Night Owls At Higher Risk Of Developing Heart Disease And Diabetes


A new study suggests that people that prefer to stay up late, prefer late nights, sleeping in and are basically considered night owls have a higher risk of certain chronic health problems such as heart disease and type 2 diabetes, unlike those that prefer to wake up earlier in the morning.

These differences in what’s known as the so-called sleep chronotypes, which are the natural sleep-wake cycles that program the body’s biological clock, have been associated with the risk of many chronic health issues, such as type 2 diabetes, obesity, digestive disorders, fertility issues, and mental illness. However, a lot of the research looks at what happens when people can’t sleep due to their bodies being naturally inclined to be that way, which is a common problem for shift workers.

This new study decided to take a different approach by focusing on those that don’t follow their natural sleep-wake cycles, a term that is also known as one’s circadian rhythm. The scientists studied two distinct sleep chronotypes: ‘24 “early birds” who were most alert in the mornings and tended to go to bed earlier, and 27 “night owls,” who were sharpest later in the day and tended to stay up late.’

What the researchers found overall is that the so-called night owls had less ability to use fat as an energy source, which means that the fats not only accumulated in the body, but raised the risk of type 2 diabetes and cardiovascular disease. These study results were published in the September 19 copy of the journal Experimental Physiology.

The study also found that ‘these metabolic differences can be explained by how well people with different sleep chronotypes use the hormone insulin to turn glucose or the sugars in the blood from foods we eat, into energy that cells can burn immediately or store for later.’

Moreover, the study also discovered that the early birds managed to use more efficiently for energy than those who were considered night owls do, allowing them to go through their energy source and then burn off even more stored fat for energy as well. In contrast, the night owls showed that the couldn’t efficiently use glucose or burn off as much as their stored fat.

Lead study author and associate professor in the department of kinesiology and health at Rutgers University in New Brunswick, New Jersey, Steven Malin, PhD, said in a statement, “The differences in fat metabolism between ‘early birds’ and ‘night owls’ shows that our body’s circadian rhythm could affect how our bodies use insulin.”

Dr. Malin added, “A sensitive or impaired ability to respond to the insulin hormone has major implications for our health.”

In order to get these results, the research team used advanced imaging to properly assess the body composition of the tested participants for their insulin sensitivity. They also used breath samples to measure the fat and carbohydrate metabolism. The scientists also monitored their activity levels, while also providing them with all their meal to control their energy intake, while conducting treadmill tests to determine their aerobic fitness levels.

As for the early birds, the study found that they used more fat for energy when they were at rest, as well as during these exercise tests. The early birds were also more sensitive to insulin, which meant that they were better at using the hormone to lower their blood sugar, which in turn was more successful at burning fats for energy.

Meanwhile, the night owls were insulin resistant, which meant that they need more of the hormone to lower their blood sugar levels that usually tend to store more fats.

Dr. Malin shared, “This observation advances our understanding of how our body’s circadian rhythms impact our health. Because chronotype appears to impact our metabolism and hormone action, we suggest that chronotype could be used as a factor to predict an individual’s disease risk.”