People who get less than seven or eight hours of sleep at night are at increased risk of cardiovascular disease, including heart disease, heart attack, and stroke. Worse yet, researchers now say this can happen in just one week.

There are two types of cholesterol that circulate in the blood: LDL cholesterol, which is the “bad” cholesterol that builds up in the heart’s coronary arteries, causing heart disease; and HDL cholesterol, which can help whisk it away, reducing cardiovascular risk.

Researchers from the University of Helsinki analyzed people sleeping in a laboratory. They looked at the impact of sleep deprivation on genes regulating the transport of cholesterol around the body, and on the actual levels of cholesterol in the blood.

They found that the genes regulating the transport of cholesterol around the body are less active in sleep-deprived people than those who get a good night’s rest.

They also found that these people had higher levels of LDL cholesterol in their blood and lower levels of HDL cholesterol.

Most importantly, they discovered that such changes occurred only after one week. The study appeared in Scientific Reports.

Sleep disorders like insomnia are a serious problem in the U.S., but many of us shortchange ourselves on sleep by choice, going out too late or staying up watching late-night television.

Try turning in an hour early every night — you’ll see how much better you feel in the morning and you’ll be conquering heart disease as well.