Researchers found that there is no point where higher IQ ceases to be beneficial. Any thresholds found were trivial importance (ΔR-sq < .01) and did not replicate across samples.
This study examined the persistent debate about the importance of cognitive ability for life outcomes, specifically addressing the idea that high cognitive ability (above IQ 100 or 120) is either irrelevant or harmful. Analyzing data from four large longitudinal studies in the US and UK, researchers found a strong positive correlation between cognitive ability in youth and later success in education, occupation, health, and social aspects of life.
They found no indicator supporting the idea of a threshold beyond which higher cognitive ability ceases to be beneficial.
This means that higher cognitive ability is almost always advantageous then.
It makes me think though… Why do you think this belief of high cognitive ability having detrimental effects still persists despite evidences against it?
And if cognitive ability is so important, are there possible interventions applicable for everyone that we can do to enhance it?
The “too smart” myth probably persists because of survivorship bias and stereotypes. We notice the socially awkward genius more than the 50 well-adjusted high-IQ people. Also makes average folks feel better to think “at least I’m not TOO smart.” This study with 48k+ participants across decades is pretty definitive though - more IQ = better outcomes, period.
@J-I exactly. Pop culture loves the “tortured genius” trope.
For interventions - early childhood nutrition, quality education, reducing lead exposure all help. But honestly most IQ variance is genetic (50-80% heritable by adulthood). Environmental interventions have diminishing returns after childhood. The Flynn effect shows population-level gains are possible though.
But doesn’t this just justify inequality? If smarter = better outcomes and IQ is mostly genetic, aren’t we saying some people are just destined to succeed more?
@JuliaB what about emotional intelligence or grit? Those matter too right?
@M.Evanta Grit correlates with IQ and adds little predictive power after controlling for it. EQ is controversial - most measures overlap with personality traits. Study isn’t saying destiny, just that IQ predicts outcomes. Policy should focus on what we CAN change.
If we kill the “too smart” myth with this data, gifted programs stop looking like charity for misfits and start looking like public-health investments. High-IQ kids already self-select into better trajectories; accelerating that with early enrichment could compound societal returns.
A 2017 meta-analysis found that grit’s incremental validity over and above conscientiousness was questionable. Other research found that when accounting for genetic and personality factors, grit added little predictive power for academic achievement.
I don’t know, I’ve met plenty of really smart people who overthink everything and can’t function in normal social situations. Maybe the study didn’t measure the right things.
I’d caution against dismissing people’s lived experiences as just “stereotypes.” While the study measures objective outcomes like income and education, it doesn’t capture subjective well-being or the psychological costs some high-ability individuals face (existential distress, social isolation, or the burden of unmet potential). We should be careful not to use population-level data to invalidate individual struggles or assume that career success equals life satisfaction.
Yes, cognitive ability is partly heritable and predicts outcomes, but that doesn’t make our current distribution of resources or opportunities morally right. The question isn’t whether intelligence matters (it does), but whether we want to live in a society that only rewards cognitive ability while leaving everyone else behind. We can acknowledge the correlation while still fighting for systems that provide education, healthcare, meaningful work, and dignity regardless of where someone falls on the ability spectrum.
The idea that there is a certain IQ point at which being smarter is not beneficial is called the “threshold hypothesis.” It’s hard to say that it’s been disproven completely because it’s hard to test every possible threshold for every possible outcome. But every credible test of the threshold hypothesis has come up empty. It seems likely that either (1) it is false, or (2) thresholds are so high (probably IQ of >160) that they would only impact a miniscule number of people.
