The idea of food addiction is an area of medical research that is gaining ground recently in the study of obesity.
Indeed, it is a very interesting concept. The premise of food addiction does not tend to include all food groups.
Let’s face it not many of us spend a lot of time thinking about all the salad and vegetables that we binged on the day before.
- refined sugars
- refined carbohydrates
The Scientific Theory Behind Food Addiction
(i) Sugar Addiction
Indeed, there have been a few well-cited studies on animals and addictive behaviour. The studies show that given a choice between cocaine and sugar, rats and mice will choose sugar, even when they are already cocaine-addicted.
However, similar studies have also been applied to humans. One scientific study 5, discussing the ‘sweet’ receptors in our brains concludes that:-
“The supranormal stimulation of these receptors by sugar-rich diets, such as those now widely available in modern societies, would generate a supranormal reward signal in the brain, with the potential to override self-control mechanisms and thus to lead to addiction“
ii) Carbohydrate Addiction
It is not all carbohydrates that are a problem for food addiction.
Carbohydrates that the body absorbs and digests very quickly cause a rapid rise in both blood glucose and insulin levels. These carbohydrates are known as high-glycemic-index carbohydrates.
So, the following carbohydrates are examples of foods with a high glycemic index:-
- white bread
- white pasta
- breakfast cereals, such as cornflakes
- french fries
So, next time you have a carb craving after a heavy night on the town or an argument, think on. You may be struggling with food addiction.
However, it is important to note that these types of carbs only trigger addiction-like behaviors in a subset of ‘vulnerable’ individuals.
Nonetheless, the above study argues that changing the treatment approach for some obese people may be effective in the fight against obesity.
iii) Salt Addiction
Although, again, the idea of salt addiction is controversial in the medical world, there are many research studies that suggest an addictive element for some inidividuals.
There is no doubt that an excess of sodium in the diet plays a role in the development of obesity and high blood pressure (hypertension).
Furthermore, an excess of salt in the diet can have negative effects on the heart, blood vessels, kidneys and brain. 10
However, it is important to remember that salt is essential to health. But we are not talking about a small sprinkling of salt added to your dinner.
Indeed, most of our sodium intake (around 71% 11) arises from hidden salt in foods, especially processed foods. Prime culprits of high sodium foods include bread and cakes, processed cheese and meats, soups, pizzas, sauces and gravy.
A 2016 review 12 on salt addiction shows that salt intake activates the lateral hypothalamus (LHT) in the brain that, in turn, releases dopamine. Dopamine then stimulates the nucleus accumbens (NA) and other limbic systems, central to reward pathways and addiction.
Although, there is a way to go in the research related to salt addiction, there are a number of medical studies that agree excessive salt intake is an addiction.
(iv) Fat Addiction
As with our previous three food groups, some foods rich in fats are also what are known as highly-palatable foods.
One research study 14 argues that, because people don’t binge on broccoli, there is some aspect in certain foods that are rich in fat and/or sugar that encourage binge eating.
Medical studies 15 also suggest that laboratory animals will binge on fats. Furthermore, if the fat is restricted to only three times a week the binge eating increases.
Similar to our other tricky customers above, it is not all fats that are a problem. So, it is saturated fats or trans fats, again found in processed foods, that have addictive qualities similar to that of Class A drugs.
A 2016 medical study 16 on rats shows that again, saturated fat intake (palm oil) acts on the brain’s reward signalling in a similar way to that of other drugs of a