WASHINGTON (AP) – Being a night owl can be bad for your heart. Related: Night Owls Face Higher Depression Risk. Over 14 years, the night owls had a 16 percent higher risk of a first heart attack or stroke compared to the average population, the researchers found. "It comes down to the problem of a night owl trying to live in a morning person's world. But Kianersi said one of the best steps to protect heart health – for night owls and anyone – is to quit smoking.