Tuesday, October 2, 2018

Hydrogenation and Transformation


You might have heard that two weeks ago, September 17th 2018, Canada officially banned trans fats (yay!!). This raised many questions on what are trans fats and why are they banned. And how should we feel about this.

What are Trans Fats?
Before answering this question, let’s dive back into basic chemistry. Butter is a saturated fat, which means that the fatty acid chain is FULL of hydrogens (saturated), which makes the chain straight and compact. The chains pile up nicely, making butter hard.

Oils are what we called unsaturated fats. Their fatty acid chains are NOT full of hydrogens, so the chains have kinks in them, making them more difficult to stack. The chains don’t pile up as nicely, so oil is liquid.

Hydrogenation is the process of chemically shooting hydrogens into an unsaturated fat to saturate it. This is frequently done in the food industry because it’s a cheaper way to have harder fats used for better texture and a much longer shelf life. The food industry loves long shelf lives. The classic example: replacing butter with margarine made of hydrogenated oils.

Theoretically, this transformation would make oil turn into butter. However, the reaction done in the lab does not fully represent what is found in nature. It is very difficult to fully saturate a fatty acid chain, so you inevitably get partially hydrogenated fats, which are partly unsaturated while still having a semi-soft texture and longer shelf life as desired. The bonds created through this reaction are in the ‘’trans’’ formation, as opposed to being in the ‘’cis’’ formation found in nature.


Fully hydrogenated fats do exist and are also called hydrogenated oils. They are harder than trans fats and do not have the characteristic ‘’trans’’ bonds that partially hydrogenated fats have, so they do not lead to the health risks associated with trans fats.

Where Can We Find These Trans Fats?
Trans fats became extremely popular in the food industry in the 1950s, with Crisco shortening as their leader. They can be found in a plethora of transformed foods, such as commercial baked goods (cookies, pastries, doughnuts, muffins, frosting), fried foods (french fries, fried chicken, chips) and many snack foods (crackers, microwave popcorn). Over the years, as people became increasingly aware of the negative effects of trans fats, foods with labels reduced or avoided their use. However, they are still commonly found in foods with no labels, such as a muffin at Tim Horton’s or a cheeseburger and fries at McDonald’s.

Other Names Used to Identify Trans Fats
  • Partially hydrogenated oils
  • Hydrogenated oils
  • Shortening
  • Mono- and diglycerides
  • Anything deep fried

 Trans fats are also naturally found in low levels in dairy products. However, no adverse health effects were found to be related to these trans fats.

What Are the Health Risks of Eating Trans Fats?
If I had to name one thing that is most destructive for your body that you can find in your food, it would be trans fats. An overwhelming amount of data exists on how harmful they are, and yet, it took decades to finally get rid of it.

The biggest issue with trans fats is that they are extremely inflammatory, and inflammation is the first step to every chronic disease, like type 2 diabetes or cardiovascular disease, for example. Trans fats raise LDL-cholesterol levels, more specifically the small dense LDL particles. These are especially damaging to your blood vessels (as seen in the cholesterol article, found here). Trans fats also lower the protective HDL particles that clean up your arteries.

In 2002, the Institute of Medicine stated that there is absolutely no safe level of trans fats in the diet; any increase in intake increases the cardiovascular disease risk.

So Now What?
After a decade of struggling to get trans fats out of our food, they are officially banned. Industries have two years to use up their stock, change their recipes and replace them. However, for the time being, they can still be found in many transformed foods. To avoid them, here are two things that you can do:

1) Read the nutrition facts table. Food labeled as ‘’trans fat free’’ must have less than 0.5g of trans fat per serving. Note that this means that if there are 0.4g of trans fats in your chips, the package can say 0g per serving, and if you eat two servings, then you just ate 0.8g of trans fats, while any amount is harmful. But the package still says zero.

2) Read the ingredients list. Scan the ingredients list for any of the synonyms listed above. If you find a food item with any of these ingredients, leave it at the grocery store.



In two years, we won’t need to worry about trans fats anymore. Hopefully the US FDA will follow in our food steps.

We’ll just have to wait to see what the market will invent to replace trans fats, and probably need to avoid whatever they come up with as well.

References


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