To ensure good sleep, people are advised to set a fixed bedtime, limit exposure to blue light, and avoid drinking coffee, tea or alcohol close to bedtime. These are all habits that are harmful to sleep and can lead to many other health problems in the long run, according to the health website Healthline (USA).

However, sleeping too little or too much can increase blood cholesterol levels. The US Centers for Disease Control and Prevention (CDC) recommends that people between the ages of 18 and 60 get at least 7 hours of sleep per night. Sleeping more or less than this amount over a long period of time can cause fluctuations in blood cholesterol levels.

A study published in the journal Sleep analyzed survey data from Japanese citizens. In the survey, participants answered questions about their physical condition, diet, and lifestyle habits, including how many hours they slept each night. They also had blood tests to check their cholesterol levels.

The research team found that people who slept less than 5 hours a night tended to have lower levels of "good" HDL cholesterol, while those who slept more than 8 hours a night had higher levels of "bad" LDL cholesterol.

Currently, scientists still do not know the real cause of fluctuations in blood cholesterol when sleeping too much or too little. However, the hypothesis is that it is most likely due to the impact of sex hormones between men and women as well as the body's metabolic function.

This is especially true since our cholesterol metabolism typically occurs at night, which is why many cholesterol medications are prescribed to be taken before bed. However, lack of sleep or too much sleep can interfere with cholesterol metabolism, especially in people who are overweight, obese, or have high blood pressure.

To control blood cholesterol levels, in addition to getting enough sleep, experts recommend that people eat healthy, exercise regularly, avoid alcohol, and take medication when necessary. Good cholesterol control can help prevent many cardiovascular problems, including heart attacks and strokes, according to Healthline .