Fat, Good and Bad Fatty Acids

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[edit] Fat, good and bad fatty acids

Fat has been looked at with caution, and it has often been perceived as the villain. There has been a perception, that fat is the "bad guy", the enemy that is responsible for obesity, heart disease, clogged arteries and other ailments. A lot of products line the supermarket shelves and proclaim that they are "no-fat" or "low-fat" or "cholesterol-free".

First of all it is necessary to realize that there are fats that are essential and vital for us. As mentioned before, our bodies need to have essential fatty acids, as it cannot make them out of other nutrients. There are fats, which are beneficial, and a small amount in our food plays a role to slow down the entry of carbohydrates into the bloodstream.

It also sends hormonal signals to the brain: we feel satiated and no longer hungry. As a sensible rule of thumb we should not exceed 30% of our caloric intake from fat !

A group of "good" fats are called monounsaturated fats. They occur in olives or in olive oil, avocados, almonds and macadamia nuts.

Next there is the group of the poyunsaturated fats, which are divided into two groups:

1. Those containing omega-3 fatty acids, a "good fat" source occuring in foods like salmon, mackerel, sardines, tuna or fish oil.

2. Then there is the sub-group containing omega-6 fatty acids, occurring in corn oil, sesame oil, and grapeseed oil. They need to be balanced by omega-3-fatty acids or they could lead to inflammatory conditions like arthritis (Ref.7,262).

It is the saturated fats, that are the "bad" fats. They occur in animal fats like butter, lard, and dairy fat, but they are also found in tropical oils (palm oil or coconut oil). The follwoing table was summarized by me from data of Ref. 3, p. 108-109).

Fat, the good, the bad and the ugly
Type of fat:		Comments:
"good":	fats and omega-3-fatty acids	good because they are the only essential fatty acid that the body cannot make: found in salmon, mackerel, sardines, tuna or fish oil.
	monounsaturated fatty acids	good, because not prone to oxidizing and no effect on insulin: found in olives, olive oil, avocados, almonds and macadamia nuts
"neutral":	omega-6-fatty acids	only neutral, if balanced with omega-3-fatty acids: corn oil,sesame oil, and grapeseed oil
"bad":	saturated fats	raises LDL (=bad) cholesterol, found in animal fats like butter, lard, dairy fat (cheese, ice cream etc.), but also found in tropical oils (palm oil and coconut oil)
"the ugly":	hydrogenated fat or partially hydrogenated fat, trans fatty acids, "pure vegetable shortening"	good for long shelf-life of cookies, bad for your heart. Increases LDL and lowers HDL cholesterol. Found in margarine, deep fried foods, lard, vegetable shortening

Unfortunately there is another group that is the worst of them all, those fats which contain trans fatty acids. They are called trans fats and are like the new bad kid on the block: before the 20 th century they did not exist.

They were developed in an effort to transform liquid oils into a spreadable fat. This way margarine was created. Also, the shelf life of products containing trans fats is longer. This way, butter, which is an animal fat that forms the bad cholesterol, plugs up arteries , and leads to heart attacks and strokes was replaced. It certainly was cheaper than the expensive butter,also it did not turn rancid like butter, but the trans fats in the margarine are even worse than the fat in butter.Trans fats raise the bad cholesterol and at the same time lower the good cholesterol, which is a double whammy to wreak havoc with our health! Despite all the claims that some margarines are lower in trans fat than others and are labelled "heart healthy", be aware that trans fats at this point don't have to be listed on food labels. If you read the word "hydrogenated", it means "bad trans fats"!Foods with high trans fat levels are best avoided altogether: deep fried foods like french fries, chips or nachos are on this list. Cookies, pies and snack foods are also on the "not wanted" list. A wide range of commercial bakery products are prepared with shortening. The harmless sounding term "pure vegetable shortening" is a trans fat and not harmless at all!

There are grandiose promises that fat absorption would be possible with Chitosan. This is an extract derived from the shells of shrimp and other sea crustaceans. However, objective testing of these claims as referenced in Ref.8 below and many other medical papers could not confirm this claim. While it is not harmless except to those with allergies against seafood, it is a waste of money. There are no shortcuts that would replace the combination of watching what you eat and exercise.

The do's and don'ts about fat intake

To make sensible and healthy choices you do not need a degree in nutrition. All you have to do is:

1. Read the labels and ingredient lists. Potato chips suddenly don't look so good: 3 Grams of trans fats per bag clogging your arteries.

2. Avoid products, which contain hydrogenated or partially hydrogenated fats (congratulations to the mayor of New York who publicized this).

3. Eat one food per day, which contains omega-3 fats (if you do not like fish, take two capsules of fish oil).

4. Use some monounsaturated fats like olive oil.

5. Do not exceed the 30% mark of fat in your daily caloric consumption.

With these simple guidelines, fat will be your nutritional ally and not an enemy.

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References:

1. B. Sears: "The age-free zone".Regan Books, Harper Collins, 2000. Also see Dr. Sears' site.

2. B. Sears: "Zone perfect meals in minutes". Regan Books, Harper Also see Dr. Sears' site.

3. B.J. Wilcox, D.C. Willcox and M. Suzuki: "The Okinawa Program." Clarkson Potter,2001, N.Y., U.S.A.

4. E.L. Rossi: The psychobiology of mind-body healing. Norton &Co., 1986, N.Y., U.S.A.

5. Vitamins and Foods. Audio-Digest Family Practice Vol 49, Issue 29, Aug.7, 2001.

6. P.C. McGraw: Life strategies. 1999, Simon&Schuster Source, N.Y., U.S.A.

7. B. Sears: "The top 100 zone foods". Regan Books, Harper Collins, 2001. Also see Dr. Sears' site.

8. Journal of the American Dietetic Association, Volume 105 • Number 1 • January 2005, "Chitosan supplementation fat and absorption in men and women" by M D Gades and J S Stern, ScD (M. D. Gades is a graduate student and J. S. Stern is a distinguished professor of Nutrition and Internal Medicine, Department of Nutrition, University of California Davis, Davis, CA.)