How processed foods may lead to “food addiction” and obesity
Dr. Farrell Cahill See Bio
Dr. Farrell Cahill is a recognized leader in the field of obesity, diabetes, and exercise physiology in Canada. Through his expertise in genetics, endocrinology, and human physiology, Dr. Cahill explores the aetiology and management of both obesity and diabetes to improve occupational health and performance.Hide
Accumulating evidence has documented neurobiological and behavioural similarities between compulsive overeating and psychoactive drug dependence.
Obesity and being overweight are the fifth leading cause of global death1 and the second most preventable cause of death in the United Stated and Canada2. Weight gain in the general population is complicated. Being overweight or obese is usually the result of a complex interplay between an individual’s genetics/ biology, personal lifestyle choices, and environmental factors that lead to consuming more calories than one burns (energy surplus)3. In Canada, overeating combined with sedentary lifestyles are the main causes of weight gain and obesity in the general population4,5; however, recent research suggests that a certain proportion of the population may be afflicted with a more serious condition that predisposes them to overeating: food addiction. “Food addiction” is defined as an obsessive or compulsive relationship to certain foods 6 ; individuals that suffer from “food addiction” chronically consume more food than they need to maintain health, and show compulsive intake behaviours associated with loss of control of eating 5,7.
“Up to 1 in 20 people suffer from “food addiction” and it is an important contributing factor in the development of obesity and diabetes.”
– Dr. Cahill
Is “food addiction” real?
Whether, and to what degree, “food addiction” contributes to obesity in the general population is a subject of much debate within the obesity research community. When it comes to obesity and diabetes, you can’t say that “food addiction” is the cause, but it’s arguably a contributing factor. Weight management, once thought to simply be about the number of calories in versus number of calories out, is now recognized as a significant behavioral and physiological challenge for many people. Even people who aren’t overweight or obese can be addicted to food, or have an unhealthy relationship with food, and this relationship might make them more prone to obesity and diabetes in the future. Accumulating evidence has documented neurobiological and behavioural similarities between compulsive overeating and psychoactive drug dependence, leading researchers to use the term “food addiction” to describe this pattern of overeating8-12. “All of us have a need to eat food, but we don’t all go through symptoms of withdrawal, that’s the difference”, explains Dr. Cahill, head of employee wellness research at Medisys Corporate Health.
One study found that “food addiction” impacted 6.7% of females and 3.0% of males.
A research study co-authored by Dr. Cahill during this PhD in Dr. Guang Sun’s laboratory, a professor in the Faculty of Medicine at Memorial, shows that “food addiction” is an important contributing factor in the development of obesity. In their study, 652 adults (415 women, 237 men) were recruited from the general population in Newfoundland and Labrador (NL) Canada, and “food addiction” was assessed using the Yale Food Addiction Scale. The findings revealed that the prevalence of “food addiction” (defined as an obsessive or compulsive relationship to certain foods) was 6.7% in females and 3.0% in males and increased with obesity status. In addition, the study also demonstrated that “food addicts” were 11.7 (kg) heavier, 4.6 BMI units higher, and had 8.2% more body fat and 8.5% more trunk fat than the control subjects; suggesting that “food addiction” contributes to both the severity of obesity and body fat composition, with a higher rate in women as compared to men.
Highly processed, high-sugar foods are the most addictive.
We’ve all heard that whole foods that are naturally high in fibre, protein, and vitamins are healthier relative to foods that are highly processed. However, there may be more to the story than meets the eye. In a study titled, “Which Foods May Be Addictive? The Roles of Processing, Fat Content, and Glycemic Load” published in the Public Library of Science peer-reviewed open access scientific journal (PLOS ONE), it was found that highly processed foods share pharmacokinetic properties (e.g. concentrated dose, rapid rate of absorption) with drugs of abuse. This is due to the addition of fat and/or refined carbohydrates and the rapid rate the refined carbohydrates are absorbed into the system, indicated by glycemic load. The study suggests that not all foods are equally implicated in addictive-like eating behavior, and processed foods, that are high in fat and glycemic load, which may share characteristics to drugs of abuse, are more frequently associated with “food addiction”.
“We are all hardwired to use food, as not only nourishment, but also for reward. The biological “reward” for high-sugar foods is so great that the mental and physical stress of giving them up is greater than our drive for health and weight management.”
– Dr. Cahill
“I think our research suggests that “food addiction” is real and is a significant contributing factor to obesity and diabetes. The research by our colleague Dr. Gearhardt, at Michigan State University, also suggests that highly processed, high-sugar foods are the most addictive types of food. I don’t believe you need to eliminate processed or high-sugar foods from your diet completely, but moderation and mindful eating is important” explains Dr. Cahill.
Dr. Cahill’s advice is to limit refined sugar and foods with a high glycemic load. “Our research, along with that of our colleagues, has shown that foods that are high in sugar may be the most addictive and it is these foods which are the hardest to give up”.
Listen to Dr. Cahill’s radio interview where he speaks about his research findings around the prevalence of food addiction in the general population.
Sources: 1 World_Health_Organization (2013) Obesity and Overweight. World HealthOrganization. ttp://www.who.int/mediacentre/factsheets/fs311/en/index. html. Accessed 2013 Agu 12. 2 Mokdad AH, Marks JS, Stroup DF, Gerberding JL (2004) Actual causes of death in the United States, 2000. JAMA: the journal of the American Medical Association 291: 1238–1245. 3 Swinburn BA, Sacks G, Hall KD, McPherson K, Finegood DT, et al. (2011) The global obesity pandemic: shaped by global drivers and local environments.The Lancet 378: 804–814. 4 Granados K, Stephens BR, Malin SK, Zderic TW, Hamilton MT, et al. (2012) Appetite regulation in response to sitting and energy imbalance. Applied Physiology, Nutrition, and Metabolism 37: 323–333. 5 Ziauddeen H, Farooqi IS, Fletcher PC (2012) Obesity and the brain: how convincing is the addiction model? Nature Reviews Neuroscience 13: 279–286. 6 Ifland J, Preuss H, Marcus M, Rourke K, Taylor W, et al. (2009)Refined food addiction: a classic substance use disorder. Medical Hypotheses 72: 518–526. 7 Barry D, Clarke M, Petry NM (2010) Obesity and its relationship to addictions: is overeating a form of addictive behavior? The American Journal on Addictions 18: 439–451. 8 Davis C, Carter JC (2009) Compulsive overeating as an addiction disorder. A review of theory and evidence. Appetite 53: 1–8. 9 Blumenthal DM, Gold MS (2010) Neurobiology of food addiction. Current Opinion in Clinical Nutrition & Metabolic Care 13: 359–365. 10 Fortuna JL (2012) The obesity epidemic and food addiction: Clinical similarities to drug dependence. Journal of Psychoactive Drugs 44: 56–63. 11 von Deneen KM, Liu Y (2012) Food Addiction, Obesity and Neuroimaging. In: Belin D, editors. Addictions – From Pathophysiology To Treatment: InTech. pp. 259–290. 12 Smith DG, Robbins TW (2012) The neurobiological underpinnings of obesity and binge eating: a rationale for adopting the food addiction model. Biological psychiatry 73: 804–810.
Dr. Farrell Cahill is a recognized leader in the field of obesity, diabetes, and exercise physiology in Canada. Through his expertise in genetics, endocrinology, and human physiology, Dr. Cahill explores the aetiology and management of both obesity and diabetes to improve occupational health and performance.