Carolina Cawthon, a PhD student in Foods and Nutrition department at the University of Georgia, recently gave a seminar on food addiction. Ms. Cawthon’s talk shed some light on the debate about whether or not food addiction is an actual addiction. During her talk, she covered how our brains make decisions about food, what addiction is, and the evidence we have concerning the addictive capabilities of foods in animals and humans. Understanding food addiction is important area in the arena of public health because it is a topic that is impacted by the design of our food system and the availability of “addictive” foods, as well as policy surrounding taxation of such foods.
Our food intake is regulated by many things, including stretch receptors in our stomachs (sense the amount of food that is being taken in) and hormones (send signals to our brains about hunger and fullness). The decision-making portion of our brain, which decides to eat or not eat a food, is influenced by both reasoning and reward areas of the brain. The reasoning areas operate by objectively analyzing how much we have eaten already and how hungry or full we feel. The reward areas of the brain send messages related to anticipation of how good it will feel to eat something.
Addiction is an illness in which an individual is dependent on a substance and seeks it out to avoid distress (withdrawals, anxiety, etc.). The individual continues to use the substance in spite of consequences and has a high level of motivation to obtain the substance. Use of the substance becomes a compulsion. In the physiologic state of dependence on a substance (like drugs or alcohol), the individual’s body adapts so that they need more of the substance to achieve the desired effects.
Scientists have used rats to study addiction related to food and drugs. They have found that rats become addicted to substances at rates comparable to humans and thus are useful in addiction studies. Researchers have found that rats with more impulsive traits are more likely to demonstrate addicted behaviors in relation to food intake, especially when offered a diet high in fat and sugar.
The Yale Food Addiction Scale is a tool used to measure food addiction traits in human subjects. Brain imaging data has revealed that individuals with higher scores using this scale (indicating food addiction) have higher anticipation for food and lower reward after receiving the anticipated food. This aligns with the classic attributes of addiction- heightened desire for a substance but lower satisfaction after receiving it. Researchers have used this scale to identify individuals with a greater risk for food addiction to be: women, overweight or obese, over 35 years of age, and with a previous history of disordered eating. Dopamine is a neurotransmitter involved in the brain’s reward system. Some research has shown that individuals with higher BMIs have lower densities of dopamine receptors, which support hypothesis overweight or obese individuals could feel less rewarded by food and thus eat more to compensate. So we have some data that points to the addictive capabilities of food. However, a complicating factor is that while alcohol and drug addicts can be advised to stop using the substances completely, people need food to live and thus could never be advised to stop eating.
Even though great strides are being made in food addiction research, it is not entirely clear whether food addiction is the same type of illness as drug or alcohol addiction. There is no consensus among professionals about the validity of food addiction yet. Given the rise of obesity in our nation and the detriment it is to health, a better understanding of food addiction and its characteristics will continue to be important to the success of public health efforts.
This topic of food addiction is very interesting. What is the debate regarding the validity of food addiction exactly? Based off of the definition provided above, it seems that it is a growing and serious concern. The areas of the brain that activated that causes the cravings or addictions are similar to those of drug addiction correct? I also wonder if any of the debate in this topic occurs because of poorly defined definitions and criteria for other eating disorders? Was this concern brought up during the presentation? If not, what are your thoughts on this?
I was also at this talk and I really enjoyed it! Your synopsis was thorough and intelligent and your insight about its relevance to the obesity epidemic in this country is spot on. I was wondering if you could elaborate on your comment about “addictive foods”. I know one of the rodent studies Ms. Cawthon spoke about involved comparing cocaine to sweetened water, but other than that she didn’t seem to mention specific foods or food groups. Have there been studies conducted on more “addictive” foods or drinks? I know a lot of the focus in the field of nutrition, especially with regards to obesity, is on sugar, but has there been research devoted to that question? Ms. Cawthon concluded that there wasn’t enough empirical evidence to justify the way the media uses the phrase “food addiction”. Do you agree with that assessment? And how does the point you made about food being a necessity to live, as opposed to a substance like alcohol, fit into that assessment?
Hey Carly, thanks for your comment. There is evidence to show that diets high in fat, often called “highly palatable diets” in the research, are addictive to rodents. The rodents will overeat and gain weight when on these diets. There is also research on “cafeteria diets,” where the researchers create a blend of foods high in fat and sugar (think peanut butter blended with marshmallows and potato chips) and observe the rodents’ eating patterns and weight gain. The animal research supports that when given access to high fat and high sugar foods, the animals will overeat and gain weight.
I agree with Ms. Cawthon’s sentiment that we do not have enough evidence to classify food addiction as a classical addiction. “Undesirable food habits” may be a better description for what we currently refer to as food addiction. The person making undesirable food choices still needs food, but the choices they are making need to be adjusted to better suit their nutrient needs and weight goals.
I think a large part of the problem facing Americans trying to make healthful food choices is the lack of a supportive environment for that pursuit. The food industry spends exorbitant amounts of money on advertising as well as research and development to make foods more palatable. A lot of time more palatable means more fat and more sugar. If junk food was not as readily available, as Ms. Cawthon mentioned, then we may see improvements in Americans’ food choices.
Hannah, thanks for letting me know about that research with rodents. That’s super interesting and makes sense with what we know anecdotally about people’s eating habits and obesity. I like the term “undesirable food habits” instead of food addiction. This seems like a dumb or obvious question but why are companies so focused on advertising more palatable foods or selling more palatable foods? It must be cheaper…it’s certainly cheaper to sell unhealthier food than healthier food. But I would think that companies that make healthy/organic foods make more money since they charge a lot more for their food.
Great question… I don’t think I have the appropriate economics or consumer behavior background to give you a really good answer to that. My best guess is that when a company creates a highly palatable food, consumer satisfaction and demand for that product will increase. It makes sense that it is in the food company’s best interest to make their products as tasty as possible.
Health foods or organic companies do have a lot of expensive products. I think one reason they can get away with it because health conscious consumers may also be of better socioeconomic status and have to purchasing power to obtain those expensive products. Take granola for example. An unhealthy bag of granola (full of sugar) is cheap relative to a healthier variety that is low in sugar. You are essentially paying the food company more to leave the sugar out! On the bright side, making you own low-sugar granola at home can be cheaper than both of the pre-made options. This obviously requires more time, effort, and cooking space, however.