fat, n-6 PUFA, and trans fat, and corresponding changes in CHD deaths occurring between 1990 and 2010. Specifically, global proportional CHD mortality attributable to insufficient n-6 PUFA and higher saturated fat consumption decreased by 9% and 21%, respectively. Such decreases occurred in concert with a 0.5% increase in consumption of n-6 PUFA and a 0.2% decrease in consumption of saturated fat. In high-income countries, trans fat consumption declined in parallel with policy strategies to reduce industrial trans fat production. In contrast, global proportional CHD deaths attributable to higher trans fat increased by 4% as global mean dietary intakes of trans fat increased by 0.1%.“Growing evidence indicates that lowering saturated fat provides convincing cardiovascular benefits only when replaced by PUFA, whereas cardiovascular benefits of n-6 PUFA are similar whether replacing saturated fat or total carbohydrates,” said Dr. Wang of the Harvard T.H. Chan School of Public Health, Boston.Read the study in the Journal of the American Heart Association [doi:10.1161/JAHA.115.002891].Katie Wagner Lennon is a web content editor for Frontline Medical News. Insufficient omega-6 polyunsaturated fatty acids (n-6 PUFA), excess trans fat and, to a lesser extent, excess saturated fat, are significant causes of coronary heart disease, suggests a global study recently published online. “Our analysis provides, for the first time, a rigorous comparison of global CHD burdens attributable to insufficient n-6 PUFA versus higher saturated fat. In 80% of nations, n-6 PUFA–attributable CHD burdens were at least twofold higher than saturated fat-attributable burdens. This suggests that focus on increasing healthful n-6 rich vegetable oils may provide important public health benefits,” Qianyi Wang, ScD, and her colleagues said. The researchers estimated national intakes of saturated fat, n-6 PUFA, and trans fat based on country-specific dietary surveys, food availability data, and for trans fat, industry reports on fats/oils and packaged foods. The effects of dietary fats on CHD mortality were derived from meta-analyses of prospective cohorts, and CHD mortality rates were derived from the 2010 Global Burden of Diseases Study. Absolute and proportional attributable CHD mortality were computed using a comparative risk assessment framework. The researchers estimated insufficient n-6 PUFA consumption having been replaced by carbohydrate or saturated fat consumption was responsible for 711,800 CHD deaths per year, accounting for 10% of total global CHD mortality and for 187 CHD deaths per year per 1 million adults. The most absolute CHD deaths per year — 547 per 1 million adults — attributable to insufficient n-6 PUFA occurred in Eastern Europe, while Oceania had the highest proportion of n-6 PUFA–attributable CHD deaths. East Asia had both the fewest absolute — 74 per 1 million adults — and lowest proportion — 6.7% — of CHD deaths attributable to inadequate consumption of n-6 PUFA. Excess consumption of saturated fat as a replacement for n-6 PUFA caused an estimated 250,900 CHD deaths per year, accounting for 3.6% of CHD deaths and 66 CHD deaths per year per 1 million adults. The researchers estimated that excess trans fat consumption caused 537,200 CHD deaths per year, representing 7.7% of global CHD mortality and 141 CHD deaths per year per 1 million adults. High-income nations generally had higher trans fat–attributable CHD mortality than lower-income nations. The highest trans fat–attributable absolute CHD mortality occurred in Egypt, with 1,120 deaths per year per 1 million adults. Canada, Pakistan, and the United States all had more than 475 deaths per year per 1 million adults because of excess consumption of trans fat. Such deaths accounted for more than 17% of corresponding national CHD mortality. Sub-Saharan Africa and the Caribbean had the lowest estimated trans fat–attributable CHD mortality. Additional findings of this study included mean global changes in dietary intakes of saturated fat, n-6 PUFA, and trans fat, and corresponding changes in CHD deaths occurring between 1990 and 2010. Specifically, global proportional CHD mortality attributable to insufficient n-6 PUFA and higher saturated fat consumption decreased by 9% and 21%, respectively. Such decreases occurred in concert with a 0.5% increase in consumption of n-6 PUFA and a 0.2% decrease in consumption of saturated fat. In high-income countries, trans fat consumption declined in parallel with policy strategies to reduce industrial trans fat production. In contrast, global proportional CHD deaths attributable to higher trans fat increased by 4% as global mean dietary intakes of trans fat increased by 0.1%. “Growing evidence indicates that lowering saturated fat provides convincing cardiovascular benefits only when replaced by PUFA, whereas cardiovascular benefits of n-6 PUFA are similar whether replacing saturated fat or total carbohydrates,” said Dr. Wang of the Harvard T.H. Chan School of Public Health, Boston. Read the study in the Journal of the American Heart Association [doi:10.1161/JAHA.115.002891]. Katie Wagner Lennon is a web content editor for Frontline Medical News. Expert PerspectiveIn this study, researchers investigated the