Is there a link between excessive dopamine and future dementia risk?

I gave a talk for a group of optometrist this week, and I raised the issue of dopamine and dementia. An astute optometrist asked for references which I've included below. In a recent podcast, I looked into the connection between excessive dopamine and future dementia risk. If I am right in my hypothesis, the next generation is going to see skyrocketing levels of dementia if we do not find a cure before then. https://podcasts.apple.com/us/podcast/the-eye-show/id1569268568?i=1000654475184 Most of our young people are spending hours and hours on TikTok and social media, which is rewiring brain to blink less or partially blink, which is destroying the hidden meibomian glands of the eyelid which are crucial for vision and prevent dry eye symptoms and future eye pain. I also did mention the association of Rosacea with increased cancer risk, which was the basis of my research when I was at Harvard in the early 2000s. References are below for this as well. Sandra Cremers, MD, FACS Of note, there are no randomized control perspective studies, indicating the below theories are definitive. Rosacea and Cancer Risk 1. Rosacea and Malignancy Risk (Systematic Review) • Thapa L, Xia J, Guo W, et al. JMIR Dermatol., 2023. Link to study 2. Glioma Risk and Rosacea (Danish Cohort) • Egeberg A, Hansen PR, et al. JAMA Dermatol., 2016. 3. Cancer Risk in Danish Rosacea Patients • Egeberg A, Fowler JF Jr, et al. Cancer Epidemiol., 2017. 4. Rosacea and Cancer Risk in U.S. Women • Li W-Q, Zhang M, et al. Br J Cancer, 2015. 5. Rosacea and Cancer Association (China) • Long J, Li J, Yuan X, et al. Journal of Dermatology, 2019. Rosacea Review Dopamine and Neurotoxicity High dopamine levels may be neurotoxic due to oxidative properties, potentially leading to neurodegenerative diseases like Parkinson’s. In Alzheimer’s, dopamine receptor downregulation may stem from earlier-life dopamine excess, but more research is needed on this link. Effects of Excessive Dopamine • Impulse Control Issues: Difficulty controlling actions. • Aggression & Hyper-competitiveness: Increased aggressiveness and competitiveness. • Sleep Disruptions: Difficulty sleeping. • Mental Illness & Addiction: Linked to conditions like depression and addiction. Sources: 1. PMC4288432 2. PMC4174765 Notes: Rosacea and Cancer Risk https://pubmed.ncbi.nlm.nih.gov/37938876/ Thapa L, Xia J, Guo W, Usmani H, Miller D, Lozeau D. Rosacea and Its Association With Malignancy: Systematic Review. JMIR Dermatol. 2023 Nov 8;6:e47821. doi: 10.2196/47821. PMID: 37938876; PMCID: PMC10666011. 2. Egeberg A, Hansen PR, Gislason GH, Thyssen JP. Association of rosacea with risk for glioma in a Danish nationwide cohort study. JAMA Dermatol. 2016 May 01;152(5):541–5. doi: 10.1001/jamadermatol.2015.5549.2484646[DOI] [PubMed] [Google Scholar] 3. Egeberg A, Fowler JF Jr, Gislason GH, Thyssen JP. Rosacea and risk of cancer in Denmark. Cancer Epidemiol. 2017 Apr;47:76–80. doi: 10.1016/j.canep.2017.01.006.S1877-7821(17)30014-0 [DOI] [PubMed] [Google Scholar] 4. Li W-Q, Zhang M, Danby FW, Han J, Qureshi AA. Personal history of rosacea and risk of incident cancer among women in the US. Br J Cancer. 2015 Jul 28;113(3):520–3. doi: 10.1038/bjc.2015.217. https://europepmc.org/abstract/MED/26103573 .bjc2015217 [DOI] [PMC free article] [PubMed] [Google Scholar] 5. https://www.rosacea.org/rosacea-review/2019/fall/rosacea-associated-with-increased-risk-cancers Long J, Li J, Yuan X, et al. Potential association between rosacea and cancer: A study in a medical center in southern China. Journal of Dermatology 2019; 1-7 II. Excessive dopamine can potentially be neurotoxic to the brain. Research indicates that high levels of dopamine can be neurotoxic, particularly due to its oxidative properties when in excess. Studies show that elevated dopamine can lead to the formation of toxic compounds, such as dopamine quinones, which damage neurons. This neurotoxicity has been linked to Parkinson’s disease and other neurodegenerative conditions, where the imbalance in dopamine metabolism contributes to neuronal death. In Alzheimer’s, which is a particular form of dementia, there is a down regulation of dopamine receptors noted in the brain of these patients. It is possible that excessive dopamine in earlier life could downregulate dopamine receptors over time. Chronic high levels of dopamine can lead to receptor desensitization or downregulation, where the brain reduces receptor availability in response to the surplus. In Alzheimer’s disease, this downregulation could contribute to reduced dopamine receptor numbers observed in the condition. However, while this idea is plausible, more research is needed to confirm a direct link between early-life dopamine levels and receptor changes in Alzheimer’s disease. Some non-peptide chemicals that function as neurotransmitters in the central nervous system (CNS), such as dopamine and serotonin, have toxic effects 1– 4. Neurodegeneration can result from the deregulation of the concentration of these neurotransmitters 5– 7. Too much dopamine can rewire your brain to have issues with the following: Impulse control: High dopamine levels can make it difficult to control impulses, leading to actions that are regretted later. Aggression: Too much dopamine can lead to aggressive behavior. Hyper-competitiveness: High dopamine levels can make people hyper-competitive, taking everything as a challenge. Sleep issues: High dopamine levels can make it difficult to sleep. Mental illness: Imbalances in dopamine levels are linked to mental illnesses like depression, schizophrenia, and psychosis. Addiction: Dopamine plays a role in addiction, and certain drugs can interact with dopamine to create a habit-forming cycle. Dopamine is a neurochemical that helps motivate people to seek out rewards like food and sex. It's also important for learning. However, too much dopamine can lead to negative consequences. If you want to restore balance to your dopamine levels, you can try taking a 30-day break from things th https://pmc.ncbi.nlm.nih.gov/articles/PMC4288432/ https://pmc.ncbi.nlm.nih.gov/articles/PMC4174765/