While everyone talks about saturated fat and monounsaturated fat, polyunsaturated fat and trans fat, I’m going to give you a better strategy for figuring out what to eat. Instead of FAT, let’s talk about FATTY ACIDS.
If “fat” is a word, then fatty acids are the letters. If “fat” is a sentence, then fatty acids are the words. If “fat” is the solar system, then fatty acids are the planets and moons. If “fat” is the universe, then fatty acids are the galaxies. Fat is the pyramids, and fatty acids are the bricks. The most beautiful building in the world, if built with substandard materials, will eventually collapse to the ground. And the same goes for nutrients: the food with the most appetizing appearance will not nourish you if it is built from a limited array of poor-quality fatty acids.
If foods are words, then it’s time to focus on the letters: Today, we’re talking not about olives or avocados, but about the o’s and the e’s comprising them. The conversation is not about lard or chicken fat. It’s about the fatty acids of which they are built.
Here’s how it works:
Every fat molecule consists of three fatty acids, each of which is attached at one end to a glycerol molecule, which you can think of as the molecule’s backbone. Each fatty acid (consisting of a chain of carbon molecules) is completely independent from the others. Sometimes two or maybe even all three of the fatty acids are identical, but more often than not, they are all different. Fatty acids can be long (say 20 carbon molecules or more in length) or short (just a few carbon molecules long). Because each fatty acid has a different job to perform, it’s good to get a variety in your diet.
And length is not the only way that fatty acids vary one from another. There is also the matter of “saturation.” Saturation refers to how thoroughly the carbon molecules’ outer rings are packed with hydrogen molecules. If every space on every single carbon in a fatty acid is completely packed with molecules of hydrogen, we say that the fatty acid is saturated. If a single space is still available for one more hydrogen, we call that monounsaturated. Mono- comes from the Greek word for “one.” Finally, if more than one space is available, that molecule is called polyunsaturated.
Somewhere along the line, we got the impression that the more saturated a fat is, the more likely it is to cause disease. And vice versa. I’m going to present you with evidence to suggest that there’s more to this, and that we don’t have the whole picture. Yet.
Let’s start with saturated fatty acids. One of the fats in our diet with a high proportion of saturated fatty acids is cocoa butter. Cocoa butter is the primary fat in dark chocolate. We have good data and research on the beneficial health effects of eating dark chocolate. What does that tell me? One thing. That we don’t know the whole story.
What about monounsaturated fatty acids? The most commonly discussed fat in this category is olive oil, of which three-fourths of its fatty acids are monounsaturated. Yes, the rest are divided among saturated and polyunsaturated fatty acids. At 70% for avocados and 65% for almonds, these two foods also are sky high in monounsaturated fatty acids. Other fat sources containing significant amounts of monounsaturated fatty acids include sesame oil (40%), lard [pork fat] (45%), peanut oil (45%), chicken fat (~50%) and goose fat (52%). What? I know, it’s really confusing. If lard, chicken fat, and goose fat are high in monounsaturated fatty acids, then what’s going on? Are they okay or not?
What does this tell me? That we still don’t have all the facts. In the meantime, I would say that it is no longer necessary that scrape every last bit of fat and skin off all the chicken breasts before you cook them. Enjoy your dinner.
And what about polyunsaturated fatty acids? Corn oil (60%) and tub margarine (~50%) are two examples of items with high concentrations of polyunsaturated fatty acids. Sunflower oil is even higher at ~70%. Unfortunately, not all polyunsaturated fatty acids are equal. If you’ve heard of omega-3’s and omega-6’s, this is the class of fatty acids where they live. And whereas omega-3 fatty acids appear to have a significant anti-inflammatory effect, unfortunately omega-6’s are pro-inflammatory. That doesn’t mean they’re bad; we need pro-inflammatory mediators in our diet to fight foreign invaders. But you don’t want a lot more omega-6’s than -3’s. You want an even balance, more or less. So it’s not so simple.
Flaxseeds and edamame are also very high in polyunsaturated fatty acids. That’s good, right? In the case of flaxseeds, edamame, and sunflower seeds, sure. Definitely. Eat away! But in the case of corn or sunflower oil, there’s more here than meets the eye.
According to a major evaluation (meta-analysis) of many studies of fatty acid intake and polyunsaturated fat supplementation, the findings DID NOT support currently accepted guidelines promoting consumption of polyunsaturated fatty acids and recommending reduced consumption of saturated fatty acids. The researchers decided that further research is necessary, especially in healthy individuals. So far, so good. But here’s their conclusion: Until we understand better, they said, people should stick to the current guidelines on fat consumption. Even though they just showed that the guidelines are not consistent with the observed outcomes? No, thank you.
At this point, my plan is to do my best to eat whole foods like well-raised dairy, eggs, poultry and meats, tons of vegetables, beans, fruit, nuts and seeds, not to mention olive oil, peanut butter, avocado oil and so on. And nothing that was invented in the 20th century, at least to the extent reasonable.