I’m often asked these questions, and I bet you’ve thought about them yourself:

• Which is better for my heart – margarine or butter?
• What type of cooking oil should I use for a heart healthy diet?
• What is the latest guideline on eggs?
• Why do guidelines on margarine, butter, cooking oil, eggs and other foods change?

Changes in recommendations for heart-healthy eating to prevent cardiovascular disease can be frustrating, but they are the result of years of solid scientific research that helps us more fully understand how different nutrients impact cardiac health. As the research uncovers new information, the guidelines are updated to reflect the most recent scientific evidence.To understand the current recommendations, it’s helpful to look at the history of how the guidelines were developed over the years.A report titled “Dietary Goals for the United States”, often known as the McGovern Report, published by U.S. Senate Select Committee on Nutrition and Human Needs in 1977, was the first report to pull together the current science and develop recommendations for food choices to promote overall good health. Before this report, guidelines were based on obtaining adequate amounts of vitamins and minerals. The McGovern Report goals recommended balancing calorie consumption and physical activity to prevent becoming overweight; consuming more fruit, vegetables, and whole grains and less processed foods to reduce added sugars, sodium, cholesterol, and fat; to replace foods high in saturated fat such as eggs and butter with unsaturated fats, and to choose fat-free or lower fat dairy products.The Dietary Guidelines for Americans (DGA), developed jointly by the Department of Health and Human Services (HHS) and the Department of Agriculture (USDA), provide recommendations about how dietary intake can reduce risk for major chronic diseases, including cardiovascular disease, based on current scientific knowledge.The first Dietary Guidelines was issued jointly by the HHS and USDA in 1980 and focused on choosing a variety of nutrient-dense foods that contain essential nutrients, maintaining a healthy body weight, and limiting fat, cholesterol, and sodium that research was showing play an important role in preventing chronic disease. The DGA continue to be updated every 5 years based on the most current scientific research, with new guidelines due to be released in 2020.In 1980, the American Heart Association (AHA) and American College of Cardiology (ACC) partnered to develop clinical guidelines for health practitioners that translate the current science into practice. 23 guidelines on a variety of areas have been published since 1980.In 1986, the National Institutes of Health (NIH) and the AHA established the National Cholesterol Education Program (NCEP) to promote healthy food choices to lower high blood cholesterol and elevated LDL cholesterol levels as a means to reduce cardiovascular disease. The Step-One Diet called for less than 30% of calories from fat, less than 10% of calories from saturated fat, and less than 300 mg of cholesterol per day. If the desired decrease in LDL-cholesterol is not achieved with that dietary change, then the Step-Two Diet is used. It requires reducing saturated fatty acids to less than 7% of calories and cholesterol to less than 200 mg/day. These recommendations were based on reasoning that because saturated fats increase blood levels of LDL cholesterol which raises cardiovascular disease risk, then saturated fat is implicated in CVD.In 1990 the Nutrition Labeling and Education Act provided the FDA with specific authority to require nutrition labeling of most foods regulated by the Agency; and to require that all nutrient content claims (i.e., 'high fiber', 'low fat', etc.) and health claims be consistent with agency regulations. This was also the first time saturated fat content of foods was required on food labels, reflecting the updated DGA recommendations to reduce saturated fat intake.The 2000 DGA for the first time acknowledged that trans fatty acids play an important role in the development of cardiovascular disease, but did not recommend a specific limit. In 2006 the FDA added a requirement to list trans fatty acids on food labels as more research identified the adverse health effects of consuming trans fatty acids.The 2010 DGA and the 2013 AHA/ACC Guidelines both addressed trans fatty acids in more detail, recommending limiting solid fats such as margarine and solid vegetable shortening that are higher in both saturated and trans fatty acids. The focus began to shift away from cholesterol to the specific type of fatty acids, with the 2013 AHA/ACC guidelines not listing any recommendation for cholesterol consumption and instead recommending limiting saturated fat to 5-10% of total calories.In 2015 the FDA took an additional step in determining that partially hydrogenated oils (PHOs) should be completely eliminated from foods because they are the primary source of artificially created trans fatty acids in foods. PHOs are a type of trans fat and are created by heating oils in the presence of oxygen. Eliminating PHOs could prevent thousands of heart attacks and deaths each year. Additionally, the 2015 DGA strongly recommended replacing saturated fats with polyunsaturated fats to prevent CVD and instead of a specific cholesterol limit, recommended consuming as little cholesterol as possible. For the first time, the DGA recommended limiting added sugars to no more than 10% of total calories to achieve a healthy overall eating pattern from nutrient-dense foods.So Where are We Today?The most recent DGA and ACC/AHA guidelines on food choices to prevent chronic disease, including cardiovascular disease, recommend:

• Focus on overall eating patterns instead of individual foods, encouraging choosing a variety of nutrient-dense foods and reducing added sugars, sodium, and saturated fat to decrease the risk of chronic disease.
• Emphasize plant-based foods such as vegetables, fruits, legumes (dried beans and peas such as lentils, chickpeas, kidney beans, black beans, and pinto beans), nuts, and whole grains. These foods are high in fiber and low in saturated fat and cholesterol, and a plant-based, Mediterranean style diet lowers cardiovascular risk compared to other types of eating patterns.
• Choose more lean protein foods such as fish or skinless chicken, and turkey and consume less red meat and processed meats such as sausage, bacon, and lunch meats that are high in harmful saturated fat and sodium.
• Choose foods that are high in healthful monounsaturated fats such as olive oil and canola oil, and decrease foods that are high in saturated fat such as coconut and palm oil.

By Lynn Grieger, RDN, CDE, CPT, CHWCReferences

1. Appendix I: History of Dietary Guidelines for Americans. https://health.gov/dietaryguidelines/dga95/12DIETAP.HTM accessed 5/22/2019
2. 2015 Dietary Guidelines Advisory Committee. DGAC Meeting 1: Materials and Presentations. History of Dietary Guidance Development in the United States and the Dietary Guidelines for Americans. https://health.gov/dietaryguidelines/2015-BINDER/meeting1/historyCurrentUse.aspx June 13-14, 2013. Accessed 5-26-19.
3. J Am Diet Assoc. 1988 Nov;88(11):1401-8, 1411. The National Cholesterol Education Program: implications for dietetic practitioners from the Adult Treatment Panel recommendations. Ernst ND, Cleeman J, Mullis R, Sooter-Bochenek J, Van Horn L.
4. U.S. Food and Drug Administration. Nutritional Labeling and Education Act (NLEA) Requirements. https://www.fda.gov/inspections-compliance-enforcement-and-criminal-investigations/inspection-guides/nutritional-labeling-and-education-act-nlea-requirements-894-295#Nutrient updated 9/8/2014; accessed 5/22/2019
5. U.S. Food and Drug Administration. Final Determination Regarding Partially Hydrogenated Oils (removing Trans Fat). https://www.fda.gov/food/food-additives-petitions/final-determination-regarding-partially-hydrogenated-oils-removing-trans-fat updated 5/18/2018; accessed 5/22/2019
6. Dietary Guidelines for Americans 2015-2020. https://health.gov/dietaryguidelines/2015/guidelines/ accessed 5/22/19
7. 2019 ACC/AHA Guideline on the Primary Prevention of Cardiovascular Disease: A Report of the American College of Cardiology/American Heart Association Task Force on Clinical Practice Guidelines. J Am Coll Cardiol 2019; March 17