Following are highlights of twelve research studies, all published or presented within the past five years, that demonstrate that compared to butter, margarine products are the best tablespreads for a heart-healthy diet. This summary is not intended to be a thorough scientific review; rather, it illustrates that there have been numerous studies that point to margarine as the preferred tablespread when compared to butter.

Hodson et al. The effect of replacing dietary saturated fat with polyunsaturated or monounsaturated fat on plasma lipids in free-living young adults. European Journal of Clinical Nutrition. October 2001. 55:908-915.

Specific Findings: This paper reports on two randomized crossover trials among healthy, free-living adults aged 20-41. Saturated fat rich foods (e.g., butter) -- comprising 15% of calories -- were replaced with foods rich in either n-6 polyunsaturated fats (e.g., safflower and sunflower spreads/oils) or monounsaturated fat (e.g., canola spread/oil). Compared to the saturated fat rich diet, the polyunsaturated fat diet significantly reduced total cholesterol by 19 percent and LDL cholesterol by 22 percent. Similarly, the monounsaturated fat diet lowered total cholesterol by 12 percent and LDL cholesterol by 15 percent. Since saturated fat consumption is known to result in higher HDL levels, it was presumed that both unsaturated fat diets would lower HDL levels. According to the researchers: "However, if only using total cholesterol to predict risk of cardiovascular disease, the present results show that replacing saturated fat with n-6 polyunsaturated fat , rather than monounsaturated fat, is more efficacious at lowering the predicted risk of cardiovascular disease due to a larger decline in plasma total cholesterol levels."

Conclusion: "Young adults are very responsive to dietary-induced changes in plasma cholesterol even when an isocaloric replacement of saturated fat with n-6 polyunsaturated or monounsaturated fat is not achieved. Replacing saturated fat with either n-6 polyunsaturated fat or monounsaturated fat is equally efficacious at reducing the total to high density lipoprotein cholesterol ratio."

Denke et al. Individual Cholesterol Variation in Response to a Margarine- or Butter- Based Diet. Journal of the American Medical Association. December 6, 2000. Vol. 284. No. 21. 2740-2747

Specific Findings: This unique study with 46 biological families (92 adults and 134 children) looked at dietary responsiveness to a margarine-based diet or a butter-based diet for ten weeks (five weeks on each diet). Compared with the butter diet, the margarine diet lowered LDL (bad) cholesterol levels 11 percent (15.7 mg/dl) in adults and 9 percent (11.2 mg/dl) in children. Similarly, the margarine diet significantly lowered total cholesterol levels in adults (down 17.6 points) and children (by 11.3 points) versus the butter diet. No significant differences in HDL (good) cholesterol were seen in adults or children. In about one-fourth of the study population, the margarine-based diet lowered total cholesterol levels as much as medication.

Conclusion: These findings agree with those from metabolic diet studies evaluating greater and lesser percentages of energy from margarine, confirming the longstanding advice to the public at large to choose softer margarines over butter. Although differences in response to diet were observed, 80 percent of participants lowered their LDL cholesterol levels on the margarine-based diet (vs. the butter-based diet). In addition to finding a direct correlation between body weight and dietary responsiveness, the researchers concluded that shared genes and environment play a role in overall dietary responsiveness. Overall, this research supports well established recommendations that a cholesterol-lowering diet be promoted to the population at large.

Hu et al. Trends in the Incidence of Coronary Heart Disease and Changes in Diet and Lifestyle in Women. The New England Journal of Medicine 2000. 343:530-7.

Specific Findings: The Harvard researchers reported on a follow-up analysis of 85,941 women between 1980 and 1994. After appropriately analyzing dietary records and health outcomes, they found that a dramatic reduction in heart disease risk was due to a reduction in smoking, an increase in use of post menopausal hormone use, and improvements in diet. The most important dietary changes contributing to this decreased risk were reduced intake of saturated fat (according to the researchers, derived mainly from red meat and high fat dairy products such as butter, whole milk and cheese) and a 69 percent increase in the ratio of polyunsaturated fat to saturated fat (leading dietary sources of polyunsaturated fat are margarine, salad dressings, vegetable oils and nuts). Other significant dietary changes included increased intake of cereal fiber (up 90%), marine-based n-3 fatty acids (up 120%), and folate (up 12%). The researchers also found a decrease of 31% in trans fat consumption.

Conclusion: Dietary improvements contributed significantly to the decline in risk for coronary heart disease (CHD) found across the entire study population. They conclude "these findings underscore the importance of diet and lifestyle in the primary prevention of coronary disease."

Lichtenstein et al. Effects of Different Forms of Dietary Hydrogenated Fats on Serum Lipoprotein Cholesterol Levels. The New England Journal of Medicine. 1999. 340:25:1933-1940.

