Early Warning Signs of Prediabetes, Risk Factors, and How To Reverse It

Key takeaways

• Prediabetes is a precursor to type 2 diabetes mellitus and is mostly characterized by hyperglycemia (high level of sugar in the blood), slightly less than type 2 diabetes mellitus. 
• Prediabetes is mainly without symptoms, but in some cases, some of its early warning symptoms may include polyphagia (excessive eating), unexplained weight loss, high BMI, weakness, sweating, blurred vision, and recurrent skin infections. 
• Prediabetes can cause long-term complications, such as hypertension, cancer, depression, diabetic neuropathy, and diabetic kidney diseases. 
• Major risk factors for prediabetes include age, ethnicity, family history, hypertension, gestational diabetes (diabetes during pregnancy), polycystic ovarian syndrome, dyslipidemia, and tobacco and alcohol abuse. 

Prediabetes is a health condition in which the blood glucose level is higher than normal but isn't high enough to be diagnosed as diabetes mellitus. Hence the name "prediabetes".

Other names for prediabetes include:

• Non-diabetic hyperglycemia
• Impaired fasting glucose (IFG)
• Impaired glucose tolerance (IGT)
• Impaired glucose regulation (IGR)

According to the World Health Organisation (WHO), the normal range for fasting blood glucose is between 70 mg/dl (3.9 mmol/l) and 100 mg/dl (5.6 mmol/L). Of course, this range will vary slightly in healthy individuals during and shortly after meals, which will then spike their glucose levels temporarily. 

However, for prediabetic patients, their hyperglycemic levels (high blood glucose level) are continuously elevated. This hyperglycemia can range from 110 mg/dl to 125 mg/dl.

Many people who have prediabetes are unaware that they have it. However, studies have shown that people diagnosed with prediabetes run a high risk of developing type 2 diabetes mellitus (full-blown diabetes) if left untreated.

Research shows that over 100 million Americans may currently have both prediabetes as well as type 2 diabetes. Meanwhile, In the U.K., there are 3.2 million people with diabetes as well as an estimated 1.2 million type 2 diabetes patients. 

Globally, it is estimated that by 2045, the number of adults with prediabetes could rise to 548 million, equating to 8.4% of the world’s adult population. 

Possible early signs of prediabetes

Although most people with prediabetes do not have any immediate symptoms, some possible early warning signs of prediabetes could help in diagnosing the condition.

1) Elevated appetite (polyphagia)

The digestive tract converts food into glucose after each meal. The presence of absorbable glucose in the bloodstream decreases your appetite. People with prediabetes have high amounts of free glucose in their bloodstream. 

These glucose molecules remain free and unbound to cells due to low amounts of insulin and/or insulin resistance to tissues. Insulin is a hormone produced by the pancreas that lowers blood glucose levels by enabling the body's cells to recognize, utilize, and store free blood glucose. 

Put simply, people who have prediabetes cannot utilize the free glucose in the bloodstream. The absence of sugar in the cells increases their appetites, resulting in excessive eating.

2) Unexplained weight loss

A recent 2021 study showed that new patients who were recently diagnosed with prediabetes could, over time, be prone to losing a small percentage of their body mass index (BMI).

Although there isn't much information as to how this occurs, it is suspected that the patient's tissue cells may be starved of the energy they require to function, which over time may result in cell death and then unexplained weight loss. 

Unexplained weight loss may be considered a symptom of prediabetes, especially with patients who have a family history of unexplained weight loss identified as a symptom in their family members or relatives who were diagnosed with prediabetes and/or Type 2 diabetes mellitus. 

3) High body mass index

A research journal published in 2023 reported on a research study conducted on Chinese patients in about 32 regions in the country. 

Results from the research study suggest that an increase in body mass index (BMI) seen in overweight (BMI:24-28kg/m2) and obese people (BMI ≥ 28kg/m2) is positively associated with the risk of developing prediabetes.

These individuals were also predisposed to having an increased progression from prediabetes to being type 2 diabetics, as well as having a slow regression from prediabetes to normoglycemia (normal glucose level).

So far, there are limited research studies on the relationship between BMI and regression to normoglycemia (normal glucose levels) from prediabetes. 

4) Weakness/fatigue

Fatigue is considered a common symptom in those who have diabetes or prediabetes. A recent study carried out in 2022 on people with these conditions suggests that 88.2% of those with prediabetes may experience fatigue.

The numbers were slightly higher in those with diabetes, as 89% of them reported experiencing fatigue. Individuals with a family history of prediabetes or diabetes who experienced fatigue due to their ailment are likely to experience this symptom as well, seeing as it may be genetic.

