An editorial in the British Medical Journal is calling for trans fats to be “virtually eliminated in the UK by next year” claiming that reducing the proportion of trans fats consumed by a mere 1% could prevent 7000 deaths each year in England alone. But what are trans fats, why are they used, and why the fuss?
Trans fats explained
A small amount of trans fat occurs naturally in animal products such as meat and milk, but by far the greatest proportion of trans fats that we eat are a product of the processed foods industry, and are the result of partially hydrogenated unsaturated fats. Trans fats are non essential fats, and they have no nutritional value.
Trans fats are found in fast food, fried food, snack food, and baked goods, and are used because they give food a longer shelf life. They have a high melting point, so there is less need for food to be refrigerated. They are cheaper than other semi solid fats such as palm oil, and they can be used in frying for longer periods than most oils, making them cost effective.
What are the health risks of trans fats?
Here are just some of the medical conditions that can result from the consumption of trans fats:
- Coronary heart disease can be caused by trans fats, as they increase levels of LDL cholesterol and reduce levels of HDL cholesterol. In 2006, research published in the New England Journal of Medicine estimated that between 30,000 and 100,000 cardiac deaths in the U.S. each year are the direct result of eating trans fats.
- Cancer has been associated with trans fats, and although the link has not been firmly established, there seems to be a clear correlation between consumption of trans fats and the risk of prostate or breast cancer.
- Alzheimer’s Disease develops more quickly in people who consume a large amount of both trans fats and saturated fats.
- Diabetes risk appears to be associated with trans fat consumption, with those eating large amounts of trans fats more likely to develop type 2 diabetes.
- Liver dysfunction can arise from consuming trans fats because they are metabolized in a different way than other natural fats, and this can interfere with cell production in the liver.
- Infertility in women rises dramatically with increased intake of trans fats. Replacing just 2% of carbohydrate intake with trans fat intake can increase the risk of infertility by almost 75%.
New mothers should also consider the level of trans fats they are passing on to their babies in breast milk. Breast feeding is always considered the healthy option, but if the mother consumes a high proportion of trans fats, this will pass through to her milk.
A study comparing trans fat as a percentage of total fat in human milk found that the average level in Spain was 1% compared to 7% in Canada, a country that faces a continued struggle to ban excessive trans fat consumption and currently regulates it at 5% of overall calorie consumption.
What are we doing about trans fats?
The National Academy of Science (NAS) suggests that there is no safe level of consumption for trans fats, and the World Health Organization says they should make up less than 1% of our overall calorie consumption. So what are we doing to reduce trans fat intake?
The latest call for a trans fat ban in the UK is based on the premise that although the average consumption of trans fats per person is quite low, it may be very high for young people who are more attracted to fast and snack food, and for low income families who may only be able to afford processed foods.
They suggest that cutting off trans fats at the source is the only way to definitely reduce consumption. This seems to have worked in Denmark, where deaths from ischemic heart disease have fallen 50% since the regulation of trans fats. Their laws state that only 2% of any oil or fat used in food production can be trans fat. That is 2% of the ingredient, not the final product.
In the U.S. we have started to do more to regulate trans fat consumption:
- New York City banned the use of trans fats in the restaurant industry, effective July 2008.
- King County of Washington passed a ban on artificial trans fats, effective February 2009.
- California has become the first state to ban trans fats in restaurants, effective January 2010. Currently this doesn’t include donuts and baked goods, but these will be regulated from January 2011.