Boron is a trace element found mainly in plant foods. It is essential for plants, where it contributes to cell-wall structure, growth, pollination, and seed formation. In humans, the situation is less clear. Boron is not officially classified as an essential nutrient, because no single indispensable biochemical function has been identified. However, several human and animal studies suggest that boron may influence calcium, magnesium, vitamin D, steroid hormones, inflammation, and bone metabolism.

This makes boron an interesting nutrient-like mineral: we should not treat it like calcium or magnesium, where deficiency syndromes are well established, but we should also not dismiss it as irrelevant.