New York city health officials are promising to be gentle when it comes to enforcing the first-in-the-nation ban on trans fats, which restaurants will have more than a year to rid from their food.
What is Trans Fat?
Trans fatty acids (commonly termed trans fats) are a type of unsaturated fat (and may be monounsaturated or polyunsaturated).
Trans fats occur naturally, in small quantities, in meat and dairy products from ruminants. Most trans fats consumed today, however, are industrially created as a side effect of partial hydrogenation of plant oils ? a process developed in the early 1900s and first commercialized as Crisco in 1911. Partial hydrogenation changes a fat’s molecular structure (raising its melting point and reducing rancidity) but this process also results in a proportion of the changed fat becoming trans fat.
Unlike other fats, trans fats are neither required nor beneficial for health. Eating trans fat increases the risk of coronary heart disease. For these reasons, health authorities worldwide recommend that consumption of trans fat be reduced to trace amounts. Trans fats from partially hydrogenated oils are generally considered to be more of a health risk than those occurring naturally.
The National Academy of Sciences (NAS) advises the United States and Canadian governments on nutritional science for use in public policy and product labelling programs. Their 2002 Dietary reference intakes for Energy, Carbohydrate, Fiber, Fat, Fatty Acids, Cholesterol, Protein, and Amino Acids contains their findings and recommendations regarding consumption of Trans fat.
Their recommendations are based on two key facts. First, “trans fatty acids are not essential and provide no known benefit to human health”, whether of animal or plant origin. Second, while both saturated and trans fats increase levels of LDL cholesterol (so-called bad cholesterol), trans fats also lower levels of HDL cholesterol (so-called good cholesterol); this increases the risk of coronary heart disease (CHD). The NAS is concerned “that dietary trans fatty acids are more deleterious with respect to CHD than saturated fatty acids”. This analysis is supported by a 2006 New England Journal of Medicine (NEJM) scientific review that states “from a nutritional standpoint, the consumption of trans fatty acids results in considerable potential harm but no apparent benefit.”
Because of these facts and concerns, the NAS has concluded there is no safe level of trans fat consumption. There is no adequate level, recommended daily amount or tolerable upper limit for trans fats. This is because any incremental increase in trans fat intake increases the risk of coronary heart disease.