In researching this article, I discovered that the subject of addiction is often a controversial one. There are many scientists who, based on their research, feel that many forms of addiction are either caused by or related to a form of allergic reaction. That is, the substances that we are addicted to cause a reaction in the body (often including increased production of histamines) that has the psychological side effect of causing us to crave the very substances we are allergic to. This opinion is often countered – angrily, defensively, and sometimes surprisingly – by those promoting addiction recovery programs. They don't like the idea that addiction is "caused" by anything outside our control, because their programs are based on the idea that one can use willpower and group support to overcome addictions. There are arguments to be made for both sides of this issue, and there is as yet no incontrovertible evidence that either side is more "right" than the other. I tend to believe that while there may, in fact be systemic triggers for addictive behavior, individuals can learn to overcome those triggers.
And that's a good thing, because recent research on the nature of addiction is not about heroin or alcohol or cocaine or nicotine, but about food. Many of the foods that nutritionists agree are bad for us – too much sugar, highly refined foods like white flour, and high-fat, high-calorie junk foods – do tend to trigger reactions in the brains and bodies that resemble those caused by cocaine and other substances that everyone agrees are addictive.
The argument for certain foods being addicting
One of the most striking "food can be addictive" studies was published in 2010 in the journal Nature Neuroscience, and was based on rat studies. The diets of three groups of rats was controlled for a period of 40 days – one third was fed rat food as usual, another third was fed cheesecake, frosting, bacon, sausage, and other high-fat, high-calorie foods only for one hour a day, while the final third was allowed to eat the junk food any time they wanted. Unsurprisingly, the second and third groups of rats became more obese. But the third group also began to show classic addictive behavior – they ate compulsively, even when doing so was rendered painful as the result of electric shocks being given to them. The researchers theorized that the processed and refined foods the rats were eating were affecting their brains more powerfully, in much the same way that refined cocaine affects humans more powerfully than the raw coca leaves it is extracted from. The junk food was triggering higher dopamine levels in the rats' brains that were compelling them to eat more as a form of pleasure.
Another rat study exposed the animals to high levels of sugar, with the expected result that the rats quickly seemed to become addicted to it. When the sugar was removed from their diet, they displayed signs of opiate-like withdrawal symptoms – tremors, chattering teeth, and shaking. When some of the rats were allowed to resume eating sugar two weeks later, they began pressing the food bar that dispensed it frantically, consuming 23% more sugar than before.
Scientists at the Oregon Research Institute replicated these results to some extent in humans by scanning the brains of subjects showed photographs of chocolate milk shakes, and then consuming them. They found that the subjects developed a growing "tolerance," similar to the way that drug users need more and more of a drug to get high. The regular ice cream eaters began to require more and more ice cream to achieve the feeling of being satisfied, and for the reward centers of their brains to acknowledge that they'd "had enough."
What does this mean to those of us who are dieting?
At present, as noted above, what it doesn't mean is that you have no power or control over your cravings for certain foods. Yes, some of these foods do indeed seem to have an addictive "trigger effect" that causes our brains and our bodies to crave more of them, even though we know they're bad for us. But at the same time, people are often able to overcome these cravings, and re-train themselves to avoid the addicting foods and substitute other foods that are better for them.
Some nutrition research has applied the methodology of addiction withdrawal to dieting. For dieters with a noted preference (if not addiction) to sugar, for example, they often were able to substitute a more healthy fruit smoothie for the ice cream they craved, similar to how recovering heroin addicts utilize methadone. In 2011, the huge field of obesity research received over six million dollars of funding from the National Institute on Drug Abuse, to look into this very issue of whether obesity is in some ways the result of addictive behavior. Many who feel that certain foods are addictive are beginning to call for warning labels to be required for certain junk foods and processed foodstuffs, similar to the labels currently required for cigarettes.
Whether this theory that certain foods are actually addictive is validated or not, those of us on diets or trying to maintain a healthy weight can still gain some comfort from the many people who have faced stronger addictions and conquered them. If a heroin addict can learn to resist his cravings for that drug, then we can resist ours for an extra helping of bacon or a milk shake.