5) Blurred vision

Blurred vision is associated with prolonged elevation of blood sugar levels. It is the primary symptom of prediabetes and insulin-resistant diabetes mellitus (type 2 diabetes).

Chronic hyperglycemia has been known to affect the eyes and other major organs of the body. In diabetic patients, chronic hyperglycemia can result in diabetic retinopathy, which causes vision-threatening damage to the retina that can result in permanent loss of vision.

6) Slow-healing cuts or bruises

Although slow healing of cuts and bruises is mostly common in diabetes, chances are that those with prediabetes may also experience this symptom. There is little scientific information to back the claim that links prediabetes to the slow healing of cuts and bruises. 

However, both type 2 diabetes mellitus and prediabetes share similar causative factors, which are hyperglycemia and impaired glucose metabolism. 

A 2022 study carried out on rats with induced type 2 diabetes proved the effect of hyperglycemia on the endothelium (cell lining) of blood vessels and various tissues. Hyperglycemia causes nerve damage and restriction in blood flow, oxygen, and nutrient supply by impaired arteriole, resulting in delayed wound healing.

The inability of these wounds and cuts to heal properly may result in complications like the development of diabetic ulcers due to increased nerve and tissue damage in the affected area.

7) Recurrent skin conditions

Skin infections are a common sign of type 2 diabetes but may also be seen in prediabetes. These skin infections arise due to the immunosuppressive effects of hyperglycemia in prediabetic and diabetic patients. 

According to the American Association of Dermatology, several skin infections are pointers for diabetes and prediabetes. These skin infections include

• Diabetic dermopathy (shiny spots)
• Acanthosis nigrans (dark patches on creased skin areas like behind the neck, armpit, and groin)
• Scleredema diabeticorum (hard, thickened skin). 
• Diabetic ulcers
• Eruptive xanthomatosis (outbreak of small bumps)
• Xanthelasma (smooth yellowish bumps or patches on and around your eyelids)
• Acrochordons (skin tags)
• Granuloma annulare (a cluster of small bumps or a raised patch)
• Necrobiosis lipoidica (yellow, reddish, brown, or purplish patches on your skin)

Complications of Prediabetes

If left unchecked, prediabetes can progress to diabetes, which can then result in serious long-term health complications such as:  

• Alzheimer's disease
• Insulin resistance 
• Cancer 
• Depression 
• Hypertension 
• Diabetic kidney diseases
• Diabetic eye diseases
• Skin disorders 
• Diabetic neuropathy (nerve problems)
• Sexual dysfunction 

Some of these complications, like depression and skin disorders, may begin before the development of diabetes mellitus. 

Risk factors for prediabetes

Here are several risk factors that can predispose an individual to develop prediabetes:

Overweight or obesity

People who are overweight or who have obesity, especially those with a body mass index (BMI) greater than 25 kg/m^2, are considered to run a high risk of having prediabetes. 

Obesity is a common underlying cause of insulin resistance and is a major risk factor for prediabetes.

Family history of diabetes mellitus (parent or sibling)

Individuals with a family history of diabetes mellitus stand a higher chance of getting prediabetes. Studies show that an individual whose parents have been diagnosed with type 2 diabetes mellitus has a 40% chance of developing the same condition.

Diabetes during pregnancy (gestational diabetes)

Gestational diabetes is a mild diabetic condition commonly seen in pregnant people. Studies show that those who develop gestational diabetes during pregnancy are likely to develop prediabetes as well as type 1 and especially type 2 diabetes mellitus if their prediabetic condition isn’t treated properly.

High-risk ethnic groups

Individuals with a certain genetic makeup belonging to their ethnicity or race may run a high risk of developing prediabetes.

African Americans, Latin Americans, Native Americans, or Asian/Pacific Islanders have been considered to be the ethnic groups with higher chances of developing prediabetes and type 2 diabetes mellitus.

Hypertension

A 9-year cohort research study on the correlation of hypertension and prediabetes in patients suggests that hypertensive patients run a high risk of developing prediabetes as well as type 2 diabetes mellitus. 

The study further emphasized on age and obesity as common causes of hypertension, which then results in the development of prediabetes and type 2 diabetes mellitus. Furthermore, the coexistence of hypertension and type 2 diabetes mellitus may result in complications like cardiovascular disease(CVD).

Physical inactivity

Living a sedentary life can predispose an individual to develop prediabetes as well as type 2 diabetes mellitus.

