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Background Dietary polyphenol intake has been associated with a decreased risk of hyperuricemia, but most of this knowledge comes from preclinical studies. The aim of the present study was to assess the association of the intake of different classes of polyphenols with serum uric acid and hyperuricemia. Methods and Results This cross-sectional analysis involved baseline data of 6332 participants. Food polyphenol content was estimated by a validated semiquantitative food frequency questionnaire and from the Phenol-Explorer database. Multivariable-adjusted linear regression models with serum uric acid (milligrams per deciliter) as the outcome and polyphenol intake (quintiles) as the main independent variable were fitted. Cox regression models with constant follow-up time (t=1) were performed to estimate the prevalence ratios (PRs) of hyperuricemia (≥7 mg/dL in men and ≥6 mg/dL in women). An inverse association between the intake of the phenolic acid class (β coefficient, -0.17 mg/dL for quintile 5 versus quintile 1 [95% CI, -0.27 to -0.06]) and hydroxycinnamic acids (β coefficient, -0.19 [95% CI, -0.3 to -0.09]), alkylmethoxyphenols (β coefficient, -0.2 [95% CI, -0.31 to -0.1]), and methoxyphenols (β coefficient, -0.24 [95% CI, -0.34 to -0.13]) subclasses with serum uric acid levels and hyperuricemia (PR, 0.82 [95% CI, 0.71-0.95]; PR, 0.82 [95% CI, 0.71-0.95]; PR, 0.80 [95% CI, 0.70-0.92]; and PR, 0.79 [95% CI, 0.69-0.91]; respectively) was found. The intake of hydroxybenzoic acids was directly and significantly associated with mean serum uric acid levels (β coefficient, 0.14 for quintile 5 versus quintile 1 [95% CI, 0.02-0.26]) but not with hyperuricemia. Conclusions In individuals with metabolic syndrome, a higher intake of some polyphenol subclasses (hydroxycinnamic acids, alkylmethoxyphenol, and methoxyphenol) was inversely associated with serum uric acid levels and hyperuricemia. Nevertheless, our findings warrant further research.

Studies of iron and its association with the risk of small for gestational age (SGA) show inconsistent results. Consuming iron supplements during pregnancy is controversial because of possible risks. This study assessed the association between iron intake and the risk of having an SGA newborn and whether iron intake is associated with gestational diabetes. A case-control study of 518 pairs of Spanish women who were pregnant and attending five hospitals was conducted. Groups were matched 1:1 for age (±2 years) and hospital. Cases were women with an SGA newborn at delivery. Controls were women with normal-sized newborns at delivery. Data were gathered on demographic characteristics, socio-economic status, adverse habits (like smoking), and diet. A 137-item food frequency questionnaire was completed. Iron intakes were categorized in quintiles (Q1-Q5). Crude odds ratios (ORs) and adjusted ORs (aORs) with 95% confidence intervals (CIs) were estimated by conditional logistic regression. No significant relationship was found between dietary iron intake and SGA. A protective association was found for women receiving iron supplementation >40 mg/day and SGA versus women not taking supplements (aOR = 0.64, 95% CI [0.42, 0.99]). This association was identified in mothers both with (aOR = 0.57, 95% CI [0.40, 0.81]) and without (aOR = 0.64, 95% CI [0.64, 0.97]) anaemia. In women in the control group without anaemia, iron supplementation >40 mg/day was positively associated with gestational diabetes (aOR = 6.32, 95% CI [1.97, 20.23]). Iron supplementation in pregnancy may prevent SGA independently of existing anaemia but may also increase the risk of gestational diabetes., (© 2019 John Wiley & Sons Ltd.)