A large (61,000 subject) observational study from Sweden published in British Medical Journal in 2018. (With the usual caveats about correlation not causation, non-randomization etc.). Nut consumption ≥3 times/week was associated with an 18% reduced risk of atrial fibrillation. Nuts are a great source of the following nutrients: unsaturated fatty acids protein fiber magnesium, potassium, zinc…
