The mistake:
Thinking "eyeballing" is a valid form of measurement

How it hurts: It's easy to over-indulge in the staples of this diet, like olive oil and (especially) wine. And if you're not accurately measuring your portion sizes, the calories add up quickly -- especially for olive oil, which can add hundreds of excess calories to your meals, says Sheth. Plus, Sass says that since wine is an appetite stimulant, overdoing it on the Pinot can make you more prone to overeating (especially if you're trying to eyeball other food measurements). It can also make you more likely to indulge in foods you would steer clear of if you were a little less tipsy (like, say, Taco Bell or your hidden stash of treats).

The fix: The recommended daily amount of wine is no more that one five-ounce glass for women. And before you even ask, no, those glasses you didn't drink Monday through Thursday don't roll over to the weekend, says Sass. As for the olive oil -- always use a measuring spoon instead of just drizzling it over your salad or pouring it directly into your pain, recommends Sheth.