Increased fruit and vegetable consumption is associated with a greater reduction in oxidative capacity and inflammation due to their phytochemicals with antioxidant properties and anti-inflammatory effects
Increased vegetable intake according to Dietary Guidelines for Americans (DGA) may be beneficial to bone health, finds a new study. Consuming vegetables at the DGA recommended amount increased urinary pH, decreased urinary acid and Mg excretion, and decreased the serum concentration of the bone resorption marker CTX. It at least transiently improves bone physiology and may benefit bone health in overweight or obese adults.
The study has been published in the Journal of Nutrition.
Controlled intervention trials are needed to confirm a positive association from epidemiological studies between vegetable consumption and bone health.
The researchers investigated whether providing vegetables at the Dietary Guidelines for Americans (DGA) recommended amount affects excretion of acid and calcium in urine and bone turnover markers in serum in adults with low vegetable intake.
In total, 102 adults (19 males and 83 females, age 18–65 y, BMI ≥25 kg/m2) consuming ≤1 serving of vegetables (128 g raw leafy or 64 g cooked vegetables) per d were recruited in a 2-arm, parallel, randomized, controlled, and community-based 8-wk feeding intervention trial. The 2 arms included a vegetable intervention (VI) during which participants received extra vegetables (∼270 g/d) and an attention control (CON) group that conducted only the testing visits. Measurements included nutrient intake, plasma carotenoids, and bone-related markers in serum and urine. Differences between CON and VI at week 8 were tested using the ANCOVA with baseline values as a covariate.
The Results of the study are as follows:
Compared with CON, carotenoid intake (mean ± SD) was higher (6.4 ± 3.4 compared with 2.0 ± 1.2 mg/d) (P < 0.01) and dietary potential renal acid load was lower (20 ± 13 compared with 3.4 ± 14 mEq/d) (P < 0.01) in VI. Compared with CON at week 8, urine titratable acid and Mg were 24 and 26% lower, respectively, while urine pH was 3% greater (P < 0.05) and serum C-terminal telopeptide of type I collagen (CTX) was 19% lower in VI. There were no group differences in serum concentrations of propeptide of type 1 procollagen and tartrate-resistant acid phosphatase or urinary excretion of deoxypyridinoline and CTX.
Thus, the researchers concluded that consumption of vegetables at the DGA-recommended amount by adults with low vegetable intake potentially benefits bone health. This trial was registered at clinicaltrials.gov as NCT02585102.
Reference:
Increasing Vegetable Intake Decreases Urinary Acidity and Bone Resorption Marker in Overweight and Obese Adults: An 8-Week Randomized Controlled Trial by Jay J Cao et al. published in the Journal of Nutrition.
https://doi.org/10.1093/jn/nxab255