Overnight contact lenses are convenient, but it is also risks for eyes. I read an article about overnight contact lenses, the article wrote that researchers found that people wear overnight contact lenses was more likely to infections. So, if you want to keep your eye health, you'd better wear prescription eyeglasses or regular contact lenses and take off your contact lenses every day.
The traditional overnight contact lenses are not so safe because they can develop bacteria between the lenses and the eyes during sleep. When your eyes are closed, less oxygen will reach your corneas so that your eyes can easily get infected. However, there are new types of overnight contact lenses which apply advanced technology to make them safer to wear overnight than the traditional ones.