That’s it. The eight-word title of this article has delivered all the advice you need to live a long and healthy life. We’ve killed or tamed our natural predators, knocked out most infectious diseases with antibiotics, and know enough to keep water supplies clean. What we suffer from now are ailments caused by sitting instead of walking, eating the wrong stuff and abusing our “old friends, the hundred-trillion microbes that constitute our “hidden organ” and account for 90 percent of our bodies. The tricky thing about good advice, of course, is not just admiring it from afar, but taking it out on a few dates with the intent of making a life-long commitment.
Back in the day — 2003 that is — scientists finally figured out the entire human genome and quickly embarrassed everyone. H. sapiens, the smart ape who built cities, wrote novels and conquered worlds had a blueprint of only 21,000-genes: about the same as a worm and half as many as a rice plant. Other clever scientists were busy discovering that our hidden organ of microbes— most of them in our gut — were contributing 4.4 million more genes to our repertoire of basic tools. Many times, because of our diet, lifestyle and overuse of antibiotics in personal health and agriculture, we abuse those tiny old friends that have been with us since the very beginning.
Science is just now really appreciating our superorganism status. (See “Keep your body a healthy habitat for microbial buddies” in the March 2011 North Forty News.) Medical doctors (and their patients) will have to become ecologists, treating individual bodies like complex rainforests filled with creatures that need to cooperate to maintain a healthy habitat. Biologist Alanna Collen provides an excellent summary in her book, “10% Human” (HarperCollins, 2015).
The doctors at the Mayo Clinic say exercise controls weight, combats high blood pressure, diabetes, heart problems and a host of other health issues, improves mood, boosts energy, promotes better sleep, cranks up ones sex life, and just makes you feel better. Even 30 minutes a day will accomplish wonders. Gym memberships not needed. Walk instead of drive, when you can; take stairs instead of elevators. Our hairless bodies and sweat glands support the fact that we started out as endurance predators that walked or ran our prey to death. Our bodies function best when we use them.
Various diets fall in and out of favor, but one would be hard-pressed to find any nutritionist that didn’t say, “Eat more fiber.” Humans spent most of their history hunting and gathering, consuming many more plants than harder-to-come-by animals. Fruits, vegetables and nuts provide most of the fiber we need. Because of the pace of our modern lives, “often a lack of time leads to a lack of fiber,” according to Collen. We buy processed foods because they are cheap and convenient. “For a culture so focused on food, we put very little effort into eating,” she adds.
Care for old friends
One of the greatest lessons I’ve learned as a biologist is that living things do as much or more collaborating as competing. That’s especially true when it comes to our microbe partners. We now know that approximately 4,000 different species share our bodies with us performing all manner of services like making vitamins, digesting food and absorbing nutrients, protecting us from other microbes that would do us harm, and even playing a role in maintaining hormone balance and proper brain chemistry. We—and all other complex animals and plants, for that matter—are microbe high-rise communes with affinities that stretch back a half a billion years. These truly are OLD friends.
Interestingly, these old friends vary somewhat from individual to individual. For example, some weight problems are not entirely because one person eats more than another. Thin people often have a different suite of microbes than obese people — partly as a result of what they eat, but partly gifts from Mom and the relatives. More on that in a moment.
As a young biologist, Collen became infected with a tick-borne tropical disease that threatened to destroy her life. She suffered debilitating symptoms that put her life on hold for long stretches until several rounds of antibiotic treatments seemed to do the trick. But these treatments left behind digestive disorders, allergic responses, and even mood swings that she came to realize were symptomatic of her disrupted microbiome. She began to do the research that led her to realize many of our modern ailments may be tied to abusing our hidden organ: our microbial comrades.
“Our relationship with our microbes is threatened by three things: our use of antibiotics, the lack of fiber in our diets, and shifts in the way we seed & nurture our babies’ microbiotas,” she says
Antibiotics were crucial in conquering infectious disease. Pneumonia, tuberculosis, infectious diarrhea and other diseases caused by bacteria kept average human lifespans at 47 as late as 1900. But we overused them. Broad-spectrum antibiotics kill both good and bad microbes. Antibiotics have no effect on viruses, but patients often demand something when they feel bad and doctors are prone to be better safe than sorry when they are not sure of what’s causing an illness. The result of all this is that strains of bacteria evolve that are resistant to antibiotics. As one antibiotic bullet becomes ineffective we turn to others, but the number of bullets at our disposal has decreased alarmingly. Meanwhile, some of those bullets are killing our old friends.
With the success of penicillin and other antibiotics beginning in the 1940s, ranchers quickly found that livestock grew fatter on antibiotics, resulting in greater profits. The precise link between antibiotics and increasing weight is not known, but it shouldn’t have been too great a shock when people started to pork up. We are animals, too. Indiscriminate use of antibiotics disrupts microbial helpers and leads to various forms of inflammation—inflammation that may have connections to many modern ailments, including autism, eczema, allergies, multiple sclerosis, rheumatoid arthritis and lupus.
Mom gives us our first gift at the moment of birth. Our first collections of old friends hitch rides with us as we travel down the birth canal. We drink our second gift: mother’s milk full of more old friends and the unique blend of nutrients specific to our kind. More and more women, especially in some urban areas, elect to give birth by C-section. Many of these elective surgeries are for convenience only. While some C-sections are life-saving necessities, others may just be depriving children of a much-needed organ for survival.
In a similar vein, some women need help and assistance when it comes to providing enough mother’s milk, but using formula for convenience or weaning babies too soon can do great disservices to that child.
Knowledge really is power and Collen’s book provides great advice for anyone growing up in the brave new world of the 21st century. “As an adult,” she says, “the food you eat and the medicine you take determine the microbes you have. Treat them well and they will return the favor.”