Idiom:
Long face ( look serious )

Hit the book:
So is it good or bad to eat the same stuff every day? If you're thinking a bagel for breakfast, sandwich for lunch, and meat with potatoes and a salad for dinner, you're surely going to be deficient in a number of the necessary nutrients your body needs to thrive, Roberts says.
But if you're packing plenty of healthful, micronutrient-dense vegetables into your simple meal plan—at least six, Roberts advises—you probably don't have much to worry about. Just be sure the vegetables you eat come in lots of colors, which tend to correlate with different nutrients. And stay away from starchy vegetables like potatoes, which don't offer a lot of nutrient bang for your buck, she adds.