Let's talk about fats. No, not adipose of which you are most likely trying to rid yourself, though we will touch on that in passing, but those that you ingest.
You need fats in your diet. Certain vitamins, A, D, E, & K, are what are known as fat-solubles, which is to say, you need fat to digest and absorb them. Deficiency in any of these vitamins is bad. A fat-free diet will eventually make you sick and probably kill you.
Fat produces slightly more than twice as much energy in the way of calories than do proteins and carbohydrates. Your body knows this and craves fat. It has a silky feel in the mouth–think really good ice cream–and it satisfies the taste buds in a way nothing else does. The old joke is that there are four main food groups -- fat, sugar, salt, and beer, and left alone, your body would gorge on 'em if your brain didn't step in and slap your body upside the head.
Some fats are worse for you than others. I say this without qualification: Animal fat will help clog your system more than plant fat. Saturated fats–those that are generally solid at room temperature–are not as good for you as unsaturated ones. (The jury seems to be still out on coconut oil, which is a solid and seems to be okay, but the verdict is "guilty" on lard. Even though everybody knows that lard makes the best pie crust.)
As a general and unhappy rule of thumb, the better it tastes and you more you crave it, the worse it is apt to be for you. Welcome to human physiology. The final exam counts for half your life expectancy ...
Cholesterol, which is a kind of waxy goop made from fat and necessary for cell health, is not a fat itself. It is usually broken out into HDL and LDL, and you want more of the former and less of the latter. If most of what you eat is steak and eggs slathered with butter and cheese and washed down with a triple-thick milkshake, you aren't getting them in the right proportions, trust me.
People who say there isn't any real evidence that high cholesterol in your system is linked to cardiac problems? They mostly live in the subdivision next to Mr. Toad's Wild Ride, in Fantasyland. Take your advice from them, you are playing Russian roulette with four loaded chambers.
Better you should get your fat from extra-virgin olive oil than from butter, cheese, cream, milk or eggs, despite what the American Dairy Association would have you believe.
Lean meat is better for you than marbled. Animal fat gums up your arteries, except fish oil, which tends to be in the "good" category. Assuming you aren't born with a genetic predisposition, how you usually get high cholesterol is from eating stuff with too much animal fat in it. The little cholesterol makers have a field day and go bananas.
The first time we really realized this was in doing autopsies on American troops killed in WWII. Here were all these farm boys, nineteen, twenty years old, who already had sclerotic arteries coated in cholesterol. Nineteen-year-olds from third world countries didn't have this problem. Why was that?
In a word, diet.
I'm not saying you shouldn't eat that omelet, nor that baked spud with butter and sour cream, but when you get right down to it, french fries cooked in quality vegetable oil are, in some ways, probably less likely to cause you medical problems, how is that for a twist?
Yeah, yeah, frying does carcinogenic things to oil, too, just like barbecue on the grill does, stipulated. Cancer kills a lot of folks, though heart disease and stroke combined are still the big winners, about 30%, with cancer at 23%, at least here in the U.S. And there is all kind of evidence that bad fats contribute to several kinds of cancer–bowel and breast and prostate all come readily to mind.
Okay, so don't trust me–you can look it up.
The stats aren't brainbreakers: The big three take out more than 50% of us in the states, and diet affects–to different degrees–all three.
Unsaturated fats–we are talking oils—are better for you.
Not every oil is equal. Monosaturates, like olive or peanut or sunflower tend to be better than polysaturate blends. Some, like palm or cottonseed, are cheap and used in fast foods, but don't offer some of the benefits of others.
Avocados drip with oil, as do nuts; you have to squeeze some things really hard to get the oil out, and how you process it makes a difference. Some oils are robust and work great for high-heat, especially frying. Some are delicate and break down when you crank up the fire. Olive oil makes a great dressing. It starts to smoke in the pan before sunflower or safflower do. I haven't tried macadamia nut oil yet, but I hear it's really good stuff on a green salad.
Eating fat does not make you fat, per se. But since it is calorically-dense, you do need to be aware that you are getting nine calories per gram instead of the four you get from carbs or protein. You get fat because you eat more than you burn. Nothing complex about that–if you eat less than you burn, you lose weight. The same? Why, you stay the same.
Read chapters 1-5 for next class. Any questions? Okay, we're done.