Our world is filled with constant cues for us to eat and drink: food advertising, vending machines and piles of confectionary at eye-level when trying to pay for daily essentials. Food cues trigger cravings, prompt eating, predict weight gain and are hard to resist. They can make you feel hungry even if you are not.
But we may not all be influenced by food cues in the same manner. Research suggests that obese individuals have increased activation of brain reward centres to visual food cues compared to healthy weight individuals.
Increasing evidence points to addictive-like behaviours when it comes to eating, which could explain our continuing issues when it comes to addressing obesity in Australia. Are we addressing the wrong issues when it comes to dealing with obesity? If it were as simple as calories in versus calories out Australia wouldn't have the obesity problem we're faced with.
Obesity is now a bigger issue than world hunger according to a study published in The Lancet looking at trends in BMI over time. The study showed that more people are now obese than underweight, indicating the extent of the global issue. There is a need to focus on how to help people eat better, with dietary intake recognised as the leading cause of disease burden, exceeding both smoking and high blood pressure. The Australian Health Survey demonstrates that, on average, 35 percent of adults and children's daily energy intake comes from 'discretionary' foods. These foods are often high in fat, sugar and salt.
New national data from the Australian Bureau of Statistics shows that one in two Australians (52 percent) exceed the World Health Organisation's (WHO) recommendation that free sugars contribute to less than 10 percent of total energy intake. The most likely group to exceed these sugar recommendations were children aged nine to 18 years. Current obesity prevention and weight-loss strategies are not sufficiently effective. There is a pressing need for new, more effective approaches to obesity prevention and treatment.
Food addiction offers a possible explanation for the excess weight gain of the obese and their weight-loss failures. Food addiction leads to people over-consuming specific types of food -- foods that are usually high in calories. Reviews suggest that around 20 percent of the population have a food addiction and indicate addictive-like behaviours to food, particularly highly processed or convenience foods. Food addiction is more likely in those who are overweight or obese and female.
However, food addiction can occur independent of weight status, suggesting that not all people who are overweight have a food addiction, but rather there's a subset of vulnerable individuals who may be affected by neurobiological differences. Once we uncover the cause, we can work on the treatment.
The term food addiction is a highly debatable topic among scientists and the public. The initial debate regarding whether food addiction exists has moved on to disagreement as to whether it is a substance or behavioural condition or a combination of both. Either way, food addiction is likely to be highly individual and driven by different foods for different people. As such, the term 'addiction to food' has been proposed as a better reflection of this condition.
Studies into public perceptions of food addiction show there is strong public support for seeing obesity as a form of addiction, with additional studies illustrating that food addiction is perceived to be more of a disease than smoking and to be caused by individual choices to a greater extent than alcoholism, reflective of the focus on personal responsibility surrounding both tobacco use and healthy eating/weight control. This suggests that food addiction is vulnerable to stigmatisation and may have substantial impact on wellbeing.
The consumption of foods high in sugar, salt and fat can induce addiction-like behaviours and characteristics including binge eating, tolerance, withdrawal, and craving. Relationships between these substances and food addiction are not well established in human studies as we eat whole foods and not sole nutrients. Currently, there is a lack of strong human evidence to support food addiction as a substance addiction or a behavioural condition despite the strongly held opinions of individual clinicians and researchers.
There is an increasing number of published scientific studies investigating food addiction in conjunction with other formally recognised mental health conditions such as depression, disordered eating and other symptomatic traits such as impulsivity. These studies suggest some overlap with these conditions and provide insights into the overlapping features of mental health conditions.
Notably, in the substance addiction field, negative emotional states such as anxiety and depression play a key role in increased addiction risk. There are many factors for a possible food addiction condition in humans which remain largely unexplored. If scientific evidence identifies that certain foods are capable of hijacking the brain in an addictive manner, it would be a landmark change that would support bold policy approaches and new treatment approaches.