Nicotine: The Research
Nicotine is the alkaloid of the tobacco plant, and in tiny amounts of tomatoes, potatoes, peppers and aubergines. It acts on the nicotinic acetylcholine receptors found throughout the brain, muscles, gut and immune system, which is why it is studied for far more than addiction: memory and Parkinson’s disease, bowel inflammation, mood, weight, pain and cancer biology, as well as for its toxicity. This section collects that research from PubMed, one page per topic, each paper summarised in plain language and linked to its PubMed record.
Nicotine is not the same thing as smoking. Most of the harm of cigarettes comes from burnt tobacco — tar, carbon monoxide and nitrosamines — and the papers here are about nicotine itself, its metabolites and its receptors. The collection is research only and is separate from the claims documented on the Dr. Bryan Ardis pages. It is not medical advice.
Table of Contents
By Topic
411 papers in the collection so far, updated weekly. A paper that fits more than one page is listed on each.
Brain and Memory
Attention, memory, mild cognitive impairment, Alzheimer's and Parkinson's disease: what the trials and the laboratory work on nicotine and the thinking brain report. 29 papers.
Read the research →Addiction and Withdrawal
How nicotine dependence forms in the reward system, what withdrawal does, and the research on quitting. 26 papers.
Read the research →Patches, Gum and Delivery
Patches, gum, lozenges, sprays, pouches and vapour: how each form delivers nicotine to the blood, and what the pharmacokinetic studies measure. 25 papers.
Read the research →Heart and Blood Vessels
Heart rate, blood pressure, arrhythmia and the lining of the arteries: what nicotine on its own, apart from smoke, does to the cardiovascular system. 22 papers.
Read the research →Toxicity and Safety
Overdose, child and pet poisoning, pregnancy, adolescent exposure and the lethal-dose question: the safety research on nicotine. 26 papers.
Read the research →Cancer Research
Nicotine is not the carcinogen in tobacco smoke, but it does act on tumour cells. Cell, animal and human studies on nicotine, its metabolites and cancer. 18 papers.
Read the research →Mood and Mental Health
Depression, anxiety, schizophrenia and ADHD: the research on why nicotine use runs so high in these conditions and what nicotine itself does to mood. 24 papers.
Read the research →Metabolism and Weight
Appetite, weight, insulin and blood sugar: the research behind the weight gain that follows quitting and what nicotine does to glucose control. 22 papers.
Read the research →Inflammation and Immunity
The cholinergic anti-inflammatory pathway, the alpha-7 receptor on immune cells, ulcerative colitis and sepsis: the research on nicotine as an immune signal. 17 papers.
Read the research →Metabolites and Chemistry
Cotinine, 6-hydroxy-nicotine, CYP2A6 and how the body breaks nicotine down: the research on nicotine's chemistry and its metabolites. 28 papers.
Read the research →By Condition
The conditions most often discussed with nicotine, each with its own research page.
Alzheimer's Disease
Nicotinic receptor loss, amyloid, and the patch trials in mild cognitive impairment: the published research on nicotine and Alzheimer's disease. 22 papers.
Read the research →Parkinson's Disease
Why smokers get Parkinson's less often, the dopamine-neuron studies, and the nicotine patch trials: the published research on nicotine and Parkinson's. 21 papers.
Read the research →COVID-19
The smoker paradox in early COVID-19 data, the nicotinic-receptor hypothesis, and the trials that tested nicotine patches against the virus. 17 papers.
Read the research →Arthritis and Pain
Rheumatoid arthritis, osteoarthritis, joint inflammation and nicotine's effect on pain: the published research. 24 papers.
Read the research →Ulcerative Colitis
Ulcerative colitis is the bowel disease that is rarer in smokers; the nicotine patch, enema and capsule trials and the gut-immune studies. 23 papers.
Read the research →Schizophrenia
Very high smoking rates in schizophrenia, the alpha-7 receptor gene, sensory gating and cognition: the published research on nicotine and schizophrenia. 17 papers.
