- Researchers analyzed data from nearly 800 people between the ages of 50 and 64
- Hardened arteries were seen in 22% of early birds, but in almost 41% of night owls
Night owls may have almost twice the risk of hardened arteries as early birds.
Hardened arteries, caused by a buildup of fatty deposits in the blood vessels, are more common in older people with high blood pressure and cholesterol, and increase the risk of heart attack or stroke.
Researchers looked at 771 people aged 50 to 64 to see if the condition was more common among night owls, who tend to wake up later and go to bed later and are more energetic in the afternoon and evening.
They found that people who said they were real night owls were 90 percent more likely to have hardened arteries than those who were real early risers.
About 17 percent of people say they are definite night owls, with this category excluding people who say they are night owls “to some extent.”
Researchers looked at 771 people aged 50 to 64 to see if the condition was more common among night owls, who tend to wake up later and go to bed later and are more energetic in the afternoon and evening. They found that people who said they were real night owls were 90 percent more likely to have hardened arteries than those who were real early risers.
There is some evidence that being a night owl, rather than being particularly active during the day as humans have evolved, can work against our natural body clock.
This difference in timing is linked to high blood pressure and inflammation, which can damage the arteries and cause them to harden.
The fatty deposits that cause the hardness can then rupture, causing blood clots that can lead to heart attacks and strokes.
However, night owls also tend to have more unhealthy lifestyles, such as eating poorly, which could also increase the risk of hardened arteries.
Mio Kobayashi Frisk, who led the research at the University of Gothenburg in Sweden, said: 'People who are night owls should be aware of the possible link with hardened arteries, and perhaps try not to go to bed too late if they are tired .
'Because they may be in a risk group for cardiovascular disease, they may want to consider lifestyle changes such as eating healthy and getting enough sleep and exercise.'
The study, published in the journal Sleep Medicine, looked at people who were asked in previous research whether they were a “definitely” morning or evening person, a morning or evening person “to some extent,” or neither.
Hardened arteries were seen in about 22 percent of early risers, but in almost 41 percent of true night owls.
Those who said they were a definite evening person were 90 percent more likely than a true morning person to have hardened arteries, after taking into account other factors including their weight, physical activity and alcohol consumption.
Researchers then looked at people's risk of developing cardiovascular disease over the next ten years, which is determined by their age, gender, blood pressure, level of 'bad' cholesterol and smoking habits.
Obvious night owls at high risk for cardiovascular disease were 15 times more likely to have hardened arteries than other people at low risk for cardiovascular disease.