S.McQuillan
Source: S.McQuillan

If you’ve ever wondered why it’s so hard to resist sweets, the answer is easy: you were born with a “sweet tooth.” Humans have an innate preference for sweet foods because our brains need sugar to function properly, our bodies use sugar most efficiently to create the energy we need to live, and our individual genes are coded to be more or less sensitive to certain tastes, sugar included. If you have low sensitivity to sweets, you are likely to need more to feel satisfied. Add to that, any childhood experience you had that conditioned you to favor sugary foods, and it’s no wonder you can’t ignore the dessert cart.

What’s worse for some of us is that we especially like sweetened, fatty foods like cakes, ice cream and chocolate, because while sugar enhances the flavor of these foods, fat gives them a pleasant texture or "mouth feel." The combination can be irresistible and, for some people, addictive.

For anyone who is able to control the amount of sugary foods in their diets, and enjoy small amounts in the context of an otherwise healthful diet, this is not a problem. But for others, sugar and sugar-fat cravings can ultimately lead to weight gain, obesity, and increased risk of developing chronic health conditions, such as diabetes and heart disease.

Is it an Addiction?

Some studies have shown that sugar causes the same chemical changes in the brain that occur with the use of addictive substances. In other words, sugar releases naturally occurring opiates in the brain, such as endorphins that produce feelings of fulfillment and contentment. Eating sugar also causes the release of chemical messengers like dopamine, a neurochemical that motivates us to search for food. At the same time, too much sugar can block the production of serotonin, a brain chemical that normally reigns in dopamine and prevents us from overeating. For some, this is a seemingly unstoppable cycle; it's no wonder they feel they are addicted to food.

Some people battle sugar cravings the way a drug addict struggles with methamphetamine, or a gambler approaches a horse race; they have to stay away altogether, or they will go on a binge. Giving in and eating sugary foods usually only result in cravings for more.

No one has ever been able to prove beyond a doubt that humans can actually become addicted to any food but, by standards many experts and certainly most self-described food addicts would find both acceptable and applicable, sugar has been shown to be highly addictive. Certainly, addictive behavior has been demonstrated again and again, both clinically by lab rats fed pure sugar and anecdotally by humans with especially bad eating habits. Just as there can be a huge difference between a social drinker and an alcoholic, there is a difference between someone who enjoys a sweet dessert after dinner and a compulsive overeater who repeatedly scarfs down enough rocky road to feed eight people.

Brain Changes

Early research with rats showed that when the animals are allowed to binge on sugar, and then are deprived of the substance, they develop more receptors for pleasure-inducing chemicals in an area of the brain that motivates eating behavior. That means it makes them feel better to eat more sugar, or to put it another way, they need to eat more sugar in order to feel good. When those receptors were blocked, the rats showed all the typical signs of withdrawal in a human, such as chattering teeth and changes in brain chemistry common to anyone who is deprived of a chemical on which they've become dependent. At the same time, rats that maintained a steady diet that included sugar syrup showed none of these signs.

In later studies, changes in the brain function of rats who went through a period of withdrawal after a month of sugar binges showed that the animals were willing to work harder to satisfy their sugar cravings, ate more sugar and, while in withdrawal, were more sensitive to other substances of abuse, such as alcohol or nicotine. Addiction can have long-lasting effects on the brain that cause, an addict to have an increased sensitivity to other addictive substances.

The Bottom Line

In addition to genes, natural preferences, and brain changes, there are other factors that encourage us to eat lots of sugar, including the social pressure to eat with others as well as emotional problems and stress that drive us to seek out rewards. We know that messages of craving, hunger, and fullness are communicated from the control center in your gut to your brain, and back again but the process isn’t fully understood. These signals may help drive our preference toward sweetened foods. While any or all of these may play a role in how you handle a sugar craving, one thing appears to be true: There is no single reason why you crave sugary foods, or why you repeatedly cave in to those cravings.

Resisting Sugar Cravings

If you routinely overeat sugary foods and want to try to break the habit, some of these tips may help:

  • Distract yourself until the craving goes away. For most people, that takes 15 to 20 minutes. Go for a walk or keep yourself busy with some other activity besides eating.
  • Schedule and eat three balanced meals a day within four or five hours of each other. Make sure you are eating enough food at each meal. If your cravings are due to real hunger, this might reduce your craving's frequency and intensity. If necessary, supplement these meals with planned snacks. If your meals and snacks provide a good balance of carbs, protein, and fat, you may be able to avoid or diminish chemical changes in the brain that stimulate cravings.
  • Usually, it’s random eating, not planned eating, that gets us in trouble. If you can control the amount you eat, include a small portion of sweets in an otherwise balanced and complete meal or snack. This may help you to avoid random sweet-eating later on in the day. (Note: This technique alone probably won’t work for anyone who binges or overeats for emotional reasons.)
  • If you feel your cravings and cave-ins are associated with emotional overeating, take steps, including psychological counseling, if necessary, to get to the root of the problem and resolve your underlying issues.

References:

Avena NM, Rada P, Hoebel BG. "Evidence for Sugar Addiction: Behavioral and Neurochemical Effects of Intermittent, Excessive Sugar Intake." Neuroscience & Behavioral Reviews. 2008;32(1): 20-39.

Avena NM, Long KA, Hoebel BG. "Sugar-Dependent Rats Show Enhanced Responding for Sugar After Abstinence: Evidence of a Sugar Deprivation Effect." Physiology & Behavior 2005;84(3):359-362.

Dias AG and El-Sohemy A. "Genetic Variation in TAS1R2 Taste Receptor and Sweet Taste Perception and Sugar Intake." FASEB April 2012;26:633.7

Sandrini S, Aldriwesh M, Airuways M, Freestone P. "Microbial Endocrinology: Host-Bacteria Communication With the Gut Microbiome." J Endocrinology 2015; 225:R21-R34.

Yanovski S. "Sugar and Fat: Cravings and Aversions." JN 2003;133(3): 8355-8375.

Updated: March 14, 2016