What causes prediabetes?

Prediabetes rarely comes from a single cause. It usually develops when several risk factors build up over time and the body becomes less sensitive to insulin – the hormone that helps move sugar from the blood into your cells.

Insulin resistance and extra weight

A central mechanism behind prediabetes is insulin resistance. Muscle, liver and fat cells stop responding properly to insulin. The pancreas has to produce more and more insulin to keep blood sugar in range.

Extra fat around the abdomen – a larger waist circumference – is especially linked to insulin resistance. Over time, the pancreas can struggle to keep up, and fasting glucose or A1C slowly drift into the prediabetes range.

Everyday habits that push risk higher

Many day-to-day habits gently push metabolism toward or away from prediabetes. Patterns that typically increase risk include:

• Very little movement – long hours sitting, minimal walking, little or no structured exercise.
• Frequent sugary drinks and ultra-processed snacks – regular soda, energy drinks, pastries, sweets and fast food.
• Large portions and late-night eating – especially when combined with low activity throughout the day.
• Chronic stress and poor sleep – stress hormones and sleep loss can make the body more resistant to insulin.
• Smoking – daily smoking is associated with higher risk of type 2 diabetes and cardiovascular disease.

Factors you cannot fully control

Some drivers of prediabetes are not your choice, but they still shape your baseline risk:

• Family history – having a parent or sibling with type 2 diabetes increases lifetime risk, even with a healthy lifestyle.
• Age – risk gradually rises from the mid-30s and more clearly after age 45–50.
• Ethnicity – some populations develop type 2 diabetes at a lower BMI or younger age.
• Past gestational diabetes – diabetes during pregnancy raises the chance of later prediabetes and type 2 diabetes.
• Polycystic ovary syndrome (PCOS) – often associated with insulin resistance in women.

Hormones, organs and hidden contributors

Prediabetes is a whole-body condition. Several organs and hormones are involved:

• Liver – excess fat in the liver (fatty liver) changes how glucose is released into the bloodstream.
• Pancreas – beta cells may slowly lose their ability to produce enough insulin.
• Thyroid and other hormones – thyroid disorders, long-term steroid use and some medicines can alter how your body handles glucose.
• Chronic low-grade inflammation – linked with obesity, inactivity and some metabolic conditions.

You can still tilt the odds in your favour

You cannot change your age or genetics, but you can influence many of the daily drivers of insulin resistance. Even modest, realistic changes – more steps, fewer sugary drinks, slightly smaller portions, better sleep – can gradually move your risk in a better direction.

If your SugarRisk index or lab values worry you, use them as the start of a calm conversation with your doctor or nurse. Together you can decide which tests and lifestyle changes matter most for you.