Fats


Comments Off on Fats | Last Update: April 18, 2012

Fats Are Essential

Fats, known as lipids, include fats and oils.

Fats and oils occur in your body to keep it healthy.  Your skin and scalp have natural oils.  A layer of fat underneath your skin insulates your body from temperature extremes.  The fat in a women’s breasts protects the mammary glands from heat, cold and shock.  Fat in muscle tissue provides energy when muscles are active.

Your body stores fat two ways as intramuscular fat and subcutaneous fat.  The intramuscular fat is analogous to marbling found in a choice or prime steak.  It is fat your muscles use for energy when you are active.  Subcutaneous fat is your bodies fat reserve.  It is fat stored beneath your skin around your abdomen and thighs.  It is the same as the fat found around the edge of a steak or pork chop.

A pound of body fat, being about 85 percent fat and 15 percent water, can supply about 3,500 calories.  For a person who is fasting or eats very little during an illness, fat is one of the body’s main source of energy.  The other source is lean body tissue which can provide glucose for your brain and nerves.  That is one reason why you feel weak and wasted following a series illness.  Muscle atrophy causes weakness brought about by muscle protein being used for the production of glucose.  Your brain and nerves require glucose which can not be obtained from fat.

NOTE:  Your body can produce fat from carbohydrates and protein, but can not easily produce glucose from fat.

Fats Add Flavor

Most people love fried foods and other foods high in fat.  The compounds that give many foods there distinct flavor are found in the food’s fat.  These compounds are referred to as fat soluble.  Four essential vitamins, A, D, E and K are all soluble in fat.  But, what does it mean to be soluble in fat?

Fats and oils are molecules with a density lower than water.  That means fats weigh less than water for a given volume which is why fats separate and float on top of water and vinegar (which is mostly water).

Solid fats in meats and poultry float to the top when cooked in water and when cooled solidify so they can be easily removed.  When water and fat separate other compounds that are in the mixtures go with either the water or the fat.  When fats are removed from foods, like in lean ground beef, some of the flavors and vitamins are also removed sometimes in significant amounts.  That is why products like extra lean ground beef and skinless chicken taste different than their higher fat counterparts.

One of the benefits derived from eating low fat foods is the significant reduction in calories if the fat calories has not been replaced with an equal number of protein or carbohydrate calories.   One misconception resulting from the “low fat” craze of the past few decades is that “low fat” meant “low calories” when in fact that was not always the case.

When you compare the number of calories in a low fat food to its regular counterpart you may find, with a few exceptions, that they both have about the same number of calories.  Why?  Because the fat calories have been replaced with carbohydrate calories.  That is why it is important to read the nutritional labels on foods.  Calories are calories whether they come from protein, carbohydrates, fats or alcohol.  There are specific health concerns and benefits associated with each nutrient, but when it comes to weight maintenance it is the number of calories you eat per day that counts.  The following table illustrates how you can cut a significant number of calories from your diet by reducing the amount of fat you eat.

How fat adds Calories to foods

Food Calories
Pork chop with ½ inch of fat 260
Pork chop with fat trimmed 130
Baked potato, plain 90
Baked potato with 1 tablespoon each butter and sour cream 260
Whole milk 170
Skim milk 80

 

Triglycerides

Most people are familiar with the word triglyceride.

Blood triglyceride levels are checked by a routine blood test.  A low level is good, high level is bad.   Most fats are triglycerides. Triglcerides comes from food and is made by your body. People with high triglycerides often have high LDL cholesterol and a low HDL cholesterol level.  According to the American Heart Association:, triglyceride levels of:

Normal Less than 150mg/dl
Borderline high 150–199
May need treatment in some people 200–499
Very high 500 mg/dL or above

 

About 95 percent of fats are triglycerides.  The other two classifications are phospholipids and the sterols which includes cholesterol.  Fats are divided into four types:

  •     Saturated
  •     Unsaturated
  •     Polyunsaturated
  •     Monounsaturated

Essential fatty acids

Fats your body can not make are called essential and include the omega fatty acids. Omega-3 fatty acids reduce inflammation and assist neurological development. Omega-6 fatty acids aid blood clotting and fight infection which increases inflammation.

