Studies that focus on a single person — known as N-of-1 trials — will be a crucial part of the mix. Physicians have long done these in an ad hoc way. For instance, a doctor may prescribe one drug for hypertension and monitor its effect on a person’s blood pressure before trying a different one. But few clinicians or researchers have formalized this approach into well-designed trials — usually just a handful of measurements are taken, and only during treatment.
First, there is a growing interest in ‘omics’ assays that expose people’s unique characteristics at the molecular level. Researchers and clinicians are assaying people’s blood metabolites (their metabolome) and the microbes in their bodies (their microbiome) as well as their DNA and RNA9. Second, cheap and efficient devices that collect health data are becoming available, such as the Apple Watch, continuous glucose monitors and portable electroencephalogram (EEG) monitors. Lastly, governments and life-sciences funding bodies worldwide are increasingly supporting a more targeted approach as well as patient engagement in medicine, such as through the US Patient-Centered Outcomes Research Institute, established in 2010.
This article primarily focuses on one-person trials in the context of drug research. Personally, I think they have just as much potential in nutrition research as well; after all, while generic dietary guidelines can be effective, the only way to truly optimize health is through individualized research and trial-and-error. These studies have been done before, which is why it’s silly to dismiss something simply because it goes against conventional wisdom—if it’s worked for one person, it can work for many.