Fats are Lipids

There are different categories of lipids:

  • Triglycerides
  • Oils
  • Cholesterol

These compounds are grouped together because of their structural and physical similarities.  All lipids are insoluble in water, are oily to the touch, and together with carbohydrates and proteins constitute the principal structural material of the body.

Triglycerides contain fatty acids which differ in their structure, size and shape, which influences their use and effects on the body.  Lipids are further separated into fats and oils based on their physical properties at room temperature: fats are solid at room temperature; oils are liquid at room temperature.

The white layering in this slab of pork belly is an example of triglycerides, solid lipids.

The white layering in this slab of pork belly is an example of triglycerides, solid lipids.

Olive oil is an example of an unsaturated fat.

Olive oil is an example of an unsaturated fat. It is liquid at room temperature.

Cholesterol is a lipid that combines with protein to form hormones. Hormones are chemical messengers that tell the body tissues or cells what to do and when to do it. Three basic types of cholesterol are high-density lipoprotein (HDL), low-density lipoprotein (LDL), and very-low-density liproprotein (VLDL). Cholesterol’s impact on health will be discussed later.
FYI: Fats provide 9 calories per gram.  Therefore, the 12 grams of fat in a regular-sized Snickers bar provides 108 fat calories!