Why does caffeine affect some more than others?
Sep 17, 2026 · 9m
Summary
Andrea Gilligan explores why coffee affects individuals differently, discussing caffeine’s half-life and its impact on sleep and pregnancy with registered dietitian Orla Walsh. They highlight significant inconsistencies in caffeine content across coffee shops and the high consumption rates in Ireland, where double-shot drinks are the industry standard. Oliver from Wall and Qo Teas contrasts this with Mediterranean habits, noting that Irish coffee culture is heavily ritualized. The episode concludes with advice to monitor personal tolerance, as factors like hormones, stress, and age can alte…
Topics discussed
Introduction and coffee consumption habits
Guest introduction: Orla Walsh, registered dietitian
Caffeine half-life and how long it stays in the body
Historical vs modern coffee consumption
Variability in caffeine content across coffee shops
Inconsistency of caffeine in different cafes
Advice for pregnant women and decaf options
Impact of caffeine on sleep quality
Caffeine and insomnia or waking up tired
Caffeine content in tea vs coffee
The psychology of coffee addiction and perceived benefits
Health benefits of coffee beyond caffeine
Finding your personal caffeine tolerance
Introduction of Oliver from Wall and Qo Teas
Morning coffee rituals and double shots in Ireland
Comparison of Irish vs Mediterranean coffee culture
Debate on single vs double shots and cultural norms
Individual variation in caffeine tolerance
Coffee as a cultural ritual and American influence
History of coffee adoption in Ireland
Listener comments on age and caffeine needs
ADHD and unexpected reactions to coffee
Caffeine in energy drinks and colas
Factors changing caffeine tolerance over time
Closing advice and guest sign-off
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