By James J. DiNicolantonio and Sean C. Lucan
December 22, 2014
New York Times
YOUR co-worker brought in brownies, your daughter made cookies for a holiday party and candy is arriving from far-flung relatives. Sugar is everywhere. It is celebration, it is festivity, it is love.
It’s also dangerous. In a recent study, we showed that sugar, perhaps more than salt, contributes to the development of cardiovascular disease. Evidence is growing, too, that eating too much sugar can lead to fatty liver disease, hypertension, Type 2 diabetes, obesity and kidney disease.
Yet people can’t resist. And the reason for that is pretty simple. Sugar is addictive. And we don’t mean addictive in that way that people talk about delicious foods. We mean addictive, literally, in the same way as drugs. And the food industry is doing everything it can to keep us hooked.
Up until just a few hundred years ago, concentrated sugars were essentially absent from the human diet — besides, perhaps, the fortuitous find of small quantities of wild honey. Sugar would have been a rare source of energy in the environment, and strong cravings for it would have benefited human survival. Sugar cravings would have prompted searches for sweet foods, the kind that help us layer on fat and store energy for times of scarcity.
Today added sugar is everywhere, used in approximately 75 percent of packaged foods purchased in the United States. The average American consumes anywhere from a quarter to a half pound of sugar a day. If you consider that the added sugar in a single can of soda might be more than most people would have consumed in an entire year, just a few hundred years ago, you get a sense of how dramatically our environment has changed. The sweet craving that once offered a survival advantage now works against us.
Whereas natural sugar sources like whole fruits and vegetables are generally not very concentrated because the sweetness is buffered by water, fiber and other constituents, modern industrial sugar sources are unnaturally potent and quickly provide a big hit. Natural whole foods like beets are stripped of their water, fiber, vitamins, minerals and all other beneficial components to produce purified sweetness. All that’s left are pure, white, sugary crystals.
A comparison to drugs would not be misplaced here. Similar refinement processes transform other plants like poppies and coca into heroin and cocaine. Refined sugars also affect people’s bodies and brains.
Substance use disorders, defined by the Diagnostic and Statistical Manual of Mental Disorders, exist when at least two to three symptoms from a list of 11 are present. In animal models, sugar produces at least three symptoms consistent with substance abuse and dependence: cravings, tolerance and withdrawal. Other druglike properties of sugar include (but are not limited to) cross-sensitization, cross-tolerance, cross-dependence, reward, opioid effects and other neurochemical changes in the brain. In animal studies, animals experience sugar like a drug and can become sugar-addicted. One study has shown that if given the choice, rats will choose sugar over cocaine in lab settings because the reward is greater; the “high” is more pleasurable.
In humans, the situation may not be very different. Sugar stimulates brain pathways just as an opioid would, and sugar has been found to be habit-forming in people. Cravings induced by sugar are comparable to those induced by addictive drugs like cocaine and nicotine. And although other food components may also be pleasurable, sugar may be uniquely addictive in the food world. For instance, functional M.R.I. tests involving milkshakes demonstrate that it’s the sugar, not the fat, that people crave. Sugar is added to foods by an industry whose goal is to engineer products to be as irresistible and addictive as possible. How can we kick this habit? One route is to make foods and drinks with added sugar more expensive, through higher taxes. Another would be to remove sugar-sweetened beverages from places like schools and hospitals or to regulate sugar-added products just as we do alcohol and tobacco, for instance, by putting restrictions on advertising and by slapping on warning labels.
But as we suggested in two academic papers, one on salt and sugar in the journal Open Heart and the other on sugar and calories in Public Health Nutrition, focusing narrowly on added sugar could have unintended consequences. It could prompt the food industry to inject something equally or more harmful into processed foods, as an alternative.
A better approach to sugar rehab is to promote the consumption of whole, natural foods. Substituting whole foods for sweet industrial concoctions may be a hard sell, but in the face of an industry that is exploiting our biological nature to keep us addicted, it may be the best solution for those who need that sugar fix.