Chapter 11

Fat Production and Dietary Fats

As was alluded to in previous chapters, body fat is a very necessary evil. It serves as a storage receptacle for unused glycosol (sugar) and other toxins that must be taken from the blood when their levels become intolerable. Thus fat production is a homeostatic bodily response to unused quantities of toxins in the blood.

            The human body contains two types of fat tissue:

     White fat is important in energy metabolism, heat insulation and mechanical cushioning.

     Brown fat is found mostly in newborn babies, between the shoulders, and is important for thermogenesis (making heat).  

     Fat tissue is made up of fat cells, which are a unique type of cell. You can think of a fat cell as a tiny plastic bag that holds a drop of sugar.

Vitamins A, D, E, and K are fat-soluble, meaning they can only be digested, absorbed, and transported in conjunction with fats. Fats are sources of essential fatty acids, an important dietary requirement.

Fats play a vital role in maintaining healthy skin and hair, insulating body organs against shock, maintaining body temperature, and promoting healthy cell function. They also serve as energy stores for the body. Fats are broken down in the body to release glycerol and free fatty acids. The glycerol can be converted to glucose by the liver and thus used as a source of energy.

Fat also serves as a useful buffer towards a host of diseases. When a particular substance, whether chemical or biotic -- reaches unsafe levels in the bloodstream, the body can effectively dilute -- or at least maintain equilibrium of the offending substances by storing it in new fat tissue.

An astounding  fact is that fat cells generally do not generate after puberty; as your body stores more fat, the number of fat cells remains the same. Each fat cell simply gets bigger!

 

Dietary Fats

Dietary fat, the kind of fat you get from food, is important for your health and the normal growth and development of your body. Dietary fat has many different functions in your body, which include:

         Providing long lasting energy

         Helping you feel full after eating

         Helping make hormones

         Forming part of your brain and nervous system

         Forming cell membranes for every cell in your body

         Carrying vitamins throughout your body

         Helping to regulate your body temperature and keep you warm

         Providing two essential fatty acids, called linoleic acid and linolenic acid, that your body cannot make by itself

Your body needs fat to function properly. Besides being a significant energy source, fat is a nutrient used in the production of cell membranes, as well as in several hormone-like compounds called eicosanoids. These compounds help regulate blood pressure, heart rate, blood vessel constriction, blood clotting and the nervous system. In addition, dietary fat carries fat-soluble vitamins vitamins A, D, E and K from your food into your body. Fat also helps maintain healthy hair and skin, protects vital organs, keeps your body insulated, and provides a sense of fullness after meals.

 

The U.S. Department of Agriculture (USDA) and the Department of Health and Human Services (HHS) recommend that fat make up no more than 35 percent of your daily calories. Most foods contain several different kinds of fats including saturated, polyunsaturated, monounsaturated and trans fats and some kinds are better for your health than others.

The four main types of fat found in food are monounsaturated fat, polyunsaturated fat, saturated fat, and trans fat. Most foods have a different balance of these types of fats, but are usually classified by the type of fat they are highest in.

Saturated and monounsaturated fats are not necessary in the diet as they can be made in the human body.

Two polyunsaturated fatty acids (PUFAs) that cannot be made in the body are linoleic acid and alpha-linolenic acid. They must be provided by diet and are known as essential fatty acids. Within the body both can be converted to other PUFAs such as arachidonic acid, or eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA).

In the body PUFAs are important for maintaining the membranes of all cells; for making prostaglandins which regulate many body processes which include inflammation and blood clotting. Another requirement for fat in the diet is to enable the fat-soluble vitamins A, D, E and K to be absorbed from food; and for regulating body cholesterol metabolism.

Omega-3 polyunsaturated fatty acids (PUFAs) are essential for human health, but their intake has gradually declined over the years. It is believed that man evolved on a diet with a ratio of omega-6 to omega-3 PUFAs of about 1:1. Today this ratio is more like 10:1 and in some societies is approaching 25:1. A relative over-abundance of omega-6 PUFAs has been implicated in excessive blood clotting, allergic and inflammatory disorders, and certain cancers. 

An adequate intake of omega-3 PUFAs, on the other hand, has been linked to improved cardiovascular health. A recent study concluded that a daily intake of 500 to 1000 mg of long chain omega-3 PUFAs reduces the risk of cardiovascular death in middle-aged American men by about 40%. 

Other studies have shown that although fish oils help prevent undesirable blood clotting reactions they do not increase bleeding time and are quite safe even for people scheduled for major surgery. 

Animal studies have found that fish oil supplementation markedly reduces the risk of fatal arrhythmias. 

Fish oils have also been found beneficial in preventing or treating hypertension, arthritis, psoriasis, ulcerative colitis, cancer, and certain diabetes- related complications. EPA and DHA are both essential for pregnant mothers and infants and a deficiency can retard the development of the brain and retina.

Polyunsaturated Fatty Acids - Dietary Sources

Food sources of the two main dietary polyunsaturated fatty acids (linoleic acid and alpha-linolenic acid) are listed below.

