The blue dye methylene blue cut the amount of a harmful chemical (hydrogen peroxide) in heart and blood vessel fat by about half when tested in the lab.
Scientific Claim
Methylene blue (0.1 µM, 24 h) reduces hydrogen peroxide production in human cardiovascular adipose tissue by approximately 30–50% as measured by the FOX assay, indicating a direct antioxidant effect in ex vivo tissue.
Original Statement
“H2O2 production was significantly reduced in the presence of MB in both types of adipose tissues, apparently in a higher degree in EAT as compared to PVAT. ... Values are means ± S.E.M; *p < 0.05.”
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 used a validated spectrophotometric assay to quantify H2O2 reduction with statistical significance. The claim reflects the measured effect without extrapolating to clinical outcomes.
Evidence from Studies
Supporting (1)
Methylene blue reduces monoamine oxidase expression and oxidative stress in human cardiovascular adipose tissue
The study found that a small amount of methylene blue, left on fat tissue from the heart for a day, lowered harmful chemicals called ROS—which include hydrogen peroxide—so the claim that it reduces them by 30–50% is supported.