Two papers in a week priced the fundamentals in years. Here is the receipt.

Two large studies from a University of Sydney team landed this week, and together they are the closest thing we have to a price list for the fundamentals. The first, in eClinicalMedicine, followed 59,078 UK Biobank participants, median age 64, for about eight years, with sleep and activity measured by wrist devices rather than questionnaires. People in the most favorable third for sleep, movement and diet together had about 9.4 more years of life, and about 9.5 more years free of major disease, than people in the least favorable third. The second, in The Lancet, pooled device-measured activity from 135,046 adults in Norway, Sweden, the United States and the United Kingdom and asked a population question: if everyone except the most active added five minutes a day of moderate activity, how many deaths would be averted? Up to 10%.

The number that will be misread. The eClinicalMedicine paper estimated the smallest combined change associated with a year of extra life: about five more minutes of sleep, two more minutes of moderate activity and a modest diet improvement — half a serving of vegetables — a day. The point estimate is 0.92 years, with a range of 0.69 to 1.15. The Lancet figure is a population attributable fraction, not a personal discount: it describes deaths averted across a whole society if everyone moved, and the lead author was careful to say that small changes help a population and may not help any particular person. Both are observational. Both authors list the usual limits — reverse causation, self-reported diet, a cohort healthier than the country it came from. And one senior author discloses equity in a company that promotes physical activity, which we note because we would note it for anyone.

Loree’s take

What I take to the office is the shape, not the decimal. The biggest gap in the data is between the people doing the least and the people doing a little, and the three fundamentals moved together did more than any one alone — the paper found diet by itself did not significantly change lifespan, and sleep alone would have needed a 60% increase to buy the same year. Nobody has to optimize anything. They have to sleep a little more, move a little more and eat a little better in the same week.

Ben’s take

Notice what is not in either paper: a product. No supplement, no device, no panel, no protocol. The interventions that bought nine years in the first study are free, and the five minutes in the second study cost nothing. This is the evidence base the longevity industry sells around, and these two papers are what it looks like when it is measured with devices in 190,000 people. Keep the receipt.

Why it matters to a recovering optimizer. The book we are writing rests on an argument these papers make with better data than we had: the overwhelming share of the benefit comes from the fundamentals, done modestly and together, and the transition from sedentary to slightly active is where the years are. If you have been waiting for proof that small is enough, this is the week it arrived — with the honest caveat that it is association, measured well.