Linoleic Acid (Omega 6 family)
  • Vegetables
  • Fruits
  • Nuts
  • Grains
  • Seeds

Good sources:

Oils made from:

  • Safflower
  • Sunflower
  • Corn
  • Soya
  • Evening primrose
  • Pumpkin
  • Wheat germ.

Alpha-Linolenic Acid (Omega 3 family)

 

(Please note - fish is not the only source of omega 3 acids. Flaxseed oil contains twice as much as is found in fish oil!).

  • Flaxseeds (linseeds)
  • Mustard seeds
  • Pumpkin seeds
  • Soya bean
  • Walnut oil
  • Green leafy vegetables
  • Grains
 

Good sources

Oils made from:

  • Linseed (flaxseeds)
  • Rapeseed (canola)
  • Soya beans
  •  

EPA's and DHA's

 

Alpha-linolenic Acid is converted in the body to EPA (eiocosapentaenoic acid) usually found in marine oil and DHA (docosahexaenoic acid) usually found in marine fish oil.

Monounsaturated fat is considered the most "heart healthy" type of fat. Monounsaturated fats decrease LDL ("bad") cholesterol and increase HDL ("healthy") cholesterol.

 

Good sources of monounsaturated fat include:

 

Avocados

Olive Oil

Almonds

Peanut butter

Canola Oil

Peanut Oil

Cashews

Sunflower Oil

Hazelnuts

 

  

Polyunsaturated fat is also a "heart healthy" type of fat. 

There are two essential fatty acids (linolenic and linoleic) that your body uses to make chemicals that control blood pressure, blood clotting, and your immune system response. Linolenic fatty acids are also called Omega-3 fats, and they have many health benefits. Omega-3 fatty acids may be especially beneficial to your heart. Omega-3s appear to decrease the risk of coronary artery disease. They may also protect against irregular heartbeats and help lower blood pressure levels.

 

EPA (eicosapentaenoic acid) and DHA (docosahexaenoic acid)

 

Fish oils either from whole fish or in the form of supplements (neither has been shown to have a more advantageous affect) have been found to aid in preventing or ameliorating coronary heart disease, stroke, lupus, nephropathy (kidney disorders), Crohn's disease, breast cancer, prostate cancer, colon cancer, hypertension, and rheumatoid arthritis. Fish oils have been found particularly effective in preventing arrhythmias and sudden death from cardiac arrest. People who eat fish once or more each week can reduce their risk of sudden cardiac death by 50-70 per cent. EPA has been found to inhibit blood clotting and EPA and DHA contained in fish oils inhibit the development of atherosclerosis. 

Fish oil supplementation also significantly lowers overall triglyceride and cholesterol levels without affecting the level of HDL (good cholesterol). EPA and DHA play a crucial role in the prevention of atherosclerosis, heart attack, depression, and cancer. Clinical trials have shown that fish oil supplementation is effective in the treatment of many disorders including rheumatoid arthritis, diabetes, ulcerative colitis, depression, Alzheimer's disease, ADS, schizophrenia, manic depression, and Raynaud's disease.

 

Good sources of polyunsaturated fat include:

Canola Oil

Sardines

Corn Oil

Sesame Seeds

Cottonseed Oil

Soybeans

Flaxseeds

Soybean Oil

Herring

Sunflower Oil

Mackerel

Tuna

Pine Nuts

Trout

Pumpkin Seeds

Walnuts

Salmon

 

Good sources of Omega-3 fats include:

Canola Oil

Legumes

Fish

Mackerel

Flaxseeds

Nuts (such as walnuts)

Flaxseed oil

Sardines

Green, leafy vegetables

Soy based foods
(soybean, soy nuts)

Halibut

Tofu

Lake Trout

Tuna

 

DHA is the building block of human brain tissue and is particularly abundant in the grey matter of the brain and the retina. Low levels of DHA have recently been associated with depression, memory loss, dementia, and visual problems. 

DHA is particularly important for fetuses and infants; the DHA content of the infant's brain triples during the first three months of life. Optimal levels of DHA are therefore crucial for pregnant and lactating mothers. Unfortunately, the average DHA content of breast milk in the United States is the lowest in the world, most likely because Americans eat comparatively little fish. Making matters worse is the fact that the United States is the only country in the world where infant formulas are not fortified with DHA. This despite a 1995 recommendation by the World Health Organization that all baby formulas should provide 40 mg of DHA per kilogram of infant body weight. 

It is believed that postpartum depression, attention deficit hyperactivity disorder (ADHD), and low IQs are all linked to the dismally low DHA intake common in the United States. 

Low DHA levels have been linked to low brain serotonin levels, which again are connected to an increased tendency to depression, suicide, and violence. 

DHA is abundant in marine phytoplankton and cold-water fish. Nutritionists now recommend that people consume two to three servings of fish every week or the Fish Oil suplimentation of 500 to 1,000 mg per day to maintain DHA levels.
  

 

 

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