DEFINITION
Type 2 diabetes is a condition that happens because of a problem in the way the body
regulates and uses sugar as a fuel. That sugar also is called glucose. This long-term
condition results in too much sugar circulating in the blood. Eventually, high blood sugar
levels can lead to disorders of the circulatory, nervous and immune systems.
In type 2 diabetes, there are primarily two problems. The pancreas does not produce
enough insulin — a hormone that regulates the movement of sugar into the cells. And
cells respond poorly to insulin and take in less sugar.
Type 2 diabetes used to be known as adult-onset diabetes, but both type 1 and type 2
diabetes can begin during childhood and adulthood. Type 2 is more common in older
adults. But the increase in the number of children with obesity has led to more cases of
type 2 diabetes in younger people.
There's no cure for type 2 diabetes. Losing weight, eating well and exercising can help
manage the disease. If diet and exercise aren't enough to control blood sugar, diabetes
medications or insulin therapy may be recommended.
SYMPTOMS
Symptoms of type 2 diabetes often develop slowly. In fact, you can be living with type 2
diabetes for years and not know it. When symptoms are present, they may include:
Increased thirst.
Frequent urination.
Increased hunger.
Unintended weight loss.
Fatigue.
Blurred vision.
Slow-healing sores.
Frequent infections.
Numbness or tingling in the hands or feet.
Areas of darkened skin, usually in the armpits and neck.
CAUSES/SOURCES
Causes
Type 2 diabetes is mainly the result of two problems:
Cells in muscle, fat and the liver become resistant to insulin As a result, the
cells don't take in enough sugar.
The pancreas can't make enough insulin to keep blood sugar levels within a
healthy range.
Exactly why this happens is not known. Being overweight and inactive are key
contributing factors.
How insulin works
Insulin is a hormone that comes from the pancreas — a gland located behind and below
the stomach. Insulin controls how the body uses sugar in the following ways:
Sugar in the bloodstream triggers the pancreas to release insulin.
Insulin circulates in the bloodstream, enabling sugar to enter the cells.
The amount of sugar in the bloodstream drops.
In response to this drop, the pancreas releases less insulin.
The role of glucose
Glucose — a sugar — is a main source of energy for the cells that make up muscles
and other tissues. The use and regulation of glucose includes the following:
Glucose comes from two major sources: food and the liver.
Glucose is absorbed into the bloodstream, where it enters cells with the help
of insulin.
The liver stores and makes glucose.
When glucose levels are low, the liver breaks down stored glycogen into
glucose to keep the body's glucose level within a healthy range.
In type 2 diabetes, this process doesn't work well. Instead of moving into the cells, sugar
builds up in the blood. As blood sugar levels rise, the pancreas releases more insulin.
Eventually the cells in the pancreas that make insulin become damaged and can't make
enough insulin to meet the body's needs.
SOURCES
Overweight, obesity, and physical inactivity
You are more likely to develop type 2 diabetes if you are not physically active and are
overweight or have obesity. Extra weight sometimes causes insulin resistance and is
common in people with type 2 diabetes. The location of body fat also makes a
difference.
Type 1 vs. Type 2 diabetes: What’s the difference?
Type 2 diabetes is not the same as Type 1 diabetes. In Type 1 diabetes, your pancreas
doesn’t make any insulin. In Type 2, your pancreas doesn’t make enough insulin, and
the insulin it is making doesn’t always work as it should. Both types are forms of
diabetes mellitus, meaning they lead to hyperglycemia (high blood sugar).
Who is at risk of developing Type 2 diabetes?
You’re more likely to develop Type 2 diabetes if you:
Are Black, Hispanic, American Indian, Asian American or Pacific Islander.
Are older than 45.
Have overweight/obesity.
Don’t exercise.
Had gestational diabetes while pregnant.
Have a family history of diabetes.
Have high blood pressure.
Have prediabetes (higher than normal blood sugar, though not high enough to be
Type 2 diabetes).
What are the complications of high blood sugar levels?
Potential complications of high blood sugar levels from Type 2 diabetes can include:
Digestive problems, including gastroparesis.
Eye problems, including diabetes-related retinopathy.
Foot problems, including leg and foot ulcers.
Gum disease and other mouth problems.
Hearing loss.
Heart disease.
Kidney disease.
Liver problems, including nonalcoholic fatty liver disease.
Peripheral neuropathy (nerve damage).
Sexual dysfunction.
Skin conditions.
Stroke.
Urinary tract infections and bladder infections.
Rarely, Type 2 diabetes leads to a condition called diabetes-related ketoacidosis (DKA).
DKA is a life-threatening condition that causes your blood to become acidic. People with
Type 1 diabetes are more likely to have DKA.
TYPES/CLASSES
Scientists in Sweden and Finland have found that Type 2 diabetes could be separated
out into four subtypes, which have distinct characteristics. This suggests that people
with Type 2 diabetes might be affected by their diabetes in different ways and benefit
from different treatments.
