Stearic Acid Is Unique

Americans consume about 12-13 percent of their total calories from saturated fatl^1,2. This reflects a small decrease in saturated fat intake from earlier estimates, but it is still higher than dietary recommendations. Many public health organizations recommend a diet that provides less than 10 percent of total calories from saturated fat³. Governmental agencies and professional groups have made similar recommendations. The goal is to help Americans reduce their risk for heart disease.

Blood Cholesterol and Heart Disease

Heart disease results from chronic exposure to both modifiable and non-modifiable risk factors³.

Risk Factors for Heart Disease

Modifiable Risk Factors

• Smoking
• Hypertension
• High LDL Cholesterol
• Low HDL Cholesterol
• Obesity
• Physical Inactivity
• Diabetes Mellitus

Non-Modifiable Risk Factors

• Age - (Male 45+ Years) (Female 55+ Years*)
• Family history of premature heart disease

* Or premature menopause without estrogen replacement therapy

A major risk factor is elevated blood cholesterol, especially LDL cholesterol. High levels of LDL cholesterol raise the risk for heart disease⁴. Lowering LDL cholesterol reduces the risk for heart disease³. Drug therapy or changes in diet can lower LDL cholesterol.

Saturated Fat

During the past 40 years, many scientific studies have examined the effects of dietary saturated fat on blood cholesterol. These studies have shown that a high intake of saturated fat increases blood cholesterol and the risk for heart disease^5-9. This is why health professionals recommend a reduction in saturated fat intake.

The saturated fat in food contains different saturated fatty acids. Most dietary saturated fatty acids contain between 12 and 18 carbon atoms (Figure 1). Historically, the grouping of saturated fatty acids as "saturated fat" has not considered their effects on blood cholesterol^9-11. Research has shown, though, that not all saturated fatty acids raise blood cholesterol. Lauric, myristic, and palmitic acids raise blood cholesterol, whereas stearic acid does not (Figure 2). However, dietary recommendations for saturated fat include stearic acid with the other saturated fatty acids that raise blood cholesterol. A diet to lower blood cholesterol should emphasize decreasing the intake of saturated fatty acids other than stearic acid.

Saturated Fatty Acids (Figure 1)

Carbon Atoms	Name	Effect on Blood Cholesterol
12	Lauric Acid	Raises
14	Myristic Acid	Raises
16	Palmitic Acid	Raises
17	Stearic Acid	No-Effect

Meeting Saturated Fat Goals

The dietary goals for saturated fat depends on each person's calorie needs. For example, the goal for a moderately active woman who requires 2000 calories per day is about 22 grams of saturated fat. People can meet their goals without avoiding all foods that contain saturated fat. A diet that meets the saturated fat goal should include a variety of foods: fruits, vegetables, breads, cereals, and vegetable oils that contain little or no saturated fat and meat and dairy products that are sources of saturated fat. If people exceed their saturated fat goal one day, they can adjust their food choices the next day to achieve an overall balance. This approach enables all foods to be a part of a healthy diet.

People can achieve their saturated fat goals through a variety of strategies¹². Simply reducing total fat intake helps to lower saturated fat. There also are specific ways to target saturated fat. One very effective strategy is to choose lean red meat, poultry, and fish. Another is to use skim milk and lower-fat dairy products instead of the full-fat products. Use each strategy alone or together to meet dietary goals for saturated fat. These strategies provide greater options for food choices, especially for favorite foods like snacks, desserts, and treats. A full understanding of how to balance a wide variety of foods from all food groups promotes enjoyable eating.

The Nutrition Label

Nutrition information on food product labels can help people make choices to meet the dietary goals for saturated fat. People can use the Nutrition Facts panel to monitor their daily intake of saturated fat. In addition, claims such as saturated fat free, low saturated fat or reduced saturated fat inform consumers about the amount of saturated fat in a product. Foods that are low in saturated fat, cholesterol, and total fat or extra lean can make a claim such as: a lower saturated fat intake may reduce blood cholesterol and the risk of heart disease.

The saturated fat value on the label includes stearic acid. Some foods, like chocolate products, contain a high proportion of stearic acid (Table 3). So, the saturated fat on the labels of these products overemphasizes their potential to raise blood cholesterol. Separate consideration of stearic acid on the label would more accurately reflect the potential of a food to affect blood cholesterol. It also would provide more flexibility for planning diets to reduce the risk for heart disease.

