So, what's their average total caloric intake? Hmm... 2400-2700/day[1] which is not in the Lancet article[2], but I did find that in an American Journal of Clinical Nutrition reference[3]. It appears they get lots of exercise, which isn't surprising.
[1]https://coach.nine.com.au/2018/11/05/14/03/tsimane-diet-card...
[2]https://www.researchgate.net/publication/315262221_Coronary_...