As the sun begins its dip into early evening darkness these Fall days, our mood and mental energy seem to dip with them. Known as the afternoon slump, or the brain-dead zone, most of us feel an urge to be in bed with a pillow over our heads rather than continuing on with our work obligations for another few hours.
Indeed, the fatigue sometimes seems so overwhelming, especially when the work preceding late afternoon has been so mentally and emotionally stressful, that our bodies feel as if they have been on a construction site all day. A friend who is a litigator told me that two days of yard and house chores over a weekend do not leave him nearly as tired as doing a cross examination in a courtroom; even though his physical activity is limited to standing, sitting, and occasionally walking a few feet from his chair to a table. “There is something peculiar about late afternoon,” he told me. “I consider myself a pretty calm guy and able to resist reacting to insults or challenges from other lawyers or a judge. But around 4PM, I feel myself either feeling suddenly sensitive to the tension in the courtroom, or overcome with profound fatigue. ”
A late afternoon slump can descend on anyone—a UPS delivery person, a daycare assistant, or a neurosurgeon. And it is more likely to occur as the days shorten and the light outside no longer feels like noontime, but more like the start of evening.
The Internet and magazine columns are full of advice about this problem, most of it entirely wrong. Many advice givers assume that the slump is caused by the body’s need for energy, and recommend eating a bigger lunch and/or snacking to increase low blood sugar. But the cause of the fatigue and mood changes resides in the brain, not in the blood. Is anyone really famished at four in the afternoon? If someone exercises at lunch but doesn’t eat afterward, he or she will be quite hungry by late afternoon. But the rest of us? Most of us beyond infancy do not need to be fed every three or so hours, and if lunch is over at one o’clock, our bodies really do not have to be fed again three hours later. But our brains are something different.
To understand what lies behind the need to nap, rather than write a report in the late afternoon, we have to see what is going on with serotonin, that brain chemical which attempts to keep us energetic, in good humor, and focused.
It seems that something happens late in the afternoon to the activity of serotonin. There may not be enough of this neurotransmitter, or its activity may be slowing down; whatever the mechanism, the result is a deadening of mood, motivation and mobility.
We discovered this en route to studying something else; i.e., why many people wanted to eat a sweet or starchy carbohydrate snack late in the afternoon. The backstory is that these volunteers were living in a research residence where snacks where available 24/7. But they never snacked until late afternoon. Why then? They told us they felt their mood deteriorating at that time. They felt depressed, tense, impatient, and tired. They could not concentrate either. And they claimed that after they ate the carbohydrate, they felt better.
All this was anecdotal, interesting, but not scientifically valid. We wanted to know: Did they really feel better after eating carbohydrate or just thought they did because they liked to snack?
They really felt better. We gave them a drink that contained enough carbohydrate to increase the production of serotonin in the brain (serotonin is made only after carbohydrates are eaten, not protein) and at another time, a drink that did not increase serotonin (it contained protein).
Their moods including fatigue were tested before the drinks and about an hour or so later. They did improve their moods, and were less tired after the carbohydrate drink, but not after the drink containing protein.
So the volunteers taught us something very useful: if you want to lift yourself out of a slump (this does not apply to baseball) eat a carbohydrate snack.
Two suggestions to lift late afternoon mental and emotional fog: eat 25 grams of a starchy carbohydrate such as pretzels, popcorn, graham crackers, or a piece of bread. (Carbohydrate avoiders will have to stay in their fog). Avoid any starchy food with fat, which will make you feel lethargic and dull. Don’t eat fruit! No serotonin is made after eating fructose!
And, move. Vigorously. Wait until you swallow your snack, then get up from your chair and do something physical. Find a staircase and climb it a few times. Take 10 minutes to jog around the block. (Remove high heels before you do this.) If you are home, find a jump rope, set the egg timer and jump for 3 minutes. Or if you have a treadmill or bike, run or pedal for 5 minutes until your heart rate goes up.
Your brain will thank you. Now go back to work.
Or take this to work and as a reminder.