Obesity, eating disorders and food addictions

This blog provides free general information for anyone who is seeking to understand more about eating disorders and food addictions, not intended as a medical consult. Please seek appropriate medical and allied health advice for individual assessment and management.


  • Overeating is consumption of a large amount of food without a loss of control.
  • Binge eating is the comsumption of a large volume of food or increased frequency of eating with loss of self-control.
  • Grazing is eating or nibbling continuously over an extended period of time associated with a loss of control.
  • Emotional eating is eating in response to anxiety, boredom, positive or negative emotions.
  • Night eating syndrome is a form of atypical eating pattern, where there is lack of appetite during the day time and excessive eating in the evening, where >50% of the energy intake is consumed after 7pm.
  • Eating disorder also includes excessive intake of high calorie beverages (not just solid foods) of >2 litres a day.

Disordered eating behaviour

Pre-operative eating disorders (especially binge or uncontrolled eating) are likely to be retained after bariatric surgery, which often leads to inadequate weight loss or weight regain in the medium term.

In a physical sense the large volume of food consumed may contribute to pouch dilatation (after a gastric band, sleeve gastrectomy or gastric bypass), loss of restriction/satiety. This may lead to greater psycho-social stress and a personal sense of disappointment or failure.

Disordered eating behavior impairs the individual capacity to comply with post surgical treatment recommendations. This may not be evident immediately to the medical team and the physical signs may be non-specific complaints from the patient, such as food intolerance and dumping, early abdominal discomfort with food (also from rapid eating, inadequate chewing or drinking too much with foods) or vomiting (from binge eating).

Hence it is important to start screening for eating disorders before bariatric surgery and attempt to understand what types of common eating disorder that do exist. Best results are achieved when these disorders are addressed concurrently.

Maladaptive eating behaviour

Post op maladaptive eating behavior is failure to adapt after bariatric surgery.

  • This may be the result of having large meal portions, fail to chew food thoroughly or eat slowly or non-compliance to post op diet instructions, typically a return to food with high fat/sugar content.
  • The physical symptoms include regurgitation, reflux, vomiting, abdominal pain, nausea, bloating or dumping (dizzy, fainting, need to lie down after meals, diarrhea).
  • Hence the patient will then engage in compensatory behavior to alleviate these symptoms rather than avoiding the offending food choices or change their eating habits.


Cognitive ability to adapt after bariatric surgery

In order to achieve successful weight loss (durability) and patient satisfaction, there must be an ability to adapt to the surgery. Adherence to post op dietary guidelines (compliance) is vital in order to achieve the necessary excess weight loss and prevent macro or micronutrient deficiencies.

Cognitive function after bariatric surgery is linked to the extent of post op weight loss. It is important that patients understood, registered and remember the pre and post op instructions.

Cognition starts with pre-operative consultation and patient education. The patient is assessed as to their level of understanding of the surgery (physically and mentally be prepared for bariatric surgery) and needs to be able to cope after surgery with the radical lifestyle changes.

Patients need to be able to:

  • Understand the consequences of bariatric surgery and their new relationship with food.
  • Plan ahead for healthy meals.
  • Resist tempting foods.
  • Select the optimal food choices when presented with a range of food options.
  • Incorporate exercise into a daily routine.

The task is made easier if patients do have a supportive family and wide social network, often made easier if there are family members, relatives or friends who already had a similar weight loss procedure. This social support is not to be underestimated. Nowadays with the social media and modern technology, geographical isolation (those who live in remote towns) is no longer a barrier for bariatric surgery.

Surgery are not recommended for patients who does not wish to have a lifestyle change or those who are not physically or mentally prepared to undergo surgery.

Food addictions

Morbid obesity is often the result of a complex interaction between genetics, ageing (changes to body physiology), central neural, medication side effects (for example antiepileptics, antidepressants, steroids and diabetic medications), environmental and lifestyle factors (Western society diet intake and sedentary behavior). The cumulative results of ingesting more energy than is expended over a long period of time and storing the excess energy as body fat is the physical evidence of this process.

There may also be an element of food addiction that is responsible for excessive food intake and increased adiposity in a subset of obese people. At the present time food addictions unlike substance abuse is not recognized as a psychiatric or mental disorder but is definitely a risk factor to developing obesity. Conversely failure to address food addictions or eating behaviour is definitely contributing to inadequate weight loss and weight regain (recidivism) after successful surgery. Obviously soft drinks and alcohol is included in this food addiction category, often drank in conjuction with high calorie nibbles (cheese, nuts, chips, etc.).

It is suspected that access to sugar or highly palatable diets in our Western society may provoke behavioral signs of addiction, including withdrawal and cross-sensitization as well as neurochemical adaptations in the central brain. Similarly artificial sweeteners may cause desensitization of the sweet taste buds and cause craving for sweet foods.

Some patients exhibit behavioral characteristics associated with typical substance addiction, such as greater impulsivity and emotional reactivity, crave food more frequently, are more likely to engage in binge eating and emotional eating. Some studies have food that food addictions and unhealthy binge eating is found in about one third of patients undergoing surgery.

Bariatric surgery has been found to reduce food addictions in over 90% of patients. The mechanisms are unclear although the dopamine receptor pathway in the central brain may play a role.

A new restrained eating behavior adopted after surgery reflects a cognitive strategy to help patients counteract their heightened sensitivity to the rewarding value of food (sweet, savoury and fried/BBQ foods high in saturated animal fats or trans fat).

It is important to recognize that food addictions and eating disorders may lead to unsatisfactory weight loss, sabotage or weight regain (weight recidivism) despite early success after bariatric surgery. Hence it is important when this issue is detected, appropriate counseling by experts (dietician, psychologist, medical practitioner, physician or surgeon) are prescribed as well.