Biohackers think you can program the body like a computer. They’re wrong

It’s easy to feel as though you’re doing something wrong these days if you don’t know your VO₂-Max and how many hours of REM sleep you get each night, or if you’re not taking a dozen different supplements and scrutinizing every morsel of food that makes its way into your mouth. “Biohackers” and other longevity seekers — with their many podcasts, YouTube channels, and X accounts — would have you believe that if you diligently measure your every bodily function and meticulously tailor your nutrition and exercise regimens, you can reprogram your body to live longer and evade dreaded diseases, just as a computer can be programmed to perform virtually any desired task.

As a doctor, I hear these bold claims and worry that my patients will feel they have somehow failed if they develop a serious disease. As a biotechnology executive, I have a healthy respect for the power of biology — and our inability to control it precisely.

These folks’ logical flaw is to assume that the biological processes in your body are just as predictable and controllable as transistors on a microchip. What they don’t understand, or choose to ignore, is that the human organism is far too complex and unpredictable for that level of control.

Take, for example, a recent fad among people without diabetes to closely monitor their bodies’ glucose levels. Many longevity seekers advocate for wearing a continuous glucose monitor, a device with a small needle that resides under the skin, constantly measuring the glucose level in the body. (It was originally developed to monitor the glucose levels of people with diabetes.) They claim to use the data generated by these devices to learn how to customize their diet for optimal glucose levels.

The trouble is, our bodies’ glucose response to food intake is far too inconsistent to produce informative results. Researchers in a recent study fed participants identical meals separated by one week in a highly controlled hospital environment, while the participants wore continuous glucose monitors. Even when eating identical meals under these artificial conditions, the glucose measurements from a given participant looked no more similar than when the participants each ate an entirely different meal. A scatterplot the researchers made comparing the glucose results from one meal against the identical meal a week later looked like it could have been made by a person throwing darts blindfolded.

Randomness is inherent to life. Our parents’ chromosomes are shuffled like a deck of cards before we receive half of each of their genetic code. Our body’s immunity against disease through antibodies is the product of a random sorting process called V(D)J recombination, where our white blood cells produce billions of different antibodies, hoping that they will target the right pathogen. Some of them do, most do not, and occasionally they target our own body instead, creating autoimmunity.

              Diseases are often the result of random processes. In the case of cancer, there are certain behaviors we control that do predispose to cancer-causing mutations, such as smoking or exposure to ultraviolet light. More than two-thirds of cancer-causing mutations, however, are not due to anything we’ve put our bodies through. They are the unavoidable result of random errors introduced in our DNA by the molecular machines that copy our DNA before our cells divide. No matter your exercise routine or diet, you cannot prevent these random mutations.

After the inciting mutations occur, our immune system can still save the day by finding the cancerous cells and destroying them. Again, this process is influenced by chance. If the right white blood cell to identify a cancer cell happens to be in the vicinity of the mutant cells, it can find the cells and eliminate them before the cancer becomes detectable. If those white blood cells are not in the area, the cancer cells can proliferate. Lifestyle choices only have limited impact on this layer of protection.

Luck plays a key role in other diseases as well. We all became familiar with the arbitrary way that Covid-19 infections spread throughout a group, infecting some people who are exposed and inexplicably sparing others — even, in some cases, those who seem more vulnerable to infection. More viral particles might happen to drift in the air toward one person and away from another, and some people may have better immunity against infection for reasons that are still not well-understood.

If a blood clot forms in the left side of the heart, it can float out of the heart and into the large arteries in the chest. If the clot takes a turn and makes its way into the carotid arteries, it can cause a devastating stroke. If, on the other hand, the clot travels downward away from the head, it will often cause less severe damage and could go entirely undetected.

Implicit in the biohacking movement is the belief that if only one could diligently optimize all bodily inputs, one could avoid deadly diseases like cancer. But the prominent role played by chance in our health outcomes should remind us that disease can affect anyone. In my practice, I see too many patients who blame themselves for their conditions. They wonder if they ate the wrong foods, didn’t exercise enough, or were exposed to some harmful toxins earlier in life. While all of these factors can cause disease, they should also consider the very real possibility that there may not have been anything they could have done to avoid their condition. They might simply have drawn the short biological straw.

There is a growing industry of people and companies selling biohacking advice, tracking devices, and supplements. They believe they are selling people hope for better health. In reality, they may be selling people guilt that they haven’t done more already to control their health and may create a burden of unachievable expectations.

Of course, none of this is meant to imply that there is nothing we can do to affect our health. Basic health maxims still apply: Don’t smoke. Don’t drink excessive amounts of alcohol. If you’re obese, lose some weight. Control your blood pressure and cholesterol.  Exercise. Get age-appropriate vaccinations and cancer screens.

But obsessing over minute-to-minute changes in your glucose level or tracking your blood levels of a dozen different vitamins and minerals is unlikely to make a massive impact on your health. If you get pleasure out of tracking all of these details, I might question your choice of hobby, but I won’t try to talk you out of it. But if you’re doing these things because you believe you can exert complete control over your health outcomes like a programmer writing a piece of code, my message is: Don’t sweat the small stuff.

Alex Harding, M.D., is an internal medicine physician at Massachusetts General Hospital in Boston and an entrepreneur-in-residence at Atlas Venture, a life science venture capital firm in Cambridge, Massachusetts.