TABLE 2.

Summary of the main findings from the randomized controlled trials included in the present review assessing the effect of plant-based food interventions on telomere length

Study design	Country	Sample size	Telomere length assessment method	Intervention	Duration	Control diet	Association with telomere length	Reference
Parallel-group	Spain	520	qPCR (relative TL)	Mediterranean diet supplemented with extra-virgin olive oil and Mediterranean diet supplemented with mixed nuts	5 y	Low-fat diet	Participants on the Mediterranean diet supplemented with nuts showed a higher risk of telomere attrition compared with the control group	García-Calzón et al. (30)
Parallel-group	US	29	qPCR (relative TL)	Consumption of foods that included cooked navy bean powder and heat-stabilized rice bran	4 wk	Consumption of foods with no additional ingredient	No differences in TL were observed between groups	Borresen et al. (46)
Parallel-group	Spain	149	Quantitative fluorescence in situ hybridization (absolute)	Walnuts	2 y	Prestudy habitual diet (abstaining from walnuts)	Time × intervention interaction nearly significant (P = 0.079), suggestive of a trend of walnut consumption in preserving TL	Freitas-Simoes et al. (47)