Dairy and milk consumption and child growth: Is BMI involved? An analysis of NHANES 1999-2004

A review of dairy food intake for improving health among black infants, toddlers, and young children in the US

Adequate nutrition is paramount for proper growth and musculoskeletal, neurocognitive, and immunological development in infants, toddlers, and young children. Among breastfeeding mother-child dyads, this critical window of development, is impacted by both maternal and offspring dietary patterns. For mothers, their dietary patterns impact not only their own health and well-being, but also the nutrition of their breast milk - which is recommended as the sole source of food for the first 6 months of their infant's life, and as a complementary source of nutrition until at least 2 years of age. For infants and toddlers, the breast milk, formulas, and first foods they consume can have both short-term and long-term effects on their health and well-being - with important impacts on their taste perception, microbiome composition, and immune function. According to dietary intake data in the US, infants and young children meet a greater number of nutrient requirements than older children and adults, yet numerous disparities among socially disadvantaged racial/ethnic groups still provide significant challenges to achieving adequate nutrition during these early life stages. For example, Black children are at greater risk for disparities in breastfeeding, age-inappropriate complementary feeding patterns, nutrient inadequacies, food insecurity, and obesity relative to most other racial/ethnic groups in the US. For infants who do not receive adequate breast milk, which includes a disproportionate number of Black infants, dairy-based infant formulas are considered the next best option for meeting nutritional needs. Fermented dairy foods (e.g., yogurt, cheese) can serve as ideal first foods for complementary feeding, and cow's milk is recommended for introduction during the transitional feeding period to help meet the nutrient demands during this phase of rapid growth and development. Low dairy intake may put children at risk for multiple nutrient inadequacies and health disparities - some of which may have lifelong consequences on physical and mental health. A burgeoning body of research shows that in addition to breast milk, cow's milk and other dairy foods may play critical roles in supporting physical growth, neurodevelopment, immune function, and a healthy gut microbiome in early life. However, most of this research so far has been conducted in White populations and can only be extrapolated to Black infants, toddlers, and young children. Therefore, to better understand and support the health and development of this population, greater research and education efforts on the role of milk and dairy products are urgently needed. This review presents the current evidence on health disparities faced by Black children in the US from birth to four years of age, and the role that dairy foods can play in supporting the normal growth and development of this vulnerable population.

Poor Quality Diets Characterized by Low-Nutrient Density Foods Observed in One-Quarter of 2-Year-Olds in a High Resource Setting

BACKGROUND

Young children have high nutritional requirements relative to their body size, making healthy diets critical for normal growth and development.

OBJECTIVE

We aimed to integrate analysis of dietary patterns among 2-y-old children with indicators of dietary quality, micronutrient status, and body weight status.

METHODS

Data from the 2-y follow-up of the Cork BASELINE Birth Cohort included dietary assessment using a 2-d weighed food diary, vitamin D and iron status biomarkers, and anthropometry (n = 468). K-means cluster analysis identified predominant dietary patterns based on energy contributions and associations with nutrient intakes and status and body weight were investigated.

RESULTS

Four dietary patterns emerged: "Cows' milk" (unmodified cows' milk: 32% of total energy (TE)); "Traditional" (wholemeal breads, butter, fresh meat, fruit); "Low Nutrient Density (LND) foods" (confectionary, processed meat, convenience foods) and "Formula" (young child formula: 23%TE). The LND pattern was associated with excessive free sugar intake (14%TE) and salt intake (153% of daily limit). No differences in patterns of overweight were observed between the 4 groups; however, the LND group had 3-fold higher odds of being underweight [aOR (95% CI): 3.2 (1.2, 8.5)]. Children consuming >400ml/d of cows' milk or formula exhibited lower dietary variety, fewer family-type meals, and continued use of feeding bottles (75% and 81%, respectively, vs. 35-37% in the other groups).

CONCLUSIONS

Unhealthy eating habits are common among young children. Dietary guidance to support families to provide healthy diets needs to maintain currency with eating habits and focus on food choices for meals, snacks, and beverages.

What can Mendelian randomization contribute to biological anthropology?

Uncovering causal relationships between exposures and outcomes can be difficult in observational studies because of the potential for confounding and reverse causation to produce biased estimates. Conversely, randomized controlled trials (RCTs) provide the strongest evidence for causality but they are not always feasible. Mendelian randomization (MR) is a method that aims to strengthen causal inference using genetic variants as proxies or instrumental variables (IVs) for exposures, to overcome the above-mentioned biases. Since allele segregation occurs at random from parents to offspring, and alleles for a trait assort independently from those for other traits, MR studies have frequently been compared to "natural" RCTs. In biological anthropology (BA) relationships between variables of interest are usually evaluated using observational data, often remaining descriptive, and other approaches to causal inference have seldom been implemented. Here, we propose the use of MR to investigate cause and effect relationships in BA studies and provide examples to show how that can be done across areas of BA relevance, such as adaptation to the environment, nutrition and life history theory. While we consider MR a useful addition to the biological anthropologist's toolbox, we advocate the adoption of a wide range of methods, affected by different types of biases, in order to better answer the important causal questions for the discipline.

