Figure Athlete - Fats: The Good, the Bad, and the Ugly

Fats: The Good, the Bad, and the Ugly
by Marie Spano, MS, RD, FISSN, CSCS

Are you confused about fat?

You know you have to eat some fat, but you're sick of olive oil and are unsure about any substitutes. One minute polyunsaturated fats are on the good list, and the next minute, they're bad. You thought Tilapia was healthy, and then the media slammed it thanks to one research study.

As always, Figure Athlete's here to clear things up. Consider this your definitive guide to fats: The good, the bad, and everything in between.

Fats are made up of many fatty acids, the same way proteins are made up of varying blends of amino acids. Fatty acids are grouped according to their chemical structure and fit into two main categories: unsaturated and saturated. However, every fat typically has a mixture of these fatty acids.

Olive oil, for instance, isn't 100% monounsaturated fat — it actually has about 9% saturated fatty acids (stick it in the refrigerator and you'll see the saturated part turn solid within a few days). For our intents and purposes, however, it's easiest to examine fats grouped into the main categories of fatty acids that they contain. We'll add an extra category for chemically altered fatty acids, as well.

Unsaturated fats are linked to lower LDL cholesterol (bad cholesterol) and are considered heart healthy. There are two types of unsaturated fats: monounsaturated and polyunsaturated.

Monounsaturated Fats

Monounsaturated fatty acids are often reported as being healthier than polyunsaturated fats, but it really depends on the specific mono- or poly- that you're comparing. Keep in mind that there are many different fatty acids that fit within each category. When eaten in moderation and replacing saturated fats or man-made trans fats, monounsaturated fats are considered healthy.

Olive oil, which is widely touted as heart healthy, is rich in the monounsaturated oleic acid. Diets rich in olive oil are not only linked to heart health, but have also been shown to reduce morbidity.

Nuts and nut butters are also good sources of oleic fatty acid. Other oils high in monounsaturated fats include canola oil, peanut oil, sunflower oil, and sesame oil.

Though monounsaturated fats are healthy, each one varies according to its heat point and uses. The lower the heat point of an oil, the less it can stand high temperatures. Therefore, an oil with a low heat point should not be used for deep fat frying.

Olive oil has the lowest heat point, followed by sesame, peanut, corn, canola, soybean, sunflower and safflower oils. Here's a breakdown of the various uses of certain monounsaturated oils:

• Olive oil: Sautéing, pesto, salad dressing.
• Peanut oil: Light sautéing, sauces, salad dressing.
• Canola oil: Baking, sautéing, stir-fry, dressing.
• Almond oil: Sautéing, frying.
• Avocado oil: Sautéing, frying.

Polyunsaturated Fats

Polyunsaturated fats are ones that have two or more double bonds. Two kinds of polyunsaturated fatty acids are actually essential to us — we must consume them. These are linoleic acid and linolenic acid.

Linoleic acid is contained in a number of foods and oils, and is therefore consumed in good quantities in Western diets. Some readily available oils containing this fatty acid include safflower, sunflower, cottonseed, corn, soybean, canola, sesame, grape seed oil and more. As you can see, chances are good that you're currently consuming a sufficient amount of this kind of fat.

In fact, many scientists believe that we Americans consume entirely too much of this fatty acid, especially when compared to the amounts of linolenic acid included in our diets. You see, consuming an excess of this omega 6 fat in conjunction with sub-par amounts of omega 3 fatty acids found in linolenic acid has been shown to increase inflammation and certain chronic diseases.

Alpha linolenic acid (ALA) is found in certain plant sources such as chia, flaxseeds and flaxseed oil, walnuts, soybean oil and canola oil. If you don't consume enough ALA, you can meet your omega 3 needs by eating fatty fish, which contains DHA and EPA (ALA is broken down in the body to these two fats), or supplementing with a quality fish oil.

Being mindful of your omega 3 intake is absolutely crucial to ensure optimum health through proper fatty acid ratios, especially since many oils do contain both fatty acids but are higher in omega 6 fats. Omega 3s are linked to decreased inflammation, decreased risk of certain chronic diseases such as heart disease, decreased blood pressure and cholesterol, and improved mood.

If you choose to supplement, take up to 2 grams of omega 3s per day. (Editor's note: Biotest Flameout[link to online store] has the highest concentration of omega 3 fatty acids available in capsule form).

Let's take a look at the breakdown of various uses for the polyunsaturated group:

• Walnut oil: Baking, sautéing, or drizzle this on your salads for a little variety.
• Flaxseed oil: Salad dressings, salsa, dips. Do not use for sautéing or cooking with high heat.
• Safflower oil: Sautéing, frying, baking.
• Sunflower oil: Sautéing,frying.
• Corn oil: Light sautéing (low heat), sauces.

Saturated fats have gotten a bad rap thanks to the fact that many varieties have been shown to raise LDL levels (bad cholesterol). But it isn't all black and white with these fats due to the fact that each saturated fat is different.

Some saturated fatty acids don't have any negative effects on cholesterol — like in the case of stearic acid, the saturated fat contained in bitter chocolate.

