Boron: what it does and how much you need

Boron is a trace element found in plant foods. No daily need has been set for it. There is no set daily amount for boron, and the upper limit is 20 milligrams a day.

Checked 28 September 2026 with Supplement Check's data from the NIH fact sheet · Adults only

General information, not medical advice. Check with a doctor or pharmacist before taking a supplement, especially if you are pregnant or breastfeeding, take any medicine, or are under 18.

How much you need and the upper limit

Adults needNo set daily amount for boron
Upper limit20 milligrams a day

These are the US (NIH) figures for adults. Supplement Check has no separate NHS figure for boron.

Food sources

Quick answers

What does boron do?
Boron is a trace element found in plant foods. No daily need has been set for it.
How much boron do adults need?
There is no set daily amount for boron (US, NIH).
What is the upper limit for boron?
US: 20 milligrams a day.
Which foods have boron?
Prune juice, avocados, raisins, peaches, peanuts, apples.

Sources

Ask Supplement Check yourself

Type a vitamin, mineral or supplement, a dose, or a product name, and get the daily need, the upper limit and any cautions. Open Supplement Check, free, no sign-up.

In Claude or any app that takes MCP connectors, add https://goodturn-mcp.pages.dev/supplementcheck/mcp and ask: “How much boron do I need?”

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