You can meaningfully improve your measured IQ score — through education, practice and better health — but you cannot dramatically raise your underlying general intelligence as an adult, and anyone promising a 20-point jump is selling something. That's the honest answer, and it's more useful than the hype. The research draws a clear line between general intelligence, which is fairly stable in adulthood, and test performance and specific cognitive skills, which respond well to the right inputs. This guide walks through what actually works, what doesn't, and what realistic improvement looks like.
What's stable and what's trainable
IQ scores are strongly rank-stable in adults: if you score above the average of 100at 30, you'll very likely score above average at 50. That stability reflects general intelligence — the broad ability that IQ tests estimate. But your measured score on any given day is not the same thing. It also reflects how familiar you are with the item formats, how well you slept, how anxious you are, and how much your specific skills — working memory strategies, pattern-recognition habits, vocabulary — have been exercised. The stable part limits how far you can move; the rest is genuinely improvable.
Education: the one proven way to raise IQ
The strongest causal evidence for raising IQ comes from schooling. Ritchie and Tucker-Drob's 2018 meta-analysis in Psychological Science pooled quasi-experimental evidence from over 600,000 people — including natural experiments where laws forced some cohorts to stay in school longer — and found that each additional year of education raises IQ by roughly 1 to 5 points, with effects that persist across the lifespan. This is not selection bias (smart kids staying in school longer); the designs specifically isolate the causal direction. Education seems to work by building exactly the skills tests sample: abstract reasoning, verbal knowledge, sustained concentration. For adults, the practical translation is that structured, effortful learning — a demanding course, a new technical skill, a language — is the closest thing to a real intelligence intervention we know of.
Practice effects: real, but know what they are
Take the same IQ test twice and your second score will usually be higher — typically by several points — even with no intervention in between. Psychologists call these practice effects, and they're well documented. Familiarity with matrix puzzles, number series and spatial rotations removes the novelty penalty and lets your actual reasoning show. This cuts two ways. It means a single cold test, especially an online one, can underestimate you — online scores are estimates for self-knowledge, not clinical diagnoses. It also means training on test-style problems genuinely improves your performance on them. That's not fake improvement — fluency in abstract problem formats is a real skill — but it's a gain in test performance and trained abilities, not a rewiring of general intelligence. Understanding what your percentile means helps you read those gains honestly.
Brain training: honest about the transfer problem
Commercial brain-training games reliably make you better at the games. The open question has always been far transfer: does practicing a working-memory game make you smarter at everything else? The weight of evidence says mostly no. Reviews of the literature find strong improvement on trained tasks, modest transfer to very similar tasks, and little convincing evidence of broad IQ gains. In 2016 the US Federal Trade Commission fined Lumosity's maker $2 million for advertising claims the science didn't support. The lesson isn't that cognitive training is useless — it's that its benefits are specific. Train the abilities you actually want to improve: if you want faster mental arithmetic, sharper pattern recognition or better working-memory strategies, practice those directly and expect gains there, not everywhere.
Sleep, exercise and health: protect the score you have
The fastest way to lose 5–10 points on a test is to take it exhausted. Sleep deprivation measurably impairs attention, working memory and reasoning — the exact ingredients of fluid intelligence. Regular aerobic exercise is linked to better executive function and long-term brain health, and cardiovascular fitness protects cognition as you age (relevant reading: how IQ changes with age). None of this raises your ceiling; all of it determines whether you perform at your ceiling or well below it. If your goal is your best score — or your best thinking at work — sleep, movement and managing stress are the cheapest points available.
Nutrition: decisive in childhood, marginal in adulthood
Environment matters most while the brain is developing. Iodine deficiency, severe early malnutrition and lead exposure demonstrably lower childhood IQ, and fixing them produces real gains — iodized salt is one of history's most effective intelligence interventions. Breastfeeding and general early-childhood nutrition show smaller positive associations. For a well-nourished adult, though, no supplement has convincingly raised IQ. Eat for cardiovascular health and you've captured essentially all the cognitive benefit food offers.
What realistic improvement looks like
| Approach | Realistic effect | Evidence strength |
|---|---|---|
| Additional education | ~1–5 IQ points per year, lasting | Strong (meta-analysis, causal designs) |
| Practice / test familiarity | Several points on measured score | Strong, but test-specific |
| Sleep, exercise, cardiovascular health | Prevents underperformance; protects aging cognition | Strong for cognition broadly |
| Brain-training games | Big gains on trained tasks, limited far transfer | Strong on specificity of gains |
| Childhood nutrition (iodine, no lead) | Large where deficiencies exist | Strong, childhood only |
| "Boost your IQ 20 points" programs | — | No credible evidence |
Put together: an adult who takes on genuinely demanding learning, practices the specific abilities they care about, and shows up rested and healthy can plausibly move their measured score by a handful of points and their trained skills by much more. On a scale where 15 points is a full standard deviation, a few points is not trivial — it can move you a noticeable distance up the percentile ladder — but it's a far cry from the miracle-jump marketing.
The bottom line
Chasing a bigger number is the wrong frame. IQ is an estimate of general ability, and a "good" score matters far less than what you do with the specific abilities behind it. The evidence-based playbook is unglamorous: keep learning hard things, practice the skills you want (expecting gains in those skills, not universal genius), sleep, move, and treat any single test score — especially an online one — as a snapshot, not a verdict. That's also why we're upfront about our own training: it improves test performance and the specific abilities you drill. Nothing improves everything. Anyone who says otherwise is skipping the science.