How to Improve Your IQ: 7 Evidence-Based Methods That Actually Work

For decades, scientists believed IQ was essentially fixed by genetics and early childhood environment. Modern neuroscience paints a more nuanced picture: while IQ is relatively stable in adulthood, cognitive performance is genuinely plastic — shaped by lifestyle, habits, and deliberate practice. Here's what the research actually supports.

1. Exercise — The Strongest Evidence for Boosting Cognition

Aerobic exercise is probably the single most effective intervention for improving cognitive performance. Research consistently shows that regular cardiovascular exercise:

• Increases production of BDNF (brain-derived neurotrophic factor), which promotes neuronal growth
• Improves working memory and executive function
• Slows cognitive decline with age
• Increases hippocampal volume (the brain region critical for memory and learning)

A 2010 study in Proceedings of the National Academy of Sciences found that adults who walked 40 minutes three times per week for a year increased hippocampal volume by 2% — reversing age-related shrinkage. Aim for 150 minutes of moderate aerobic activity per week.

2. Sleep — The Brain's Maintenance Window

Sleep deprivation is cognitively catastrophic, yet chronically underappreciated. Even mild sleep restriction (6 hours per night for 2 weeks) impairs performance equivalent to two full nights of total sleep deprivation — and most people don't notice because the impairment comes on gradually.

During slow-wave sleep, the brain:

• Consolidates memories (transfers information from short-term to long-term storage)
• Clears metabolic waste products including amyloid-beta (associated with Alzheimer's)
• Strengthens synaptic connections formed during waking learning

Adults need 7–9 hours of quality sleep per night for optimal cognitive performance. Prioritising sleep is the highest-return investment in your cognitive health.

3. Working Memory Training

Working memory — the ability to hold and manipulate information in mind — is one of the strongest predictors of fluid intelligence and academic performance. Unlike many cognitive skills, there's genuine (though contested) evidence that working memory can be improved through targeted practice.

The most studied intervention is the dual n-back task — a demanding exercise that requires simultaneous tracking of two streams of information. Several studies have found training-related improvements in fluid IQ scores, though the magnitude and transfer to real-world tasks remain debated.

Practical working memory exercises include: mental arithmetic without paper, remembering sequences of numbers or words, and learning to play a musical instrument (which demands simultaneous tracking of multiple information streams).

4. Cognitive Challenge — Learning New Complex Skills

The brain follows a "use it or lose it" principle. Engaging in genuinely novel, complex cognitive challenges — not just more of what you already do well — drives neuroplasticity.

Activities with strong cognitive benefit include:

• Learning a second language: Requires simultaneous management of two linguistic systems and is associated with better executive function and delayed dementia onset
• Playing chess or Go: Both demand pattern recognition, working memory, and strategic planning
• Musical instrument study: Particularly effective for children; significant evidence for improving processing speed, working memory, and verbal reasoning
• Complex reading: Dense non-fiction, philosophy, and literary fiction all require sustained attention and vocabulary expansion

The key is novelty and challenge — doing puzzles you've mastered doesn't drive the same neural adaptation as tackling unfamiliar cognitive demands.

5. Nutrition — Brain Food Is Real

The brain consumes roughly 20% of your body's total energy despite being only 2% of your body weight. Nutritional status meaningfully affects cognitive performance:

• Omega-3 fatty acids (especially DHA): Critical for neuronal membrane integrity. Found in fatty fish, walnuts, and flaxseed. Deficiency is associated with cognitive impairment.
• Iron: Even mild iron deficiency — common in menstruating women and growing children — impairs attention, memory, and learning.
• Iodine: Iodine deficiency is the world's leading preventable cause of intellectual disability. Still relevant in many populations.
• B vitamins: B12 deficiency causes neurological damage. Vegans are at particular risk without supplementation.

The Mediterranean diet — high in vegetables, fish, olive oil, and whole grains — is the most consistently evidence-supported dietary pattern for long-term cognitive health.

6. Meditation and Stress Reduction

Chronic stress elevates cortisol, which damages the hippocampus and impairs working memory and executive function. Mindfulness meditation has a growing evidence base for:

• Improving sustained attention and working memory capacity
• Reducing mind-wandering during cognitive tasks
• Reducing stress-related cortisol that impairs memory

A 2011 Harvard study found that just 8 weeks of mindfulness-based stress reduction (MBSR) training produced measurable increases in grey matter density in regions associated with self-awareness, compassion, and introspection.

7. Cognitive Testing and Feedback

Knowing your specific cognitive strengths and weaknesses allows you to target improvement efforts where they'll have the most impact. A domain-level cognitive profile shows whether your bottleneck is verbal reasoning, working memory, quantitative ability, or another area.

Take IQ Test Center's free cognitive assessment to identify your profile across five domains, then focus your training where you have the most room to grow. Learn more about how IQ is measured →

What the Research Doesn't Support

Despite widespread marketing:

• Brain training apps (Lumosity, Elevate, etc.) primarily improve your performance on the specific tasks in the app — transfer to general intelligence is limited
• Supplements marketed as "smart drugs" have weak or no evidence for healthy adults (with the exception of correcting specific deficiencies)
• Speed reading typically involves comprehension trade-offs rather than genuinely processing text faster