What Science REALLY Says About Chocolate, Coffee, Avocados & More

We all know that it’s important to be active and eat right. But what does it mean exactly to “eat right”? It’s tempting to turn to science for the answer, but browse the interwebs and you’ll see conflicting studies everywhere — fat’s good, fat’s bad; sugar’s poison, sugar’s fine — and it’s hard to know that to think.

Recently, a study from a team of German researchers came out touting chocolate’s positive effect on weight loss. It was going to be published in the International Archives of Medicine. Media outlets around the world picked it up: “Chocolate Helps You Lose Weight!”

Seems straightforward, right? Well, the "scientist" who wrote it, John Bohannon, is actually a journalist who conducted a majorly flawed study in order to prove how blindly most of us trust every study we see.

Now, chocolate may actually help with weight loss. Delicious foods can be good for you. But if you're going to rely on a study to inform your eating decisions, it's important to click through the grabby headline and examine how the study was done. How big was it? How many people were studied? What did scientists control for? Who funded it?

Below are some of the foods we all love — think avocados, coffee, and red wine — and a slightly more in-depth look at the recent studies that give us an excuse to enjoy them, as always, in moderation. (Everything in moderation.)

They could be good for your heart. New research published in the Journal of the American Heart Association has found that, by lowering bad cholesterol (aka LDL), avocados could improve heart health. The study was funded by the Hass Avocado Board and included only 45 participants, but it sheds light on the positive effect of the healthy fat in avocados on cholesterol and gives us a reason to keep eating our favorite savory fruit. (But let’s not overdo it — they’re still pretty caloric.)

They could hold the key to curing leukemia. Professor Paul Spagnuolo from the University of Waterloo has discovered a lipid in avocados that attacks leukemia stem cells directly, without harming healthy cells, but the drug is still years away from becoming approved for use in cancer patients.

They could cheer you up. We already know that fermented foods are good for your gut health, but there has been a lot of research lately that suggests they could also affect your mental health. A study from the Leiden Institute of Brain and Cognition, though small (only 40 subjects), found that people spend less time dwelling on bad feelings and experiences from the past after consuming probiotics for four weeks.

They could reduce social anxiety. A team of psychologists surveyed about 700 college students on their eating and exercise habits and personalities, and found that among people who described themselves as anxious, those who ate probiotics reported more social behavior.

It could help fight cancer. People are always saying that they need to "cut down on the coffee,” as if it’s a habit comparable to smoking, but scientists are all pretty much in agreement that it just isn’t bad for you. In fact, a meta-analysis of 40 studies on the relationship between coffee and different kinds of cancer found that coffee consumption is inversely associated with the risk of many different types of cancer — including in the bladder, breast, throat, pancreas, and prostate.

It could be good for your heart. Research by the American Heart Association showed that higher levels of coffee drinking meant a lower risk of stroke. And another study from Kyoto University showed a reduced risk of death from cardiovascular disease in people who had at least one cup o’ joe a day.

It could help men’s sex life. A new study from the University of Texas found that a few cups a day (two to three) could help lower men's risk for erectile dysfunction, because, they think, caffeine helps relax muscles and arteries, improving blood flow to the area in question.

It could be good for your heart. Or it’s just not bad for it. According to a study from the BMJ, eating up to 100 grams (or a bar) of chocolate every day is linked to lowered heart disease and stroke risk. But it could just be that those with a higher risk for cardiovascular disease eat less chocolate than those who are healthier.

It could be better for your brain than exercise … but, unfortunately, not for the rest of your body. A study from Columbia University and NYU found that those who ate a lot of chocolate — to be specific, 100 grams of cocoa powder (which usually contains 100 milligrams of flavanols) — scored better on memory tests than those who ate a little. That sounds great, but to get that much nutrition from regular chocolate, you'd have to eat 44 pounds a day … and would you really want to eat that much, even if you could? Probably not.

It could help you burn fat. Many studies have shown evidence that red wine may reduce heart disease risk (but increases risk if you overdo it) and that, as a fermented food, it may have gut (and potentially mind) benefits. But a recent study in the Journal of Nutritional Biochemistry suggests that it may have fat-busting properties, too. (But maybe just in mice.) If it helped them better metabolize fat and sugar, maybe it could help us do the same? We’ll see.

They could extend your life. A large study from Maastricht University found that those who ate about 10 grams of nuts every day were 23% more likely to avoid death from heart attacks, diabetes, respiratory failure, and even cancer, compared to those who ate less. But eating more than 15 grams per day didn't seem help any more than 10 did, so no need to go nuts (ha ha). And no, peanut butter doesn’t count.

They could help you better absorb nutrients. If you have a choice, always put an egg (or two!) on top of your salad. Aside from obviously aiding the dish’s flavor, it also helps your body better absorb the vegetables’ nutrients, according to a new study published in the American Journal of Clinical Nutrition. And don’t skip the yolk. Never skip the yolk. Its fat is what creates this effect.

So, as you can see, there are a whole lot of coulds. None of these claims are definitively proven, but they are important nonetheless. They pique our interest in scientific happenings and encourage scientists to figure out what actually causes what.

But for now, why don’t you make yourself a cup of coffee, make an avocado salad topped with pickled red cabbage, crushed nuts, and a couple eggs, and follow that with a dessert of chocolate and red wine — or don’t. That’s up to you.