Your Brain and Appetite.

THE BRAIN AND FEEDING BEHAVIOUR

Our brain was designed for the Hunter Gatherer. Our primate ancestors were meant to seek food and conserve energy in between hunts to be able to survive an impending famine. The obesity pandemic today can arguably be attributed to an evolutionary mismatch in which our primate brain, designed to hunt and conserve fuel, is faced with a society that is laden with hyperpalatable foods at every corner we turn. The brain dictates our behaviour and weight retention to help us with a famine that will never come!

OUR APPETITE IS REGULATED BY TWO COMPETING AREAS IN THE BRAIN

The Hypothalamus is the region of the brain that likes balance. If you are energy depleted, it triggers signaling that makes you eat. If you are in an energy surplus, then it tells you to stop. It also happens to remember your HIGHEST weight – remember that the brain wants you to survive the famine, it does everything it can to remember the highest weight you’ve ever been and take you back to this weight any time you try to lose weight – this is the reason that everytime you’ve tried to lose weight, your weight has gone right back up (think yo-yo!).

The Mesolimbic Dopamine Centre is the reward centre of the brain. The reward centre is a dopamine rich pathway that mediates pleasure, motivation, cravings and seeking behaviour. Does that sound familiar? It’s original purpose was really for sexual intercourse and food (because hunter gatherers needed to produce offspring and survive the famine). Research shows that there are a plethora of agents that hijack this system to facilitate addictive behaviour; this includes narcotics (eg. morphine, heroine), amphetamines (eg. cocaine, ecstacy), alcohol, gambling and hyperpalatable and processed food. The more that a substance activates this area, the more efficient your brain gets at driving your motivation to get it. Your reward centre can also build a tolerance so that you need more of the substance to generate the same pleasure. Interestingly, food companies know about this system and engineer their food products to activate this area using intricate combinations of sugar, salt and fat. They experiment this in rodents and check to see that the food ingested generates activation of this area which they call the “bliss point”. This is exactly why you can never have just one chip!

Your weight is not a reflection of your willpower. It is a reflection of the interaction of your genetic makeup (which dictates your appetite regulation and metabolism), and the environment we live in. Most of the factors that influence our weight are beyond our control. Diet and exercise is a drop in the bucket.