Impact of Maternal Daily Oral Low-Dose Vitamin A Supplementation on the Mother-Infant Pair: A Randomised Placebo-Controlled Trial in China

Use of Theoretical Women and Model-Based Compartmental Analysis to Evaluate the Impact of Vitamin A Intake with or without a Daily Vitamin A Supplement on Vitamin A Total Body Stores and Balance During Lactation

BACKGROUND

Inadequate vitamin A (VA) intake is common among lactating women in many communities worldwide, but high-dose VA supplementation for postpartum women is not recommended by the World Health Organization as an effective intervention.

OBJECTIVES

To simulate the impact of VA intake via diet and daily VA supplements on VA total body stores (TBS) and balance in theoretical lactating women with low/moderate TBS.

METHODS

We studied 6 theoretical subjects with assigned values for TBS from 219-624 μmol. Using Simulation, Analysis, and Modeling software and a previously published compartmental model for whole-body VA metabolism, we simulated TBS over 6 mo of established lactation for each subject under 4 conditions: 1) prelactation VA intake was increased to maintain VA balance (LSS); 2) prelactation VA intake was maintained (NLSS); 3) VA intake was the same as 2) but a daily VA supplement (2.8 μmol/d) was added (NLSS+S); and 4) VA intake was as 1) and the daily VA supplement was included (LSS+S).

RESULTS

To compensate for the loss of VA via milk while VA balance was maintained (LSS) over 6 mo of lactation, VA intake had to increase by 0.8-1.87 μmol/d (n = 6) compared with NLSS. Over 6 mo of NLSS treatment, VA balance was negative (geometric mean, -0.77 μmol/d) compared with LSS, whereas balance was positive under NLSS+S and LSS+S conditions (0.75 and 1.5 μmol/d, respectively). For LSS, the proportion of total VA disposal was 37% via breastmilk, 32% from VA stores, and 32% from nonstorage tissues.

CONCLUSIONS

Adding a daily VA supplement (2.8 μmol/d) to the diet of lactating women with suboptimal VA intake may effectively counterbalance the negative VA balance resulting from the output of VA via breastmilk and thus benefit both mother and infant by maintaining or increasing VA stores and breastmilk VA concentration.

Establishment of Reference Range for Serum Concentration of Vitamin A and Vitamin E in Southern Sichuan Area of China

OBJECTIVE

To establish the reference range of serum concentration of vitamin A (VA) and vitamin E (VE) in Southern Sichuan area of China.

METHODS

From August 1, 2021, to May 31, 2023, 9482 blood tablets were received for the screening of VA and VE. The information was divided into four different age groups: ≤1 year old, 1< to ≤6 years, 6< to ≤17 years, and 17< to ≤59 years. In each age group, the four seasons were further subdivided into spring, summer, autumn, and winter, as well as male and female genders. The serum concentration of VA and VE was detected by liquid chromatography-tandem mass spectrometry (HPLC-MS), and the reference range was established for verification.

RESULTS

The concentration of VA and VE in 9482 cases showed skewed distribution. When comparing between different age groups, the serum concentration of VA and VE was statistically significant (p < 0.05). While comparing different seasons, the serum VA levels in different seasons were significantly different (p < 0.05) except in summer and autumn. There was statistical significance in VE level in different seasons (p < 0.05). And while comparing different genders, there was no statistical significance in VA concentration levels (p > 0.05). The VE concentration levels were statistically significant (p < 0.05). The established reference range was established and verified, and the results were in accordance with the standard.

CONCLUSION

The reference range of VA and VE should be set according to different ages, different seasons, and different genders.

Evaluating the relationship between the nutrient intake of lactating women and their breast milk nutritional profile: a systematic review and narrative synthesis

Maternal diet influences breast milk nutritional profile; however, it is unclear which nutrients and contaminants are particularly responsive to short- and long-term changes in maternal intake, and the impact of specific exclusion diets, such as vegan or vegetarian. This study systematically reviewed the literature on the effects of maternal nutrient intake, including exclusion diets, on both the nutrient and contaminant content of breast milk. The electronic databases, PubMed, CENTRAL, Web of Science and CINALH were systematically searched until 4 June 2023, with additionally searches of reference lists (PROSPERO, CRD42020221577). The quality of the studies was examined using Cochrane Risk of Bias tool and Newcastle-Ottawa scale. Eighty-eight studies (n 6577) met the search criteria. Due to high heterogeneity, meta-analysis was not possible. There was strong evidence of response to maternal intakes for DHA and EPA, vitamins A, E and K, iodine and Se in breast milk composition, some evidence of response for α-linolenic acid, B vitamins, vitamin C and D, ovalbumin, tyrosine and contaminants, and insufficient evidence to identify the effects arachidonic acid, Cu, Fe, Zn and choline. The paucity of evidence and high heterogeneity among studies reflects the need for more high-quality trials. However, this review identified the importance of maternal intake in the nutritional content of breast milk for a wide range of nutrients and supports the recommendation for supplementation of DHA and vitamin B12 for those on restrictive diets.