An American diet high in processed foods made from plant oils is high in omega-6 fatty acids. Some researchers have linked high levels of omega-6s fats to inflammatory diseases like asthma and arthritis. Omega-6 fats are in eggs, cereals, nuts, safflower, sunflower, corn, soy and baked goods.

A Mediterranean diet is high in omega-3 fatty acids which include eicosapentaenoic acid (EPA) and docosahexaenoic (DHA). Low levels of omega-3s in may contribute to hearth disease and some cancers. The best source of EPA and DHA omega-3 fatty acids is fatty fish. Other sources of omega-3 fats are flaxseed oil, walnuts, and leafy green vegetables. 

 Hydrogenated vs. Partially hydrogenated

In recent years there has been a lot of controversy over eating fats that are hydrogenated vs. partially hydrogenated.  What does hydrogenation mean?

The answer lies with the atom hydrogen.  Due to the chemical make up of polyunsaturated fats, the product is susceptible to spoilage decreasing its shelf life.  Spoiled polyunsaturated fats give off aldehydes that produce a rancid odor.

To increase shelf life, manufacturers add hydrogen to oils producing a more stable molecule by transforming it from a liquid to a solid or semi-solid depending on the process.  Margarine made from vegetable oil is solid at room temperature because the oil has been partially hydrogenated.

The problem with hydrogenation it that it reduces the polyunsaturated fat content converting polyunsaturated fat to saturated fat which reduces the fats health benefits.

There is overwhelming evidence about health risks associated with oils that are partially hydrogenated.

Trans Fat

A vegetable oil that is fully hydrogenated becomes a solid that is virtually indistinguishable from saturated fats.  When oils are partially hydrogenated, the chemical structure of the product is referred to as a trans fat.

Trans fatty acids are not made by your body’s cells and they are rarely found in the foods you eat.  How our bodies deal with the large quantities of trans fatty acids from eating foods with partially hydrogenated oils has been the topic of serious debate over the last few years.   Beginning in 2006, the USFDA requires the amount of trans fat be listed on nutritional labels.

Food manufacturers have followed suit by marketing products with zero grams of trans fat.  But have zero grams of trans fat is not the same as having no trans fat.  Some foods that advertise having zero grams of trans fat are made using partially hydrogenated oils.  Government regulations allows food manufacturers to claim the product has zero grams of trans fat if the amount of trans fat per serving is less than half a gram.

If you are concerned about eating trans fat check the list of ingredients for partially hydrogenated oils.

In 2013, the USFDA announced it was evaluating banning trans fat. Read more by clicking here.

Until trans fats are banned,some foods like microwave popcorn and fast food biscuits and fried foods can have trans fat exceeded the recommended 2 to 3 grams per day. Trans fat is proven to raise LDL cholesterol increasing the risk of artery clogging plague that can cause a heart attach or stroke.

Eating this foods with high levels of trans fat occasionally is low risk. A steady diet of high trans fat foods increases your risk of heart attack and stroke.

Cholesterol

You have seen the ads and your doctor may even have told you that high cholesterol is bad and low cholesterol is good.  Cholesterol is found in foods containing fat and is made by your body in the liver.  Cholesterol is needed for your body to process fat.  The raw materials needed by your liver to make cholesterol is available from glucose and saturated fatty acids.  Eating a diet of high saturated fat foods can increase blood cholesterol.

After being manufactured by your liver, the cholesterol either leaves or is made into hormones.  The cholesterol that leaves the liver has three possibilities:

  • It can be made into bile which is stored in the gallbladder until needed or moved into the intestine where some may be excreted.
  •  It can be deposited in your body tissues.
  •  It can end up accumulating in your arteries.

