In the last blog we discussed saturated fats.  We will continue to discuss fatty acids with monounsaturated fats.

II. Monounsaturated Fat

Monounsaturated fatty acids are liquids at room temperature and semisolid or solid when refrigerated.  Foods containing monounsaturated fats reduce low-density lipoprotein (LDL, the “bad”) cholesterol, while possibly increasing high-density lipoprotein (HDL, the “good”) cholesterol.

There are two types of monounsaturated fatty acids.

1. Palmioleic acid (Omega 7) is found mainly in dairy foods.

The good: Recent evidence shows that palmioleic acid reduces the incidence of heart disease since it decreases blood cholesterol.  It also lowers blood glucose levels thereby reducing the risk of type II diabetes.  Milk is also a good source of protein.

The bad: I read over and over “Only calves should drink cow’s milk.”  The negative aspects of dairy consumption are starting to out-number the positive.  Dairy products contain a lot of saturated fat if you don’t choose “fat-free” products.  Allergies and lactose intolerance are increasingly more common.  Because of consumer awareness more people are avoiding mass produced milk and selecting hormone and pesticide-free dairy products. It is proven that sebaceous glands secrete more oil after consumption of all (even fat-free) dairy products.  The response to dairy products mimics the reaction that occurs during puberty when we have increased oil production, which leads to acne.

2. Oleic acid (Omega 9) is what we commonly think of when referring to a monounsaturated fatty acid since olive oil (an omega 9) is becoming more commonly used in American food.

Various foods contain oleic acid.  The richest and most common source of oleic acid is the olive and olive oil. Avocados, canola oil, nuts and seeds all contain oleic acid in varying amounts.

The good: The beneficial health effects of olive oil are due to both its high content of monounsaturated fatty acids and its high content of antioxidative substances.  Studies have shown that olive oil offers protection against heart disease by controlling LDL cholesterol levels while raising HDL levels. Olive oil is the cornerstone of the Mediterranean diet.

The bad: There is nothing really bad about fresh olive oil.  However, olive oil can oxidize easily. Olive oil, as any other product containing antioxidants and/or oil is vulnerable to oxidation when it is exposed to light and oxygen.  It must always be stored in an airtight, dark bottle and kept in a cool environment.  Oxidized oils are dangerous to your health because they oxidize the cholesterol in your body and can also deplete our body’s antioxidant supply.  Oxidation destroys antioxidants.

When I started the omega-3 section of this blog I quickly realized I could not write about why we needed omega-3 oils if I didn’t know details about the other oils we consume.  While researching the subject I found myself wading in the minutiae of fatty acid composition.  I really did not want to learn as much as I did about this subject.  However, like anything else, the more I learned the more interested I became.  I can now say that this is a fascinating subject!

Once again, before we get into the details of omega-3 I think we should organize the fats we consume into their three main categories.

As I mentioned in a previous blog, understanding oils is confusing because there are so many names given to the different oils.  Various literature will make reference to “double bonds” and “saturated with hydrogen.”  Don’t let these descriptions and/or terminology confuse you.

Saturated, monounsaturated and polyunsaturated are three basic categories of fat. I am not including trans fat in the categorization.  As you recall, trans fats are hydrogenated omega-6 oils.  They are not considered a food group since the body cannot use them for energy.  Its only purpose is to provide a cheap source of fat in packaged and fast food.

I. Saturated Fat

Saturated Fatty Acids are chains of fatty molecules packed or saturated with hydrogen atoms.  Saturating, or packing, chains of oils with hydrogen, makes the oil very dense and stiff. They are solid at room temperature and tend to solidify inside our arteries if more than we need for cell function is consumed.

Most of the saturated fat we consume comes from animals and milk which we make into butter and cream.  Egg yolks have nearly been banned from most people’s diets since they represent the epitome of the saturated fat which causes high cholesterol in our blood.  The saturated fat in eggs doesn’t raise our cholesterol  as much as we once thought.  Eggs are also packed with nutrients and a great source of low calorie protein.

Some plant oils, such as palm, coconut, and cottonseed, also contain a large amount of saturated fat.  American companies who used these oils in popcorn and other snack foods have stopped using them since they received such bad press.  However, scientists are taking another look at palm and coconut oil since there is evidence that these plants also have nutritional value that may outweigh the negative effects of the saturated fat they contain.

The good: Saturated fat is necessary for brain function and is an integral part of a well-functioning immune system.  Saturated fat is also an important source of energy.

The bad: Saturated fat is detrimental to our health when it is the only fat we include in our diet.  The type of fat we consume should be varied since each fat serves a particular purpose.  No fat is 100% bad except trans fat.  Saturated fat can cause plaque inside our arteries, which can lead to a decreased blood flow to our heart, causing a heart attack.  However, this information is a bit misleading since in the past we have confused and interchanged the terms “saturated fat” with “trans fat.”