Our cravings for fat, salt, and sugar started back when humans lived in caves and hunted and gathered for their food. Fat, salt, and sugar were in short supply. So to ensure that we ate adequate supplies of each, we evolved a craving for them.
But now we live in an environment that is brimming with food and drinks that satisfy these cravings — and, in the process, make us overweight, cause illness, and shorten our lives. An adult can get by on as little as 500 milligrams (mg) of sodium a day; the average American intake is about seven times that amount, or 3,400 mg. Humans can certainly live without sugar (and, in fact, without any kind of carbohydrate as long as some fat and protein are available), but Americans now consume, on average, about 20 teaspoons of added sugar daily — and that's above and beyond the sugars found naturally in fruit, vegetables, and dairy products.
Many people say that adopting diets low in salt, fat, sugar, or animal products alters their food preferences, and there's some scientific evidence to support this experience. Researchers have also investigated methods of modifying one's food preferences so more healthful foods will be more appealing. In general — and not unexpectedly — flavor and food preferences are more malleable when we're young (indeed, in utero), but as adults, we can still work on them.
Several studies have shown that people who manage to follow a low-sodium diet for several months wind up preferring lower concentrations of salt in their food.
Appetites for sugar and fat can also be changed, although there's less experimental evidence for it. British researchers reported results in 2011 from a small study that showed that tastes changed to liking sweeter things after a month of drinking a sweetened energy drink.
How to avoid overeating
One expert on nutrition and behavior change has developed a number of behavioral techniques for reducing ingestion of unhealthy calories. Brian Wansink, a Cornell professor and author of Mindless Eating, has identified five situations where people are particularly at risk for ingesting large quantities. He has called them "meal stuffing," "snack grazing," "restaurant indulging," "party bingeing," and "desktop or dashboard dining."
To reduce meal stuffing, Wansink suggests using a smaller plate, and serving the meal from the stove, not from the dining table. "Our research shows you eat 22% less on a 10-inch than on a 12-inch plate." To reduce snack grazing, keep the snacks at least six feet away from your desk or from wherever you are sitting. The distance forces you to think before you grab another bite, and Wansink's research shows that it can translate into a 125-calorie reduction in your daily energy intake (every little bit helps). The same distancing advice applies to party bingeing. You should also put no more than two items on your plate on any trip to the snack table and start with the bulky, low-calorie stuff — the raw vegetables.
Wansink also advises people not to try more than a couple of his techniques at one time. "We find that if people can maintain changes for a couple of months, they will then make a second, or third, or fourth change," he says.
Developing a taste for vegetables
Altering our palates so we don't like unhealthful salt and sugar is one way to go. But an alternative strategy is to increase our taste for foods that are certifiably healthful, like vegetables.
Vegetables contain bitter compounds — and some people have a genetic propensity to experience more bitterness from vegetables (as well as other foods) than other people do. Heightened bitterness can also obscure sweetness. Vegetables tend to be more palatable to more people when the bitter and sweet tastes are nicely balanced and form that complicated bittersweet experience.
If you keep an open mind and try a variety of vegetables, you might find varieties that contain bitter compounds to which you are less sensitive. You may respond more to the bitter compounds in, say, broccoli than those in kale.
Developing a taste for whole grains
According to dietary guidelines, at least half of the grain-based food we eat should be made from whole grains (and that is setting the bar too low). Most Americans don't even come close to meeting that recommendation, partly because whole grains tend to have a slightly more bitter taste and rougher texture than foods made with refined grains (think white bread).
One strategy for making whole grains more appealing is simply to mix in some refined grains. You can do this at home by substituting half the flour in cookie, muffin, or bread recipes with whole-wheat flour. Mixing wheat germ into meatballs, meatloaf, or burgers or adding barley, a whole grain that's mild in flavor, as a thickener in soups and stews are other easy ways to sneak more whole grains into your diet.
Give in to your desire — a little
Weight-loss and other kinds of diets have a long history of poor long-term success. One possible explanation — among many — is that completely excluding certain foods, and their flavors, stokes our appetites for them. Once again, moderation is a good idea.
Excessive dietary restriction can lead to bingeing. In one experiment, female dieters and nondieters were served either nothing, one milk shake, or two. Then they were asked to taste and rate some ice cream. Dieters who felt they had broken their diets responded by overeating the ice cream, regardless of whether they'd had one or two milk shakes. The nondieters did no such thing.