It is the cholesterol that accumulates in your arteries that is the main concern.  That cholesterol is derived from saturated fats and foods.  That is the reason why doctors recommend a diet low in saturated fats which is one of the benefits of a Mediterranean diet.

By reducing your intake of saturated fat you can reduce your risk for heart disease.  Unfortunately, simply reducing or eliminating foods containing saturated fats doesn’t guarantee you will never have heart disease.  There are hereditary factors to consider.  Some people due to their genetic code have high levels of cholesterol made by their liver .  You can control what you eat, but there is nothing you can do at this time about your genes.

Eating a Mediterranean style diet will reduce your consumption of saturated fats that can help you lose weight and reduce your blood cholesterol.

Blood Cholesterol Levels

Their are two types of blood cholesterol; low density lipoproteins (LDL) and high density lipoproteins (HDL).  LDL is classified as bad cholesterol and HDL as good cholesterol.    The American Heart Association (www.americanheart.org) has published the following guidelines for total blood cholesterol (LDL + HDL):

Desirable

Less than 200 mg/dL

Borderline high risk 200–239 mg/dL
High risk 240 mg/dL and over

 

For an individual with a very low risk of heart disease your LDL should be less that 160 mg/dL and your HDL greater than 40 mg/dL.  People with one or more risk factors should have LDL less than 130 mg/dL.

Foods High in Saturated Fat

Foods high in saturated fats are some of my, and I am sure your, favorite foods.  They include milk, eggs, cheese, meat, beef, and pork.

An easy test for saturated fat is how hard it is at room temperature. Eating more poultry, fish and vegetables and less red meat will significantly decrease the amount of saturated fat in your diet.  For people who must have some red meat,  portion sizes can be reduced.  For example, from 8 ounces to 4 ounces.  Trimming off excess fat or eat leaner cuts of meat will also reduce the amount of saturated fat in your diet.  By combining both leaner cuts of beef or pork with smaller portion sizes you have the best of both worlds by reducing the amount of saturated fat and calories in your diet.

Reducing Fats in Your Diet

There are many ways to reduce the amount of fat in your diet without giving up foods you love. Replacing saturated fats with polyunsaturated and monounsaturated fats can reduce blood cholesterol and atherosclerosis.

Restrict or Avoid Substitute
Butter, coconut oil, trans fats Olive, canola or other polyunsaturated oils. Trans fat free margarine
Gravies or cream sauces made with animal fats Vegetable oils, strained meat juices
Salad dressing containing cheese or sour cream Oil and vinegar dressings
Whole milk, cream, full fat cheese Skim, 2% or 1% milk, dried nonfat milk, low fat cheeses
Fried meats and fish
Bacon, cold cuts, sausage, hot dogs, corned beef
Goose, duck
Fish roe and caviar
Spareribs
Hamburger
Frozen dinners
Whole eggs
Lean, trimmed beef, lamb, pork or ham
Chicken, turkey
Fish
Egg whites
Biscuits, muffins, sweet rolls, corn bread, pancakes, waffles, French toast, hot rolls, corn and potato chips, flavored crackers In moderation, whole wheat or rye bread, saltine crackers, graham crackers, low fat baked goods
Corn, creamed or fried vegetables unless prepared with monounsaturated or polyunsaturated fats Non-starchy vegetables, fresh, frozen, or cooked without added fat
Creamed soups Low sodium clear broths, fat-free vegetable soup, creamed soup made with low fat milk
Chocolate, coconut Any unsweetened fresh, frozen or canned fruits or juices
Pies, cakes, cookies, other desserts containing whole milk, saturated fats or egg yolks Angel food cake, puddings, or frozen desserts made with low fat milk, gelatin
Ice cream, iced milk, sherbet, whipped toppings Italian ices
Alcohol ,except in moderation