Risk Factors for Type 2 Diabetes: From Lifestyle to Genetics

Type 2 diabetes mellitus (T2DM) is often called a “lifestyle disease,” but that is only half the truth. It develops as a result of a complex interaction between genetic predisposition and external triggers. Understanding the risk factors is the first step toward preventing the disease or slowing its progression in people who have already been diagnosed.

All risk factors are divided into non-modifiable (those that cannot be changed) and modifiable (those that can and should be influenced).

1. Non-Modifiable Factors (Given Conditions)

These factors must be taken into account, but their presence is not a sentence — rather, it is a reason for more careful prevention.

• Genetics and family history. This is the strongest risk factor. If one parent has type 2 diabetes, the child’s risk increases by 30–40%. If both parents are affected, the risk reaches 70–80%. What is inherited is not the disease itself, but characteristics of carbohydrate metabolism that make tissues resistant to insulin (insulin resistance).
• Age over 45 years. With age, cell sensitivity to insulin naturally declines, and pancreatic function worsens. However, in recent decades, type 2 diabetes has become increasingly common among younger individuals and is now seen even in obese adolescents.
• Ethnic background. Certain ethnic groups have a higher predisposition, including people of South Asian, Latin American, and African American descent, as well as Indigenous northern populations (for example, the Chukchi or Eskimos after adopting a Western-style diet).
• History of gestational diabetes. If a woman had diabetes during pregnancy or gave birth to a baby weighing more than 4.5 kg, her future risk of developing T2DM increases by 7–10 times.

2. Modifiable Factors (Within Our Control)

Prevention and treatment of diabetes are primarily based on these factors. By addressing them, it is possible to delay the disease for decades or even achieve long-term remission.

• Abdominal obesity (the most important factor!). Fat accumulates not under the skin, but around internal organs (visceral fat). This fat actively releases pro-inflammatory substances that block insulin receptors. Criterion: waist circumference greater than 94 cm in men and greater than 80 cm in women.
• Physical inactivity (low physical activity). Muscles are the main consumers of glucose in the bloodstream. With a sedentary lifestyle, muscle cells become “lazy” and stop responding effectively to insulin. Just 30 minutes of walking per day can reduce the risk by 30–40%.
• A high-glycemic-index diet. Constant consumption of refined carbohydrates (white bread, sweets, sugary drinks, potatoes) forces the pancreas to work excessively hard. Eventually, it becomes exhausted.
• Arterial hypertension (blood pressure >130/85 mmHg). High blood pressure and diabetes are “neighbors” within metabolic syndrome. Hypertension accelerates atherosclerosis and impairs blood supply to tissues, which worsens insulin resistance.
• Dyslipidemia (unhealthy cholesterol profile). Low HDL (“good” cholesterol) and high triglyceride levels are markers of metabolic disturbances that commonly accompany prediabetes.
• Chronic stress and sleep deprivation. Cortisol (the stress hormone) increases blood glucose levels. Chronic sleep deprivation (less than 6 hours per night) reduces insulin sensitivity by 30%.

Risks Created by Diabetes Itself (A Vicious Cycle)

Once type 2 diabetes has developed, secondary risk factors emerge that accelerate complications:

• Persistent hyperglycemia (high blood sugar). Glucose “sticks” proteins together (a process called glycation), damaging the blood vessels of the eyes, kidneys, and legs.
• Resistance to treatment. Delayed initiation of insulin therapy or refusal to take medications leads to chronically elevated blood sugar levels that cannot be controlled by diet alone.
• Smoking and alcohol consumption. Smokers with diabetes have a fivefold higher risk of heart attack and leg gangrene. Alcohol first causes a sharp rise and then a dangerous drop in blood sugar (hypoglycemia).

The Main Idea

If you have a family history of diabetes (a non-modifiable factor), it means you should avoid obesity and physical inactivity (modifiable factors). In type 2 diabetes, genetics “loads the gun,” while lifestyle “pulls the trigger.”

Risk Assessment Scale (IDF – International Diabetes Federation)

• High risk: age + excess weight + family history.
• Very high risk: the above factors + high blood pressure + low physical activity.
• Critical risk: all of the above + impaired fasting glucose or prediabetes.

The only way to break this chain is through regular glucose monitoring, weight reduction by 5–7%, and daily physical activity.