Managing optimal weight is a component of maintaining a healthy lifestyle. This is because being obese and overweight are risk factors for several serious illnesses such as cancer, diabetes, high cholesterol, heart attacks, high blood pressure, brain strokes among others.
Overweight and obese people, therefore, need to lose weight to minimise the risk of acquiring these lifestyle diseases. Weight loss involves a healthy diet regimen coupled with regular exercises. And the brain plays an essential role in helping people to stick to these activities. This is because there are components by which the brain regulates diet control and eating.
Role Of The Hypothalamus
The hypothalamus is an endocrine gland positioned in the brain. It is deeply involved in regulating eating behaviour. It has ‘satiety’ and ‘hunger’ centres, which make us eat food when hungry and stop, when full. These deal with a variety of chemicals/hormones.
It is also known as the ‘hormone of energy expenditure’. It is abundantly made by adipose (fat) cells. It monitors energy balance by prohibiting hunger. Less hunger leads to less food consumption, which eventually means weight loss. Leptin expands its effects by acting on the hypothalamus (arcuate nucleus). Obese people have ‘leptin resistance,’ which means that hunger is not inhibited, despite the presence of higher levels of leptin, resulting in overeating. This is equal to ‘insulin resistance’ in diabetic patients.
This one is also known as the ‘hunger hormone.’ Ghrelin acts on the hypothalamus to trigger hunger. Hence, the effect of ghrelin is quite the opposite of that of leptin. After eating, ghrelin levels decline to the lower levels. It rises again before the time of the next meal, to stimulate hunger.
So it is always the balance between the levels of leptin and ghrelin that monitor eating behaviour. Cholecystokinin and glucagon-like peptide-1 are released when the food enters the small bowel. So these hormones make us feel full, and we eventually stop eating.
Pleasure Centres In The Brain And Eating Behaviour
Food is vital for survival; it is a pleasure linked with food that makes eating worthwhile. When we are happy, we eat more! The reverse is also true. When an individual has eaten to his/her heart’s desire, there is happiness and satisfaction. Almost in every celebration or party, it involves a good spread of various food items.
Happiness combined with eating food; as a result, food accelerated the same reward system of the brain that gets accelerated by other pleasurable activities such as games or watching a movie. The area tangled in a ‘reward feeling’ is the mesolimbic cortex of the brain and the effects are resolved by a neurotransmitter, dopamine.
All types of food stimulate reward centres of the brain. However, the effects are more initiated with sweet items or high-calorie foods such as cakes, chocolates, sweets, aerated soft drinks, etc. This explains why some people crave for more sweets/cakes. The pleasurable sensation associated with eating desserts can force an individual to have them, despite being full.
The hypothalamus has ‘hunger’ and ‘satiety’ centres which make us eat food when hungry and makes us stop when full
Over a period of time, eating can become an ‘addiction’ too, similar to smoking or alcohol addiction. A ‘food-addicted’ person eats purely to experience the pleasurable sensations associated with eating, rather than to satisfy hunger. This behaviour can result in obesity and overweight. Psychiatry and counselling consultation may help in these situations.
Role Of Special Senses In Eating Behaviour
- When it comes to the exclusive and liking of food, plethora of factors play a role. These include the smell, look and taste of food.
- An aroma of food can be experienced from a distance, which increases the appetite and desire to eat.
- The taste of good food is vital, as it increases appetite.
- A dish nicely arranged and well served is very appealing.
Thus the sensations – sight, smell and taste of food are recognised and appreciated in specific brain centres. Hence, damages or disorders of neurons in these particular brain areas can affect eating behaviour of an individual.