‘Night owls’ have higher risk of type 2 diabetes and heart disease than ‘early risers’?

Researchers at Rutgers University in New Jersey, USA, investigated activity and sleep patterns between ‘waking up early’ and ‘staying up late’ for possible effects on the risk of diseases such as type 2 diabetes and heart disease. , the wake/sleep cycle can cause metabolic differences that can alter the body’s preferences for energy sources.

Metabolic differences associated with each group participating in the study using insulin to promote glucose uptake by cells, facilitating storage and energy use. Those who stayed up late were less able to use fat for energy. This means that fat can build up in your body, increasing your risk of type 2 diabetes and cardiovascular disease. https://physoc.onlinelibrary.wiley.com/doi/abs/10.1113/EP090613

Participants (n=51) were divided into two groups (early and late) based on their ‘chronotype’. They used advanced imaging to assess body weight and body composition, and insulin sensitivity and breath samples to measure fat and carbohydrate metabolism.

Lead author Professor Stephen Mullin of the Rutgers Institute for Translational Medicine and Science told International Labmate about the imaging aspects of the study: Simply put, the DXA method is a non-invasive scan that can tell you not only your body weight, but also the composition of your body weight. Specifically, it provides detailed analysis of adipose tissue, lean body mass and bone density.

“This is clinically important because a person may be considered to have a healthy weight based on a height/weight chart, but have more body fat and less muscle mass. Although considered by some to be, they have a low amount of body fat and a fair amount of muscle mass.

“The technique generally works by passing a low-radiation X-ray beam through tissue. Different absorptions allow the expert/researcher to determine the type and amount of tissue. It is fairly simple to lie down on an empty table, and an imaging device or arm is placed over the person’s head and passed slowly over the body, producing an image on a computer monitor. It takes about 10 minutes or less.”

According to Marin, DXA was used as some evidence to show that people who consider themselves late chronotypes are at higher risk for weight and obesity than their early chronotype counterparts. It also provides researchers with an opportunity to identify what body composition people with early or late chronotypes have, and how body fat and lean tissue relate to health. “Our results suggest that body composition does not necessarily have a direct relationship to health, but rather is related to fat metabolism and insulin sensitivity, so that quality versus quantity, etc. This suggests that other factors in the study may be more important. Further work is needed to confirm this,” he added.

Participants were monitored for one week to assess daily activity patterns. They had to eat a calorie- and nutrition-controlled diet and fast overnight to minimize the effect of diet on outcomes. The test was done at rest before doing it twice. Aerobic fitness levels were tested through an incline challenge in which participants increased the incline by 2.5% every 2 minutes until fatigue was reached.

Researchers found that early risers used more fat for energy, both at rest and during exercise, and were also more insulin sensitive than night owls. Night owls were found to be insulin resistant. That is, their bodies needed more insulin to lower blood sugar levels, and their bodies preferred carbohydrates as an energy source over fat. disorders may be detrimental because they indicate an increased risk of type 2 diabetes and/or heart disease. We do not know and need further investigation.

“The difference in fat metabolism between ‘early risers’ and ‘night owls’ is that our body’s circadian rhythms (wake/sleep cycles) can affect how our bodies use insulin.” A sensitive or impaired ability to respond to insulin hormones has a significant impact on our health. This observation enhances our understanding of how our body’s circadian rhythms affect our health. It suggests that chronotype can be used as a factor to predict an individual’s disease risk,” said Prof. Malin.

“We also found that early risers were more physically active and had higher fitness levels than sedentary night owls. More research is needed to see if exercising early in the day magnifies the health benefits.”

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