What Is Pre Diabetes?

Pre diabetes is a condition in which blood sugar levels are higher than normal but without passing the threshold for diabetes. While pre diabetes may not always cause symptoms, it's a warning sign you shouldn't ignore.

According to the 2020 National Diabetes Statistics Report, around 1 in 3 Americans have the condition.

In this post, we'll take a closer look at this condition, its causes and risk factors, signs and symptoms, complications, and treatment.

What Is Pre Diabetes?

Pre diabetes is a buildup of glucose (or sugar) in your blood caused by a shortage of the hormone insulin or by cell resistance to this hormone.

The pancreas, an organ behind the stomach, secretes the hormone insulin to enable the cells in your body to use glucose as fuel. In prediabetics, insulin doesn't work as it should, failing to support the normal absorption of glucose in the cells.

To compensate for this, the pancreas works harder to produce insulin, but it fails to keep up with the demand. The result is a higher blood sugar concentration than normal that significantly increases the risk for type 2 diabetes.

According to the Centers for Disease Control and Prevention (CDC), over 84% of prediabetics don't know they have the condition. Pre diabetes is often discovered through blood tests and may or may not be accompanied by symptoms.

According to the CDC, you have pre diabetes if your blood tests show one of the following results:

  • Fasting Blood Sugar Test - 100 to 125 mg/dL (blood sugar levels after not eating overnight)
  • A1C Test - 5.7 to 6.4% (hemoglobin proteins coated with sugar)
  • Glucose Tolerance Test - 140 to 199 mg/dL (the amount of glucose in your bloodstream after fasting and then drinking at fixed intervals a sugary drink)

Unlike full-blown diabetes, pre diabetes may be reversed. This may even be possible without medication, through diet and lifestyle changes.

Causes and Risk Factors

People with pre diabetes cannot process glucose normally - the main type of sugar in the bloodstream and the main energy source of cells - and this accumulates in the blood. For some people, the cause is cell resistance to insulin. For others, the insufficient production of this hormone.

The exact mechanism behind the development of pre diabetes is not known. However, apart from genetics, several risk factors for pre diabetes are widely recognized:

  • Being overweight - Having a waist size over 35' for women and 40' for men increases the risk of cell resistance to insulin.
  • Unhealthy diet - A diet high in sugar, processed meat, and red meat.
  • Sedentary lifestyle - Being inactive and sitting a lot increases the risk of being overweight. It also doesn't use sugar for energy and reduces the body's ability to use insulin.
  • Being over 45 years old - Age increases the risk of developing pre diabetes. However, the condition can occur at any age.
  • Family history of type 2 diabetes - Having a sibling or parent with diabetes increases your risk.
  • Using tobacco - Smoking or chewing tobacco may increase your body's resistance to insulin.
  • Disrupted sleep - Studies correlate obstructive sleep apnea, a condition that disrupts sleep, with higher insulin resistance.
  • Polycystic ovary syndrome - Women with this condition have a higher risk of being diagnosed with pre diabetes.
  • Gestational diabetes - Having diabetes while pregnant is another risk factor, even if the blood sugar levels normalize after your pregnancy.
  • Certain medical conditions - High blood pressure or low levels of HDL cholesterol have also been associated with a higher risk of pre diabetes.
  • Race or ethnicity. Black, Hispanic, Asian, and American Indian people have a higher risk of developing the condition although it is unclear why.

These are the same risk factors that lead to the development of type 2 diabetes. Several of these factors are within your control.

Signs and Symptoms

Unlike type 2 diabetes, pre diabetes doesn't normally cause symptoms. Many prediabetics don't know they have the condition until routine blood tests pick up elevated blood sugar levels.

However, insulin resistance may trigger conditions such as polycystic ovarian syndrome in women or a skin condition such as acanthosis nigricans. Dark discoloration over the folds of the body and especially around the neck, armpits, elbows, knees, or knuckles may be a sign of pre diabetes.

Symptoms such as frequent urination, increased thirst, tiredness, or sores that won't heal can be a sign that pre diabetes has advanced to type 2 diabetes.


A study indicates that pre diabetes increases the risk of cardiovascular disease by 15% and that of all-cause mortality by 13%.

According to the same source, pre diabetes is especially dangerous for people with heart disease, increasing the risk of all cardiovascular disease and all-cause mortality by 37% and 36% percent respectively.

Left unchecked, pre diabetes can progress to type 2 diabetes. An article published in The Lancet notes that up to 70% of individuals with pre diabetes go on to develop type 2 diabetes, a condition which causes many complications including:

  • High blood pressure
  • Cardiovascular disease
  • Vision problems
  • Stroke
  • Nerve damage
  • Kidney damage
  • Alzheimer's disease

What makes the difference between those who develop pre diabetes and those who don't? Nutrition and lifestyle choices likely play a role.

Treatment and Prevention

The main treatment for pre diabetes tends to include dietary and lifestyle changes rather than medication.


Metformin may be prescribed to prediabetics considered at high risk of developing type 2 diabetes. However, while some studies support its efficacy, this medication is controversial.

Additional medication for managing high blood pressure and cholesterol may also be prescribed to limit the risk of cardiovascular disease.


Eating right is one of the best ways to manage pre diabetes and possibly check it before it can develop into type 2 diabetes. Diet, alongside other controllable factors, can also help prevent pre diabetes.

  • Watch out for the glycemic index of foods, or how fast a particular food raises your blood sugar level. Eat foods with a low GI index.
  • Avoid processed foods and refined carbs such as white bread, white rice, or russet potatoes.
  • Eat more fiber-rich foods including whole grains, fruits, and vegetables.
  • Avoid foods high in fat and calories.
  • Don't drink sugary drinks such as soda or juices - eat fruits instead or drink unsweetened tea.
  • Eat healthy protein sources such as beans, legumes, soybean, fish, and lean meat.
  • Drink plenty of water.
  • Drink alcohol in moderation or give it up altogether.
  • Stop smoking.

Other Ways to Treat and Prevent Prediabetes

In addition to dietary changes, a few other lifestyle changes are effective against pre diabetes.

  • Reduce your body weight if necessary. The CDC notes that a small amount of weight loss of 5% to 7% can lower your risk of developing type 2 diabetes if you carry some extra pounds.
  • Exercise for at least 150 minutes per week or 30 minutes a day. Coupled with a weight loss strategy, daily aerobic exercise can reduce the risk of pre diabetes progressing to type 2 diabetes by 58%. Walking instead of driving, riding a bike, taking the steps, and going to the gym can all make a difference.
  • Manage stress through meditation and other strategies. Stress associated with pre diabetes may make it difficult for you to follow your dietary and exercise goals.


Prediabetes increases your blood sugar levels and puts you at risk of type 2 diabetes while increasing your mortality risk.

It often doesn't have any obvious signs and symptoms, but it can be diagnosed through standard blood sugar tests.

You can manage pre diabetes and even reverse it through healthy dietary choices, physical exercise, and changes to your lifestyle.

Small everyday changes can have a powerful cumulative effect and make the condition much easier to manage. Start today.