I do 18 hour fasts routinely but sometime throw in a couple of 16 hour fasting days for when I want to eat out with family. You might find this related discussion helpful also.
-- Low-carb healthy fat living. Intermittent fasting. What’s your why?
https://connect.mayoclinic.org/discussion/low-carb-healthy-fat-living-intermittent-fasting-whats-your-why/
Before I learned about intermittent fasting none of my doctors ever mentioned the metabolic syndrome they just kept telling me I was in the pre-diabetes category. There are a lot of connections to neurologic and other conditions with the metabolic syndrome. Here are some of the references I've found on my journey.

-- Diagnosis and Management of the Metabolic Syndrome
https://www.ahajournals.org/doi/10.1161/circulationaha.105.169404
-- The metabolic syndrome – What is it and how should it be managed?
https://journals.sagepub.com/doi/full/10.1177/2047487319886404
-- A comprehensive definition for metabolic syndrome
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2675814/
-- The Metabolic Syndrome and Neuropathy: Therapeutic Challenges and Opportunities: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3881591/
-- Metabolic syndrome as a risk factor for neurological disorders
https://pubmed.ncbi.nlm.nih.gov/21997383/