A specific red light treatment made cartilage cells in a dish produce less of a key structural protein that helps keep joints healthy
Scientific Claim
Near-infrared light at 850 nm with 4 mW/cm² power density, pulsed mode, applied every other day for 120 seconds, significantly reduced collagen type II expression in cultured human chondrocytes from a 46-year-old female donor
Original Statement
“There was no significant increase in COL II protein levels in chondrocytes exposed to PBM (Fig. 6 A). On the contrary, stimulation with 4 mW/cm² at 850 nm (pulsed, every other day, p < 0.001) or 4 mW/cm² at 940 nm (continuous, daily, p = 0.002) significantly reduced COL II expression compared to control”
Evidence Quality Assessment
Claim Status
appropriately stated
Study Design Support
Design supports claim
Appropriate Language Strength
definitive
Can make definitive causal claims
Assessment Explanation
The study directly measured collagen type II expression with statistical significance for this specific parameter, so 'significantly reduced' is appropriate.
Evidence from Studies
Supporting (1)
Near-infrared photobiomodulation stimulates viability and cartilage matrix synthesis in human chondrocytes