In addition to learning more about his own biology, Snyder thinks it offers a new way of tracking health measures and eventually might replace getting blood drawn at the local doctor’s office.

Such micro-sampling, he said, is convenient, can be done more frequently than an annual or semi-annual blood draw, and doesn’t require visiting a clinic with sick people.

“I think it’s going to take over the way we do health monitoring,” Snyder said.

Dr Eric Topol, founder and director of the Scripps Research Translational Institute, who is not involved in the work, said the sampling was interesting, but not yet ready for widespread use.

“It’s an unprecedented depth of data collection,” Topol said. “Whether that’s useful is another question.”

How Snyder’s approach differs from Theranos’

“It’s Theranos that works,” Snyder said of his own technology.

Theranos also used a drop of blood, but in Snyder’s approach, blood is shipped to a conventional lab that sorts molecules based on their mass and electronic charge, while Theranos promised a new analytical process that never worked.

Other companies are currently developing blood tests based on a single drop, but Snyder envisions his being conducted more regularly at home, rather than during an occasional doctor’s visit.

What the study found

Snyder and his colleagues examined a broad range of factors from each sample, including those involved in metabolism, the immune system, blood sugar and other health measures.

In his own samples, he was able to see how his body metabolises aspirin and how long it takes for his glucose to spike after eating, which is useful for someone like him with diabetes.

“Now I have a little less and try to stop earlier,” he said, though he’s not sure whether it’s making a difference.

Others processed the shake more slowly and in some, markers of inflammation fell, suggesting it provided a benefit.

Knowing what foods cause or reduce inflammation “would be very, very powerful”, Snyder said, helping people make more personalised decisions about which foods to eat or avoid.

What are the challenges?

But computer technology can’t yet thoroughly analyse such a complex set of data collected repeatedly, Topol said, and not everyone will want to draw their own blood or mail it in.

“This is alluring,” Topol said, but “this is very involved for the person. It’s expensive. These practical issues are going to have to be validated that it’s worthwhile.”

What’s the potential for this kind of blood work?

“This technology provides a feasible way to collect rich molecular information in people’s daily life using easily accessible finger prick blood draw,” Gao said.

Snyder said this approach could eventually be used to track stress, watch for early signals of disease and see which foods are problematic for which people.

He and his team have already begun tracking patients with chronic fatigue syndrome, also called myalgic encephalomyelitis, to see what triggers their bouts of exhaustion and identify signs of an impending crash.

They are also getting ready to launch a study looking at how the “exposome” – the pollution, chemicals, bacteria, pollen and mould in the environment – affect someone’s blood chemistry.

“I could see nearly all blood tests being run from the (person’s) house in the future,” Snyder said. “It just makes sense.”