Control blood sugar with 7-hour and 18 minutes of sleep daily, says new study: What’s the link?

Understanding the sleep metabolism connection

Sleep is not just about rest for the brain. During sleep, the body carries out several essential processes that regulate hormones, metabolism and energy balance. Hormones such as cortisol, insulin and those related to growth follow a natural rhythm that is closely linked with the sleep–wake cycle. When a person does not get enough sleep, this hormonal balance gets disrupted. As a result, the body may become less efficient at processing glucose, leading to higher blood sugar levels.

On the other hand, excessive sleep may also signal underlying health problems or metabolic changes that affect how the body regulates glucose.

The sweet spot

On average, a 7.3-hour daily sleep duration is the sweet spot for reducing the risk of insulin resistance. Insulin sensitivity improved as people approached the 7.3-hour mark, then worsened when they slept beyond that. Women and adults ages 40 to 59 were especially prone to insulin resistance if they slept more than 7.3 hours on weekdays.

While the exact number of hours may vary slightly from person to person, most adults benefit from maintaining a consistent sleep duration within the 7–8-hour range.

What about weekend catch-up sleep?

Many people try to compensate for weekday sleep loss by sleeping longer on weekends. The study suggests that moderate catch-up sleep — around one to two extra hours — may help those who are consistently sleep deprived during the week.

However, sleeping significantly longer on weekends may not be beneficial, especially for people who already get adequate sleep during the week. Large shifts in sleep schedules can disrupt the body’s internal clock, a phenomenon often called “social jet lag.” This disruption can negatively impact metabolism and blood glucose regulation.

Consistency matters as much as duration

Maintaining a regular sleep schedule may be just as important as getting the right number of hours. Going to bed and waking up at similar times each day helps keep the body’s biological clock stable, supporting better hormone regulation and metabolic health.

Irregular sleep patterns have been linked to reduced glucose tolerance and lower insulin sensitivity, even among otherwise healthy individuals.

Simple steps to improve sleep health

Improving sleep habits does not necessarily require drastic lifestyle changes. Some practical strategies include maintaining a fixed bedtime and wake-up schedule, limiting screen exposure before bedtime, avoiding heavy meals and caffeine late in the evening and creating a comfortable, quiet sleeping environment. Most importantly, manage stress through relaxation techniques or physical activity.

The bigger picture

Sleep should be viewed as an essential component of preventive health, along with balanced nutrition and regular physical activity. But that’s what we tend to negotiate the most.

(Dr Saptarshi Bhattacharya is senior consultant, Endocrinology, Indraprastha Apollo Hospitals, New Delhi)