How Cravings Can Derail Your Diet

It's not only your stomach that desires a certain food, it's also your head. Cravings have biological and psychological roots: Learning to control those urges can help your diet.

Why do you crave chocolate in the middle of the afternoon while your husband craves steak at the end of the day? Why do pregnant women have peculiar cravings and why do women crave more carbs in the days prior to their period? These and other questions plague people who want to maintain a healthy diet, yet feel undermined by their own body’s insistent demands for off-limits foods.

Cravings: The Driving Forces
Cravings — defined as “an intense desire to eat a certain food” — are both psychological and biological. "It's definitely a mixture,” says nutrition researcher Susan B. Roberts, PhD, a senior scientist at Tufts University in Medford, Mass.
Researchers have proposed various theories to explain why just about everyone struggles with cravings:

• Your body learns, over time and exposure, that certain foods trigger a positive response. That’s why you continue to crave the “comfort foods" you grew up with.
• Some foods may trigger a neuro-chemical response that releases pleasure hormones, such as dopamine, after eating them.
• The sight or thought of certain foods causes another chemical cascade that compels you to believe the food in question will be very tasty (which is a good argument for keeping the foods you crave out of sight!)
• Your diet may lack variety, which causes you to want a change.
• You may need some nutrient or component of the food that your diet is lacking.
• Your diet lacks your favorite foods, and you miss them.
• You’re hungry.

Cravings: The Diet Impact
The impact of cravings on a set diet has been widely researched. Roberts and colleagues studied food cravings and behavior reported by 32 adult women participating in a six-month low-calorie diet. They learned that:

• A person’s highest weight over her lifetime was related to the amount she ate when she gave in to cravings: the greater her weight had ever been, the more she ate.
• People who were less active tended to crave fattier foods.
• The most commonly craved foods were about twice as calorie-dense as the person’s prescribed diet foods and 30 percent higher in fat, while being 50 percent lower in protein and 30 percent lower in fiber.
• Craved foods tended to be a mix of carbohydrates and fats, which Roberts argues may double the pleasure in terms of the body’s reward system.
• Chocolate was the most commonly craved food, followed by salty snacks.
• People who successfully lost weight on the diet had just as many cravings for high-calorie foods as their peers, but they gave in to them a lot less often.

The take-home message: People who want to lose weight should accept the fact that cravings will happen while they are dieting. Once they have reached their weight-loss goals, they need to develop a strategy to give in to cravings on a limited basis and in a portion-controlled manner.
Cravings: Women vs. Men
Everyone has his or her own special weakness, but cravings do tend to break down along gender lines and seasons of life.
“Women tend to crave sweet stuff — chocolate, candy, cookies. Men tend to crave steak, chips, salty stuff,” says Roberts, who has authored a diet book based on managing cravings, The Instinct Diet: Use Your Five Food Instincts to Lose Weight and Keep it Off. “Pregnant women have cravings that are all over the map, up to and including pica — eating things like clay — occasionally. We don't know why there is a difference between men and women; research hasn't gotten that far yet.”
Scientists continue to examine the relationship between cravings and weight loss (or gain), but in the meantime, experts like Roberts recommend accepting the universal nature of cravings. Work with them instead of trying to suppress them