In simple terms, every piece of food we put in our mouths counts. But three common myths beaten into our brains reflect a basic misunderstanding of how calories affect our physical health and appearance.

First, advice to simply eat fewer calories and exercise more is misleading, says Jonathan Bailor, a health and nutrition expert who authored The Calorie Myth. “If you eat less and exercise more, then eat higher quality food and do higher quality exercise,” Bailor suggests. “That changes everything about the weight loss and health game.”

Second, all calories aren’t the same. Think of it this way, Bailor says: If you feed a child a soda and Twinkies, the quality of those 400 or more calories is much different than the same amount of calories that comes from a serving of non-starchy veggies, healthy fats and nutrient-dense protein. “I call these SANE foods,” Bailor says, meaning Satiating, Aggressive, Nutritious and Efficient foods that keep you full, release consistent levels of energy slowly into the bloodstream and help burn body fat instead of store it.

Third, calories aren’t the only factor to consider. “Genetics and hormones matter immensely too,” Bailor says. “We all know that if we ate the same way we did 15 or 20 years ago, we’d get different results today compared with when we were younger.”