Our bodies depend on a regular cycle of movement and rest called a circadian rhythm. It’s a biological dependency on spans of light and dark. When the earth is in sunlight, our brains force us to be active. At night, we are compelled to slow down. If we interfere with this biological clock, we may become more prone to illness and even reduce our life expectancy.
This same need for regular movement and rest can be found in our microbial population, particularly species found in the gut. Bacteria do not sleep, but they do rest. Inside us, they tend to follow a schedule similar to ours. They spend the daytime hours eating, metabolizing, and multiplying, and during the night they become less active and focus on maintenance, including repair and detoxification. This change can be seen in the numbers of each type present. During the daytime, some species, like the lactic-acid bacteria, can increase as much as 15 percent over amounts seen at night. They multiply quickly when being fed during daylight hours, and die nearly as quickly in the absence of nutrients during sleep.
Bacteria tell the time by the presence of nutrients, such as those provided by our own meals. When we eat, they know it’s time for action. Between our meals, they can relax. The alignment of rhythms not only keeps our bacteria happy but also improves our overall metabolism, helping us to stay in shape.
If we maintain our three square meals and get seven to eight hours of sleep at night, the bacteria work alongside us to keep everything balanced and calm. But if a person messes with the rhythm, it means trouble for the microbes. The species needing that regular nutrient/starvation rhythm begin to suffer. A blip in the rhythm is akin to a massive shift in their environment, and confusion sets in. They seem unable to synchronize. A once-friendly home is seemingly no longer hospitable. This is when that 15 percent change really takes effect. The bacteria that are switched on will overgrow and become too populous, while those that are switched off will decrease in number significantly and may disappear altogether. The result is a loss of diversity, known as dysbiosis.
In the sleepless, dysbiosis can bring about a change in metabolism. The body can use only so many nutrients in food; the rest have to be broken down by the bacteria in the gut. Without them, we lose out on the potential for balanced sugar levels and efficient fat burning. We feel lethargic and may put on weight. Over time, we may develop mood disorders, lowered brain function, diabetes, or cardiovascular disease.
The way to reverse this trend is simply to get more sleep. If for whatever reason that’s not possible, you can still trick your gut bacteria into thinking everything is going well. You do this by dividing your usual food intake over the course of a day and spread it out into more meals during both day and night hours. This cycle of feeding and starvation will balance the numbers of bacteria. This allows you to travel and enjoy the sights while keeping your gut believing everything is copacetic.