Undernutrition and growth in the developing world

Alternate-day fasting delays pubertal development in normal-weight mice but prevents high-fat diet-induced obesity and precocious puberty

BACKGROUND/OBJECTIVES

Childhood obesity, particularly in girls, is linked to early puberty onset, heightening risks for adult-onset diseases. Addressing childhood obesity and precocious puberty is vital to mitigate societal burdens. Despite existing costly and invasive medical interventions, introducing lifestyle-based alternatives is essential. Our study investigates alternate-day fasting's (ADF) impact on pubertal development in normal-weight and high-fat diet (HFD)-induced obese female mice.

METHODS

Four groups of female mice were utilized, with dams initially fed control chow during and before pregnancy. Post-parturition, two groups continued on control chow, while two switched to an HFD. Offspring diets mirrored maternal exposure. One control and one HFD group were subjected to ADF. Morphometry and hormone analyses at various time points were performed.

RESULTS

Our findings demonstrate that ADF in normal-weight mice led to reduced body length, weight, uterine, and ovarian weights, accompanied by delayed puberty and lower levels of sex hormones and growth hormone (GH). Remarkably, GH treatment effectively prevented ADF-induced growth reduction but did not prevent delayed puberty. Conversely, an HFD increased body length, induced obesity and precocious puberty, and altered sex hormones and leptin levels, which were counteracted by ADF regimen. Our data indicate ADF's potential in managing childhood obesity and precocious puberty.

CONCLUSIONS

ADF reduced GH and sex hormone levels, contributing to reduced growth and delayed puberty, respectively. Therefore, parents of normal-weight children should be cautious about prolonged overnight fasting. ADF prevented HFD-induced obesity and precocious puberty, offering an alternative to medical approaches; nevertheless, further studies are needed for translation into clinical practice.

Lysine-rich rice partially enhanced the growth and development of skeletal system with better skeletal microarchitecture in young rats

Rice is the primary staple food for half of the world's population but is low in lysine content. Previously, we developed transgenic rice with enhanced free lysine content in rice seeds (lysine-rich rice), which was shown safe for consumption and improved the growth in rats. However, the effects of lysine-rich rice on skeletal growth and development remained unknown. In this study, we hypothesized that lysine-rich rice improved skeletal growth and development in weaning rats. Male weaning Sprague-Dawley rats received lysine-rich rice (HFL) diet, wild-type rice (WT) diet, or wild-type rice with various contents of lysine supplementation diet for 70 days. Bone microarchitectures were examined by microcomputed tomography, bone strength was investigated by mechanical test, and dynamics of bone growth were examined by histomorphometric analysis. In addition, we explored the molecular mechanism of lysine and skeletal growth through biochemical testing of growth hormone, bone turnover marker, and amino acid content of rat serum analysis, as well as in a cell culture system. Results indicated that the HFL diet improved rats' bone growth, strength, and microarchitecture compared with the WT diet group. In addition, the HFL diet increased the serum essential amino acids, growth hormone (insulin-like growth factor-1), and bone formation marker concentrations. The cell culture model showed that lysine deficiency reduced insulin-like growth factor-1 and Osterix expression, Akt/mammalian target of rapamycin signaling, and matrix mineralization, and inhibited osteoblast differentiation associated with bone growth. Our findings showed that lysine-rich rice improved skeletal growth and development in weaning rats. A further increase of rice lysine content is highly desirable to fully optimize bone growth and development.

Nutrition in school-age children: a rationale for revisiting priorities

Middle childhood and early adolescence have received disproportionately low levels of scientific attention relative to other life stages, especially as related to nutrition and health. This is partly due to the justified emphasis on the first 1000 days of life, and the idea that early deficits and consequences may not be fully reversible. In addition, these stages of life may superficially appear less "eventful" than infancy or late adolescence. Finally, there has been historical ambiguity and inconsistency in terminology, depending on whether viewing "childhood" through physiologic, social, legal, or other lenses. Nevertheless, this age bracket, which encompasses most of the primary education and basic schooling years for most individuals, is marked by significant changes, inflection points, and sexually driven divergence in somatic and brain growth and development trajectories. These constitute transformative changes, and thus middle childhood and early adolescence represents a major and last opportunity to influence long-term health and productivity. This review highlights the specificities of growth and development in school age, with a focus on middle childhood and early adolescence (5 years-15 years of age, for the purposes of this review), the role of nutrition, the short- and long-term consequences of inadequate nutrition, and the current global status of nutrition in this age group. Adequate attention and emphasis on nutrition in the school-age years is critical: (a) for maintaining an adequate course of somatic and cognitive development, (b) for taking advantage of this last major opportunity to correct deficits of undernutrition and "catch-up" to normal life course development, and (c) for addressing the nutritional inadequacies and mitigating the longer-term consequences of overnutrition. This review summarizes and provides a rationale for prioritizing nutrition in school-age children, and for the need to revisit priorities and focus on this part of the life cycle to maximize individuals' potential and their contribution to society.

Food addiction symptoms and metabolic changes in children and adolescents with the double burden of malnutrition

The double burden of malnutrition (DBM) has been described in many low-/middle-income countries. We investigated food addiction, thyroid hormones, leptin, the lipid/glucose profile and body composition in DBM children/adolescents. Subjects were allocated into groups according to nutritional status: control (C, n 28), weight excess (WE, n 23) and DBM (WE plus mild stunting, n 22). Both the DBM and WE groups showed higher mean insulin concentrations than the control (DBM = 57·95 (95 % CI 47·88, 70·14) pmol/l, WE = 74·41 (95 % CI 61·72, 89·80) pmol/l, C = 40·03 (95 % CI 34·04, 47·83) pmol/l, P < 0·001). WE and DBM showed more food addiction symptoms than the control (3·11 (95 % CI 2·33, 3·89), 3·41 (95 % CI 2·61, 4·20) and 1·66 (95 % CI 0·95, 2·37)). In DBM individuals, addiction symptoms were correlated with higher body fat and higher insulin and leptin levels. These data provide preliminary evidence consistent with the suggestion that DBM individuals have a persistent desire to eat, but further studies are required to confirm these results in a larger study. These hormonal changes and high body fat contribute to the development of diabetes in long term.