Nicotine’s Effects on the Brain & Body & How to Quit Smoking or Vaping | Huberman Lab Podcast #90

Key Concepts

Nicotine, smoking, vaping, addiction, dopamine, acetylcholine, epinephrine, mesolimbic reward pathway, nicotinic receptors, POMC neurons, endothelial cells, homeostasis, withdrawal, hypnosis, Bupropion, nicotine replacement therapy.

Nicotine: A Comprehensive Overview

Introduction

The podcast discusses nicotine, a widely consumed substance, separating its effects from the delivery methods like smoking and vaping. It aims to provide a deep understanding of nicotine's impact on the brain and body, including potential benefits and drawbacks, while highlighting the dangers of smoking and vaping.

Huberman Lab Podcast Partnership with Momentous Supplements

The Huberman Lab Podcast has partnered with Momentous Supplements due to their international shipping, high-quality supplements, and single-ingredient options. Supplements can be found at livemomentous.com/huberman.

Focus Toolkit Recap

Two key protocols for enhancing focus from a previous episode are highlighted:

1. 13-Minute Daily Meditation: A simple meditation practice involving focusing attention on a point just behind the forehead can significantly improve focus ability.
2. Arrow Model of Focus: This model simplifies the neurochemistry of focus, where:
   • Acetylcholine: Sets the direction of focus (arrowhead).
   • Epinephrine/Adrenaline: Provides the energy for focus (shaft).
   • Dopamine: Provides ongoing motivation (propeller/motor).
   • Alpha GPC (300mg) can be used to increase acetylcholine and epinephrine for enhanced focus. Garlic capsules (600mg) can offset potential TMAO increases from Alpha GPC.

What is Nicotine?

• Nicotine is found in the tobacco plant and in smaller concentrations in nightshades like tomatoes, eggplants, sweet peppers, and potatoes.
• It's a plant alkaloid believed to have evolved as a defense against insects, disrupting their nervous systems and fertility.
• In humans, nicotine's effects are different due to variations in receptors. It does not cause infertility in humans, but can reduce penile girth and cause sexual dysfunction due to changes in blood flow.

Nicotine's Journey into the Body

• Nicotine enters the bloodstream through inhalation (smoking, vaping) or absorption via mucosal tissues (mouth, nasal passages).
• Burning tobacco liberates nicotine for inhalation.
• Once in the bloodstream, nicotine binds to nicotinic acetylcholine receptors in the brain and body.

Effects of Nicotine on the Brain

• Nicotine's primary effects are mediated by binding to the alpha four beta two receptor in the brain.
• Mesolimbic Reward Pathway (Dopamine):
  • Nicotine triggers dopamine release in the nucleus accumbens, creating rewarding properties, increasing motivation, and promoting feelings of well-being.
  • It both increases dopamine and decreases GABA activity, further enhancing the reward effect.
• Acetylcholine:
  • Nicotine increases acetylcholine release, particularly from the nucleus basalis, which acts as a "neurochemical attentional spotlight," enhancing focus and concentration.
  • The effects are transient, lasting approximately 30-45 minutes.
• Epinephrine/Norepinephrine:
  • Nicotine triggers norepinephrine release from the locus coeruleus, increasing alertness, energy, and arousal.
• Appetite Suppression:
  • Nicotine activates POMC neurons in the hypothalamus, suppressing appetite and reducing the impulse to chew.
  • It also has a minor effect of increasing metabolism by 2-5%.

Effects of Nicotine on the Body

• Nicotine increases heart rate, blood pressure, and heart tissue contractility, indicating increased sympathetic tone.
• It can constrict blood vessels, leading to decreased penile girth.
• It has a somewhat relaxing effect on skeletal muscles.
• The combination of alertness and relaxed muscles is ideal for cognitive work but not for physical performance.

Dangers of Smoking, Vaping, Dipping, and Snuffing

• These methods damage endothelial cells, disrupting blood flow and nutrient delivery to all tissues.
• Cigarettes contain 4,000-7,000 toxins, including carcinogens like tar, ammonia, formaldehyde, and carbon dioxide.
• Smoking reduces lifespan by an estimated 14 years per pack of cigarettes smoked per day.
• Dipping increases the risk of mouth cancers 50-fold.
• Vaping increases the risk of stroke and peripheral vascular disease.
• These habits increase the risk of heart attack, stroke, cognitive decline, and sexual dysfunction.

Why People Use Nicotine Despite the Risks

• Nicotine is highly reinforcing due to its effects on the dopamine system.
• It provides cognitive enhancement (focus, alertness) and mood elevation.
• 70% of smokers want to quit but find it difficult due to the reinforcing properties and withdrawal effects.
• Withdrawal symptoms include agitation, craving, irritability, and nausea, starting as soon as four hours after the last nicotine ingestion.

Quitting Nicotine: Strategies and Approaches

• Clinical Hypnosis:
  • Developed by Dr. David Spiegel at Stanford, clinical hypnosis has a 23% success rate in smoking cessation.
  • The Reveri app (reveri.com) provides access to hypnosis scripts for smoking cessation.
• Pharmacologic Approaches:
  • Bupropion (Wellbutrin): Increases dopamine and norepinephrine, reducing withdrawal symptoms. It has a success rate of about 20%. Caution is advised due to seizure risk and potential interactions with liver/renal disease and other medications.
• Nicotine Replacement Therapy (NRT):
  • Using nicotine patches, gum, or nasal sprays to gradually reduce nicotine intake.
  • A combination of methods (patch, then gum, then nasal spray) is most effective due to varying absorption rates and effects on dopamine release.
• Understanding Homeostasis:
  • The body adjusts to nicotine by lowering baseline mood and arousal.
  • Quitting leads to a drop below baseline, causing withdrawal symptoms.
  • Getting through the first week is critical, using healthy methods to increase dopamine (cold showers, exercise, social interaction).
• Relapse Prevention:
  • Avoid alcohol consumption, as it increases the risk of relapse.
  • Consider monthly or weekly hypnosis sessions to reinforce neural circuits that support abstinence.

Vaping: A Growing Concern

• Vaping delivers nicotine into the bloodstream faster than cigarette smoking, similar to crack cocaine.
• The rapid dopamine release makes vaping highly addictive, especially for young people.
• Vaping is associated with increased levels of depression, particularly when use drops off.
• The precise control over dopamine release through vaping can lead to a dependence on specific patterns of dopamine release.

Conclusion

Nicotine is a powerful substance with significant effects on the brain and body. While it can provide cognitive enhancement, the delivery methods like smoking and vaping pose severe health risks. Understanding the biology of nicotine and the strategies for quitting can empower individuals to overcome addiction and improve their overall health.