Before continuing the discussion of the negative impact of consuming trans fats any further, let us talk about naturally occurring sources that are significantly less toxic. We can find some in the chloroplasts of diverse leaves (trans-3-hexadecenoic acid) and in the oils extracted from rare grains (eleostearic acid in bitter melon and in tung). However, it is mostly found in the rumen of ruminants (e.g. cows, sheep, goats).
The numerous bacteria of rumen have very unique properties such as the ability to create fatty acids with an uneven number of carbon atoms: e.g. margaric acid with 17 and pentadecylic acid with 15. It is this last one that allows us to identify consumers of dairy products in the eventuality that they need to exclude these from their diet!
Some rumen bacteria produce fatty acids that are naturally trans, a very rare phenomenon in nature, where the vast majority of unsaturated fatty acids are of the cis configuration. Trans-9-octadecenoic acid (or elaidic acid) and trans-11-octadecenoic (or trans-vaccenic acid) are examples of this. CLA (conjugated linoleic acid) is an especially interesting example and appears to have interesting properties for human health, promoting the development of lean body mass at the expense of adipose tissue, as confirmed by several trustworthy scientific studies.
The negative effects of trans fats, like most rules in biology, have some exceptions. However, generally speaking, these chemical poisons have some scary side effects, either when they are generated by the food industry, or by ill-advised cooks. They have been widely studied and the results are published in the compilation of articles in my conference “Danger of Trans Fatty Acids” (see the review Conferences/Unsaturated Fatty Acids on my website www.gmouton.com)
So, in no particular order, let’s list them: cardiovascular diseases (coronary artery disease, myocardial infarction, arteriosclerosis, sudden cardiac death, inflammation of the vascular system, endothelial dysfunction); type II diabetes (insulin resistance, increased fasting glucose); cancer (non-Hodgkin lymphoma, prostate cancer, colon cancer, rectal cancer); depression; gall stones; ovarian dysfunction…. Undoubtedly, this is not an exhaustive list, as future research will surely demonstrate.
Implementing measures to reduce trans fat consumption gives rise to some spectacular effects: the industrial production of these trans fatty acids has been reduced in Denmark – a country at the forefront of the fight - from 6 grams per inhabitant per day in 1976 to 1 gram in 1996. Concomitantly, deaths from coronary diseases have fallen by 50%, figures that speak for themselves. Similar data are available for Finland and more recently for Poland.
Your levels of trans fatty acids can easily be measured via a blood test: more and more laboratories offer these tests. They are helpful in targeting patients who need incisive advice to reduce their consumption.
Practically, you should ban all products that include “partially hydrogenated vegetable oils – or vegetable fats” in their ingredients list: they can destroy your health.