Friday Reading Report: Fat City

This week, my studying is all about fats.  I think my head might be fatter as a result.  Here’s what I’ve learned, plus some other comments.

In food, fat comes mostly in the form of triglycerides.  The more saturated the triglyceride, the more solid the fat at room temperature.  Saturation, in this context, has to do with the chemical structure of the fat molecules.  If chemistry was a long time ago for you, like it was for me, let me remind you that different atoms have the ability to bond with different numbers of other atoms.  In the case of carbon, it can bond with more than one other atom, or it can bond with, say, another carbon atom more than once.  When the carbon atoms in triglycerides form double bonds, the molecules don’t have as many available bonds for hydrogen atoms and are thus less “saturated” with hydrogen, less solid at room temperature, and, usually, better for us.  One double bond among a triglyceride’s carbon atoms makes it monounsaturated.  More makes it polyunsaturated.

The interesting part is that most fats are mixtures of many triglycerides.  We just categorize them by the kind they contain the most of.  Among the oils we categorize as monounsaturated, we have olive, canola, peanut, and safflower.  Of those, canola has the least saturated fatty acids and peanut oil has the most.  This study and others like it suggest that canola oil is a good choice for reducing cholesterol levels.

However, there are some caveats.  The best kind of oil to use depends heavily on the use.  Olive oil breaks down at high temperatures.  Peanut oil doesn’t.  If the goal is deep-frying, olive oil is a bad choice.  Most baking does better with more saturated forms of fats.  I’m pretty sure that canola oil on toast is not going to be the next craze when we are done with avocado toast (although why would we give up our avocados?).

Additionally, the reducing effects of using monounsaturated and polyunsaturated fats are compared to using saturated fats.  In other words, it is still possible to have too high a level of cholesterol while consuming only the “healthier” fats.

Finally, all the categories of fats have the same 9 calories per gram, regardless of saturation level.  Fats of all kinds are more calorie dense than protein or carbohydrates and anyone wanting to reduce overall calorie intake might want to take a look at cutting fat to remove unneeded calories.  (Leaving aside the whole keto thing, which I have discussed elsewhere.)

As with all nutrition information, it is important to consider the sources and also to consider the effects of different diets in our own bodies.  Some of us do better on different kinds of diets than others.  Information is only the start; we need to apply judgment as we choose what to eat.