Trans fats are a type of unsaturated fat. They can occur naturally in meat and milk products or can be created artificially. The naturally occurring trans fats are formed by bacteria in the stomach of ruminant animals such as cows or sheep. They account for only 2-5% of the fat content in the dairy products and 3-9% of the fat content in beef and lamb. We have eaten these naturally occurring trans fats for centuries and studies show that natural trans fats are not harmful to our health if consumed in moderate amounts. Artificial trans fats are created by adding hydrogen molecules into vegetable oils. This process changes the oil from being a liquid at room temperature into being a solid. Hydrogenated or partially hydrogenated oils have similar consistency to saturated fat and have a much longer shelf life which is why manufacturers like using them. Artificially created trans fats can be found in in many products including, fried foods, donuts, cakes, pies, biscuits, pizzas crackers, cookies and stick margarine. Eating artificially created trans fats is bad for our health for a number of reasons:
1) Link to heart disease
We all know that trans fats are bad for our health. Eating trans fats increases the “bad” LDL cholesterol and lowers the “good” HDL cholesterol. Having high amount of “bad” cholesterol in our bodies damages our arteries and leads to heart disease. Over the last few decades, many studies have proved this link. For example the Nurses Health Study where more than 30,000 women were evaluated on their diet, lifestyle and disease risk, showed that women with the highest levels of trans fats in their blood cells had triple the risk of developing heart disease. Another study conducted by the Harvard School of public health showed that eliminating trans fats from the supply chain would prevent 1 in 5 heart attacks and heart attack related deaths.
2) Link to obesity and type 2 diabetes
Eating trans fats is often linked to obesity. This is because trans fats are often found in unhealthy foods such as fried food or fast food. People who consume this type of food on a regular basis tend to consume more calories, which can result in obesity. A study conducted by Kylie Kavanagh showed that even if the daily calorie intake was the same, monkeys that were fed a diet rich in trans fats put on more weight than monkeys fed a diet high in monounsaturated fats. This study also showed that eating a diet where 8% of daily calories came from trans fats results in insulin resistance in monkeys. There are many other studies available that further support link between trans fats and obesity.
3) Link to other diseases
Trans fats have also been linked to cancer, liver dysfunction, systemic inflammation, infertility in women, depressive disorders and even Alzheimer’s.
So how can you avoid trans fats?
1) Read the label – It is not sufficient to look at the nutritional breakdown to see if a particular serving size contains trans fats. According to the FDA rules, the label can read “0” if the serving size contains less than 0.5g of trans fats. What manufacturers do is lower the serving size so that they can claim that the product has “0 trans fats per serving”. So products you think are trans fat free may actually contain trans fats. Eating products that have these small amounts of trans fats adds up very quickly without us even knowing. The best way to ensure that there are no trans fats in the product you are buying is to read the ingredients list. You want to avoid hydrogenated oils, partially hydrogenated oils and vegetable shortenings.
2) Avoid products with vegetable oils like canola and soybean. These have been shown to have 0.56 to 4.2 of trans fats without the packaging saying so.
3) Choose real butter over margarine – Margarine is a vegetable oil based substitute for butter. It is highly processed and contains trans fats.
4) Avoid processed foods – Some processed foods like pizza, crackers, jelly and margarine, just to name a few, contain trans fats even if the label claims “0 trans fats per serving”. You either need to read the label to make sure that the product you are buying does not contain trans fats or avoid these products completely.
5) Avoid fried foods in restaurants – You may be exposed to trans fats if you eat fried food in restaurants. Restaurants often use oils such as canola oil to fry their food and they don’t change the oils as often as they should.