Read the research →Type 1 Diabetes
Autoimmune diabetes, the pancreatic islets and the alpha-7 receptor: the published research on nicotine and type 1 diabetes. 11 papers.
Read the research →Autism
Nicotinic receptors in autism, prenatal nicotine exposure, and the small studies of nicotine on autism symptoms. 10 papers.
Read the research →Multiple Sclerosis
Snus, smoking and MS risk, and the animal studies of nicotine on brain inflammation and demyelination. 18 papers.
Read the research →Thyroid and Hashimoto's
Autoimmune thyroiditis is less common in smokers; the research on nicotine, thyroid hormone and thyroid autoimmunity. 26 papers.
Read the research →Heart Rhythm and Myocarditis
Arrhythmia, heart-muscle inflammation and nicotine's action on the heart's own receptors: the published research. 23 papers.
Read the research →Glioblastoma
Nicotinic receptors on glioma cells and the laboratory studies of nicotine, its metabolites and brain-tumour growth and treatment response. 8 papers.
Read the research →Newest in the Collection
- Investigating the potential risk of nicotine exposure on glioblastoma: Integrating Mendelian randomization and network toxicology analysis (2026, other) — Glioblastoma
- Developmental Nicotine Exposure Induces Intergenerational Transmission of an Ensemble of Neurodevelopmental Disorder-Related Translatomic Perturbations in DRD1-Expressing Striatal Cells of Adolescent Male Mice (2026, animal study) — Autism
- Very low nicotine content cigarettes for smoking cessation: Examining a facilitated extinction approach and dosing schedule (2026, human trial) — COVID-19
- Long-term WBE monitoring of alcohol, nicotine, and caffeine in two Spanish cities: COVID-19 impacts and beyond (2025, human observational study) — COVID-19
- Evaluation of high-nicotine oral products shows potential to reduce tobacco-related harm by offering satisfying alternatives (2025, human trial) — Multiple Sclerosis
- New nicotine products and vascular risk (2025, review) — Heart and Blood Vessels
- Oral adverse event reporting in smoking cessation trials using non-combustible nicotine products: A quality assessment (2025, review) — Multiple Sclerosis
- Oral health effects of non‑combustible nicotine products: a systematic review and network meta‑analysis of randomized controlled trials (2025, meta-analysis) — Multiple Sclerosis
- Joint effect of nicotine use and diabetes distress on glycemic control in young adults with type 1 diabetes (2025, human observational study) — Type 1 Diabetes
- The interpeduncular nucleus blunts the rewarding effect of nicotine (2025, animal study) — Parkinson's Disease
- Nicotine Attenuates Molecular Signalings in the BTBR T+ Itpr3tf/J Mouse Model of Autism (2025, animal study) — Autism
- Nicotine increases hepatocyte transthyretin turnover: A possible mechanism for the protective effect of smoking on preeclampsia? (2025, cell study) — Thyroid and Hashimoto's
How This Collection Is Built
- Each page runs its own PubMed search for papers in which nicotine is a major subject and that have an abstract. The search is linked at the bottom of every page.
- Each paper’s record — title, authors, journal, year, PMID and DOI — is taken from PubMed itself, never typed by hand, and retracted papers are skipped.
- The plain-language summary is written from the paper’s own abstract, keeping its numbers and saying whether the work was in cells, animals or people. Papers that only use nicotine as a marker of smoking are left out.
- New papers are added every week, and the newest appear at the top of each page.
Connections
- Medicines and Oils
- The Nicotine Patch, animated — how a patch, gum and a cigarette differ in the blood
- Dr. Bryan Ardis — his nicotine claims, documented on their own pages
- Nicotinic Acetylcholine Receptors
- Cigarette Smoke — what burnt tobacco adds that nicotine alone does not
- Vitamin B3 (Niacin) — named after nicotinic acid, an oxidation product of nicotine, but a different molecule