Margarine vs. Butter: Which is the Better Spread?
The debate over which is better—butter or margarine—has been going on for years, and depending on whom you talk to, the answer can vary. While opinions can be decided based on a wide variety of criteria, such as taste or texture, the question of the chemical difference between the two can often elude the buyer as he or she strolls down the supermarket aisle. What is the difference in composition between butter and margarine, and what does their difference mean for our bodies?
One of the main players in the debate is cholesterol. Cholesterol exists in two different compounds: low-density lipoprotein (LDL), also known as "bad" cholesterol, and high-density lipoprotein (HDL), or "good" cholesterol. LDL is responsible for clogging arteries with plaque, causing atherosclerosis, while HDL carries cholesterol away from the arteries to the liver where it is degraded. While cholesterol carries a negative connotation, it is a vital component of certain hormones and cell membranes (MedicineNet).
The cholesterol composition of butter and margarine differs greatly. Cholesterol is found only in animal products. Butter consists of animal fat and, thus, contains cholesterol (Grogan). Margarine, on the other hand, consists of vegetable oil and, therefore, contains no cholesterol, making it superior to butter.
However, cholesterol content is not the sole factor in deciding which spread is best. The type of fats in the two products is also an important factor. Butter contains saturated fats (see Figure 1), which greatly increase LDL levels. Even though butter does increase HDL levels, that does not warrant its consumption in high quantities (Cleveland clinic). Margarine contains more polyunsaturated and monounsaturated fats (see Figure 2), which have the health benefit of reducing LDL (Grogan). However, margarine also contains a high amount of trans fats, which are unsaturated fats with a double bond between adjacent carbon molecules in the trans chemical position (see Figure 3). Trans fats are formed synthetically by heating liquid vegetable oils in the presence of hydrogen, causing hydrogenation of the oils to produce trans fats. Even though trans fats make margarine solid and less likely to spoil, they are worse than saturated fats since they both lower HDL levels and increase LDL level, making margarine a very unhealthy choice (Harvard School of Public Health).
The debate over which is worse, butter or margarine, is still under investigation in many studies. Lately, however, studies have shown support for butter over margarine because of the high trans fats content in margarine.