Zinc is an essential micronutrient that is needed for numerous critical health functions in the body. It is estimated that 17 to 20% of the global population is at risk for zinc deficiency, with certain groups at higher risk. The provision of supplemental zinc is a convenient and effective option for treating zinc deficiency and maintaining healthy levels of zinc. Several zinc salts are available for use in supplements. However, little information is available comparing the absorption and bioavailability of these different chemical forms of zinc. In this narrative review, we provide an overview of zinc absorption and bioavailability, discuss indicators of zinc status and risk factors for zinc deficiency, and review clinical studies comparing the absorption and bioavailability of different chemical forms of zinc in humans. This review of the clinical evidence suggests that zinc glycinate and zinc gluconate are better absorbed than other forms of zinc.
Adequate consumption of nutrients that support infant neurodevelopment is critical among pregnant women and women of childbearing age. Understanding the potential effects of socioeconomic inequalities on nutrient gaps in these life stages is thus important for informing strategies to mitigate negative health consequences. Usual intake (foods and dietary supplements) of neurodevelopment-related nutrients was determined from 24 h recalls among women of childbearing age and pregnant women (20–44 years) using data from 2007–2018 NHANES. Usual intake was compared across household food security, poverty-to-income ratio (PIR), and household participation in federal food and nutrition assistance programs. Intake of EPA + DHA was universally low with >95% of all women (pregnant and non-pregnant) below the DGA recommendation from foods alone. Women in households that participated in the Supplemental Nutrition Assistance Program had a significantly lower intake of multiple nutrients relative to those who did not participate. For example, 50% had intakes below the estimated average requirement (EAR) for vitamin A (versus 32%), 42% were below the EAR for calcium (versus 33%) and 65% were below the EAR for magnesium (versus 42%). Similar gradients were observed by PIR and household food security, and among pregnant women whereby gaps were more evident in those experiencing socioeconomic inequalities. The use of dietary supplements attenuated shortfalls for most nutrients. These findings highlight a critical need to support the nutritional requirements for women of childbearing age and pregnant women.
The influence of individual macro- and micronutrients on absenteeism in the United States is largely unknown. The objective of this study was to determine whether nutritional status or nutrient intake were associated with absenteeism from school and work due to illness or injury. Data from NHANES 2003–2008 were used to assess nutrient intake from food and food plus supplements, nutritional biomarker levels, and school and work absenteeism per year in children and adults. Negative binomial regression models were used to predict mean days of missed work per year and to estimate incidence rate ratios (IRRs) of absenteeism by nutrient biomarker status. Of 7429 children, 77% reported missing school days (mean 4.0 days). Of 8252 adults, 51% reported missing work days (mean 4.9 days). Children and adults who reported more absent days had a significantly lower intake of protein and several essential micronutrients from the diet. When nutrients from supplements were included, this negative association was retained for protein, selenium, choline, and DHA in children and for protein, selenium, vitamin K, choline, potassium, fiber, octadecatrienoic acid, and lycopene in adults. Future studies are needed to ascertain whether dietary interventions, such as access to healthier food options and/or dietary supplements, can reduce absenteeism.
Background and objectives: Lutein and zeaxanthin (L+Z) are carotenoids highly concentrated in the macula to maintain macular pigment optical density (MPOD) throughout the lifespan. Studies have shown that an intake of 6–20 mg or higher of L+Z would be beneficial for visual function and cognition. The human body cannot synthesize L+Z and must obtain them from other sources. Objective: To determine the nutrient intake status of L+Z in US children (6–18 years) and adults (19–64 years), and how dietary supplements contribute to the total intake level of L+Z. Methods: Data from NHANES 2003-08 cycles were used to estimate the mean intakes of L+Z from food and food + supplements (F+S). Children and adults were analyzed according to age groups: 6–8 years, 9–13 years, and 14–18 years for children, and 19–30 years, 31–50 years, and 51–64 years for adults. Results: In adults (n = 8252), the mean (SE) dietary intake of L+Z from food was 1.322 mg (0.040), which was similar to the intake from F+S: 1.396 mg (0.041). For both adult men and women, the mean intake increased by age, with the lowest intake of 1.047 mg (0.039) from food in adult women aged 19–30 years, and the highest intake of 1.700 mg (0.069) from F+S in adult men aged 51–64 years. In children (n = 7429), the mean (SE) intake of L+Z was 0.743 mg (0.026) from food, and 0.748 mg (0.026) from F+S. The intake levels among all age groups in children were similar, with the lowest intake of 0.686 mg (0.028) from food in girls 14–18 years, and the highest intake of 0.801 mg (0.038) from F+S in boys 9–13 years. Discussion: We found that the dietary intake levels of L+Z in US were much lower than levels recognized to support brain and eye health. Supplementation only marginally increased the total intake, which may indicate a lack of consumer awareness. Efforts are needed to raise public awareness of the health benefits of L+Z and encourage more consumption of L+Z-containing food (dark leafy greens and yellow or orange fruits/vegetables) and supplements by establishing dietary guidance for L+Z. This research was funded by Pharmavite LLC.