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A little butter may be better than margarine, particularly the margarine uses in many packaged foods. Many of these foods contain trans-fats and the amount is not always displayed on the label.

For the past few decades, a process known as hydrogenation has been used to harden the vegetable oils in margarine.

Hydrogenation increases the oil’s saturated fat content, but unhealthy trans fats are formed as a side product

There are many studies which confirm the possible dangers of using margarine and other foods that are high in trans-fatty acids and these studies confirm that the intake of margarine is associated with increased risk of heart attacks.


Trans-fatty acids & coronary heart disease.

Trans-fatty acids are found in many packaged foods. They are the result of partial hydrogenation of vegetable oils to produce margarines and shortening. It is known they can increase the ratio of LDL to HDL cholesterol, which may have an adverse effect on cardiovascular disease. In the Nurses Health Study, while evaluating over 85,000 females for cardiovascular disease risk, it was found that the consumption of trans-fatty acids was directly related to the risk of coronary heart disease even when controlling for other risk factors. The risk was stronger for those who had consumed margarine at a constant rate over the last 10 years. Foods that were higher sources of trans-fatty acids include margarines, cookies, biscuits, cakes and white bread. These foods are associated with a higher risk of coronary artery disease.

(Willott, Walker C., et al "Intake of Trans Fatty Acids and the Risk of Coronary Heart Disease Among Women", , The Lancet, March 6, 1993;341:581-585).

Trans-fats in foods

A letter to the editor in the NEJM 1993 notes that partial hydrogenation of liquid vegetable oils is a major source of trans-fatty acids which may increase serum levels of low density lipoprotein and decrease high density lipoprotein cholesterol. These hydrogenated vegetable oils are frequently seen in margarine and vegetable shortening. Even through these foods contain no cholesterol, they may have adverse consequences on heart disease. The fast-food industry switched from beef tallow to these vegetable oils because of consumer demand. The intake of trans-fatty acids from the average diet may be high enough to have an adverse effect on dietary treatment, of hypercholesterolemia. The authors conclude that patients and physicians may want to be aware of these artificial sources of fatty acids in their food choices.

Litlin, Lisa, R.D. and Sacks, Frank, M.D.,"Tran-Fatty Acid Content of Common Foods",  New England Journal of Medicine, December 23, 1993:329(26):1969-1970).

Heart attack & trans-fatty acids

This study evaluated the relationship between trans-fatty acids and acute myocardial infarction in 239 patients admitted to 1 of 6 hospitals in the Boston area, and 282 population controls. After adjustment for variables, the intake of trans-fatty acids was directly related to the risk of heart attacks. Intake of margarine, the major source of trans-isomers, was also associated with an increased risk of heart attacks. The authors conclude this data supports the hypothesis that intake of partially hydrogenated vegetable oils may contribute to the risk of myocardial infarction. 

(Ascherio, Alberto, M.D., et al, "Trans-Fatty Acids Intake and Risk of Myocardial Infarction", Circulation, 1994;89:94-101).

The presence of small amounts of trans fat in hydrogenated or partially hydrogenated oils/food products such as margarine will likely cause many to exceed their recommended maximum of 2g daily. Greater transparency in labelling and/or active consumer education is needed to reduce the cardiovascular risks associated with trans fats. (Remig, V. et al. Trans Fats in America: A Review of Their Use, Consumption, Health Implications, and Regulation, Journal of the American Dietetic Association Vol. 110, Issue 4, April 2010, Pages 585–592)

Health Benefits of Butter

Butter from grass-fed cows is much more nutritious. It contains more:

  • Vitamin K2: This little known vitamin may help prevent many serious diseases, including cancer, osteoporosis and heart disease

  • Conjugated Linoleic Acid (CLA): Studies suggest that this fatty acid can have anti-cancer properties and help lower your body fat percentage.

  • Butyrate: A short-chain fatty acid found in butter that’s also produced by bacteria in the intestine. It can fight inflammation, improve digestive health and may help prevent weight gain.

  • Omega-3: Grass-fed butter has less omega-6 and more omega-3, which is important because most people are already eating way too much omega-6 fat.

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