A new study shows that highly processed foods can be as addictive as heroin, cocaine and nicotine, leading some health experts to call for warning labels on popularly consumed snacks such as cookies and chips. The new research, which analyzed the findings of nearly 300 previous nutritional studies, was published recently by the peer-reviewed British Medical Journal.
The study was headed by University of Michigan professor Ashley Gearhardt, who previously created the Yale Food Addiction Scale (YFAS) by applying the same criteria that experts use to diagnose substance addiction, including uncontrollable and excessive consumption, cravings and continued intake despite potential negative health effects.
Although addiction to certain foods is not included in common diagnostic frameworks to assess mental health such as the Diagnostic and Statistical Manual of Mental Disorders (DSM-5), research on this topic has grown rapidly in the past 20 years. Much of this research uses the YFAS, which was developed to measure food addiction by assessing DSM-5 criteria for substance use disorder in the context of food intake.
Study Finds 14% of Adults Are Addicted to UPFs
To complete the new study, researchers reviewed 281 previous studies conducted in 36 countries, which found that 14% of adults are addicted to UPFs (ultra-processed foods). The team of researchers was alarmed by the findings because of the amount of UPFs– foods such as cookies, ice cream, sausage, and sugary soft drinks and breakfast cereals– found in modern diets.
“The combination of refined carbohydrates and fats often found in UPFs seems to have a supra-additive effect on brain reward systems, above either macronutrient alone, which may increase the addictive potential of these foods,” Gearhardt and the authors of the study wrote in their new findings.
As UPFs have become more common, previous studies have shown them to be associated with serious medical conditions including cancer, early death, cognitive decline and mental health issues.
“Many UPFs for many people are addictive,” author Chris van Tulleken told The Guardian about the new study. “And when people experience food addiction, it is almost always to UPF products.”
Exactly why UPFs cause food addictions is not yet understood. Some experts believe that rather than one particular substance being the root cause of food addictions, a combination of UPFs taken together may be the cause.
While they are “not likely addictive on their own,” food additives could be “reinforcers” of the caloric effects, the researchers wrote.
Food Addiction Similar to Drugs and Alcohol
Natural, unprocessed foods normally have more carbohydrates or more fat, but not both. However, UPFs often have disproportionately higher levels of both fats and carbohydrates. Eating UPFs triggers a spike in dopamine that is followed by a steep decline in the neurotransmitter. The result is a cycle of craving, satisfaction and crash similar to drugs and alcohol, although not everyone is susceptible.
“Addictive products are not addictive for everyone,” said van Tulleken. “Almost 90% of people can try alcohol and not develop a problematic relationship; many can try cigarettes, or even cocaine.”
Past research has also found that sugary or fatty foods make healthier alternatives less appealing, a change that could have negative consequences on health, such as over-indulging and weight gain. However, avoiding UPFs has become difficult for many people because processed foods are so ubiquitous in the modern diet. As a result, the addictive properties of UPFs have led some health-conscious researchers to recommend that many foods should come with a warning similar to those for cigarettes and other tobacco products.
“Trying to quit UPFs now is like trying to quit smoking in the 1960s,” said van Tulleken.
Luckily, most of the substances are safe when used in moderation, leading online medical resource Healthline to recommend that processed foods make up no more than 10% to 20% of the calories in a person’s diet. To help reach that goal, van Tulleken suggests choosing foods thoughtfully.
“Ask yourself: is this really food? You can quickly move from addiction to disgust,” he said.