Unsaturated fats with trans-isomer or E-isomer fatty acids are otherwise known as trans fats. Trans fats can be either monounsaturated or polyunsaturated due to a double carbon-carbon bond but they can never be saturated.
It is important to know that trans fats are not considered to be essential fatty acids and the consumption of these fats in large amounts is not good for health because that way a person increases the risk of coronary heart disease. This is achieved by increasing the levels of LDL cholesterol and lowering the levels of HDL cholesterol, which is considered to be good cholesterol. Practically all experts agree that a person should consume only trace amounts of trans fats.
Product labeling programs are important and the National Academy of Sciences urges both the governments of the United States and Canada to use them. The Dietary Reference from 2002 is known to contain the opinion of NAS on the amount of trans fats that a person should consume. Their recommendation is based upon two important factors. The first factor is that trans fats are not considered to be essential acids and they do not provide any health benefits at all. The second very important factor is the fact that trans fats decrease the amount of HDL cholesterol levels in the body. HDL cholesterol is considered to be the good cholesterol. Because of this, a person with lower levels of HDL cholesterol is a lot more prone to develop coronary heart disease.
Numerous studies were conducted on the health benefits of trans fats and not even one of them proved that trans fats provided any health benefits at all. On the other hand, all of the studies showed that an increased consumption of trans fats increases the risk of coronary heart disease. Due to all of the mentioned the NAS is unable to determine just what is the safe level of consumption of trans fats.
However, the NAS did not recommend the exclusion of trans fats from the diet either. This is mainly because these fats can be found in many animal foods but in trace quantities. If a person should exclude these foods which contain trans fats, he or she would probably experience certain side effects and trigger a nutritional imbalance. This is why people should not exclude trans fats from their diets but should only consume them in trace quantities. Trans fats should provide less than 1% of total energy intake.
Many experts are still looking into the matter how exactly trans fats cause certain health problems. One of the theories is that humans are unable to metabolize trans fats due to the fact that lipase enzyme works only on the cis configuration. Scientists are familiar with the way in which trans fats increase the risk of coronary disease but why trans fats may trigger diabetes still remains unknown.
In order for the increased risk of coronary heart disease to be measured, experts have come up with two tests. Both of these are blood tests. The first one is called a cholesterol ration and it compares the levels of bad cholesterol or LDL to good cholesterol or HDL. Unlike saturated fats, trans fats increase the levels of LDL cholesterol and significantly decrease the levels of HDL cholesterol. The second test is called C-reactive protein.
Apart from the increased risk of coronary heart disease, there are some other effects which trans fats cause.
A certain study from 2003 showed that intake of both trans and saturated fats promoted the development of Alzheimer’s disease. However, there was no strong proof that backed this study.
When cancer is considered, there is still no scientific consensus that consumption of trans fats increases the risk of any malignant tumor. There was one study which claimed that the consumption of trans fats increased the risk of prostate cancer but this theory was not confirmed when a larger study was performed.
The majority of experts strongly believe that there is a connection between type 2 diabetes and consumption of trans fats but there is still no strong proof.
When obesity is considered, it is clear that those who consume more trans fats are more prone to becoming obese. Despite the similar caloric intake, trans fats increase weight gain and abdominal fat. A study proved that monkeys on a trans diet gained 7.2% of their body weight while monkeys on a mono-unsaturated diet gained only 1.8% of their body weight.
Liver dysfunction is another concern connected with trans fats due to the fact that tans fats are metabolized differently by the liver. A certain study also claims that the intake of trans fats increases the risk of infertility in women.
Finally, one study in Spain which included more than 12,000 people proved that the risk of depression is greater by 48% in those who are on a trans fat diet than in others.