Eating more fruits and veggies for 3 months doesn’t help protect the DNA in blood cells from damage—even when those cells are stressed in the lab.
Scientific Claim
Increasing daily fruit and vegetable intake from approximately 3 to 8.4 portions for 12 weeks has no significant effect on lymphocyte DNA damage (endogenous or H2O2-induced) in healthy adults aged 39–58 with low baseline intake, suggesting no short-term genomic protective benefit.
Original Statement
“There were no significant changes in antioxidant capacity, DNA damage and markers of vascular health.”
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 RCT design with blinded, objective DNA damage assays supports a definitive conclusion of no effect. The authors appropriately avoid overstating protective claims.
Evidence from Studies
Supporting (1)
Even though people ate more fruits and veggies and their blood showed more healthy nutrients, their DNA didn’t become less damaged after 12 weeks—so eating more didn’t protect their genes in the short term.