Specific Findings: The Tufts University researchers evaluated blood lipid levels among 36 hypercholesterolemic individuals during five 5-week phases that contained fats in various forms. They found that butter produced higher total and LDL cholesterol levels than did liquid oil, semi-liquid, soft or stick margarine, or shortening. In further evaluating the specific effects of trans fat, researchers noted that both saturated fat and trans fat increased the total/HDL cholesterol ratio.

Conclusion: When evaluating the practicality of using a margarine or butter, consumption of partially hydrogenated soybean oil used in margarines -- particularly liquid and tub products -- yielded lower total and LDL cholesterol levels than did butter. However, results also showed that butter and stick margarine (both of which contained 80% oil), produced a ratio of HDL to total cholesterol that was the least preferable.

Denke et al. Margarine vs. Butter: Individual Variation in Dietary Responsiveness in Families. Circulation. 1998. Vol. 98, No. 17. (Abstract presentation at American Heart Association 1998 Scientific Sessions)

Specific Findings: To help in the determination if genetics might affect lipoprotein response to diet, 56 individuals (9 families) with unspecified cholesterol profiles consumed two diets that were either rich in margarine or butter. After five weeks on each of the diets, results showed that the average blood cholesterol on the margarine diet was 13 points lower than on the butter diet, and LDL cholesterol was 10 points lower after consuming the margarine diet vs. the butter diet. There were no significant differences on HDL cholesterol levels.

Conclusion: Margarine significantly lowered total and LDL cholesterol levels compared with butter, and in some cases, the lowering effect was as much as medication.

Judd et al. Effects of Butter vs. Margarine on Blood Lipid Profiles Related to Cardiovascular Disease Risk Factors. American Journal of Clinical Nutrition. 1998. 68:768-77.

Specific Findings: U.S. Department of Agriculture researchers examined blood lipid effects from three tablespreads in 46 male and female volunteers. Butter evoked the highest total and LDL cholesterol levels; margarine with a moderate amount of trans fat (TFA-M) lowered both total cholesterol (3.5%) and LDL cholesterol (5.4 %) compared to butter; a trans-fat-free margarine (PUFA-M) lowered total cholesterol (4.7%) and LDL cholesterol (6.7%) compared to butter. The HDL levels were unchanged with both margarines compared to butter.

Conclusion: Consumption of either TFA-M or PUFA-M margarine improved blood lipid profiles associated with cardiovascular risk compared to butter, with a marginally greater improvement with PUFA-M relative to TFA-M.

Jousilahti et al. Serum Cholesterol Distribution and Coronary Heart Disease Risk: Observations and Predictions Among Middle-Aged Population in Eastern Finland. Circulation. 1998. 97:1087-1094.

Specific Findings: Comparing results of five independent risk factor surveys that included 27,721 people, Finnish researchers saw significant decreases in blood cholesterol levels in both men and women over a 20-year time period; average cholesterol levels decreased from 262 mg/dL to about 228 mg/dL in men and 259 mg/dL to 212 mg/dL in women. They found that a community-based population strategy in cardiovascular disease prevention was effective in decreasing cholesterol levels among the entire population, including subjects with the highest blood cholesterol values. As was stated in a previously published study, these researchers continue to attribute major reductions in coronary heart disease to changes away from consumption of saturated fat to unsaturated fats and lower-fat products.

Conclusion: : "In the past 20 years, we can identify four major changes that can explain the observed decrease in saturated fat consumption: (1) introduction and promotion of low-fat milk and (2) oil-based soft margarine in the 1970s, (3) introduction of fat-free milk in the early 1980s, and (4) introduction of low-fat oil-and-water based margarine in the late 1980s." "A 10% reduction in cholesterol levels in the entire population could subsequently reduce coronary heart disease mortality by 20%..."

Noakes et al. Oil Blends Containing Partially Hydrogenated or Interesterified Fats: Differential Effects on Plasma Lipids. American Journal of Clinical Nutrition. 1998. 68:242-7.

Specific Findings: Thirty eight mildly hypercholesterolemic subjects underwent dietary interventions in which they consumed low-fat diets that contained 20 percent of calories as either butter, trans fatty acid (TFA) margarine with 10.4 percent trans fat or TFA-free margarine with zero trans fat. The researchers found that both margarines lowered LDL cholesterol 9-15 percent compared to butter.

Conclusion: From their data, the researchers note that the change in risk from replacing 20 percent of energy from butter with the two study margarines would be 34 percent (as fed) or 17 percent among individuals who more typically consume 30 grams of margarine (10% of calories). Although there was no statistically significant difference in the ratio of total to HDL cholesterol between the two margarines, they noted a trend toward a lower ratio with the trans-free product.

Clarke et al. Dietary lipids and blood cholesterol: quantitative meta-analysis of metabolic ward studies. British Medical Journal. 1997. 314:112-115.

Specific Findings: This meta-analysis found that increasing polyunsaturated fat intake can decrease total and LDL cholesterol. Clarke et al. analyzed 395 studies and found that while monounsaturated fats increased HDL cholesterol, they had no significant effect on total and LDL cholesterol levels. Overall, the researchers found that replacement of 60 percent of saturated fat with unsaturated fat, and avoidance of 60 percent of all dietary cholesterol (in typical British diets) reduced total blood cholesterol levels by 10-15 percent.

