Nicotine

Nicotine can temporarily boost alertness, focus, and motivation, but it is highly reinforcing and difficult to quit; smoking and vaping also carry serious health risks. 1 2

• 1. Nicotinic receptors and acetylcholine: Nicotine acts at nicotinic acetylcholine receptors, with alpha-4 beta-2 receptors highlighted as important in the brain. It can increase acetylcholine signaling, which helps sharpen attention and focus for a limited time. 3 4
• 2. Appetite, metabolism, and performance: Nicotine can suppress appetite and increase metabolism. It also relaxes skeletal muscle, which can hinder the fast, coordinated muscle activation needed for physical performance; it is therefore a poor choice as a performance aid. 5 6 7
• 3. Reward and addiction: Nicotine increases dopamine in the mesolimbic reward pathway, contributing to its rewarding and reinforcing effects and making it difficult to quit. 1
• 4. Nicotine gum and neurodegeneration: Some people use nicotine gum for focus, but the suggestion that nicotine might protect against cognitive impairment is not established here as a proven way to prevent Parkinson’s or Alzheimer’s. 8 9
• 5. Belief and perceived cognitive benefit: In a study, people given the same nicotine dose performed differently depending on whether they were told it was a low, medium, or high dose; stronger expectations were associated with better task performance and greater activity in a relevant brain area. 10

The delivery method matters: smoking harms lung and cardiovascular health, and nicotine itself can raise heart rate and blood pressure. 11 12