174 Achieving pH Balance to Treat Specific Ailments
A Brief History of Sleep
While the various systems inside our bodies speed up and slow down
in tandem with night and day, we have not synchronized our waking
and sleeping patterns with any such exactness. In the seventeenth cen-
tury, before the electric lightbulb was invented, and even before the use
of oil and gas lamps, people went through alternating periods of sleep
and wakefulness at night. While they went to sleep as soon as it got
dark, they awakened periodically during the night. During the time
they were awake they meditated, chatted with their bedfellows—since
before the twentieth century families typically shared the same bed—
visited neighbors, or worked by candlelight.^1 This was such a widely
established pattern that people commonly referred to their fi rst and
second sleep. Thomas A. Wehr of the National Institute of Mental
Health did a research study that showed that when subjects were
deprived of artifi cial light they reverted to the preindustrial sleeping
mode and were asleep and awake in turns during the night. Wehr
believes this adaptation occurred because, without artifi cial light, pro-
lactin hormone levels, which bring about “a state of quiet restfulness,”
were raised.
Thus even when the only means of lighting up the darkness was the
candle, people were defying the pineal gland’s orders—delivered by its
messenger melatonin—to sleep while it was dark and not wake up until
the fi rst sign of sunlight. People viewed wakefulness at night as entirely
natural. Roger Williams, professor of biochemistry at the University of
Texas in the mid- to late twentieth century, told me that waking up at
night shouldn’t be labeled insomnia or considered unhealthy if sleep
that was lost at night was made up during the day.
In Spain and Greece people commonly sleep two hours every after-
noon and then stay up very late at night. When I was staying at a hotel
in Madrid, I was awakened at 4:00 a.m. by people talking on the street.
Yet in the daytime the streets in this major metropolitan city were
empty. In these Mediterranean countries people don’t observe the day-
night cycle because when the sun is directly overhead the heat is so
intense it saps the body of energ y, mak ing it almost impossible to work.
For the same reason, Middle Easterners who live in the desert turn the
daily cycle of light and darkness upside down by sleeping in the daytime