Food and dieters have a love-hate relationship. Beyond being an essential fuel source, food is comforting, exhilarating to the taste buds and even influences your brain.
Some scientists believe that food alters your brain enough to be considered an addictive substance; and neurological and addiction research is growing in support of this belief.
According to Neal Barnard, M.D., author of Breaking the Food Seduction, some foods can be as addicting as drugs. He asserts that opiates in certain foods — cheese, chocolate and sugar — lead to an insatiable craving similar to that which a person addicted to drugs experiences. For example, chocolate stimulates opiate receptors in the brain, while sugar initiates the release of opiates.
The body naturally produces opiate-like chemicals to regulate mood, pain, hunger, thirst and other vital processes. Barnard explains that foods that contain opiates can trigger a feeling of euphoria, which entices us to crave and eat more of them.
Barnard says that the major protein found in dairy products, casein, contains minute amounts of morphine as a way to ensure a baby calf bonds with its mother. The more concentrated a dairy product, the more casein is has, and therefore the more addictive — cheese contains the highest concentration of casein among all dairy products. According to Barnard, casein fragments during the digestive process, which produces copious amounts of natural opiates called casomorphins.
Both drugs and some foods have the remarkable ability to elevate levels of the neurotransmitter dopamine — a chemical messenger associated with feelings of pleasure and elation and involved in brain signals that play a role in food intake.
Studies have concluded that the same areas of the brain are involved in drug and food cravings. Indeed, it is dopamine that triggers a drug-induced high.
A glutamate receptor on dopamine neurons, known as the NMDA receptor, is essential to habit formation according to research conducted by Georgia Health Sciences in 2011. During the study, scientists discovered that selectively disabling the NMDA receptor in mice prevented the mice from habitually pushing a lever to dispense food. On the contrary, mice with the NMDA receptor pushed the lever uncontrollably despite being full.
A 1991 University of Michigan study found that administering naloxone — a drug used to block narcotics from affecting the brain — significantly reduced sweet and high-fat food consumption among binge eaters. The study findings suggest that blocking opiate receptors reduces the pleasurable sensation and appeal of opiate-containing foods.
The key appears to be the proper balance of neurotransmitters in the brain. The more balanced your levels are, the less likely you are to become addicted. Conversely, the more out of balance your neurotransmitter levels the more likely you are to have food cravings and dependences.
While foods that are appetizing and pleasing to the taste can increase consumption in the short term, it is unlikely that palatability is what causes addiction. Food cravings may also be a learned behavior from factors such as environmental cues, the way it is consumed, social norms, habits and restrictive dietary patterns.
Overeating can become a mindless and automatic habit, as was the case in a 2011 study by the American Psychological Association. Moviegoers who were given an extra-large tub of popcorn ate more while watching a movie, even though the popcorn they received was stale.
Other studies have demonstrated eating patterns can be modified by eating with your non-dominant hand, eating next to someone who overeats and watching TV while eating.
Restrictive eating may also contribute to food addictions. Any time you remove a particular food or food group from your diet completely, your brain sends craving signals for that food, which often results in over-indulging. The greater the restriction and the longer the restriction lasts the more intense the cravings will be.
Being aware of the addictive potential of food is essential to successful weight management.