Variability in sleep patterns linked to weight gain

By REGINA PALATINI Senior Staff Writer

The next time you pull an all-nighter to prepare for a test you may unknowingly be setting yourself up to gain weight. A new study suggests that the “freshman 15,” those extra pounds that many students gain during freshman year, may be caused by the erratic sleep patterns experienced during a student’s first year at college.

Sleep is one of the least understood events that we experience in our daily lives. However, its importance becomes clear when we lose it. The way it affects our mood is easy to describe, but the medical mechanisms of sleep are not well understood. Scientists have begun to shed light on the vital and sometimes elusive phenomenon of sleep with the advent of imaging methods and technology such as positron emission tomography (PET) and functional Magnetic Resonance Imaging (fMRI).

As many attempt to cram in as many activities as possible into one 24-hour day, the nation as a whole is sleeping less.

College students are notorious for not getting a lot of sleep. According to the University of Georgia (UGA) Health Center they average about six hours per night. The Health Center reports that their research suggests that lack of sleep can affect college students’ health, mood, GPA and safety. According to a health survey administered at UGA every two years, one in four students indicate that lack of sleep has impacted their academic performance in a negative way.

So how can poor sleep habits also affect our weight? The answer lies in how our bodies react to sleep variability.

The Sleep for Science Program at Brown University studied 132 freshmen. In nine weeks more than half of the participants had gained about six pounds. The students gaining the weight were the ones who slept less than nine hours and 15 minutes per night, which is the recommended amount for teens. The Brown researchers also discovered a new parameter associated with weight gain — how often a student’s bedtime and waking time altered. In other words, this is their sleep variability.

Adult workers typically wake at about the same time at least during the five days of their workweek whereas students generally wake up at irregular times.

As these students’ schedules change during the week, their sleeping patterns tended to vary as well. Students would wake early on days they had an early morning class and sleep till later on days when their first class began later. Their evening activities also kept them awake later than usual during some evenings.

Male freshmen suffered from the impact of sleep variability more than females. Their bedtimes and wake times shifted daily by an average of two hours and 37 minutes. According to the Brown study, this shift was similar to adjusting to jet lag every day.

Their metabolic rates also readjusted as their body clocks adjusted every day. Researchers stated in a recent study in the journal PLOS One that teens seek more high-calorie candy and desserts when they are sleep deprived.

“Variability is taking the field of sleep research a step further,” Dean W. Beebe of Cincinnati Children’s Hospital Medical Center said in a press release.

Past researchers tended to measure the amount of time a person slept. Beebe reports that measuring daily sleep variability makes sleep studies more complex but also adds valuable information to them.

So it may be time to change your sleeping habits the next time you notice your favorite jeans fitting tighter than usual.