Not Just Sugar: Apollo Neurologist Explains 5 Major Causes of Insulin Resistance

New Delhi | 7 March 2026 Insulin resistance, a key factor behind the development of diabetes, is often linked only to excessive sugar consumption. However, according to Sudhir Kumar, the issue is far more complex. In a recent post on X, the neurologist from Apollo Hospitals explained that insulin resistance is influenced by several lifestyle and biological factors. He noted that it is “not simply about sugar intake but more about movement, sleep, fat distribution, food quality and stress,” highlighting that many of these factors can be improved with better metabolic health habits. One of the biggest contributors to insulin resistance is belly fat, particularly visceral fat that accumulates around internal organs. This type of fat can interfere with how the body responds to insulin. Dr Kumar explained that a person may not appear overweight yet still be “metabolically unhealthy.” This means body weight alone does not always reflect metabolic health, as fat distribution plays a significant role. A sedentary lifestyle is another major driver. Many people, especially those working in offices or living in urban settings, spend long hours sitting with very little physical activity. Dr Kumar emphasized the importance of movement, saying, “Muscle is your largest glucose-burning organ.” When the body remains inactive, muscles absorb less glucose from the blood, forcing the body to produce more insulin and increasing the risk of insulin resistance. Diet and sleep habits also play an important role. Frequent consumption of ultra-processed and high-glycemic foods can cause repeated spikes in blood sugar and insulin levels. Over time, this pattern makes insulin receptors less responsive. Lack of sleep and long-term stress can further worsen the situation by increasing cortisol levels. Dr Kumar warned that “High cortisol levels directly worsen insulin sensitivity,” adding that adults should aim for at least seven hours of sleep each night. Genetics can also influence the risk. According to Dr Kumar, many people from South Asians may develop insulin resistance at lower body mass index levels compared with other populations. While family history can increase vulnerability, lifestyle choices such as physical activity, balanced nutrition, and proper sleep still play a major role in determining long-term health outcomes. : Not Just Sugar: Apollo Neurologist Explains 5 Major Causes of Insulin Resistance Insulin resistance, a major factor behind the development of diabetes, is often blamed only on eating too much sugar. However, Sudhir Kumar from Apollo Hospitals says the issue is more complex. In a recent post on X, he explained that insulin resistance is influenced by several factors and is “not simply about sugar intake but more about movement, sleep, fat distribution, food quality and stress.” One of the main drivers of insulin resistance is belly fat, especially visceral fat that builds up around internal organs. This type of fat can disrupt how the body responds to insulin. Dr Kumar noted that a person may look normal in weight but still be “metabolically unhealthy” if excess fat is stored around the organs. Another major cause is a sedentary lifestyle. Many people spend long hours sitting at work or at home, which reduces the body’s ability to use glucose effectively. Dr Kumar explained the importance of movement, saying, “Muscle is your largest glucose-burning organ.” Lack of physical activity leads to poor glucose uptake and increases insulin production. Diet, sleep and genetics also play important roles. Frequent intake of ultra-processed foods can cause repeated spikes in blood sugar, while poor sleep and stress raise cortisol levels. Dr Kumar warned that “High cortisol levels directly worsen insulin sensitivity.” He also added that people from South Asians may develop insulin resistance at lower BMI levels, making healthy lifestyle habits even more important.