Mechanisms by which fruit and vegetables influence postmenopausal bone health: a randomised controlled trial in a well-characterised population

INTERVENTION: Minimisation criteria included key genotypes (vitamin D receptor genotype and Apolipoprotein E genotype, smoking and dietary acidity (calculated from protein to potassium ratio). Group A: potassium citrate equivalent to 900 g fruit and vegetables (55.5 mEq) Group B: potassium citrate equivalent to 300 g fruit and vegetables (18.5 mEq) Group C: 300 g of fruit and vegetables Group D: placebo Duration of treatment was two years for each treatment arm. CONDITION: Low bone mass/risk of osteoporosis ; Musculoskeletal Diseases ; Osteoporosis PRIMARY OUTCOME: 1. Bone turnover markers: ; a. serum N‐terminal Propeptide of type 1 collagen (P1NP), measured at baseline, 3, 6, 12, 18 and 24 months; b. serum C‐terminal telopeptide of type I collagen (CTX), measured at baseline, 3, 6, 12, 18 and 24 months; c. urinary free Deoxypyridinoline cross‐links (fDPD), measured at baseline, 3, 6, 12, 18 and 24 months; women also posted a fasted urine sample 6 to 8 weeks after the baseline visit SECONDARY OUTCOME: Bone mineral density change over two years measured by DEXA at baseline and 24 months. INCLUSION CRITERIA: Women aged 55 years to 65 years who had taken part in a longitudinal study (Aberdeen Prospective Osteoporosis Screening Study). Includes: 1. Otherwise healthy women taking other types of diuretics (not potassium sparing diuretics) or hypertension tablets 2. Women on thyroxine treatment provided their thyroid function is stable (as assessed by free Thyroxine [T4] and Thyroid Stimulating Hormone [TSH] levels) and their dose had not changed in the year prior to study entry