Are Young Adults the Loneliest Age Group, or the Least?

Gallup’s 2023 survey of 142 countries found that adults aged 19 to 29 report the highest rate of loneliness of any age group, 27%, against 17% among people 65 and older. Harvard’s Making Caring Common project, surveying Americans in early 2021, found something that looks similar on its face but is not the same claim: 61% of young adults aged 18 to 25 reported serious loneliness, more than any other age group in that survey too. Both studies agree on the ranking. They disagree, by a factor of more than two, on the size of the problem. That gap is worth taking apart rather than averaging away.

Same conclusion, different instrument

The Gallup figure comes from a single-item measure: respondents were asked how much of the previous day they felt lonely, and 24% worldwide said “a lot” or “quite a bit.” The Harvard figure comes from a different construction entirely, combining several loneliness and isolation indicators into a composite “serious loneliness” measure, fielded during the acute phase of the COVID-19 pandemic in the United States alone. One asks about yesterday. The other asks about a general state, aggregated across several questions, at a moment when in-person contact had been curtailed for the better part of a year.

This is not a minor technical footnote. The state of loneliness research, as a 2023 review in BMC Public Health documented, is hampered precisely by this kind of instrument inconsistency: different studies use different scales, different reference periods, and different thresholds for what counts as “lonely,” which makes prevalence figures very hard to compare across sources even when they are nominally measuring the same thing. Gallup’s day-level question and Harvard’s composite trait-level measure were never going to produce the same number. The interesting finding is not that they differ. It is that they agree on the direction of the age gradient despite differing so much on magnitude, and that both differ sharply from a third data point: the AARP Foundation’s 2018 survey of adults 45 and older, using the 20-item UCLA Loneliness Scale, found one in three lonely — a figure sitting between the other two, from yet another instrument, on yet another population.

The pandemic year is doing work here too

Publication date matters as much as instrument here. The Harvard report was published in February 2021, describing data collected as the pandemic’s first winter was ending, when university closures, remote work, and restricted gathering had disproportionately affected people in the age range most likely to be starting careers, forming new social ties, or living through the kind of transition that depends on physical proximity. Gallup’s figures were fielded between June 2022 and February 2023, well past the most acute disruptions, in a design spanning 142 countries rather than one. A 27% rate for young adults measured in 2023 and a 61% rate measured in the first pandemic winter are not necessarily describing a stable trait of the age group so much as two different moments in a volatile period, sampled at different points on the recovery curve.

The Cigna Group’s 2025 report on loneliness in America, drawing on fieldwork from mid-2024, offers a check on whether the young-adult gap persisted once the acute pandemic period had passed. It found 57% of Americans overall reporting loneliness, with Gen Z and Millennials reporting more than Gen X and Baby Boomers, despite greater technological connectedness. That is closer to Harvard’s elevated picture than to Gallup’s, though again using its own methodology and again a single-country sample. The persistence of the ranking, across a single-item global measure, a pandemic-era composite, and a 2024 U.S. survey, is the most defensible finding here. The precise size of the gap is not.

What the disagreement should not obscure

It would be a mistake to treat the discrepancy as evidence that the underlying pattern is unreliable. Gallup’s own later work, a 2024 release finding that more than one in five adults worldwide feel lonely a lot of the previous day, again showed elevated rates concentrated among younger respondents. Three independent survey operations, three different instruments, three different years, and the age gradient holds each time even as the absolute numbers move by tens of percentage points. That is a stronger form of evidence than any single number, because it is not contingent on one wording choice.

What it cannot do is tell a policymaker or a journalist which number to cite as “the” youth loneliness rate, because there is no single number. Reporting that young adults are lonelier than older adults is on solid ground. Reporting that the rate is 27%, or 61%, or 57% requires naming the instrument, the year the data was collected, and the population sampled, because none of those figures is more authentic than the others; they are answers to different questions that happen to share a label.

A study designed to resolve this would need to run the same instrument, at the same reference period, across the same age bands, longitudinally, in more than one country — precisely the design none of the existing loneliness surveys share with one another. Until that exists, the honest summary is narrower than any single headline figure: young adults report more loneliness than older adults, consistently, and by an amount that current instruments cannot pin down.