Core Nutritional

Boron — 3 mg

💊 What it does

Boron is an ultra-trace mineral that has emerged as important for bone health, joint health, and hormone metabolism. It supports the conversion of vitamin D to its active form, enhances magnesium retention, and modulates sex hormone levels (testosterone and oestrogen). Evidence supports benefits for osteoarthritis, bone density, and cognitive function. It is one of the less well-known micronutrients but increasingly recognised as important.

👤 Who needs it

People with osteoporosis or osteoarthritis. Post-menopausal women — boron supports oestrogen metabolism and bone density. Those supplementing vitamin D (boron enhances D activation). Older adults seeking joint and cognitive support.

🥦 Food sources first

Good dietary sources: prunes (one of the richest sources), raisins, avocado, almonds, peanuts, hazelnuts, dried apricots, red wine, chickpeas, lentils, apples, pears, broccoli. A diet rich in fruits, vegetables, nuts, and legumes provides reasonable boron intake.

🗓 When to supplement

For bone and joint health support, particularly in post-menopausal women. As part of a vitamin D and magnesium protocol. When dietary fruit and vegetable intake is low.

🏷 Best form to look for

Calcium fructoborate is the best-studied form — naturally occurring in plant foods. Sodium borate is also used. 3 mg is the standard supplemental dose.

⏰ When to take it

Can be taken at any time with or without food.

⚡ Interactions & combinations
Works synergistically with vitamin D, magnesium, and calcium for bone health. May affect oestrogen and testosterone levels — those with hormone-sensitive conditions should consult GP.
🛡 Safety notes
Well tolerated at 3–6 mg/day. The UK upper limit is approximately 10 mg/day. Very high doses (above 20 mg/day) cause reproductive toxicity in animals — stay within recommended ranges.
🌿 Vegan note
Calcium fructoborate is derived from plant sources. Plant-based.
Moderate evidence
Good evidence, though not unanimous across all research.
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Disclaimer: As with any supplement, it is best to consult with a healthcare professional before starting, particularly if you are pregnant, nursing, or taking prescription medications.