Effect of intake of iron-fortified milk on levels of ferritin and hemoglobin in preschoolers: A systematic review and meta-analysis.

BACKGROUND: Food fortification is often the simplest way to increase iron intake on a broad and sustainable basis. It is one of the most cost-effective global development efforts. OBJECTIVE: To systematize data from randomized and nonrandomized controlled trials investigating the effect of consumption of iron-fortified milk (IFM) on serum iron status in preschoolers. METHODS: The trials were systematically searched in five electronic databases that evaluated the effect of iron-fortified milk (IFM) consumption on hemoglobin and ferritin in children aged 1-6 years. The randomized the meta-analysis model was used to calculate total and stratified effects. RESULTS: Seven trials representing 1210 preschoolers showed a significant effect of IFM on hemoglobin [difference in means (MD) 0.33 g/dL (95% CI 0.23, 0.44; I2 = 3.85%, p (Q statistic) < 0.01)] and ferritin concentrations [effect size (SMD) 0.57 (95% CI 0.19, 0.95; I2 = 84.63%, p (Q statistic) < 0.01)]. In stratified analyses, hemoglobin showed an increase when subjects received iron with other co-interventions [MD 0.35 g/dL (95% CI 0.22, 0.48; I2 = 11.01%; p (Q statistic) = 0.36)]; and when the iron dose was above 5 mg/day [MD 0.34 g/dL (95% CI 0.23, 0.45; I2 = 2.33%; p (Q statistic) = 0.37)] and the intervention time was over 6 months [MD 0.39 g/dL (95% CI 0.18, 0.60; I2 = 37.90%; p (Q statistic) = 0.20)]. For ferritin, stratified analyses showed a larger effect size when they used dose higher than 5 mg/day [SMD 0.60 (95% CI 0.02, 1.18; I2 = 91.06, p (Q statistic) < 0.01)] and intervention was conducted longer than 6 months [SMD 0.96 (95% CI - 0.16, 1.76; I2 = 93.38%, p (Q statistic) < 0.01)]. CONCLUSIONS: Our findings indicate that although milk iron fortification modestly increases serum hemoglobin levels or the effect size of serum ferritin of participants, it cannot be considered in the coadjuvant treatment for anemia. Register: CRD42020213604.

Seasonal Variation in Fat Quality and Conjugated Linoleic Acid Content of Dairy Products from the Tropics: Evidence of Potential Impact on Human Health.

Seasonal variation in conjugated linoleic acid (CLA) content and atherogenicity index (AI) of retail dairy products (whole milk, butter, and prato, a soft yellow cheese) from Brazil was investigated. CLA content of dairy products ranged from 0.55 to 1.53 g CLA/100 g fatty acids and was on average 25% higher during the rainy season compared to the dry season. Dairy products from the rainy season also had lower AI levels, indicating a lower risk of causing cardiovascular disease in consumers. This seasonality led to estimated seasonal variations of milk fat quality consumed by the population of southeastern Brazil, meaning 15% and 19% variation in daily intake of CLA and AI values, respectively. Dietary consumption of CLA (g/day) was greater in the rainy season, despite higher intake of dairy products during the dry season. We show that dairy products produced during the rainy season in Brazil are expected to be more beneficial to human health than are those produced during the dry season.