Diet crazes come and go, says Ellen Tarlin in Slate, but each new fad only makes it harder to figure out what we really should be eating. One year, we're told to drink eight glasses of water a day. "Then, after drowning ourselves in the stuff, we are told, no, sorry, not true anymore. Sugar is bad! Fats make you fat! No, actually carbs do! No, only bad carbs! Fats are good for you again!" We're "inundated" with "overwhelming, inconsistent," and "inaccurate" advice. Maybe the trick is finding some "common denominators" that experts agree are good for you, such as whole grains and lean proteins. Fad diets — remember Atkins? — are confusing. The information on the merits of healthy food staples "has been fairly consistent for the last 50 years, if not longer." Here, an excerpt:

"I thought about the diets I'd been on. Why were they all so different? Was there any meal in the world that would adhere to the rules of all diets? I tried to come up with the healthiest meal I could think of: perhaps grilled salmon with brown rice and dark leafy greens like kale or chard. No, salmon would not be acceptable to vegans and some vegetarians; rice wouldn't work on Atkins. That left greens. Was there at least one food that would fit into all diets? It had to be greens: The one food I never crave and have to force-feed myself."

Read the full article in Slate.