A sedentary life is one with little or no physical activity. Watching television all day, for instance, is a common sedentary lifestyle habit. Physical inactivity lowers an individual's metabolic rate, which in time, may result in insulin sensitivity.

Dyslipidemia

This refers to the continuous presence of abnormally high amounts of lipids (fats) in the bloodstream. In patients with dyslipidemia, their high-density lipoproteins (HDL) or good cholesterol levels is less than 40 mg/dl in men and below 50 mg/dl in women. 

In this case, triglyceride (TAG) low-density lipoproteins (LDL) levels, both considered bad cholesterol, are above 160 mg/dl and 250 mg/dl, respectively. Research studies indicate that dyslipidemia may be associated with insulin resistance seen in prediabetic patients. 

Polycystic Ovarian Syndrome

Polycystic ovarian syndrome is a hormonal disorder that affects the ovaries by causing them to enlarge and begin to have small cysts formed on their outer walls.

People with polycystic ovarian syndrome have been recorded to have higher body weight and higher BMIs. They may also experience dyslipidemia and hormonal imbalances, which could eventually result in the development of prediabetes.

Age

Aging is another major risk factor for prediabetes. A study report in the United States stated that people over the age of 65 had a 25% chance of developing type 2 diabetes mellitus.

For people between the ages of 45-64, it was a staggering 17%. This then suggests that an individual's chances of getting prediabetes as well as Type 2 diabetes mellitus increases with age.

Sex/Gender

Recent research studies suggest that people assigned male at birth may be susceptible to developing prediabetes at a younger age and have a lower body mass index (BMI) compared to those assigned female at birth.

However, females, after menopause, undergo rapid hormonal changes. These changes can thus result in weight gain and vascular and inflammatory risk factors, which can be associated with prediabetes.

Other uncommon risk factors that could cause prediabetes include excessive alcohol and tobacco abuse.

Research shows that individuals who smoke and/or drink large amounts of alcohol consistently stand a high chance of developing type 2 diabetes mellitus. This is due to the destruction of beta cells of the pancreas, which produces insulin hormone.

Tests for prediabetes

Certain tests can be performed on an individual to determine if that individual is prediabetic or not. These tests include:  

Fasting plasma glucose test (FPG):

This test requires the absence of food and drink intake, apart from water, within the next 8 to 12 hours before it is carried out on the patient.4 

If results for the FPG test fall between 100 mg/dl to 125 mg/dl, the patient is then diagnosed with prediabetes.

Oral Glucose Tolerance Test (OGTT):

Here, the patient consumes a glucose syrup solution containing 75 g of glucose, before which a blood test is carried out to determine 2-hour plasma glucose (PG). 4

If results for the OGTT fall between 140 mg/dL to 199 mg/dL the patient is then diagnosed with prediabetes.

HbA1C (Glycated hemoglobin)

This laboratory test checks for the average levels of hemoglobin bound to glucose within the last 2 to 3 months.

If results for the HbA1C test should fall between 5.7% to 6.4%, then the patient is diagnosed with prediabetes.

Random Plasma Glucose

This test is carried out randomly to determine the level of plasma glucose in an individual's bloodstream. 

If the results of the random blood glucose test fall between 140 mg/dl to 199 mg/dl, then the patient is diagnosed with prediabetes. 

How to reverse or manage prediabetes

An interesting fact about prediabetes is that it is easily treatable. Common lifestyle changes, the use of prescribed medications, and curbing of certain habits have shown to be some of the natural remedies in helping reverse and prevent prediabetes. Some of the lifestyle changes include; 

• Constant physical exercise: The American Diabetes Association suggests that exercising regularly for 30 minutes each day can help treat prediabetes.
• Weight loss: Burning off 10 to 15 pounds of your current weight can also help in treating prediabetes.
• Dieting: Consuming foods and vegetables rich in fiber can help you stay healthy and fit, improve digestion, and reverse prediabetes. 
• Smoking cessation: Cessation of smoking will also help in the restoration of inflamed or damaged cells, further reversing prediabetes. 
• Medication: Your doctor may also recommend some antidiabetic medications like Metformins, Thiazolidinediones, α-Glucosidase Inhibitors, Incretins, as well as other anti-obesity drugs for you to further speed up your recovery.

It's important to note that strict adherence to these lifestyle changes and prescribed medications may help in speedy recovery from prediabetes. 

When to see a doctor and get tested for prediabetes

If you suspect that you may have prediabetes or you begin to show any or most of the symptoms highlighted in this article, then consult your doctor for professional help. This will enable you to get tested and diagnosed properly. And ascertain if you're truly prediabetic, diabetic, or simply hyperglycemic.