A new study identifies four key factors that make all the difference in waking up well in the morning: switching to your lunchtime alarm and freshening up at one end of the scale, or battling lightheadedness and repeated taps of the snooze button at the other.
The team behind the study say that these factors, regardless of which genetics an individual is born with, can all be altered to some extent to ensure we get a better start in the morning.
“Why do we humans fluctuate in our vigilance from day to day?” asked the research team led by neuroscientist and sleep researcher Raphael Vallat of the University of California (UC) Berkeley in their published paper.
“Why do we wake up one morning feeling alert, yet another morning, do we struggle with that level of alertness upon waking?”
A total of 833 people participated in the study, most of whom were twins (this helped the researchers filter out variations due to genetics). For two weeks, food intake, physical activity, sleep patterns and glucose levels were recorded, while the volunteers also rated their alertness at different times of the day.
The first factor that matters is the sleep profile: the duration, timing and efficiency of sleep during the night. Sleeping longer and waking up later than normal were both associated with better morning alertness.
The second factor was the amount of exercise people got the day before. Higher levels or movement during the day (as well as less physical activity at night) were associated with more continuous and less interrupted sleep, which in turn it provided for greater vigilance on the part of the participants in the morning.
Thirdly, there was the breakfast. Morning meals with more carbohydrates led to better levels of alertness, while more protein had the opposite effect. By keeping the calories in the meals provided the same, the researchers were able to focus on the nutritional content of what was being eaten.
Finally, an increase in blood sugar levels after breakfast, tested using a pure glucose liquid drink, was associated with reduced alertness. A lower glycemic response, seen after participants ate a carbohydrate-rich breakfast, improved alertness.
In other words, how the body processes food matters, and too much sugar leads to a sugar crash rather than a sugar rush in the morning.
Other factors at play in regards to daily vigilance included the mood and age of the volunteers, although these are not as manageable as what time you go to bed and what you eat for breakfast.
“Our results reveal a number of key factors associated with vigilance that, for the most part, are not fixed. Instead, most of the factors associated with vigilance are modifiable and therefore permissive for behavioral intervention,” write Vallat and colleagues.
The team is keen to investigate some of the mechanisms behind these associations to gather more accurate data; participants reported their alert levels, which weren’t measured using any scientific tools.
That said, in addition to reporting their daily behaviors, the participants ate standardized meals and wore an accelerometer wristwatch (to measure sleep and activity) and a continuous glucose monitor (to measure blood sugar levels after meals), which is better than most studies that are based only on questionnaires.
Another challenge for future studies will be determining how and why sleeping longer and sleeping later than that person’s typical norm increases morning alertness, at least in this study. We know from other research that oversleeping can also impact well-being.
Improvements in sleep quality impact many other areas of our lives, not least the safety of those in jobs where mistakes can be fatal, including firefighters, nurses and airplane pilots.
“This question is scientifically elementary but also of social relevance, considering that the inability to maintain alertness during the day is an important causal factor in road traffic and occupational accidents, which account for thousands of deaths each year,” the researchers write. .
“Furthermore, insufficient sleep leading to reduced daytime alertness is estimated to be responsible for significant work-related productivity loss, increased health care utilization, and absenteeism from work.”
The research was published in Nature communications.