impact of various dietary fats on the global burden of coronary heart disease at two specific time periods, 1990 and 2010. Food intake data from a variety of databases were used to determine intakes of saturated (SAT), n-6 PUFA (or omega-6 fatty acids) and trans fats.Not surprisingly, trans fats were associated with significant CHD burden, with North America having a high trans fats–attributable CHD mortality rate. The good news is that trans fat intakes decreased in the United States from 1990–2010. And by 2018, no foods produced in the United States will contain manufactured trans fats, as they have been banned by the Food and Drug Administration. Many food producers have already removed trans fats; however, some foods contain naturally occurring trans fats, which do not appear to have the same negative impact.Although it has been firmly established that trans fats have a harmful effect on cardiovascular (CV) health, the attention-grabbing results of this study were that insufficient intake of n-6 PUFAs in many countries can increase the CHD burden. This type of fatty acid is contained in vegetable oils including sunflower, safflower, corn, soy, and sesame oils, and is known as the essential fatty acid linoleic acid. Of the cardiac deaths that were recorded, 45% occurred prematurely in adults younger than 70, clearly pointing to the impact of diet on CHD. Intake of n-6 PUFA can be inadequate if saturated fat intake is greater than 10% of calories and intake of refined carbohydrates is high. A diet high in fatty meats, sugary beverages, and snacks, but low in whole grains, fruits, and vegetables serves as a good example of a diet potentially low in n-6 PUFA.Omega-3 fatty acid intakes were not included in this study, as the investigators stated that there is “no convincing evidence for causal effects on CHD,” despite promising evidence for the Mediterranean diet pattern. Optimal intake levels for the fats studied were determined to be 12% of energy intakes from n-6 PUFA, 10% from saturated fat and 0.5% for trans fatty acids. Although the intake of trans fats is decreasing due to changes in food production, this study supports that a balance of saturated and n-6 PUFA can reduce the burden of CHD. A diet low in saturated fats not to exceed 10% along with the consumption of n-6 PUFA and omega-3 fatty acids (olive and canola oils, salmon, walnuts, and flaxseed) not to exceed total fat intake of 30%, along with whole grains, fruits, and vegetables may prove to be the healthiest diet for cardiovascular health.—Phyllis J. Famularo, DCN, RDSodexo Nutrition ServicesHowell, NJ In this study, researchers investigated the impact of various dietary fats on the global burden of coronary heart disease at two specific time periods, 1990 and 2010. Food intake data from a variety of databases were used to determine intakes of saturated (SAT), n-6 PUFA (or omega-6 fatty acids) and trans fats. Not surprisingly, trans fats were associated with significant CHD burden, with North America having a high trans fats–attributable CHD mortality rate. The good news is that trans fat intakes decreased in the United States from 1990–2010. And by 2018, no foods produced in the United States will contain manufactured trans fats, as they have been banned by the Food and Drug Administration. Many food producers have already removed trans fats; however, some foods contain naturally occurring trans fats, which do not appear to have the same negative impact. Although it has been firmly established that trans fats have a harmful effect on cardiovascular (CV) health, the attention-grabbing results of this study were that insufficient intake of n-6 PUFAs in many countries can increase the CHD burden. This type of fatty acid is contained in vegetable oils including sunflower, safflower, corn, soy, and sesame oils, and is known as the essential fatty acid linoleic acid. Of the cardiac deaths that were recorded, 45% occurred prematurely in adults younger than 70, clearly pointing to the impact of diet on CHD. Intake of n-6 PUFA can be inadequate if saturated fat intake is greater than 10% of calories and intake of refined carbohydrates is high. A diet high in fatty meats, sugary beverages, and snacks, but low in whole grains, fruits, and vegetables serves as a good example of a diet potentially low in n-6 PUFA. Omega-3 fatty acid intakes were not included in this study, as the investigators stated that there is “no convincing evidence for causal effects on CHD,” despite promising evidence for the Mediterranean diet pattern. Optimal intake levels for the fats studied were determined to be 12% of energy intakes from n-6 PUFA, 10% from saturated fat and 0.5% for trans fatty acids. Although the intake of trans fats is decreasing due to changes in food production, this study supports that a balance of saturated and n-6 PUFA can reduce the burden of CHD. A diet low in saturated fats not to exceed 10% along with the consumption of n-6 PUFA and omega-3 fatty acids (olive and canola oils, salmon, walnuts, and flaxseed) not to exceed total fat intake of 30%, along with whole grains, fruits, and vegetables may prove to be the healthiest diet for cardiovascular health. —Phyllis J. Famularo, DCN, RD Sodexo Nutrition Services Howell, NJ