Association of vitamin A with gestational diabetes and thyroid disorders in pregnancy and their influence on maternal, fetal, and neonatal outcomes

Gestational diabetes mellitus (GDM) and thyroid disorders during pregnancy pose significant health concerns, impacting a substantial number of mothers globally. Globally, about 14% of pregnant women develop GDM, while thyroid disorders impact approximately 2%-3%. Both conditions contribute to adverse outcomes, including gestational hypertension, excessive fetal growth, and heightened perinatal morbidity. The central focus of this literature review is to examine the relationship between vitamin A, a crucial fat-soluble micronutrient in fetal development, and the occurrence of GDM and thyroid disorders during pregnancy. The primary research question investigates the association between vitamin A, GDM, and thyroid disorders, analyzing their combined impact on maternal, fetal, and neonatal outcomes. The review underscores the potential of vitamin A to modulate the risk and outcomes of GDM and thyroid disorders during gestation, emphasizing its role in GDM development and resolution and its influence on thyroid function in pregnancy.

Vitamin A-Mediated Birth Defects: A Narrative Review

Vitamin A deficiency (VAD) or excess in expectant mothers can result in fetal abnormalities such as night blindness, bone anomalies, or epithelial cell problems. In contrast, excessive vitamin A in pregnancy can precipitate fetal central nervous system deformities. During pregnancy, a pregnant woman should monitor her vitamin A intake ensuring she gets the recommended dosage, but also ensuring she doesn't exceed the recommended dosage, because either one can result in teratogenicity in the fetus. The widespread and unregulated use of multivitamins and supplements makes consuming doses greater than the recommended quantity more common in developed countries. While vitamin A excess is more common in developed countries, deficiency is most prevalent in developing countries. With proper maintenance, regulation, and education about VAD and excess, a pregnant mother can diminish potential harm to her fetus and potential teratogenic risks.

Vitamin A Concentration in Human Milk: A Meta-Analysis

Humans require vitamin A (VA). However, pooled VA data in human milk is uncommon internationally and offers little support for dietary reference intake (DRIs) revision of infants under 6 months. As a result, we conducted a literature review and a meta-analysis to study VA concentration in breast milk throughout lactation across seven databases by August 2021. Observational or intervention studies involving nursing mothers between the ages of 18 and 45, with no recognized health concerns and who had full-term infants under 48 months were included. Studies in which retinol concentration was expressed as a mass concentration on a volume basis and determined using high-, ultra-, or ultra-fast performance liquid chromatography (HPLC, UPLC, or UFLC) were chosen. Finally, 76 papers involving 9171 samples published between 1985 and 2021 qualified for quantitative synthesis. Results from the random-effects model showed that the VA concentration of healthy term human milk decreased significantly as lactation progressed. VA (µg/L) with 95% CI at the colostrum, transitional, early mature and late mature stages being 920.7 (744.5, 1095.8), 523.7 (313.7, 733.6), 402.4 (342.5, 462.3) and 254.7 (223.7, 285.7), respectively (X2 = 71.36, p < 0.01). Subgroup analysis revealed no significant differences identified in VA concentration (µg/L) between Chinese and non-Chinese samples at each stage, being 1039.1 vs. 895.8 (p = 0.64), 505.7 vs. 542.2(p = 0.88), 408.4 vs. 401.2 (p = 0.92), 240.0 vs. 259.3 (p = 0.41). The findings have significant implications for the revision of DRIs for infants under six months.

Breast Milk Retinol Levels after Vitamin A Supplementation at Different Postpartum Amounts and Intervals

Maternal vitamin A (VA) supplementation in risk areas for Vitamin A deficiency (VAD) was launched to improve the level of this nutrient in nursing mothers and in their breast milk. This longitudinal and randomized study aimed to evaluate the levels of retinol in breast milk after supplementation with VA in varying amounts (200,000 IU or 400,000 IU) and different postpartum intervals. Women were distributed into four intervention groups and given a single 200,000 IU postnatal dosage of VA at time 0 h (postnatal morning) (G200 0H); a single 200,000 IU dosage of VA in week four (G200 4W); 200,000 IU of VA at time 0 h + 200,000 IU of VA 24 h after the first supplementation (G400 24H); and 200,000 IU of VA at time 0 h + 200,000 IU of VA one week after the first supplementation (G400 1W). Breast milk samples were collected over a 12-week period (0 h, 24 h and 1, 4, 12 weeks post-natal). Retinol levels were determined by high-performance liquid chromatography. The Generalized Estimated Equation (GEE) assessed the different retinol levels. The G200 (0H), G400 (24H), and G400 (1W) groups presented higher retinol levels at 24 h than the G200 (4W) group (p < 0.001). The retinol levels of all groups were similar at times 1, 4 and 12 weeks after delivery (p > 0.05). Maternal VA supplementation increased retinol levels in the colostrum. Different supplementation dosages or postpartum administration times did not result in added benefit to retinol levels in mature breast milk.