Common night time habit is increasing your risk of type 2 diabetes

Many of us develop habits we know aren’t particularly good for us. And in recent years there has been a lot of discussion about the impact of mobile phones and screen time on our sleep health.

It has been shown that staying up late on your devices could be making it harder for you to not only get to sleep, but also ruining the quality of your sleep.

Now researchers are saying that exposure to lights at night could have an even more dangerous side effect. According to a new study, published in The Lancet Regional Health, nighttime light exposure can increase your risk of developing type 2 diabetes.

Diabetes is a condition that causes your blood sugar to become too high. Type 2 is far more common than type 1 diabetes, affecting around 90 percent of patients.

Typical causes of type 2 diabetes include being overweight and not exercising enough. However, it can also be genetic.

Therefore, health bodies urge prediabetic people to maintain a healthy weight and watch what they eat. But now researchers, based in Australia, the UK and the US, say avoiding bright lights at night should be another recommendation.

Andrew Phillips, an associate professor from Flinders University College of Medicine and Public Health in Australia, explained: “The results showed that exposure to brighter light at night is associated with a higher risk of developing diabetes, with a dose-dependent relationship between light exposure and risk.”

He added: “The results showed that exposure to brighter light at night is associated with a higher risk of developing diabetes, with a dose-dependent relationship between light exposure and risk.

“Our findings suggest that reducing your light exposure at night and maintaining a dark environment may be an easy and cheap way to prevent or delay the development of diabetes.”

As part of the study, the team analysed personal light exposure patterns from approximately 85,000 people and 13 million hours of light sensor data. 

People who did not have type 2 diabetes wore a tracker on their wrists to collect light levels during the day and night. 

They were then tracked for nine years to see if they later developed type 2 diabetes.

The data showed that people who were exposed to bright lights between 12.30am and 6am were more likely to develop the condition. 

This link remained regardless of how much light people were exposed to during the day.

Even when the researchers took into account lifestyle habits, sleep patterns, shift work, diet, and mental health, the link remained. 

They theorised that bright night lights raise a person’s risk of type 2 diabetes by disrupting their circadian rhythms.

Your circadian rhythm is the internal clock that tells the body when it’s time to feel awake or tired, that aligns with the 24-hour cycle of light and darkness. 

Messing with this biological clock affects the normal rhythm of other bodily processes, including glucose metabolism and insulin secretion levels, which regulate blood sugar.

According to the NHS, you are also more at risk of developing type 2 diabetes if you:

• Are over 40 years old, or over 25 if you’re from an Asian, Black African or Black Caribbean ethnic background
• Have a close relative with diabetes (such as a parent, brother or sister)
• Are overweight or living with obesity or are not very physically active
• Are from an Asian, Black African or Black Caribbean ethnic background.

Common signs of diabetes include:

• Urinating more than usual
• Feeling thirsty all the time
• Feeling very tired
• Losing weight without trying to
• Itching around your penis or vagina, or repeatedly getting thrush
• Cuts or wounds taking longer to heal
• Blurred vision.

If you experience symptoms you should speak to your GP.