To maintain this balance in our blood sugar the body works in a similar way to the thermostat on a central heating system. Our natural 'thermostat' clicks into action as glucose levels rise and fall.
In this homeostatic system, the following components are present:
- Pancreas: acts as the Monitor
- Islets of Langerhans : acts as the Control Center
- Liver, muscles & other body cells : act as Regulators
The body takes action in the following ways:
When the glucose levels fall too low
The hormone adrenaline is released from the adrenal glands and glucagon is produced from the pancreas. Glucagon works in the opposite way to insulin and increases blood glucose by encouraging the liver to turn some of its glycogen stores into glucose to give us quick energy. If the blood glucose level stays low for a period of time hypoglycaemia – low blood sugar level – can occur.
Symptoms include: irritability, aggressive outbursts, palpitations, forgetfulness, lack of sex drive, crying spells, dizziness, anxiety, confusion, forgetfulness, inability to concentrate, fatigue, insomnia, headaches, muscle cramps, excess sweating and excessive thirst.
Sounds familiar? Chances are that if you have a history of dieting then some or many of those symptoms are known to you. In themselves they can be burdensome, but more importantly they are the outward manifestations that your body is having trouble maintaining a good blood sugar level. They can certainly undermine the efforts of many dieters by triggering unhealthy eating which contributes to weight gain.
The pancreas detects an abnormally low blood glucose level and relays this information to the Islets of Langerhans. In response, the Islets of Langerhans increase their secretion of the hormone glucagon.
a). Glucagon promotes the conversion of glycogen to glucose in the liver, a process known as Glycogenolysis. In this process, the stored glycogen is converted to glucose phosphate, which then, through a series of reactions can be converted to free flowing glucose as needed.
b). Glucagon also promotes the conversion of fat stored in other (fat and muscle) cells of the body to glycerol and fatty acids, which can be further converted to glucose as needed.
Hence, blood glucose levels are restored.
When the glucose level rises too high
Insulin is produced by the pancreas to lower it. If the blood sugar level remains too high, this causes the symptoms of hyperglycaemia – high blood sugar level. The extreme form of this is diabetes which is a medical condition needing expert attention often entailing regular insulin injections. Weight cycling – weight gain, loss then gain – may make you more prone to diabetes. Obese people have a 77 times higher chance of developing diabetes than a person at their correct weight – the greater your weight the higher the risk of developing diabetes.
The pancreas, acting as the monitor, detects an abnormally high level of blood glucose and sends this information to the Islets of Langerhans in the pancreas (acting as the control center). The Islets of Langerhans in turn increase their secretion of the hormone Insulin.
a). Insulin increases the amount of glucose absorbed by muscles and other (fat) cells of the body, facilitating it's conversion and storage as glycogen, a process called glycogenesis.
b). Also, insulin aids the liver in the conversion of glucose to glycogen, which is then stored in the liver.
c). Now, if the blood glucose levels remain elevated, the Islets of Langerhans secrete a third hormone called Somatostatin. The function of this hormone is to inhibit the activity of glucagon (which promotes conversion of glycogen to glucose), thus preventing any unnecessary extra glucose being dumped into the blood stream.
Hence, the elevated blood glucose levels are lowered to the normal levels.
references:
3. http://www.positivehealth.com/article/diabetes/how-to-maintain-glucose-levels
No comments:
Post a Comment