Fat Fundamentals: the Good, the Bad and the Sincerely Ugly!

For a little word,
it packs some serious weight.


Nothing, it seems, strikes fear and loathing into the hearts of Americans the way FAT does--a three-letter word that’s loaded with significance, not to mention hefty health consequences. 
The simple fact is, as a country we’re spreading out. Try this on for size: According to the American Heart Association, 23.4 million children between the ages of 2 and 19 are overweight or obese. Among adults 20 and older, 145 million are overweight. That’s an epidemic, according to the Centers for Disease Control and Prevention (CDC), which notes that “from 1980 through 2008, obesity rates for adults have doubled and rates for children have tripled.”
There’s even a new medical term for it: obesogenic. According to the CDC, our society has become “characterized by environments that promote increased food intake, nonhealthful foods, and physical inactivity.” The fallout? Rising rates of heart disease, cancer, diabetes, high blood pressure, stroke, liver disease, and osteoarthritis. Medical costs for obesity-related care in the U.S. run close to $150 billion a year.
Fat Facts
It might be tempting to point an accusatory finger at fat itself, blaming our spreading middles on a diet of fatty foods. But that finger may be wagging due to a fundamental misconception—that fat is a bad thing. 
The truth is, not all fat is bad. In fact, fat is essential to our health--if it’s the right kind. The body uses fatty acids (the building blocks of fat) for an unimaginable number of productive purposes. Sixty percent of the brain is composed of fat, and the heart gets more than half of its energy from it. Fat keeps our lungs from collapsing and cushions our internal organs; it protects nerves and keeps cells flexible; it allows the body to absorb fat-soluble vitamins A, D, and E; and it keeps the immune system healthy.
Here’s the bite-sized skinny on fats:

1. Unsaturated Fats
Consummate good guys, these improve cholesterol and lower the risk of heart disease. Derived mainly from plants, there are two basic types:

  • Monounsaturated: These fats are found in olive, peanut, and canola oils; also almonds, pumpkin seeds, and sesame seeds.
  • Polyunsaturated: Look for these in sunflower and flaxseed oils, walnuts, and fish. This group includes the all-important omega 3s, which must be obtained from food, as the body can’t manufacture them.
In one study that replaced dietary carbs with poly- and monounsaturated fats, harmful levels of LDL (bad) cholesterol fell, and HDL (good) increased. The recent OmniHeart randomized trial showed that blood pressure and risk of cardiovascular disease (CVD) were also reduced.
2. Saturated Fats
Considered one of the major culprits in CVD, most saturated fats come from whole-milk dairy products (cheese, milk, and ice cream) and red meat. The body manufactures all the saturated fat it needs, so there’s no need to add more.
3. Trans Fats
True bad boys, these harmful “mutant” fats are created by heating liquid vegetable oil in the presence of hydrogen gas—hence, hydrogenation. They’re not good for you, but partially hydrogenated fats have a long shelf life, making them the darling of the food industry, where they’re a major component in fast, fried, snack, and processed foods. Trans fats raise LDL, lower HDL, and mess with the immune system, leading to stroke, diabetes, and heart disease. According to the New England Journal of Medicine, “eliminating trans fats from the U.S. food supply could prevent between 6 and 19 percent of heart attacks and related deaths, or more than 200,000 each year.”

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