Extra cash for families slowed a DNA aging score in their kids, trial finds

Do cash transfers slow aging in children? A large trial in the United States has a first, small answer. Scientists gave 1,000 mothers with low incomes either 333 or 20 US dollars a month, starting just after their baby was born. When the children turned 4, the team tested their saliva [1].

Kids in the 333 dollar families scored as aging a little slower on a DNA test. The gap was about a sixth of the normal spread between children, which is small. The mothers' own scores did not change [1].

One plain caveat comes first. This is a score from a DNA test, not a health check, and nobody knows yet if the change lasts or matters for health later on [1].

The work was led by Laurel Raffington of the Max Planck Institute for Human Development in Germany and published in Nature Human Behaviour in 2026. It was funded by the US National Institutes of Health, the Jacobs Foundation and the Max Planck Society, among others. The authors say they have no competing interests [1].

How did the cash trial work?

The trial is called Baby's First Years. Mothers were found at 12 hospitals in four areas: New Orleans, Omaha, the Twin Cities and New York City. To take part, a mother's income had to be below the US poverty line [1][3].

Chance decided, like a coin flip, which group each mother joined. 400 got 333 dollars a month and 600 got 20 dollars a month, with no rules on how to spend it. The extra money raised a typical family's income by about a fifth [1][3].

The cash was first planned for just over three years. It was later stretched to the first six years of each child's life, and the last payment went out in September 2025 [1].

The DNA test is called DunedinPACE. Every cell holds DNA, the body's instruction book. Small chemical marks sit on top of it, and their pattern shifts with age. DunedinPACE reads that pattern and guesses how fast a body is aging right now, a bit like a speedometer rather than a clock [1][4].

It was built from a group of adults in Dunedin, New Zealand, followed for twenty years. In adults, a faster score has been linked to more illness and earlier death [4]. Using it on 4 year olds is newer, and the authors say researchers still disagree about what it means in children [1].

What did the study find?

Saliva DNA results were ready for 735 children. On DunedinPACE, kids in the 333 dollar group came out about 0.17 of a standard step slower than kids in the 20 dollar group. A standard step here means the normal spread of scores between children, so 0.17 is a small shift [1].

Two other DNA age tests, called PhenoAge and GrimAge, showed no difference. The team had expected that, since those tests work less well in children. A DNA score linked to thinking skills did not go up with more cash either, though that result was hard to read [1]. The authors summed up the open question this way:

Whether this epigenetic effect persists and how it may relate to behavioural and health outcomes remains unknown.

Raffington and colleagues, Nature Human Behaviour, 2026 [1]

In plain words, nobody knows yet if the slower score will stick, or if it will show up as better health, learning or behaviour. Epigenetic just means the marks that sit on top of DNA [1].

There is one more detail that most short reports leave out. In these same 4 year olds, the DunedinPACE score was not linked to their weight, brain activity or thinking test scores. It was not linked to how healthy their mothers said they were, either [1]. So the score moved, but nothing else measured at age 4 moved with it.

Was this the main goal of the trial?

No. The trial's public registry entry lists children's language, thinking skills, behaviour and brain activity as its main measures. The DNA aging score is listed as a secondary measure, planned for ages 4, 6 and 8 [2]. The team says it was added before the age 4 visit, and its analysis plan was posted before the DNA was read [1].

Earlier results from the same trial were mostly flat. Another paper found that four years of cash did not change the mothers' mental health or anyone's weight. It also did not change how healthy mothers said their children were [5]. By contrast, the DNA score is one of the few measures that moved [1][5].

For scale, an earlier trial in adults who ate a quarter fewer calories for two years also slowed DunedinPACE a little. That trial, called CALERIE, was in healthy adults, not children, and its authors also called the change small [6].

This study does not show that extra cash makes children healthier or helps them live longer. It does not show that the change lasts, since the kids are still young and the test has only been done once. It does show that, in a fair test, more money at home went with a slightly slower DNA aging score in 4 year olds. The 6 and 8 year checks may say whether it holds [1][2].