And coffee is far from the only example, which makes it impossible to take any health news seriously. If you're wondering why nutrition is such a tough nut for us to crack and why people have no idea what to think about obesity , it's because ...

Nutrition is one of the most frustrating sciences in that it is arguably the most important to our daily lives, but we barely know diddly tits about it. Knowing what foods are good for us and which ones will kill us instantly seems like the type of thing we'd invest more serious energy into decoding, but "healthy" and "unhealthy" foods trade places more often than pro wrestlers in a tag-team match. Take coffee for example : First it was good for you, then it was bad, then it was good again, then it caused cancer, and then it cured cancer.

6 Our Methods For Studying Nutrition Are Terrible

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To know how different foods affect different people, we first have to know exactly what food people eat, and in what quantities, combinations, positions, etc. If this sounds like the sort of thing that is impossible to accurately observe without planting hidden cameras everywhere in the world, that's because it is. Fortunately, scientists devised something called "memory-based dietary assessment methods" (M-BMs), which is another way of saying "we ask people about their diet and then take them at their word."

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That would explain why in the '70s obesity was blamed on eating

"like ... salads? Yeah, super healthy salads and shit, man."

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Unsurprisingly, when the scientists over at the Mayo Clinic looked into the M-BM, they found that the method was "fundamentally and fatally flawed" when it came to studying nutrition. They tried to be tactful and diplomatic about their findings by attributing the failings of the M-BM to the unreliable nature of human memory, but as anyone who has ever eaten anything in their lives can tell you, it isn't hard to remember whether you eat steamed vegetables or Taco Bell on a regular basis. No, the reason the M-BM doesn't work as an accurate representation of people's diets is because people are filthy fucking liars.

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We lie all the freaking time, which is why a review of nutrition surveys found that 67.3 percent of women and 58.7 percent of men report calorie intakes that are "not physiologically plausible." And this is the data on which we base all of our food policy and dietary guidelines. Shit, maybe the fact that Big Macs are considered unhealthy is because the only ones to ever admit to eating them were depressed people on their way to kill themselves.

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"Two all-beef patties, special sauce, an entire bottle of crushed-up sleeping pills, lettuce, cheese, pickles, onions on a sesame seed bun ..."

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With such shoddy information, you can find studies linking almost any nutrient to almost any affliction you can imagine. So what we're really saying is: Remember that study that linked eating processed meat to cancer? We wouldn't let that stop you from eating bacon just yet. Speaking of which ...