blood glucose levels and obesity

• Glucose is needed by cells for respiration. The concentration of glucose in the blood must be maintained at a constant level and controlled carefully.
• Chronic elevated blood glucose levels can lead the epithelial cells lining blood vessels to absorb far more glucose than normal. This can cause atherosclerosis and blood vessel damage.
• Insulin is a hormone produced by the pancreas. It regulates glucose concentrations in the blood.

  • Pancreatic receptors respond to raised blood glucose levels by increasing the secretion of insulin from the pancreas.
  • Insulin activates the conversion of glucose to glycogen in the liver decreasing blood glucose concentration.
• Glucagon:

  • Pancreatic receptors respond to lowered blood glucose levels by increasing the secretion of glucagon from the pancreas.
  • Glucagon activates the conversion of glycogen to glucose in the liver increasing blood glucose concentration.
• During exercise and the fight or flight response, glucose concentrations in the blood are raised by adrenaline released from the adrenal glands. This stimulates glucagon secretion and inhibits insulin secretion.
• Type 1 Diabetes:

  • A person with type 1 diabetes is unable to produce insulin and can be treated with regular doses of insulin.
  • The onset of Type 1 diabetes usually occurs in childhood.
• Type 2 Diabetes:

  • In Type 2 diabetes, individuals produce insulin, but their cells are less sensitive to it. This insulin resistance is linked to a decrease in the number of insulin receptors in the liver, leading to a failure to convert glucose into glycogen.
  • Type 2 diabetes typically develops later in life. The likelihood of developing type 2 diabetes is increased by being overweight.
• Urine Test:

  • In both types of diabetes, individual blood glucose levels rise rapidly after a meal. The kidneys remove some of this glucose, resulting in glucose appearing in urine.
  • Testing urine is often used as an indicator of diabetes.
• Glucose Tolerance Test

  • The blood glucose concentrations of the individual are initially measured after fasting. The individual then drinks a glucose solution and changes in their blood glucose concentration are measured for at least the next two hours.
  • The blood glucose concentration of a diabetic usually starts at a higher level than that of a non-diabetic.
  • During the test, a diabetic’s blood glucose concentration increases to a much higher level than that of a non-diabetic and takes longer to return to its starting concentration.
• Small blood vessels damaged by elevated glucose levels may result in haemorrhage of blood vessels in the retina, renal failure or peripheral nerve dysfunction.