Back in the l980s, fat in food was considered the enemy of not only your thighs, but your arteries. Americans were advised to eat low-fat and even no-fat diets to drop pounds and promote health. Only, the result was something different – as a nation we got fatter than ever and developed type 2 diabetes in alarming numbers.

So what was the big fat problem? "The low-fat craze of the 1980's resulted in fat-free products that still had calories, yet people began consuming increased portions as though the calories didn't matter and they ate more carbs, too," registered dietician and certified wellness coach Julie Schwartz, MS, tells Synergy. The result was weight gain, upping the risk of type 2 diabetes and other diseases.

Atkins-type diets were the next weight loss craze and are still popular. Although they work temporarily, low carb diets are hard to stay on forever. Besides, that style of eating may lead to consuming too much saturated fat found in many meats, causing cholesterol levels to rise.

So what’s the healthy solution? Thanks to a mountain of research that’s accumulated over the last several decades, we now know healthy eating isn’t about either giving up all fats or eating as much fat as you want.

The truth is, not all fats are the same. In fact, some beneficial forms of fat can actually help keep weight under control and lower your risk of heart disease and other health problems. The key to healthy eating is understanding good vs. bad fats.

Amazing omega-3s

Essential fatty acids (EFAs) are necessary fats the human body can’t synthesize, so they must be obtained through what you eat. Omega-3 and omega-6 EFAS both have important functions. However, research has shown the typical American diet is loaded with omega-6s (found in many processed foods and corn, safflower, sunflower, soybean, and cottonseed oils), but woefully lacking in omega-3s (found in cold water fish like salmon and walnuts). This imbalance appears to contribute to health problems because too much omega-6 in the body promotes inflammation.

"Omega-3 benefits are most likely due to anti-inflammation properties," explains nutrition expert Schwartz, who also owns Nutriwell Coaching (http://www.nutriwellcoaching.com). "Consuming omega-3s has been shown to reduce symptoms of high blood pressure in certain people, help with Attention Deficit Hyperactivity Disorder (ADHD), aid joint health, improve skin problems, benefit gastrointestinal health, and more."

In fact, taking in more of this "good" fat could give you something to smile about -- literally. A study published in the Journal of the American Dietetic Association suggests omega-3s may prevent and also treat periodontal disease, which causes tissues that support the teeth to become inflamed. Left untreated, periodontal disease can be painful and cause tooth loss. Researchers from Harvard and Beth Israel Deaconess Medical Center discovered that the higher the intake of omega-3 fatty acids, particularly those known as docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA), the lower the incidence of gum disease.

More good news about these good fats:

An Emory University study published in the August edition of Pediatrics shows pregnant women who consumed omega-3 fatty acids regularly delivered babies who had fewer colds and shorter illnesses at one, three and six months of age.

• Studies by Tufts University researchers have linked increased levels of the omega-3 fatty acid DHA in the blood to a significantly reduced risk of dementia.
• Scientists at Children's Hospital Boston found omega-3s can help prevent retinopathy -- an eye disease caused by out-of-control growth of blood vessels in the retina that’s the leading cause of blindness affecting premature infants and more than four million adults in the U.S. with diabetes.
• Omega-3s may fight cancer, too. Researchers from the Fred Hutchinson Cancer Center in Seattle discovered that regularly taking a fish oil supplement lowered the risk of breast cancer by 32 percent.

The Mediterranean diet secret

The Mediterranean diet emphasizes, along with lots of fresh fruits, veggies and whole grains, and foods that are rich "good" fats. One big component of the diet is the monosaturated fat found in olives -- and olive oil has been linked to reducing the risk of heart disease, obesity, diabetes, and even depression.

Researchers at the University of Cordoba in Spain found that a diet rich in olive oil may help prevent metabolic syndrome. Characterized by excess abdominal fat, high cholesterol, high blood pressure and high blood glucose levels, metabolic syndrome may be a precursor to type 2 diabetes, heart disease, and early death. "These findings strengthen the relationship between inflammation, obesity, and diet and provide evidence at the most basic level of healthy effects derived from virgin olive oil consumption in humans," said lead researcher Dr. Perez-Jimenez.

The bad side of fat

Saturated fats, found mostly in animal products, can raise low-density lipoprotein (LDL) (the bad kind of artery clogging cholesterol, but that doesn’t mean this kind of fat is all bad – at least, not in moderation. Some research indicates there are beneficial short and medium chain fatty acids in cheese (especially goat’s cheese) which may have some health benefits. However, don’t go overboard. Nutrition expert Schwartz advises keeping saturated fats, which are loaded with calories, to under 10 percent of your total fat intake.

There is one type of fat that appears to be 100 percent BAD for human consumption – trans fats. Created in an industrial process that adds hydrogen to liquid vegetable oils to make them more solid, trans fats are found in processed foods. They also develop when oils are reheated multiple times for frying. According to the American Heart Association, they raise your bad (LDL) cholesterol levels and lower your good high-density lipoprotein (HDL) cholesterol levels. Eating trans fats increases your risk of developing heart disease, stroke and is linked to a higher risk of developing type 2 diabetes, too.

If you think you can avoid trans fats by reading labels, be aware that may not always be true. Another name for trans fats is "partially hydrogenated oils." Schwartz points out another sneaky labeling trick. "There can be trans fat in a food product but if it is .5 grams or less, it can be labeled as 0." Your safest bet to avoid trans fats? Skip processed foods, including potato chips and other pre-packaged snack foods.