Successfully Lose Weight

You need to establish the difference between appetite and hunger. Sometimes it is hard to know the difference. Hunger is that unpleasant feeling caused by the physical need for food whereas appetite is yuor desire for food, a pleasant sensation felt in the anticipation of eating. Recognising these two massive differences can make the difference between you controlling your eating or your eating controlling you.

Your urge to eat, whether you are truly hungry or not, is a complicated mix of your psychology, biology, and surroundings controlled by the hypothalamus on your brain. As simply as possible, your brain receives hunger signals from your gut and your bloodstream (which tell your brain to eat), satiety signals from your gut and fat cells (which tell your brain that you are full or need to stop eating) and 'emotional' messages from the cortex region of the brain, these can override true hunger messages so even if your body is telling you it is full your emotions will signal to the brain that it is time to eat! This whole process involves more than 20 different hormones and/or chemical messages.

The part of your brain that deals with fullness or satiety receives short term signals from the gut and long term signals from your fat cells. Within minutes of eating, stretch and chemical receptors in your stomach lining tell the brain that you have eaten something and then chemical receptors/messengers are released as you carry on eating. You can think of these chemical receptors like appetite suppressants that will tell the brain to stop eating when you have had enough. However, there is a small problem. It takes approximately 20 minutes after beginning a meal for this message to get through. So if you don't take your time then it is almost certain that you will have overeaten by the time the messages get through.

A study by Florida University found that people who rush at mealtimes ate 15% more calories. So, slow down, chew your food properly and enjoy it. If you can eat at a table and not in front of the telly because at least then you are focusing on eating and not eating absent mindedly whilst watching the telly! So if you slow down then you will be letting those brain chemicals work their magic!

A rise in blood sugar levels also signals your brain to stop eating. This triggers a release of insulin which in turn increases levels of the brain messenger serotonin. Serotonin makes you feel sated after a meal and switches off hunger signals.

The above are all short term signals, what about the long term signals? Your fat cells produce a chemical signal called leptin that acts as a fat thermostat to keep your body fat leevls at a constant and healthy level. If you gain weight, or more specifically, gain body fat then more leptin is produced. This signals to the brain to reduce your appetite and increase your calorie output by increasing your metabolic rate. If your fat levels dip too low, low leptin drive your appetite to increase and reduce your metabolic rate and signal your brain to eat.

Now, you may be reading this and thinking well if that is the case then why do we even have an obesity problem, read on..................

Unfortunately, in practise this leptin system doesn't always work perfectly (isn't that always the way in nutrition!). It is better at stopping people losing weight than gaining at and scientists believed that it evolved during an ag of food shortage. It would warn of low body weight and thus ensure that the body is fit to carry out essential functions such as growth and reproduction. When thinking of this in practical terms, if the body's fat stores dip too low then puberty will be delayed and fertility reduced. Unfortunately the same system does not seem to work as well with fat loss.

When your stomach is empty is produces ghrelin which is a hunger stimulating hormone. Ghrelin makes you want to eat more. As you get hungry, it's levels rise telling your hypothalamus that you need to eat. Similarly, as you eat, ghrelin levels fall telling your hyopthalamus that you are full and this in turn triggers feelings of satiety.

If you try to ignore these hunger pangs, ghrelin levels continue to rise sending even more signals to eat which eventuallly overrides your will power adn you eat for something quick and easy to eat which will more than likely not be the healthiest choice! This vicious chemical cycle only stops when you eat.. When your stomach is full very little ghrelin is produced which in turn reduces your appetite.

In a perfect system levels of ghrelin and leptin would balance each other. You would eat teh food that you needed and stop when you have had enough. In theory you should stay at the same weight. In reality the system does not work quite so well! Most people gain half a pound to a pound per year of their adult lives. This equates to an excess of 10 calories which is equivalent to half a teaspoon of sugar!

Despite all the biology I would say that the key to understanding your appetite is to be sensitive to your body's signals.