Boron is a mineral that is found in certain foods. The best sources of dietary boron are fruits and vegetables. Some good sources of boron include prunes, raisins, apricots, green leafy vegetables (such as collards, kale, and spinach), nuts (especially almonds and pistachios), and legumes (such as soybeans and lentils). Brewer's yeast, wheat germ, and corn tortillas are also good sources of dietary boron. https://borates.today/boron-supplements/
While it is difficult to get too much boron from foods, it is possible to reach the upper limit of safe intake. The tolerable upper limit (UL) for boron has not been set, but it is thought that intakes up to 20 mg/day are safe. Some excellent dietary sources of boron include almonds, Brazil nuts, hazelnuts, and pecans. One cup of chopped almonds contains 2.1 mg of boron, and a half-cup of Brazil nuts contains 7.3 mg of the mineral.