There are two distinctly different types of trans fats:

1. Vaccenic Acid

This fatty acid is naturally found in lamb, dairy, cow and deer. It's converted to CLA (conjugated linoleic acid) in the body, and carries some health benefits when it comes to weight control, bodyfat reduction, and has even been shown to be anticarcinogenic.

2. Man-Made Trans Fats

These are chemically altered fats that include partially and fully hydrogenated oils, fractioned oils, and interesterified fats. Each of these has slightly different structures and effects the body in different ways; let's take a look at these differences.

In the early 1900's, chemists started adding Hydrogen gas to liquid oils under high temperatures to create partially hydrogenated oils. This is how Crisco (crystallized cottonseed oil) was born.

This altered fat was cheaper than butter, so its use grew in popularity when butter was rationed in the 1940s. Besides being relatively inexpensive to produce, it has a high melting point making it fabulous for frying, it doesn't go rancid like other oils, and it's vegan friendly — all of which have increased its popularity to this day.

The chemical structure of this fat is important. Trans fats stack neatly on top of each other, making the fat solid both in food and in your body. A diet high in trans and/or saturated fats can alter the fluidity of cell membranes, making them more solid. This in turn can alter the receptor sites on the cell membrane (where insulin binds, for instance).

Some health effects of man-made trans fats include:

• Increased LDL (bad choleserol)
• Increased Triglycerides
• Decreased HDL (good cholesterol)
• Increased insulin resistance
• Increased risk of cardiovascular disease
• Interferes with essential fatty acid metabolism
• May increase abdominal fat
• Increases proinflammatory cytokine production
• Alters cell membrane fluidity

Health Verdict: If it's not yet obvious, let's make this crystal clear: Avoid partially hydrogenated oils and anything with these in them!

Sure it's spreadable, but that's about the only positive thing about it!

One final note: Any product with less than 0.5 grams of trans fat per serving may list its trans fat content as "0" on its food label, but you can always scrutinize the ingredient list to be on the safe side.

Fully hydrogenated oils undergo the same chemical reaction as partially hydrogenated oils, but they have fewer trans bonds (bonds where the hydrogen molecules are on opposite sides). With less trans fatty acids, fully hydrogenated oils are considered less harmful than partially hydrogenated oils.

Full hydrogenation actually increases the amount of saturated fats, but most of this is in the form of stearic acid (a saturated fat that doesn't raise LDL cholesterol levels). In fact, in an effort to reduce the amounts of trans fats consumed by the public, companies producing shortening have changed their formulations so that their products are now composed largely of fully hydrogenated oils.

Health Verdict: Fully hydrogenated oils maybe less harmful than partially hydrogenated oils, but there's little to no research examining their health effects. In either scenario, these will in no way be beneficial to your health, so avoid them whenever possible.

Fractionated oils are found in chocolate coating on bars and in other processed products.

Fractionated oils are just that — fractions of fats. The oil (often palm or coconut oil) is heated, then cooled, and the fractions are separated.

The thicker fractions are then used in margarines, shortenings, and various confectionary products; they keep the chocolate coating from melting at room temperature. Fractionated oils are more saturated than the initial oil used prior to the fractionation process.

Health Verdict: Fractionated oils are probably less harmful than partially hydrogenated oils. They're also typically used in small amounts (think of the chocolate coating on a cereal bar), so they rarely produce any sort of a tangible effect on the health.

Interesterified fats have been chemically or enzymatically rearranged. Think of a ladder with its rungs rearranged or removed. Doing this to a fat alters its texture, making it suitable for certain nutrition applications.

There have only been a few studies examining the potential health effects of interesterified fats. So far, we know that these may:

• Increase blood glucose
• Decrease LDL
• Increased HDL

How will you be able to spot these fats? Look for "interesterified fats" or "fully hydrogenated oil" on the food label. In restaurants, it's much harder to detect food prepared with interesterified fats; you'd have to find out if they use shortening or any hard fat versus liquid oil. You could ask restaurant workers, but most will either not know, or not care.

The American Heart Association states that the safety profile of interesterified oils is not well understood and that additional studies are needed. While they're not adamantly opposed to this type of fat, its long-term effects will remain unclear until further research.

Health Verdict: Minimize these in your diet until we know more.

As with other foods, you should aim to consume a variety of fatty acids. Try switching up your regular olive oil and toss your salad with a little flaxseed oil, instead. Brush almost-done chicken breasts lightly with peanut oil; consume different nuts, seeds, and various types of fatty fish.

The more you switch up the fats you eat, the more likely you are to consume a mixture of fatty acids — and the healthier you'll be.

Marie Spano is a leading authority on translating the latest nutrition and exercise science research into real life applications. Ms. Spano has also helped Olympic athletes, NFL-bound athletes, and Fortune 500 executives enhance their health and performance through sound nutrition practices. For more information, please visit www.MarieSpano.com.

Am J Clin Nutr 1981;34:2307-18.

Am J Clin Nutr 1991;34:2307-2318.

Am J Clin Nutr 2007;85(3):662-77.

Diabetes Care 2002;25:1283-8.

Circulation 2007;115(14):1858-65.

Am J Pub Health 1995;85 (3): 411—412

www.CDC.gov/HeartDisease

N Eng J Med 2006;354(15):1601-13

Nutr Res Rev. 2000 Dec;13(2):185-214.

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