A Primer on Dietary Fats – Part 1

For the past 30 years or so, ever since people started talking about cholesterol and heart disease, there has been a combination of concern and confusion over the topic of dietary fats in the diet.  In this article, I want to take a look at some of the topics involved to see if I can help to clear up some of the confusion.

Today I want to look at some general issues, including the major categories of dietary fats, the difference between cholesterol and triglycerides, and then look briefly at the impact of dietary cholesterol on blood cholesterol levels.  On Friday, in Part 2, I’ll look in some detail at the different types of dietary triglycerides and address some of the current controversy over their effects on health.

 

Triglycerides, Cholesterol and Everything Else

While people tend to throw around the term dietary fat somewhat loosely, the fact is that not all of the fat that we consume on a daily basis is the same.  And here I’m not talking about saturated vs. unsaturated fats.  Quite in fact, dietary fats (more generally known as lipids) come in distinct chemical types.

Now, the primary two that folks eat on a day to day basis are triglycerides (TGs) and dietary cholesterol with dietary triglyceride contributing the bulk (over 90% of the total) of the dietary fat that we consume on a day to day basis.

However, there is also a small amount of lipid that come from sources such as various phospholipids and other fat based compounds; since they tend to make up a very small percentage of the total daily fat intake, I’m not going to spend any time discussing them.

Rather, I want to focus primarily on dietary triglyceride and cholesterol.

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