Holding Out for Better Is How To Eat Worse

We’ve all heard from a young age that a healthy diet is eating a lot of fresh fruits and vegetables, especially green vegetables. Fresh fruits and vegetables are relatively low in calories and low in fat while being high in fiber and all kinds of essential vitamins and minerals. Fresh fruit tastes sweet but the sugar in fresh fruit is fructose, which is lower on the glycemic index (how much a food spikes your blood sugar level) than sucrose, which comes from cane sugar and is the source of much of the added sugar in our foods. Also, the sugar in fresh fruit is diluted by all that water and fiber in which it is embedded. That’s why we add sugar to fruit pies, jams, and jellies, none of which would be sweet enough without it. Why is it then that we don’t eat enough fresh fruits and vegetables if it’s so good for us? Shouldn’t our bodies possess the intuitive wisdom to fill up on such healthful foods?

The aversion to filling up on fresh fruits and vegetables emerges in early childhood. How many children love to eat their broccoli and how many children would rather eat an apple for dessert instead of apple pie? Parents find themselves in power struggles with their children from an early age to get them to eat more fresh fruits and vegetables. Often the only way parents can succeed in that endeavor is to hold dessert ransom by threatening to withhold dessert until they eat their broccoli. Children take a few nibbles of their broccoli and then demand their dessert. Clearly, these children are still hungry and have room for dessert. There is always room for dessert. Children seem to be able to hold out for better. Why fill up on broccoli when you can fill up on dessert?

Are adult food preferences really any different than children’s food preferences? We don’t want to fill up on fresh fruits and vegetables when we are holding out for better. Better is not only dessert but it’s bread and butter, it’s steak and french fries with ketchup, it’s pizza and pasta, it’s wine and beer, it’s rice and beans. All those foods seem to be a lot more satisfying and filling than fresh fruits and vegetables. It’s not that we won’t eat fresh fruits and vegetables at all, but those foods get demoted to condiments, something we eat a little bit of on the side. We eat a small side salad with our steak and french fries with ketchup, or we have a few pieces of cut up fresh fruit with our breakfast pancakes with syrup. We will happily eat relatively small portions of fresh fruits and vegetables. We just don’t want to eat a lot of it. We don’t want to fill up on it. That’s why we’re constantly being told to eat more of it.

The Evolution of Human Food Preferences

For most of human evolution, the basic problem was how to get enough calories to grow a big body and a big brain and not starve to death. We’re bigger and smarter than most monkeys and apes. We seemed to be able to accomplish that feat over millions of years of human evolution by becoming omnivores. Most of the monkeys and apes from whom we are descended are herbivores. They just eat plant food, and a gorilla can grow a large body just eating bamboo. At some point in human evolution, we started eating meat, a calorie-dense/high-fat food, and became adept at finding nuts and honey, which are also calorie-dense foods. It’s also possible that early in human evolution we learned how to make fire and figured out that we could eat starchy foods like potatoes that are high on the glycemic index by roasting them on an open fire.

The evolved human food preference might then be to fill up on, if not feast on, calorie-dense foods like fatty meat, nuts, honey, and roasted starchy plant foods whenever available and only to fill up on fresh fruits and vegetables when you must, so you don’t starve to death. In this respect, we might not be any different from our pet dogs and cats. Our pets will always prefer the higher-calorie food to the lower-calorie food. Our pets prefer human food over pet food because human food is generally more calorically dense than pet food.

The rise of civilization enabled humans to generate larger quantities of calorie-dense foods. Through farming, we could generate large quantities of carbohydrate-rich grains like wheat and rice. Through the domestication of livestock, we could generate large quantities of fatty meats and dairy. The rise of civilization is the rise of obesity because, for the first time in human evolution, we could stuff ourselves on calorie-dense foods like roasted meats, bread, fried rice, cereals, pasta, and desserts to our hearts’ content (if you were rich and could afford it). As we got better at cheaply generating calorie-dense foods like peanut butter or French fries, even poor people could become obese. These days, it’s a diet of fresh fruits and green vegetables that is expensive.

Learning to Fill Up on Fresh Fruits and Green Vegetables

If you’re overweight, it’s not because you eat too much steamed broccoli or too many strawberries. The problem is you eat too little of these. Dieting is basically eating fewer calorie-dense foods like bread, pasta, cereal, mashed potatoes with butter, fatty meats, cheese, and sweets while eating more low-calorie foods like fresh fruits and green vegetables. The difficulty with dieting is that we don’t want to do that because it goes against the instinctive tendency that emerges in early childhood to hold out for better. How do we learn to fill up on fresh fruits and vegetables when we would prefer to hold out for better?

Ultimately, evolution is about survival and reproduction. We must remind ourselves that to live to a ripe old age we have to avoid obesity-related diseases like type 2 diabetes and heart disease. We must remind ourselves that to be reproductively successful it helps to look fit and healthy. It’s not easy to fill up on fresh fruits and vegetables when you would prefer to hold out for better. Yet you might discover that as you learn to fill up on fresh fruits and vegetables you not only start to lose weight, but you feel healthier as well. Your gastrointestinal functioning improves, and you have more energy. Your old way of eating starts to seem disgusting, the calorie-dense foods begin to taste too rich and cloying. When the rewards of your new way of eating begin to outweigh all the negatives of your old way of eating, dieting becomes easier, and you are less likely to revert to your old fattening diet. So, here's a challenge: stop holding out for better. Eat your broccoli and you’ll feel a lot better about yourself.