Fat

Ahhhh fat.  It is what makes donuts and fried foods taste so good. It is what gives ice cream and chocolate that smooth, melt-in-your-mouth texture. It is a key ingredient in so many of the foods we enjoy, yet it can be so bad for us!

Why it’s Important

Many people think that any and all kinds of fat are bad. The truth is that we need fat to survive.

Functions of fat in our bodies:

• Produce hormones that spread signals to organs around our bodies. 
• Provide energy to our body; at rest our muscles burn fat, and well trained endurance athletes burn fat during endurance events.
• Aid in fat-soluble vitamin absorption.
• Maintain the quality and condition of our skin.
• Plays a key role in brain development and function.

Types of Fat and Their Effects

There are many types of fat in the average American diet. The chart below identifies sources of each of these types of fats. Though all fat supplies 9 calories/ gram, the different kinds of fat have different properties and have different effects on our bodies. The two main categories are saturated and unsaturated. They get their names from their chemical structures.

Saturated fats contain no double bonds in their structure (they’re saturated with hydrogen atoms). Most saturated fats are in a solid state when at room temperature. Some examples are lard, butter, and other animal fats. Coconut oil is another source of saturated fat, but is more of a liquid at room temperature. The effects saturated fats have on our body are not to be desired. First, saturated fat intake increases the total triglyceride levels in one’s blood. Triglycerides are the droplets of fat circulating in one’s blood.  Second, saturated fat intake increases the levels of Low Density Lipoproteins (LDLs) in our blood. LDL is one type of cholesterol that circulates in our blood, and has been known as the “bad cholesterol. Both triglycerides and LDL cholesterol have the potential to damage the blood vessels they travel through, which can ultimately cause hardening of the arteries, or Atherosclerosis. This is bad because the arteries become narrow and, should they become narrow enough, blood can clot in the vessel and block blood flow to the tissues downstream.  Atherosclerosis is a primary cause of stroke and heart attack.

Unsaturated fats contain at least one double bond in the structure. Most naturally occurring unsaturated fats are liquid at room temperature. They are found mostly in plant oils such as peanut oil, but also occur naturally in some plants and animals. Unlike saturated fats, there are three kinds of unsaturated fatty acids. They are monounsaturated fats, polyunsaturated fats, and trans fats.

Monounsaturated fats contain only one double bond, (mono=one).  Sources of monounsaturated oils are liquid at room temperature, but if chilled can become semi-solid. The effects that monounsaturated fats have on one’s body are actually desired. They decrease the LDL levels (bad cholesterol), and increase the High Density Lipoprotein (HDL) levels. HDL is deemed as the “good cholesterol” because it collects the LDL in the blood and destroys it, therefore decreasing your chances of damaged blood vessels.

Polyunsaturated fats contain two or more double bonds in their structure (poly=many).  Polyunsaturated fats also have desirable effects on our body. LDL cholesterol is decreased with polyunsaturated fat intake, thereby decreasing the chances of damaged blood vessels. There are two types of polyunsaturated fatty acids that are essential to our diet, meaning our bodies require them but cannot make them. These two essential fatty acids are omega 3 and omega 6 fatty acids.

Trans fatty acids are the final type of unsaturated fatty acids. They can have one or more double bonds like the other unsaturated fats, but its configuration is different than mono- or polyunsaturated fats. They are often found in solid forms, like Crisco shortening. Though some trans fats occur naturally, most are created synthetically and are used in processed foods to extend their shelf lives. It is not recommended to use or consume trans fats due to the harmful effects they have on our body. The effects of trans fats are opposite to those of monounsaturated fats; trans fats increase LDL, the “bad cholesterol”, and they decrease HDL, the “good cholesterol”. These two effects together increase the likelihood of damage occurring to blood vessel walls, which increases the risk for stroke and heart attack. 

Sources

 Requirement

The recommended fat intake for healthy, non-pregnant, non-lactating adults ranges from 20-25% of your total caloric intake. If you eat 2000 calories in a day, this means that you should be eating 400-500 calories from fat, or 44.5-55.5 grams of fat per day. Due to the hazardous effects of saturated fat, limit your intake to 7% of your daily caloric intake. Omega-3 and omega-6 essential fatty acids have different requirements for men and women; healthy non-pregnant or lactating adult females should consume 1.1 grams/day, and healthy adult men should consume 1.6 grams/day. Your intake does not have to be exact, but steer yourself toward eating the sources of these essential fatty acids. Trans fatty acid intake should be limited as much as possible, due to the harmful effects it has on our bodies.

When it comes to fat it is important to remember: Quality, not Quantity! What I mean by this is that we should eat fats that are good for us, but in limited amounts. Quality fats improve the taste of foods and have health benefits, but that also comes with the 9 calories per gram provided by fat. In practicing “Quality not Quantity” one can attain the amount of fat that our body requires while maintaining a neutral energy balance.

Meal Ideas                                               

• Use olive or canola oil for cooking
• Include walnuts on salad or cereal
• Eat cold water fish at least one night per week
• Replace real butter with Smart Balance; each serving contains 1.5 grams monounsaturated fat, 2.0 grams polyunsaturated fat, 300mg omega 3, only 1.5 grams saturated fat, and 0 grams trans fats.
• Eat lean meats to limit saturated fat intake
• Look for fat substitutes in cookie and muffin recipes to limit trans and saturated fat intake

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