Poor sleep is linked to a range of health issues, including diabetes. But can a mild sleep deficit hurt your health? A recent study suggests that mild chronic sleep deprivation can increase insulin resistance in women, posing a potential risk for type-2 diabetes.

Columbia University researchers found that women who missed just 90 minutes of sleep over six weeks had a 12% increase in fasting insulin levels compared to those who maintained sufficient sleep. The effect of sleep deficit was particularly high in postmenopausal women, with a fasting insulin level raised by 15%. The findings were published in the journal Diabetes Care.

Hyperinsulinemia or increased insulin levels is connected to insulin resistance, a condition in which the body does not respond adequately to insulin, the hormone responsible for blood sugar regulation.

The recommended amount of sleep for a healthy adult is between seven and nine hours every night. However, about one-third of adults in the U.S. fail to meet the requirement.

For the study, the researchers recruited 38 healthy women, including 11 postmenopausal women, who routinely slept at least seven hours daily. Women were specifically chosen as the subjects, as the researchers believe that sleep deficit has a greater impact on women's cardiometabolic health than that of men.

"Throughout their lifespan, women face many changes in their sleep habits due to childbearing, child-rearing, and menopause. And more women than men have the perception they aren't getting enough sleep," said study leader Marie-Pierre St-Onge in a news release.

During the study, participants were randomly assigned to two phases, each spanning six weeks. In one phase, the participants continued their routine sleep, while in the other, they delayed sleep for 90 minutes every night, shortening total sleep to around six hours. The sleep schedule was verified using wearable tracking devices. The insulin, glucose, and body fat of the participants were also measured.

Researchers said that while the average blood sugar levels remained stable for all participants throughout the study, there was an overall increase in insulin resistance of nearly 15% and more than 20% among postmenopausal women.

"The fact that we saw these results independent of any changes in body fat, which is a known risk factor for type 2 diabetes, speaks to the impact of mild sleep reduction on insulin-producing cells and metabolism," St-Onge said. "The bottom line is that getting adequate sleep each night may lead to better blood sugar control and reduced risk for type 2 diabetes, especially among postmenopausal women."