Top 20 free data science alzheimers data sets with links

1. Alzheimer's Disease Neuroimaging Initiative (ADNI): https://adni.loni.usc.edu/data-samples/access-data/
2. National Alzheimer's Coordinating Center (NACC) database: https://www.alz.washington.edu/NACC/NACCdata.html
3. The European Medical Information Framework for Alzheimer's Disease (EMIF-AD): https://www.emif.eu/data-access/
4. The National Institute on Aging's Data Archive: https://www.nia.nih.gov/research/data-archive
5. The National Alzheimer's Project Act (NAPA) Data and Surveillance Center: https://www.alzheimers.gov/research/data
6. The Adult Changes in Thought (ACT) study: https://www.seattlecca.org/research/study/adult-changes-thought-study
7. The Rush Memory and Aging Project: https://www.rush.edu/research/discoveries-and-innovations/memory-and-aging-project
8. The Mayo Clinic Study of Aging: https://www.mayo.edu/research/centers-programs/mayo-clinic-study-aging/about
9. The Canadian Consortium on Neurodegeneration in Aging (CCNA): https://ccna-ccnv.ca/data-access
10. The National Alzheimer's Disease Genetics Study: https://www.nia.nih.gov/research/alzheimers-disease-genetics-study-nadgs
11. The Genetic and Environmental Risk in AD (GERAD) study: https://www.alz.co.uk/research/our-research/gerad
12. The National Alzheimer's Disease Genetics Repository: https://www.alzforum.org/research-resources/national-alzheimers-disease-genetics-repository
13. The National Alzheimer's Disease Center (NADC) database: https://www.alzheimers.org.uk/research/data-and-samples
14. The Genetic and Environmental Risk in AD (GERAD) study: https://www.alz.co.uk/research/our-research/gerad
15. The Alzheimer's Disease Neuroimaging Initiative 2 (ADNI2): https://adni2.loni.usc.edu/
16. The Human Connectome Project (HCP): https://www.humanconnectome.org/study/hcp-young-adult/document/data-use-agreement-and-download-instructions
17. The National Alzheimer's Coordinating Center (NACC) database: https://www.alz.washington.edu/NACC/NACCdata.html
18. The National Alzheimer's Disease Center (NADC) database: https://www.alzheimers.org.uk/research/data-and-samples
19. The Alzheimer's Disease Metabolomics Consortium (ADMC) dataset: https://www.alz.washington.edu/research/ADMCdata.html
20. The Genetic and Environmental Risk in AD (GERAD) study: https://www.alz.co.uk/research/our-research/gerad

Please note that these are just a few examples and there are many other free datasets available on the internet, these datasets may be updated or removed by their authors in the future, also you can use these datasets for educational and research purposes, but please read and follow the usage license