Are the health benefits associated with apple consumption simply due to other healthy behaviors among apple-eaters?
Regular apple intake is associated with all sorts of good things, like living longer—particularly a lower risk of dying from cancer. Here’s the survival curve of elderly women who don’t eat an apple a day. Ten years out, nearly a quarter had died, and 15 years out, nearly half were gone. But, those who average like a half an apple a day don’t drop off as fast, and those eating an apple a day—more than three and a half ounces of apples a day—like a cup of apple slices—stayed around even longer. Yeah, but maybe people who eat apples every day just happen to practice other healthy behaviors, like exercising more, or not smoking, and that’s really why they’re living longer. Well, they controlled for most of that—obesity, smoking status, poverty, diseases, exercise—so as to compare apples to apples (so to speak!).
But, what they didn’t control for was an otherwise healthier diet. Studies show that those who regularly eat apples have higher intakes of not just nutrients like fiber, found in the apples, but they’re eating less added sugar, less saturated fat—in other words, they’re eating overall healthier diets. So, no wonder apple eaters live longer, but is apple eating just a marker for healthy eating, or is there something about the apples themselves that’s beneficial? You don’t know, until you put it to the test.
There are all sorts of fun studies like this, where subjects were randomly assigned in the morning to nothing, a caffeinated energy drink, black coffee, or an apple—given that athletes use a variety of common strategies to stimulate arousal, cognition, and performance before their morning training. Did the apple hold its weight? Yes, appearing to work just as well as the caffeinated beverages. The problem with these kinds of studies, though, is that they’re not blinded. Those in the apple group knew they were eating an apple. So, there may have been an expectation bias, placebo effect, that made them unconsciously give that extra bit of effort in the testing, and skew the results. You just can’t stuff a whole apple into a pill.
That’s why researchers, instead, test specific extracted apple components. So, they can perform a double-blind, placebo-controlled study, where half get the fruit elements, half get a sugar pill, and you don’t know until the end who got which. The problem there, though, is that you’re no longer dealing with a whole food—removing the symphony of interactions between the thousands of phytonutrients in the whole apple.
Most of those special nutrients are concentrated in the peel, though. Instead of just dumping millions of pounds of nutrition in the trash, why couldn’t researchers just dry and powder the peels into opaque capsules to disguise them, and then run blinded studies with that? Even just “[a] small amount could greatly increase…phytochemical content and antioxidant activity…”
The meat industry got the memo: “Dried apple peel powder decreases microbial expansion in [meat] and protects against carcinogen production…” when you cook it. And, “[o]ne of the carcinogens formed during [the] grilling of meat is [a] beta-carboline” alkaloid, a neurotoxin, which may be contributing to the development of neurological diseases, like Parkinson’s. I did a video about that a while ago. Uncooked meat doesn’t have any; the neurotoxin is formed when you cook it. But, you can cut the levels in half by first marinating the meat with dried apple peel powder.
And, it also cuts down on the amount of fecal contamination bacteria in the meat. Fecal bacteria growing before and after the addition of dried apple peel powder, in pork, beef, and turkey. Apple peels can also inhibit the formation of genotoxic, DNA-damaging, heterocyclic amines, cutting the levels of these cooked meat carcinogens by up to more than half. “In view of the risks associated with consuming [these cancer-causing compounds in meat], there is a need to reduce exposure by blocking HCA formation such as by adding [apple peel powder] during the cooking of meats to [help] prevent their production.” I can’t think of any other way to reduce exposure.
What about consuming apple peels directly? Dried apple peel powder was found to exhibit “powerful anti-inflammatory and antioxidant action.” But, this was in mice. Does it have anti-inflammatory properties in people? You don’t know, until you put it to the test.
A dozen folks “with moderate loss of joint [range of motion] and associated chronic pain” were given a spoonful of dried apple peels a day for 12 weeks, and pain scores dropped month after month, and the range of motion improved in their neck, shoulders, back, and hips. Conclusion: “Consumption of dried apple peel powder was associated with improved joint function and…pain reduction.” Why just “associated”? Because there was no control group; so, they might have all been just getting better on their own, or it could have been a placebo effect. But hey, why not give apple peels a try by eating more apples?