Fats: Friend or Foe?

The Good: Fats, scientifically identified as lipids, are the most energy-dense nutrients available for the body. Fat is employed by all parts of the body other than brain, nerve and red blood cells to generate energy. At the same time, fats also insulate the body and cushions internal organs from damage.

The Bad: Diets composed of significant amounts of fat are correlated with higher incidences of heart disease and some types of cancer. At the moment, coronary heart disease is the number one killer in North America (is it any wonder with all the fast food chains around every corner?). According to the Canadian Health Guide, `the Canadian diet should include no more than 30 percent of energy as fat and no more than 10 percent as saturated fat.

An Overview of Fatty Acids

Fatty Acids are the monomers (building blocks) of fat. Put simply, they are composed of long carbon chains with hydrogen molecules attach. Fats are identified by the different structures of their fatty acid chain that vary with molecular bonding and the number of hydrogen attached. These distinctions account for the different effects that various fats may have.

Saturated Fats are literally saturated with hydrogen molecules (they carry the maximum number possible). This type of fat is typically found in animal fats, dairy products, and topical oils. They are linked to a rise in serum cholesterol (in particular LDL, or Low Density Lipoprotein), which can lead to deposits in blood vessels.

Trans Fats have been dubbed the worse type of fat, with ten times the potent effects of saturated fats in fact! Trans Fats normally appear in hydrogenated fats (ex. fast food), pastries, cookies and margarines. Like saturated fats, trans fats are responsible for raising LDL but at the same time lowering good cholesterol, HDL (High Density Lipoprotein).

Mono-unsaturated Fats are found in commonly found in olive oil, canola oil, peanuts and avocados. This type of fat has one or two hydrogen molecules missing depending on the number of double bonds in the fatty acid carbon chain. This is one of the `preferred fats`, in that it helps lower LDL in the blood without compromising HDL levels. HDL helps the body by carrying cholesterol out of the bloodstream. Research also indicates that HDL can be increased through exercise.

Polyunsaturated Fats can be found in sunflower, corn, flaxseed, sesame, and soybean. Polyunsaturated fatty acids have a number of bends in its carbon chain from double bonds and have many hydrogen molecules missing. Polyunsaturated fats decrease both LDL and HDL in the body.

Essential Fats include linoleic and linolenic acids that ensure normal growth and health. Essential Fats cannot be synthesized within the body, thus must be consumed in your diet. A lack of these fats may result in vulnerability to infection, dermatitis, abnormal growth, and reduced reproductive ability. Essential fats can be found in meats, fish, poultry, vegetables and vegetable oils.

Triglycerides are the primary form of fat used for transport and storage in the body. Triglycerides (for those interested to know), are composed of three fatty acid chains connected to a glycerol molecule.

Minimizing Fat Intake

Contrary to what some people may think, fat is a vital component of your body. Thus, it is important to make informed decisions when incorporating fats into your diet, especially selecting foods low in saturated fats and rich in mono and polyunsaturated fats. Such choices will have long term benefits by reducing the risk of coronary heart disease and blood cholesterol. Here are some more helpful food tips:

  • Choose low-fat dairy products, sauces and dressings
  • Eat leaner meats such as poultry more often than beef and pork
  • Prepare foods with little or, better yet, no fat
  • Reduce those high fat snacks and desserts!

Related Pages:

Nutrition: Canada's Food Guide - Use Canada's Food Guide to create a balanced, nutritional eating plan.

Nutritional Info: Vitamins - Understand the critical role of vitamins in your health and fitness.

Body Composition and BMI - Learn how to manage (or reach) your ideal body composition.