This question is commonly asked among different kava venues online. The traditional wisdom is to have an empty stomach when consuming kava because the effects will be greater, but we rarely hear why. The digestion time varies among individuals. Research has indicated 50% of the stomach’s contents are emptied in 2.5–3 hours after eating. Total emptying of the stomach took 4–5 h [1]. Kava exerts its effect because kavalactones are lipophilic and mainly pass through the small intestine to enter the bloodstream [2]. The more quickly we can deliver these kavalactones to the small intestine, the faster and stronger the effects will be. When our last meal is still sitting heavily in our stomachs, kavalactones require excess time to reach the walls of the small intestine. This reduces the effects and lengthens the time normally observed for kava to take effect.
According to research, this time frame officially ranges from 3.5 to 5 h after your last full meal.
[1] Gastrointestinal transit: How long does it take? (n.d.). Retrieved March 10, 2021, from http://www.vivo.colostate.edu/hbooks/pathphys/digestion/basics/transit.html
[2] Drug absorption in the small intestine: Deranged physiology. (n.d.). Retrieved March 10, 2021, from https://derangedphysiology.com/main...Chapter 1.3.4/drug-absorption-small-intestine