James Flynn, a New Zealand political scientist, noticed something strange in the 1980s. IQ scores were climbing with every generation - roughly 3 points per decade. Over the course of a century, the population average shifted by 30 points. If your grandparents took a modern IQ test without adjusted norms, most of them would score in the below-average range. Does that mean we're smarter than they were?
The answer is more complicated than it seems. And it reveals a lot about whether IQ can actually be raised.
What IQ Actually Measures (and What It Doesn't)
The IQ test wasn't designed to measure "smartness." Alfred Binet created it in 1905 for Parisian schools to identify children who needed extra help. It was a practical tool, not a verdict on intellect.
Modern IQ tests measure a set of cognitive abilities - logical reasoning, pattern recognition, working memory, processing speed, spatial visualization. The result is always relative: a score of 100 means you're exactly at the average for your age group. Nothing more, nothing less.
What IQ doesn't measure? Creativity, practical problem-solving, social intelligence, motivation, persistence. A person with an IQ of 125 who never finishes anything will likely be less successful in life than someone with an IQ of 105 who is tenacious and works well with people.
So the first thing to clarify when asking "can you increase your IQ" is this: are we talking about a number on a test, or the actual ability to think better?
Fluid vs. Crystallized Intelligence
Psychologist Raymond Cattell introduced a distinction in 1963 that is central to this topic. He identified two types of intelligence:
Fluid intelligence (Gf) is the ability to solve novel problems without prior experience. You see a pattern you've never encountered before and have to figure out the logic behind it. This ability peaks around age 25 and then gradually declines. It's closely tied to brain biology.
Crystallized intelligence (Gc) is accumulated knowledge and skills. Vocabulary, domain expertise, life experience. It grows with age and, in healthy individuals, barely declines until late in life.
Why does this matter? Because most promises about "raising your IQ" run headfirst into the wall of fluid intelligence. That's extremely difficult to shift permanently. You build crystallized intelligence throughout your life simply by learning and gathering experience - but that's not what people usually mean when they talk about increasing IQ.
The Flynn Effect - How Entire Populations Get Higher Scores
Back to James Flynn. The 3-point-per-decade increase is real and confirmed across dozens of countries. But Flynn himself warned against simplistic interpretations. He didn't assume people were biologically smarter. Rather, the environment changed - better nutrition, fewer childhood infections, more years of education, a more complex world demanding abstract thinking.
What's interesting is that the Flynn Effect has started slowing down in some developed countries, and in a few cases, it has reversed. A Norwegian study by Bratsberg and Rogeberg (2018), drawing on data from 730,000 military conscripts, showed declining IQ scores for cohorts born after 1975. The causes remain unclear - researchers speculate about shifts in education, media habits, and environmental factors.
What does the Flynn Effect tell us about individual IQ improvement? Above all, that environment plays a massive role. Genetics set the boundaries of your cognitive potential, but where you land within those boundaries depends on conditions. Experts estimate that IQ heritability runs around 50-80% in adults (Plomin and Deary, 2015). The rest is environment.
Brain Training - Does It Work or Not?
Around 2010, "brain training" apps exploded in popularity. Lumosity, Elevate, Peak. Millions of users, billion-dollar valuations, and a promise: play 15 minutes a day and boost your IQ.
Reality is more sobering. In 2016, a team led by Daniel Simons published a comprehensive meta-analysis in Psychological Science in the Public Interest. The conclusion? People who practice brain-training games get better at those specific games. But the improvement doesn't transfer to other cognitive tasks. You'll get better at the dual n-back task, but you won't solve problems at work any faster.
This is known as the "far transfer" problem - the transfer of a skill from a training context to the real world. And that's exactly what commercial brain-training programs consistently fail to demonstrate. The U.S. Federal Trade Commission (FTC) even fined Lumosity in 2016 for deceptive advertising.
Working memory may be an exception. Some studies (Jaeggi et al., 2008) suggested that intensive working memory training could briefly increase fluid intelligence. But later replication attempts produced mixed results. The scientific consensus so far: don't expect miracles.
What Actually Works for Cognitive Performance
None of the following will add 20 IQ points. But each one measurably affects how well your brain performs. And combined, the difference can be significant.
Aerobic Exercise
This is probably the most powerful thing you can do for your brain. A meta-analysis by Colcombe and Kramer (2003) showed that aerobic exercise improves executive functions - planning, attention switching, impulse inhibition. A study on older adults (Erickson et al., 2011) found that regular walking increased the volume of the hippocampus, a structure linked to memory and learning.
You don't need to run a marathon. Thirty minutes of brisk walking five times a week is enough. The effect becomes measurable after just six months.
Sleep
A single sleepless night reduces cognitive performance to a level comparable to mild intoxication. Research by Williamson and Feyer (2000) showed that 17 hours without sleep is equivalent to a blood alcohol level of 0.05%. Chronic sleep deprivation (under 6 hours per night) is even more insidious because you adapt to it and stop noticing how much it slows you down.
Sleep is when the brain consolidates memory traces and clears out metabolic waste. It's probably the most underrated factor in cognitive performance. How many hours do you sleep? And how much of that is truly quality sleep?
Learning New Skills
Not repeating what you already know. New skills - a musical instrument, a foreign language, programming, chess. A study from the University of Edinburgh (Bak et al., 2014) found that learning a second language slows cognitive aging, even when you start in adulthood.
The key is that frustrating feeling of "I can't do this." That's the signal that your brain is building new neural pathways. Once an activity becomes routine, its cognitive benefit drops.
Nutrition
Your brain consumes roughly 20% of all the body's energy despite making up only 2% of body weight. Nutrient intake has a direct impact. Omega-3 fatty acids (fish, nuts), antioxidants (fruits, vegetables), and adequate iron and vitamin B12 form the foundation. The Mediterranean diet has been linked to slower cognitive decline in aging across several studies.
On the other hand, no single "superfood" will make you smarter. Dietary supplements marketed as "nootropics" mostly have minimal or no verified effect in healthy individuals.
The Right Question Isn't "How to Increase IQ"
Picture someone who sleeps 5 hours a night, doesn't exercise, eats mostly processed food, and whose primary mental activity is scrolling social media. Now picture that same person with 7-8 hours of sleep, regular physical activity, a balanced diet, and evenings spent reading or learning Spanish.
That person's IQ score might shift by a few points on a test. Or it might not. But their real-world ability to think, solve problems, focus, and learn will be incomparably better. And that's what actually matters.
Research on cognitive reserve (Stern, 2009) shows that people with richer mental lives - more education, more complex work, an active social life - maintain their cognitive functions longer, even when their brains show the same biological signs of aging. It's not about IQ points. It's about how effectively you use your brain.
If you're curious about where you currently stand across different cognitive areas - logical reasoning, pattern recognition, verbal ability - try our IQ test. It shows you not just an overall score but also the strengths and weaker spots in your thinking. Knowing exactly where you have room to improve is the first step toward changing something.