Supplement analysis backed by scientific evidence · PT

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Limited evidenceJoints & skin

Calcium Fructoborate

A plant-style boron-carbohydrate complex studied mainly for knee discomfort. Two small trials from the ingredient's developers reported symptom relief; nobody has independently replicated them.

Evidence last reviewed: August 2026

What the science says

  • Knee discomfort Limited evidence

    A double-blind, placebo-controlled study in subjects with knee discomfort found that 110 mg twice daily reduced WOMAC and McGill pain scores by day 14, with no change in the placebo group. The study was short, small, and conducted by the ingredient manufacturer.

  • Inflammatory markers Limited evidence

    A double-blind placebo-controlled pilot study in middle-aged people with primary osteoarthritis reported reductions in CRP and some lipid markers. It was explicitly a pilot with a small sample, and the biomarker changes were not linked to clinical outcomes.

  • Compared with established joint supplements Limited evidence

    Calcium fructoborate has not been tested head-to-head against glucosamine, chondroitin or NSAIDs in any published trial. All the human evidence traces back to two related research groups.

Dosage & safety

Studied dose110 mg twice daily (about 3 mg elemental boron per day) is the dose used in the published trials.
SafetyWell tolerated at studied doses. Boron intake above roughly 20 mg/day in adults is considered the upper limit and higher intakes can cause nausea and, in animal studies, reproductive toxicity. Avoid during pregnancy, and avoid in people with hormone-sensitive conditions, since boron can modestly raise sex hormone levels.

Scientific references

Where to buy

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