What Causes Type 2 Diabetes?

What Causes Type 2 Diabetes?

Your body requires glucose to produce energy for daily functions. Type 2 diabetes affects the way your body uses glucose.

With type 2 diabetes, the amount of insulin is insufficient to allow entry of glucose into cells, or the response is not enough to sustain normal glucose metabolism and the extra glucose accumulates in vessels.


The reason why some people develop type 2 diabetes while others don’t is still a mystery. However, the disease progresses predictably – initial insulin resistance or the pancreas does not pump enough insulin into the blood.

How insulin works

Insulin is produced by beta cells of your pancreas, just behind and below the stomach.

Sometimes doctors refer to insulin as a hypoglycemic hormone. What this means is that after insulin is released into circulation, it causes glucose to enter into cells for metabolism and reduces your blood sugar level. When blood sugar is low, the pancreas stops releasing insulin.

The role of glucose

Sugar, or glucose, is the basic element used in making energy.

  • Its main sources are food and stored fat (glycogen) in the liver.
  • It is transported into cells under the influence of insulin.
  • Your liver not only stores but synthesizes glucose
  • When you don’t eat and your sugar levels drop, the liver breaks down glycogen, converting it to glucose.

Type 2 diabetes is a result of high blood sugar because of faulty glucose metabolism. When insulin is not produced in the right amount, glucose will not move into cells of your muscles and brain increasing blood sugar. The pancreas can increase insulin production but after some time this also fails.

Risk factors

Known risk factors for type 2 diabetes are:

  • Weight. The risk of type 2 diabetes is higher in overweight people. Nonetheless, not all cases progress to type 2 diabetes.
  • Fat distribution. Men with a waist circumference of more than 40 inches (101.6 centimetres) and women measuring above 35 inches (88.9 centimetres) are susceptible to type 2 diabetes. Accumulating more fat on around your waist is a predisposing factor in type 2 diabetes than if fat is concentrated around hips and thighs.
  • Inactivity. Inactivity increases the conversion of glucose into body fat instead of being used for energy production. This increases your chance of getting type 2 diabetes.
  • Family history. Your risk of type 2 diabetes is higher if siblings, parents, or close relatives suffered from the same disease.
  • Race or ethnicity. While no one knows why, the prevalence of type 2 diabetes is higher among Blacks, Hispanics, American Indians, and Asian Americans.
  • Age. Type 2 diabetes is normally a disease of adults and the elderly. This implies that your risk of getting type 2 diabetes increases with age, especially after 45 years. However, current statistics show new cases in children and younger adults.
  • Prediabetes. Blood sugar can be above the normal limits but is not high enough to be classified as diabetes. The prediabetic stage is asymptomatic and can progress to type 2 diabetes if untreated.
  • Gestational diabetes. Elevated blood sugar in pregnancy is known as gestational diabetes. If your sugars were high during pregnancy, or your child weighed more than 9 pounds (4 kilograms), you are predisposed to type 2 diabetes.
  • Polycystic ovarian syndrome. This relatively common syndrome in women – often results in excessive body hair, obesity, and irregular menstrual periods – increases the risk of type 2 diabetes.
  • Areas of darkened skin, usually in the armpits and neck. Acanthosis nigricans, changes on your skin in type 2 diabetes, is a sign of insulin resistance.


In its early stages, type 2 diabetes doesn’t raise many red flags and you could be asymptomatic. However, in the long run, you could end up with heart and cardiovascular problems, kidney diseases, and eye problems.

Most complications develop slowly and checking your blood sugar will tell if you are at risk. Possible complications in type 2 diabetes include:

  • Heart and blood vessel disease. Type 2 diabetes can lead to high plod pressure, stroke, heart disease and vessel plugging with fat plaques (atherosclerosis).
  • Nerve damage (neuropathy). Excess sugar is deposited on nerve fibers damaging them. Signs of neuropathy normally starts on feet spreading upwards. If blood sugar is not controlled, you can lose sensation in affected limbs.

When nerves of the digestive system are involved it results in vomiting, nausea, diarrhoea, and constipation.

Other symptoms in men include erectile dysfunction.

  • Kidney damage. Glucose accumulation in kidneys reduces interferes with the elimination of waste, or lead to kidney failure.
  • Eye damage. Complications affecting the eye include glaucoma, cataracts, diabetic retinopathy (damaged blood vessels of the retina), and blindness.
  • Slow healing. An impaired immune system cannot fight bacterial infections. Sores, blisters, and wounds take long to heal and may require foot or leg amputation.
  • Hearing impairment. Type 2 diabetes increases the risk of hearing deficits.
  • Skin conditions. Recurrent bacterial and fungal skin infections affect people with type 2 diabetes more.
  • Sleep apnea. Obstructive Sleep Apnea (OSA) is common in type 2 diabetes. OSA is probably caused by obesity. Weight loss and managing blood glucose may help but there is no scientific evidence to back this.
  • Alzheimer’s disease. High blood glucose over time increases the risk of Alzheimer’s disease although the exact cause is unknown.


Diabetes is a chronic disease which you have to manage most of your life. Changing lifestyle habits can slow or stop the progression of complications.

A lifestyle overhaul includes:

  • Eating healthy foods. Increase your daily portion of vegetables, fruits, grains, low fat, and fibre-rich foods.
  • Getting active. Have some you time – about 30 to 60 minutes of aerobic activity – at least four or five days a week. Go for walks, swim, cycling, or jogging around your neighbourhood.
  • Losing weight. Weight loss has been proven to prevent the risk of diabetes. Shredding 5 to 10 percent of your body weight should be your target. Weight loss not only reduces weight but also takes some stress off your heart.
  • Avoiding being sedentary for long periods. Limit your screen time, don’t be a couch potato. Every 30 minutes, walk around for a few minutes.

If your doctor recommends it, there are some drugs that you will be prescribed to control blood sugar. Even while using the medicine, continue exercising and eating good food to manage diabetes.