Is Mahjong Good for Your Brain? What the Research Shows

I don't usually write about board games. Somebody asked me a simple question — is mahjong good for seniors — and I figured I would spend twenty minutes on it and move on.

Two hours later I was still reading. It turns out researchers have been studying this game seriously for years, and not just by watching people play. Some of them ran proper trials.

The Evidence

Somebody went and gathered up everything that had been published on mahjong and older people — 53 studies in all, across thirteen databases in the West and in Asia. That is the 2024 review I keep coming back to. Most of those 53 just watched people who already played. Six actually ran an experiment.

The watching studies all pointed the same direction. The more mahjong someone had under their belt, the better they tended to do on thinking, on mood, and on getting through daily life. The experiments were the interesting ones, though, because there the researchers put people at the table who would not otherwise have been there. Those found gains in general thinking and short-term memory, and less depression.

The one I would point anybody to is a 2020 trial. They took 56 people who already had measurable memory trouble and flipped a coin. Half sat down to mahjong three times a week for twelve weeks. Half carried on with their lives as usual.

At the end, the mahjong half had improved at the kind of thinking I worry most about losing — planning something out, making a decision, holding a complicated task together in your head. The other half had not improved at all.

Three months. Three afternoons a week. In people whose decline had already started. Nothing to swallow, nothing to buy, nothing to go wrong.

The finding I care about most: researchers followed 676 older adults and looked at two habits side by side — playing mahjong, and getting regular exercise. People who had played mahjong for years were roughly 40% less likely to have mild cognitive impairment. People who exercised regularly were about the same, also roughly 40% less likely.

But the people doing both did better than either habit alone would predict. The two did not just add up. They multiplied.

This is observational data, so it cannot prove the games caused the difference — sharper people may simply be more likely to keep playing. But the pattern held after the researchers accounted for the obvious explanations.

That's the stacking principle again, and it's the most useful thing in this literature.

On mood: a widely cited 2019 study in Social Science & Medicine analyzed 10,988 adults 45+. Among urban participants, playing mahjong predicted a significant decline in depressive symptoms.

The Caveats, Because They’re Real

Nearly all this research is in Chinese and Hong Kong populations. Mahjong there isn't just a game — it's a social institution with its own etiquette, regular groups, place in family life. Study mahjong in that context and you're studying a whole bundle at once. A Westerner learning from an app isn't getting the same intervention.

Reverse causation is a serious problem in the observational data. People whose cognition is declining stop playing complex games. That alone would produce the association with no benefit from mahjong whatsoever. The trials help, but 56 people over 12 weeks is small.

And effect sizes are modest. Nobody reversed dementia. Improvement on cognitive scales and slower decline. Real, worth having, not miraculous.

What’s Actually Going On

Mahjong is probably not special. What it is, is a delivery vehicle for four things at once:

Working memory load — tracking discards, holding a strategy, updating as the table changes
Pattern recognition under time pressure
Sustained attention — an hour without drifting
Face-to-face social engagement, with the same people, on a schedule

That fourth one is doing more work than the first three combined.

Consider the contrast. Solo brain-training apps have a famously weak record — you get better at the app and it doesn't transfer. Cognitively demanding activities done WITH OTHER PEOPLE, REGULARLY keep producing benefits study after study.

The qualitative research backs this up. When researchers asked older players what the game did for them, they didn't talk about memory scores. They described self-esteem, competence, eased worries, real social support. One study found it gave them a sense of youthfulness.

That's not a cognitive mechanism. That's a human one.

What to Actually Do

If mahjong appeals, play it. If not, don't force it — get the ingredients elsewhere:

Bridge, chess club, poker night, dominoes, a serious board game group. Same four ingredients.
In person beats online. The social component isn’t decoration, it’s most of the effect.
Standing schedule beats occasional. “We play Thursdays” is an intervention. “We should play sometime” is not.
Same people beats strangers. The relationship accumulates.
Stack it with movement. Walk to the game. Play, then walk. Cheapest upgrade available.

Avoid: assuming a brain-training subscription substitutes. That's the thing this research most clearly does NOT support.

Why I Take This Seriously at 71

I spend thousands of dollars chasing 200 — supplements, bloodwork, wearables, protocols. Every dollar of it is on my site for anyone to see.

Then along comes this. A trial behind it. No cost at all. Nothing to swallow and nothing that can go wrong. And it moves the exact kind of thinking I am most afraid of losing. The only thing standing between me and it is putting a night on the calendar and rounding up three other people.

That is an embarrassing deal compared to most of what I pay for. It is also exactly the sort of thing everybody skips, mine included, because nobody sells it and there is no bottle to put on the counter.

Social connection keeps turning up in longevity research as a first-tier variable. A weekly game night isn't a cute lifestyle suggestion. On the evidence, it's a protocol.

BOTTOM LINE: it's not the tiles. It's the challenge, the people, and the recurring appointment. Get those three however you like.

Want to see the rest of what I do? Here is my full protocol list, my fitness routine, and every biomarker I track.

Stay sovereign, stay healthy,

Gary

A note from Gary: I am not a doctor, and I am definitely not your doctor. I am a 71-year-old running a 129-year experiment on myself and publishing the results as they come. Talk to your physician before changing anything about your own health.

Applications Are Open

The 200 Year Life Mastermind

If you would rather do this alongside other people than alone, I am opening a small group. One year, live on Zoom, working through the protocols together.

See the Details →