Staying well as you progress through your life depends on numerous factors, and the quality of the dietary fats you consume is a very important one.

Although you need a certain amount of fat in your diet, not all fats are created equal where your wellness is concerned. Some fats are closely linked to illness, while others are indispensable for optimal health.

Learning to distinguish between "good" and "bad" fats—and then putting that knowledge into action—can dramatically benefit your health profile and reduce your risk of degenerative disease down the line.

Minimize saturated fat and trans fats

There are three classifications of dietary fats:

• saturated
• monounsaturated
• polyunsaturated

Saturated animal fats—found primarily in meats and dairy products—are those most strongly linked to heart disease, cancer and diabetes, among other health problems.

"Trans-fatty acids"—unnaturally saturated fats found in hydrogenated oils—are made when liquid oils are artificially saturated with hydrogen to form solid fats. These unhealthy fats have been linked to cardiovascular disease, as illustrated by a study from the journal Nutrition Review (1993 Nov;51(11):340-3).

Mary Enig, PhD, is a Boston researcher who has studied dietary fats since 1977. She notes that trans-fatty acids also have been shown to raise total cholesterol, lower HDL "good" cholesterol, increase LDL "bad" cholesterol, decrease immune function and insulin response and are linked to pregnancy and reproductive problems.

Trans-fatty acids are found in fried foods, margarine, store-purchased crackers, chips and baked goods, and all other items with food labels listing "partially hydrogenated oils."

Tips from the Mediterranean diet

Monounsaturated fats, found in olive oil, avocado, peanuts and others nuts—though not considered essential—offer numerous health benefits.

Olive oil helps to raise HDL "good" cholesterol while lowering LDL "bad" cholesterol. Furthermore, olive oil's antioxidant properties help prevent LDL from oxidizing and damaging arteries with plaque.

Not only does olive oil promote a healthy heart, it may help prevent breast cancer, according to a recent study in the journal Anticancer Research (2000 Jul-Aug;20(4):2307-12).

Unprocessed nuts also deserve special mention, as they help to reduce cholesterol and our risk of heart disease (Nutr Rev 2001 Apr;59(4):103-11), (Curr Atheroscler Rep 1999 Nov;1(3):204-9).

In fact, four of the largest cohort studies in nutritional epidemiology have now reported that eating nuts frequently is associated with a 30-50% decreased risk of coronary heart disease (Clin Cardiol 1999 Jul;22(7 Suppl):III11-5).

Polyunsaturated fats—found in most plant foods, vegetable oils, and cold-water fish—supply essential fatty acids (EFAs), which are vital for healthy body function. These fats are referred to as "essential" since they must be provided by the diet, and can't be manufactured in your body.

EFAs consist of omega-6 linoleic acid and omega-3 alpha-linolenic acid. The omega-6 fatty acids, commonplace in the diets of many Americans, are found in most nuts, seeds, and vegetable oils. The omega-3 fatty acids—far less frequently consumed by Americans—are supplied by flaxseeds and flaxseed oil, hemp seeds, pumpkin seeds, walnuts, dark leafy greens and cold water fish, such as salmon, tuna, and mackerel.

Flax oil is an extremely rich source of the omega-3 EFAs, with up to a 60 percent concentration of these vital fats, according to the Physicians Desk Reference for Nutritional Supplements (Medical Economics, 2001).

Essential fatty acids and optimal health

Optimal health depends on eating the right balance of the omega-3 and omega-6 fatty acids. Dr. Michael Murray, N.D., author of The Encyclopedia of Nutritional Supplements (Prima Publishing, 1996), discusses the optimal ratios of omega-3 to omega-6 EFAs.

He notes that although the ideal ratio of omega-6 to omega-3 is 4:1, most Americans consume far more omega-6 than omega-3 EFAs—typically at a ratio of 20:1. Dr. Murray points out that this imbalance is largely due to the fact that omega-6 EFAs are the primary oils found in refined oil products and most processed foods.

The correct balance of omega-3 to omega-6 fatty acids is critical to proper prostaglandin metabolism. Prostaglandins are hormone-like chemicals which support healthy body function in numerous ways.

According to a recent study in the journal Lipids (2001 Sep;36(9):1007-24), prostaglandins play important roles in inflammation and the regulation of the immune system.

In her book, Eat Fat, Lose Weight (Keats, 1999), author Ann Louise Gittleman, M.S., C.N.S. discusses the ways in which prostaglandins assist in the body's fight against a variety of conditions ranging from arthritis and ulcers to migraines and cancer.

She notes that prostaglandins also boost our cardiovascular, reproductive, immune, and central nervous systems, as well as help to regulate energy production and fat metabolism.

Udo Erasmus, author of Fats That Heal, Fats that Kill (Alive Books, 1993), points out other reasons to ensure an adequate dietary intake of the omega-3 and omega-6 EFAs. He discusses the many serious health conditions associated with EFA deficiencies, including hair loss, skin disorders, susceptibility to infection, arthritis, liver and kidney degeneration, growth retardation and vision or learning problems.

More health benefits of EFAs

The health benefits of proper EFA consumption are beyond dispute.

Considerable scientific data, including a study from the Canadian Journal of Physiological Pharmacology (1997 March;75(3):234-9) shows that omega-3 fatty acids have proven beneficial in helping to prevent heart attacks, as well as cardiac arhythmias. In fact, the same study cites that fish oil, a rich source of the omega-3 EFAs, helps to reduce ventricular arrhythmias more effectively than medication.

Dr. Murray offers a further wealth of information on the benefits of omega-3 EFA supplementation, noting that more than 60 health conditions can benefit from these essential fats. These include acne, allergies, athero-sclerosis, AIDS, cancer, diabetes, heart disease, rheumatoid arthritis, menopause, multiple sclerosis, osteoarthritis and inflammatory conditions.

Although we can't stop the normal aging process, research suggests that we have considerable control over our rate of premature aging and risk of degenerative disease.

Incorporating adequate levels of essential fatty acids will promote our optimal health in numerous ways. By minimizing saturated animal fats and trans fats, and supplementing with healthy fats like flax seed, olive and fish oils, we can more effectively protect our bodies against premature aging and degenerative disease while actively promoting our own wellness.