Conclusion: Increasing consumption of polyunsaturated fat (from foods such as margarine) can decrease levels of total and LDL cholesterol.

Zock et al. Review Article: Butter, Margarine and Serum Lipoproteins. Atherosclerosis. 1997. 131:7-16.

Specific Findings: An analysis of 20 studies, published between 1957 and 1995 and comprising 49 comparisons of butter and margarine, found that blood lipid profiles were favorably affected by soft margarines, primarily due to their reduced level of trans and saturated fat. This review of the literature examined the potential health effects of margarine vs. butter, finding that replacement of 30 grams (slightly more than two tablespoons) of butter per day with soft tub margarine would theoretically reduce the risk of coronary heart disease (CHD) by 10 percent and that a larger reduction in risk might be seen by replacing butter and other hard fats with margarines low in saturated and trans fats.

Conclusion: Replacing butter with soft and low trans fat margarines can significantly reduce the risk of heart disease.

Jousilahti et al. Twenty Year Dynamics of Serum Cholesterol Levels in Middle-Aged Population of Eastern Finland. Annals of Internal Medicine. 1996. 125:713-722.

Specific Findings: Researchers attributed major reductions in coronary heart disease to changes away from consumption of saturated fat to unsaturated fats and lower fat products. This 20-year research project in Finland examined health and eating habits of 34,253 men and women and found that daily intake of saturated fat decreased markedly between 1972 and 1992. The researchers attributed this decrease to four major changes in eating habits: 1) introduction and promotion of low-fat milk; 2) introduction and promotion of oil-based margarine in the 1970s; 3) introduction of fat-free milk in the early 1980s; and 4) introduction of low-fat oil-based and water-based margarine in the late 1980s.

Conclusion: "Daily intake of saturated fat decreased markedly between 1972 and 1992. Most of this decrease could be explained by change in intake of liquid dairy products and spreadable fats." "The change in the form of spreadable fat consumed (from butter to oil-based margarine) has been particularly important because it led not only to a decreased intake of saturated fat and dietary cholesterol, but also to an increased intake of polyunsaturated fat."

Chisholm et al. Effect on Lipoprotein Profile of Replacing Butter with Margarine in a Low Fat Diet; Randomized Crossover Study with Hypercholesterolaemic Subjects. British Medical Journal. 1996. 312:931-4.

Specific Findings: The researchers examined the effects on lipid and lipoprotein concentrations when either butter or margarine was used as part of a reduced-fat diet (26 percent of calories from fat). The research on 49 volunteers in New Zealand found that the use of margarine (rather than butter) by moderately hypercholesterolemic people is associated with a lipoprotein profile that would be expected to reduce cardiovascular risk. Total cholesterol reduction on the margarine diet was nearly twice that of the butter diet (-9% vs. -5%) whereas reduction in LDL cholesterol was even more significant on the margarine diet (-12% vs. -5% for butter). Changes in HDL cholesterol between diets were considered to be insignificant.

Conclusion: The use of margarine (rather than butter) by people with high blood cholesterol levels is associated with reduced heart disease risk, even when eaten as part of a reduced-fat diet.

Kushi et al. Dietary antioxidant vitamins and death from coronary heart disease in postmenopausal women. The New England Journal of Medicine. 1996. 334:1156-1162.

Specific Findings: In the seven-year prospective study of 34,486 postmenopausal women with no cardiovascular disease, vitamin E consumption from food was inversely associated with the risk of death from coronary heart disease. Analysis of answers to dietary questionnaires found that women who ate diets that contained foods rich in vitamin E (e.g., margarine, mayonnaise, salad dressings, nuts) had one-half to two-thirds lower incidence of coronary heart disease.

Conclusion: "These results suggest that in postmenopausal women the intake of vitamin E from food is inversely associated with the risk of death from coronary heart disease and that such women can lower their risk without using vitamin supplements."

Lerner et al. Effects of lightly hydrogenated vegetable margarines compared to butter on plasma lipids and lipoproteins in men. FASEB Journal. 1996. 10:3:A187 (Presentation made at Experimental Biology '96 meeting).

Specific Findings: In a study of 26 normolipidemic men, these researchers found that when either lightly hydrogenated corn (COM) or sunflower oil margarine (SOM) is substituted for butter in a usual diet pattern, it has an overall beneficial effect on blood lipids. In this study, margarine even contributed 4 percent of energy from trans fatty acids. Compared to butter, margarine diets reduced total cholesterol (-8.6% with COM; -17.9% with SOM) and LDL cholesterol (-4.7% with SOM to -5.4% with COM).

Conclusion: When lightly hydrogenated margarines made from various types of oil are substituted for butter in a usual diet pattern, they can have an overall beneficial effect on blood lipid levels.