Saturated Fat and Stearic Acid in Selected Foods (Figure 2)

Food	Amount	Saturated	Stearic	Excluding
Butter *	1 Pat	2.5g	0.5g	2.0g
American Cheese Food *	1 oz	4.4g	0.8g	3.6g
Hamburger, Lean, Raw *	4 oz	9.4g	2.8g	6.6g
Chicken Breast, Meat only, raw *	1/2 Breast	0.4g	0.1g	0.3g
Milk Chocolate Bar º	1.55 oz	8.7g	4.4g	4.3g
Semi-sweet Chocolate Bar º	1.45 oz	8.3g	4.8g	3.5g
Peanut butter cup candy bar º	1.6 oz	5.5g	2.5g	3.1g

* USDA Agricultural Handbook No. 8
º The Hershey Company

Summary

A high intake of saturated fat raises blood cholesterol, and dietary recommendations advise a reduction in saturated fat intake. However, one saturated fatty acid, stearic acid, does not raise blood cholesterol. An awareness of the foods that are rich in stearic acid will make it easier to include them in a blood cholesterol-lowering diet.

Also, the widespread focus on saturated fat and health has led many people to choose foods just for saturated fat content. Many people unnecessarily restrict certain foods - often favorite snacks and desserts - that contain saturated fat. Highly restricted diets often do not follow the basic principles of variety, balance, and moderation. With knowledge and planning, people can fit all foods into a healthy diet. An added benefit of achieving this goal is that healthy eating will be more appetizing and enjoyable!

Referances

¹ SS, Egan SK, Heimbach JT, Harris SS, Kris-Etherton PM. Fatty acid consumption pattern of the US population: 1987.88 USDA Nationwide Food Consumption Survey. Nutr Res 1995; in press.

² Centers for Disease Control. Daily dietary fat and total food energy intakes: National Health and Nutrition Examination Surveys III, Phase 1 - U.S.,1988-91. MMWR 1994;43:120.4.

³ ATp.1I Report of the Expert Panel on Detection, Evaluation, and Treatment of High Blood Cholesterol in Adults. National Cholesterol Education Program, National Heart, Lung and Blood Institute. U.S. Department of Health and Human Services, Bethesda, MO, 1993.

⁴ Neaton JO, Blackburn H, Jacobs 0, Kuller l, et al. Serum cholesterol level and mortality findings for men screened in the Multiple Risk Factor Intervention Trial. Arch Inter Med 1992;152;1490.1500.

⁵ Keys A. Coronary heart disease in seven countries. Circulation 1970; Suppl l:1-211.

⁶ Keys A, Anderson JT, Grande F. Serum cholesterol response to changes in the diet. IV. Particular saturated fatty acids in the diet. Metabolism 1965;14:77-86.

⁷ Artaud-Wild SM, Connor Sl, Sexton G, Connor WE. Differences in coronary mortality can be explained by differences in cholesterol and saturated fat intakes in 40 countries but not in France and Finland. A paradox. Circulation 1993; 88:2771-9

⁸ Hegsted OM, Ausman lM. Diet, alcohol and coronary heart disease in men. JNutr 1988;118:1184-89.

⁹ Hegsted OM, McGandy RB, Myers Ml, Stare FJ. Quantitative effects of dietary fat on serum cholesterol in man. Am J Clin Nutr 1965;17:281-95.

¹⁰ Derr JA, Kris-Etherton PM, Pearson T A, Seligson FH. The role of fatty acid saturation on plasma lipids, lipoproteins and apolipoproteins. II. The plasma total and lOl.cholesterol response of individual fatty acids. Metabolism 1993;42:130-4.

¹¹ Yu S, Derr J, Etherton TD, Kris-Etherton PM. Plasma cholesterol.predictive equations demonstrate that stearic acid is neutral and monounsaturated fatty acids are hypocholesterolemic. Am J Clin Nutr 1995;61:1129.39.

¹² Smith. Schneider lM, Sigman.Grant MJ, Kris.Etherton PM. Dietary fat reduction strategies. J Am Diet Assoc 1992;92:34.8.