Evidence-based clinical recommendations regarding fluoride intake from reconstituted infant formula and enamel fluorosis: a report of the American Dental Association Council on Scientific Affairs.

BACKGROUND: This article presents evidence-based clinical recommendations regarding the intake of fluoride from reconstituted infant formula and its potential association with enamel fluorosis. The recommendations were developed by an expert panel convened by the American Dental Association (ADA) Council on Scientific Affairs (CSA). The panel addressed the following question: Is consumption of infant formula reconstituted with water that contains various concentrations of fluoride by infants from birth to age 12 months associated with an increased risk of developing enamel fluorosis in the permanent dentition? TYPES OF STUDIES REVIEWED: A panel of experts convened by the ADA CSA, in collaboration with staff of the ADA Center for Evidence-based Dentistry (CEBD), conducted a MEDLINE search to identify systematic reviews and clinical studies published since the systematic reviews were conducted that addressed the review question. RESULTS: CEBD staff identified one systematic review and two clinical studies. The panel reviewed this evidence to develop recommendations. CLINICAL IMPLICATIONS: The panel suggested that when dentists advise parents and caregivers of infants who consume powdered or liquid concentrate infant formula as the main source of nutrition, they can suggest the continued use of powdered or liquid concentrate infant formulas reconstituted with optimally fluoridated drinking water while being cognizant of the potential risks of enamel fluorosis development. These recommendations are presented as a resource to be considered in the clinical decision-making process. As part of the evidence-based approach to care, these clinical recommendations should be integrated with the practitioner's professional judgment and the patient's needs and preferences.

Macular pigment optical density at four retinal loci during 120 days of lutein supplementation.

BACKGROUND: Increased consumption of lutein and zeaxanthin has been shown to increase macular pigment optical density (MPOD) in some individuals. Most interventions either obtained infrequent measures of MPOD or measured MPOD at a single retinal locus. PURPOSE: The aim of this study was to measure acute changes in MPOD at four retinal loci during lutein intervention. METHODS: For 120 days, three subjects consumed 30 mg of lutein and 2.7 mg of zeaxanthin supplement per day. MPOD was measured with heterochromatic flicker photometry at 20', 30', 60' and 120' eccentricity three or four times per week. High-performance liquid chromatography was used to measure serum carotenoid concentrations in blood samples collected at baseline and at 30-day intervals. RESULTS: At the two most central loci, MPOD significantly increased in all three subjects with a mean change of approximately 0.09 log units at 20' eccentricity and 0.08 log units at 30' eccentricity. MPOD significantly increased in two subjects at 60' eccentricity, and in one subject at 120' eccentricity. The increases in MPOD appeared to be linear and continued after treatment was ended. In all three subjects, log sensitivity at the reference locus decreased linearly. Serum lutein and serum zeaxanthin increased from baseline, reaching peak concentrations after 30 days of supplementation. CONCLUSION: The changes in MPOD suggest that carotenoid deposition occurs linearly and may be biased towards the central retina. Further, carotenoid deposition may occur outside the central fovea in interventions with pharmacological doses of carotenoid, resulting in underestimations of psychophysical measures of MPOD.

Spinach cultigen variation for tissue carotenoid concentrations influences human serum carotenoid levels and macular pigment optical density following a 12-week dietary intervention.

Increasing intakes of carotenoid-rich plant foods can increase serum carotenoid concentrations and macular pigment optical density (MPOD) in most, but not all, individuals. Research objectives for this study were to (1) characterize tissue lutein (L) and beta-carotene (BC) concentrations in carotenoid-rich spinach (Spinacia oleracea L.) cultigens and (2) determine serum carotenoid and MPOD responses in human subjects consuming spinach cultigens differing in tissue L and BC concentrations. Thirteen spinach cultigens were evaluated for carotenoid accumulations over two consecutive growing seasons. "Springer" (8.4 and 6.5 mg/100 g of fresh mass for L and BC, respectively) and "Spinner" (12.1 and 9.2 mg/100 g of fresh mass for L and BC, respectively) spinach cultigens were selected for a dietary intervention study and represented low- and high-L concentrations. The high-L ("Spinner") and low-L ("Springer" ) spinach treatment groups consisted of 10 subject volunteers ingesting five 50-g spinach servings/week during a 12-week intervention. Average serum L concentrations increased by 22% (P = 0.07) from baseline (0.233 micromol/L) to 12 weeks (0.297 micromol/L) for subjects consuming low-L spinach. Subjects consuming high-L spinach showed increases of 33% (P = 0.04) in serum L from baseline (0.202 micromol/L) to 12 weeks (0.300 micromol/L). Average MPOD did not change for the low-L treatment group; however, subjects in the high-L group demonstrated increases (P = 0.02) in MPOD at the 30' eccentricity between baseline (0.343) and 12 weeks (0.374). This study demonstrates that serum carotenoid and MPOD are determined by L concentrations present in the spinach matrix. Results emphasize the role of cultigen selection among vegetable crops in determining phytochemical effects on human health.

A 12-wk egg intervention increases serum zeaxanthin and macular pigment optical density in women.

Two carotenoids found in egg yolk, lutein and zeaxanthin, accumulate in the macular retina where they may reduce photostress. Increases in serum lutein and zeaxanthin were observed in previous egg interventions, but no study measured macular carotenoids. The objective of this project was to determine whether increased consumption of eggs would increase retinal lutein and zeaxanthin, or macular pigment. Twenty-four females, between 24 and 59 y, were assigned to a pill treatment (PILL) or 1 of 2 egg treatments for 12 wk. Individuals in the PILL treatment consumed 1 sugar-filled capsule/d. Individuals in the egg treatments consumed 6 eggs/wk, containing either 331 microg (EGG 1) or 964 microg (EGG 2) of lutein and zeaxanthin/yolk. Serum cholesterol, serum carotenoids, and macular pigment OD (MPOD) were measured at baseline and after 4, 8, and 12 wk of intervention. Serum cholesterol concentrations did not change in either egg treatment group, but total cholesterol (P = 0.04) and triglycerides (P = 0.02) increased in the PILL group. Serum zeaxanthin, but not serum lutein, increased in both the EGG 1 (P = 0.04) and EGG 2 (P = 0.01) groups. Likewise, MPOD increased in both the EGG 1 (P = 0.001) and EGG 2 (P = 0.049) groups. Although the aggregate concentration of carotenoid in 1 egg yolk may be modest relative to other sources, such as spinach, their bioavailability to the retina appears to be high. Increasing egg consumption to 6 eggs/wk may be an effective method to increase MPOD.