There is a tribe of Indians in Peru that live in total isolation. They are known to be very vicious, and are feared by all. Researchers found that the major staple of their diet was potatoes — one of the high-glycemic carbohydrates that causes a drop in blood sugar.

When they tested the tribal members for reactive hypoglycemia, they found it to be very common.

Similar studies conducted on prison populations also found a strong link between reactive hypoglycemia and violence among inmates.

Correcting the low blood sugar significantly improved inmate violence. Prison officials may be able to create better behaved inmates simply by changing their diet.