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When one sees headlines like, “Avocados Could Improve Your Cholesterol,” they’re largely talking about substitution experiments, where avocado is added to the diet by replacing animal fats. So, no wonder cholesterol goes down. So, for example, if you take people eating a standard North American diet, including animal fats—dairy and poultry are the two greatest contributors of cholesterol-raising saturated fat intake—they may start out with an LDL up around here. Just add avocado to their diet without doing anything else, and cholesterol does not go down. But, add avocado while reducing saturated fat intake, and cholesterol falls—but no more than just reducing saturated fat while adding nothing.

Okay, but what if you eat no meat at all, versus no meat with avocado added? They took people with sky-high cholesterol—up around 300—and switched them to a relatively low-fat vegetarian diet, with about 20% of calories from fat, versus a vegetarian diet with added avocado—bringing it up to more of a typical fat content: 30% of calories from fat. This group started out with LDLs through the roof, and while cutting out meat may have helped, cutting out meat and adding avocado seemed to help even more. And, it may help best with the worst type of LDL.

As I’ve touched on before, all LDL cholesterol is bad cholesterol, but large, fluffy LDL may only increase the odds of cardiac events—like heart attacks—31%, whereas small, dense LDL is even worse.

Feed people lots of oatmeal and oat bran, and not only does their LDL go down overall, but it specifically brings down the worst of the worst. Add walnuts to a low-fat diet, and not only does LDL go down, but the size distribution of the LDL shifts to a little more benign as well. And, if you put people on a plant-based diet with lots of fiber and nuts, you can get a massive 30% drop in LDL, comparable to a cholesterol-lowering statin drug. And, this includes the small, dense, most dangerous LDL. Note: this does not happen with extra-virgin olive oil. So, it’s not just a monounsaturated fat effect.

In the famous PREDIMED study, those randomized to the extra nuts group got a significant drop in the smallest, densest LDL, but those randomized to the extra virgin olive oil group did not. So, there appears to be some special components in nuts that lowers the worst of the worst. Do avocados offer similar benefits? We didn’t know…until, now.

“…[t]he first randomized controlled feeding trial” to look at avocados and LDL size; what they did was remove animal fat from people’s diet, and replaced it with either carbs, or avocado, or vegetable oils that had a similar fat profile to the avocado. So, the two latter diets were very similar diets, but one had the nutrients unique to the avocado, and the other didn’t. What happened?

Well, any time you drop saturated fat, you’re going to bring down LDL—whether you replace animal fat with plant fat (oil, in this case) or with carbs. But, what if you replace animal fat with the whole plant food avocado? An even better effect. And, to see why, they broke the LDL down into large versus small. They all brought the dangerous, large LDL down, but the avocado had the additional effect of also bringing down the super-dangerous small LDL. That’s where that extra drop came from.

So, it’s not just a matter of replacing animal fat with plant fat; there are additional benefits to the fiber and phytonutrients of whole plant foods, like avocados.

Oh, there’s something good in avocados? Well then, let’s just add avocado extracts to the meat! Incorporating avocado extracts into pork patties evidently reduces cholesterol oxidation products, “well documented” to be toxic, carcinogenic, and atherosclerotic—but less so, apparently, with some avocado mixed in.

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