Key area eight – blood glucose levels and obesity

What happens if blood glucose levels are chronically elevated?

• if Levels of blood glucose become elevated the endothelium Sales lining the blood vessels absorb more glucose than normal, damaging the blood vessels

• Atherosclerosis May develop leading to cardiovascular disease,/or peripheral vascular disease

• The walls of small blood vessels thicken, they lose strength and burst and bleed, resulting in hemorrhage of blood vessels in the retina of the eye retinal failure, or peripheral nerve dysfunction

Insulin

Insulin is a hormone produced by the pancreas. It regulates glucose concentrations in the blood.

Negative feedback control of glucose levels

If the blood glucose concentration is too high, the pancreas produces insulin. This causes glucose to move from the blood into the cells, where the excess glucose is stored:

• some is stored as body fat

• liver and muscle cells convert excess glucose to glycogen for storage and use at a later date

Hormonal negative control of glucose

• The pancreas controls blood glucose with two hormones, insulin and glucagon which act Antagonistically

Roles of hormones in negative feedback control of blood glucose levels

• incident activates the conversion of glucose to glycogen in the liver, decreasing blood glucose concentration

• Pancreatic receptor response to the lower blood glucose level by increasing secretion of glucagon from pancreas

• They travel to the liver in the blood

• The high concentration of insulin makes the liver cells more permeable to glucose so they absorb more

• In the liver cells, glucose molecules are joined together To form glycogen

• Is glucose removed the blood glucose concentration decreases to normal

• The higher glucagon concentration causes glycogen to be converted into glucose in the liver increasing blood glucose levels

What is adrenaline?

• Adrenaline (also known as epinephrine) is a hormone produced in the adrenal gland. It is released when the body is under acute stress or during exercise. It increases blood flow to the skeletal muscles and the level of glucose in the blood.

• Once the emergency is over, insulin brings the blood glue for concentration back to normal

How is glucose regulated

What is diabetes?

Diabetes is a condition where the blood glucose levels remain too high. It can be treated by injecting insulin. The extra insulin causes the liver to convert glucose into glycogen, which reduces the blood glucose level.

Type one diabetes

• usually occurs in childhood

• Unable to produce insulin

• Treated with regular injections of insulin

type two diabetes

• typically developed later in life

• Likelihood of developing type two diabetes is increased by being overweight

• Individuals produce insulin, but their cells are less sensitive to it

• This insulin resistance is linked to decrease in the number of insulin receptors in the liver leading to a failure to convert glucose into glycogen

Similarities and testing between both

• individual blood glucose levels will rise rapidly after a meal. The kidneys will remove some of the glucose resulting in glucose appearing in urine.

• Testing urine for glucose is often used as an indicator of diabetes

• The glucose Tolerance test is used to diagnose diabetes

• The blood glucose concentration of the individuals 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 reverse concentration of a diabetic usually starts at a higher level than that of a non-diabetic

Obesity

• obesity is a major risk for cardiovascular disease and type two diabetes

• Obesity is characterized by excess body fat in relation to lead body tissue

• Obesity may impair health

• Obesity is linked to high fat diet and a decrease in physical activity

• The energy intake in the diet should limit fat and free sugars as fats have high caloric value per gram and free sugar is required no metabolic energy to be expended in their digestion

• Exercise increases energy, expenditure, and preserves lean tissue

• Exercise can help reduce the risk of CBD by keeping weight under control, minimizing stress, reducing hypertension, and improving HDL blood leopard profiles

BMI

• A body mass index is weight times height and a BMI higher than 30 is used to indicate obesity

• The disadvantage of calculating BMI is that someone may be wrongly classified as overweight or obese when additional weight is not fat, but muscle or bone mass