A weekend lie in after a Friday or Saturday night out may send you to an early grave, according to new research.

Staying up into the early hours - and then getting up later than during the week - can cause heart disease, warn scientists.

Known as 'social jet lag', it raises the risk of Britain's No. 1 killer by eleven percent for every hour's difference in sleep patterns.

The study published in Sleep found it is associated with poorer health, worse mood and increased sleepiness and fatigue.

Lead author Sierra Forbush said the phenomenon has emerged as an important 'body clock marker' for health.

Changing your circadian rhythm between weekends and the working week has consequences, she warned.

The term 'social jet lag' was coined five years ago because It causes similar symptoms to travel jet lag.

Just as cross-continental flights can disrupt the body clock by sending passengers abruptly across several time zones, social jet lag wreaks havoc with circadian rhythms.

Ms Forbush, an undergraduate research assistant in the Sleep and Health Research Program at the University of Arizona, Tucson, explained: "These results indicate sleep regularity, beyond sleep duration alone, plays a significant role in our health.

"This suggests a regular sleep schedule may be an effective, relatively simple, and inexpensive preventative treatment for heart disease as well as many other health problems."

Her findings follow a study 18 months ago that found social jet lag can trigger heart disease - as well as diabetes.

Social jet lag occurs when you go to bed and wake up later on weekends than during the week.

Each hour of social jet lag is also linked with an eleven percent increase in the likelihood of heart disease.

These effects are independent of sleep duration and insomnia symptoms, which are related to both social jet lag and health.

Ms Forbush and senior author Dr Michael Grandner, director of the Sleep and Health Research Program used data from the community based Sleep and Healthy Activity, Diet, Environment, and Socialisation (SHADES) study.

They analysed survey responses from 984 adults between the ages of 22 and 60 years.

Social jet lag was assessed using the Sleep Timing Questionnaire and was calculated by subtracting the midpoint of their weekday sleep cycle from the midpoint of their weekend one.

Overall health was self reported using a standardised scale, and survey questions also assessed sleep duration, insomnia, cardiovascular disease, fatigue and sleepiness.

The American Academy of Sleep Medicine recommends that adults should sleep 7 or more hours per night on a regular basis to promote optimal health.

In addition to adequate duration, healthy sleep requires good quality, appropriate timing and regularity.

In December 2015 another US study of around 450 middle aged adults found those with the biggest shift in sleep routines between workdays and days off were more likely to have health problems that are risk factors for diabetes and heart disease.

The symptoms included extra girth around the midsection and higher levels of sugars and fats in the blood.

The participants with ‘social jet lag’ also had low levels of high density lipoprotein cholesterol – which is the ‘good kind’ of cholesterol that works to prevent damage to blood vessels.

Doctors have warned social jet lag is even more harmful than ordinary jet lag, because the former involves people shifting in and out of different routines based on work schedules. The latter allows them to adjust to a new routine.

ENDS