We are talking this month about the main reasons why we are overweight: a combination of overhunger, overdesire, and emotional or habit eating. I’m breaking it all down into bite-sized nuggets for your consumption, and we have already touched on the first 4 ways that you can make a real dent in your physical hunger: limiting sugars and refined grains, adding in more protein, avoiding liquid calories, and sleeping better.
Today we talk about calorie density. It turns out that human beings seem to eat about the same total weight of food each day: approximately 4 pounds. When we approach 4 pounds of food, we feel pretty satisfied. If you think about the density of calories in the foods we eat, one end of the spectrum contains very low calorie-dense foods like nonstarchy veggies or fresh fruit — whole foods that are high in water and fiber content. Water and fiber have no usable energy (no calories) but take up space and weigh a lot. On the other end of the spectrum are processed grains with little or no water in them (think crackers, pretzels, or PopTarts) and high fat foods, because fat has more than double the calories per gram than protein and carbs/sugar do. This means that eating a pound of raw celery, or approximately 11 stalks (which has a low calorie density due to its high water and fiber content) will provide you with 63 calories, whereas eating a pound of cheddar cheese (high calorie density due to being high in fat with no fiber and very little water) will provide you with a whopping 1,826 calories. The celery takes up a lot more space and stretches out your stomach, which by itself has a positive effect on satiety, in addition to providing fewer calories per pound. So you can see why, if you are going to eat 4 pounds of food every day, eating a diet high in processed, calorie-dense foods like Doritos, breakfast cereal, burgers or candy bars can add up to waaaay more calories pound-for-pound compared to an unprocessed diet full of water- and fiber-rich whole foods like vegetables, fresh fruit, beans, seafood and leaner meats.
Proving this point is one of my my favorite research studies: this one published by Kevin Hall and colleagues at the NIH, in which they found that people naturally ate more than 500 extra calories every day and gained a pound a week when eating processed foods. Bottom line: eat more plants to bulk up your diet’s water and fiber content and get fewer calories while staying satisfied!