03 Jul Sleep is important for …weight loss?
Although adults need at least 7 hours of uninterrupted sleep per night to feel rested, many
individuals are unable to achieve this ideal. Statistics show that in the U.S. alone, in 2017, as
many as 36% of surveyed respondents did not feel rested upon waking up in the morning, which
suggests that they were not getting enough — or good enough — sleep.
Insufficient sleep, recent studies argue, may affect circulation, aspects of memory, and even our
Now, a study that features in the International Journal of Obesity has found a link between
insufficient or disrupted sleep and another issue — weight loss. The results showed that
overweight people who did not sleep well lost less weight than their peers who had no sleep
The research comes from the Human Nutrition Unit of the Rovira I Virgili University in
Tarragona, Spain, and other collaborating institutions.
The rise in obesity prevalence rates over the past decades parallels an epidemic of sleep
disturbances," Prof. Jordi Salas-Salvadó and colleagues write.
In this context, the PREDIMED-Plus, a new ongoing primary cardiovascular prevention trial
based [on] an intensive weight-loss lifestyle intervention program, provides an unprecedented
opportunity to examine the 12-month changes in weight and adiposity measures between those
participants with short or adequate sleep duration and between those with low or high sleep
variability," they continue.
PREDIMED-Plus is a clinical trial that studies the health effects of following the Mediterranean-
style diet in a Spanish cohort. The results of the current research are part of this ongoing trial.
In the current research, Prof. Salas-Salvadó and colleagues analyzed the medical data of 1,986
individuals with a mean age of 65 years over the course of a year.
All of these participants were overweight or had obesity at baseline, and they also had metabolic
syndrome, a cluster of health risk factors that include high blood pressure (hypertension),
increased levels of insulin (hyperinsulinemia), low glucose tolerance, and abnormal levels of
blood lipids (dyslipidemia).
For the entire year, these volunteers participated in an intensive weight loss program that
included following a low-calorie Mediterranean-type diet, boosting levels of physical activity,
and participating in behavioral support sessions that aimed to improve habits and lifestyles.
The investigators noted any changes in body weight and body fat (adiposity) throughout the year.
They also monitored participants' reported sleeping patterns.
At the end of the study period, Prof. Salas-Salvadó and the team found that the participants who, at
baseline reported not sleeping for the same number of hours every night — a phenomenon
called high sleep variability — had lost less weight after a year than those who reported a regular
sleep pattern; they also experienced less of a reduction in body mass index (BMI).
In addition, the results showed that people who tended to sleep for less than 6 hours each night
experienced less of a reduction in waist circumference than those who slept 7–9 hours.
The findings of our study highlight the importance of sleep characteristics on weight and
adiposity responses to lifestyle intervention programs in elders with metabolic syndrome," the
For this reason, they encourage weight loss programs to monitor participants' sleeping patterns
and to consider improving sleep hygiene as part of the intervention.