Effect of milk and mustard oil consumption: A case study on youth in Delhi-NCR

Background: The diet is a major factor affecting the Body Mass Index (BMI) of an individual. BMI has long been the standard for measuring health and its normal range (18.5-24.9, according to the World Health Organization) is considered to be crucial for maintenance of proper health and to prevent various lifestyle disorders which are considered to have either direct or indirect effects on physical and mental well-being of our youth. Aim: To investigate the correlation between diet patterns and BMI, overall stamina and fatigue levels in the youth population residing in Delhi-NCR region of India. Methods: An online survey was conducted using a carefully designed Google form and the respondents were asked to give details about the basic health parameters and dietary lifestyle. Results: 67% of the respondents who consumed milk were found to have an ideal BMI. 64% of the respondents who consumed mustard oil as their predominant dietary fat showed normal BMI and more than 80% showed lower fatigue levels. Conclusion: Milk and mustard oil consumption is important for maintenance of an ideal BMI. Awareness should be created in the youth to have them as part of their daily diet.

The Role of Cow's Milk Consumption in Breast Cancer Initiation and Progression

PURPOSE OF REVIEW

This review evaluates cow milk's impact on breast carcinogenesis by linking recent epidemiological evidence and new insights into the molecular signaling of milk and its constituents in breast cancer (BCa) pathogenesis.

RECENT FINDINGS

Recent prospective cohort studies support the association between cow's milk consumption and the risk of estrogen receptor-α-positive (ER+) BCa. Milk is a complex biological fluid that increases systemic insulin-like growth factor 1 (IGF-1), insulin and estrogen signaling, and interacting hormonal promoters of BCa. Further potential oncogenic components of commercial milk include exosomal microRNAs (miR-148a-3p, miR-21-5p), bovine meat and milk factors, aflatoxin M1, bisphenol A, pesticides, and micro- and nanoplastics. Individuals with BRCA1 loss-of-function mutations and FTO and IGF1 gain-of-function polymorphisms enhancing IGF-1/mTORC1 signaling may be at increased risk for milk-induced ER+ BCa. Recent prospective epidemiological and pathobiochemical studies identify commercial milk consumption as a critical risk factor of ER+ BCa. Large meta-analyses gathering individuals of different ethnic origins with milk derived from dairy cows of varying genetic backgrounds and diverse feeding procedures as well as missing data on thermal processing of milk (pasteurization versus ultra-heat treatment) make multi-national meta-analyses unsuitable for BCa risk estimations in susceptible populations. Future studies are required that consider all vulnerable periods of breast carcinogenesis to cow's milk exposure, beginning during the perinatal period and puberty, since these are the most critical periods of mammary gland morphogenesis. Notwithstanding the need for better studies including detailed information on milk processing and vulnerable periods of human breast carcinogenesis, the available evidence suggests that dietary guidelines on milk consumption may have to be reconsidered.

The Relationship between Fluid Milk, Water, and 100% Juice and Health Outcomes among Children and Adolescents

Beverages can provide improved nutrient intake and hydration, but also pose concerns related to overnutrition or contamination for children and adolescents who are in a time of critical growth. This narrative review aims to understand the impact of milk, 100% juice, and water consumption on health-related outcomes in youth. The literature review conducted used PubMed, Web of Science, and CABI global. Forty-five research articles met the quality criteria and were included. Health organization and governmental resources were also reviewed to identify current intake and consumption recommendations. All beverages in this review were associated with a variety of desirable and undesirable findings that spanned over 40 different health outcomes. Most studies that assessed milk lacked clear distinction between milk type (flavored vs. unflavored) or fat percentage, making it difficult to understand the impact of milk consumption. The relationship between milk intake and anthropometric-related outcomes were mixed within and across studies. Water was consistently associated with better hydration, while 100% juice and flavored milk intake was associated with more desirable dietary patterns or nutrients that children are currently not consuming adequate amounts of. The implications of these findings were discussed in the context of the National School Lunch Program (NSLP), while considering the impact of issues such as contaminated water and lactose intolerance. This review suggests that water may be an optimal default beverage option in the NSLP to promote hydration and accommodate beverage preferences for those with lactose intolerance.

A critical biocultural approach to early growth in the United States

OBJECTIVES

A critical biocultural anthropology seeks to link perspectives from social theory and ethnography to human biology. In the United States (U.S.), multiple forms of structural inequalities affect early growth, including racism and poverty. The goal of this paper is to test the effects of social inequalities on birth weight and later height in the U.S. National Health and Nutrition Survey (NHANES), and to contextualize potential pathways of embodiment that link social structure and biology.

METHODS

This study used data from 8392 children ages 0-5 years from the 2005 to 2016 NHANES. Reported birth weight and measured length/height (converted to height-for-age z-scores) were used as outcome variables, while various measures of socioeconomic status and the NHANES-defined race and ethnicity categories were operationalized as social variables. Structural equation modeling (SEM) was chosen to represent the data.

RESULTS

The final model represented an excellent fit to the data. Higher birth weights were associated with higher height-for-age z-scores. The Black racial category was associated with lower birth weight and higher height-for-age z-score, while the "Other" racial category was also associated with lower birth weight. The socioeconomic status factor variable was significantly associated with birth weight and height-for-age z-scores. There were also multiple indirect effects of social variables on height-for-age z-scores mediated via their effects on birth weight.

CONCLUSIONS

Inequalities in race and socioeconomic status persist in birth weight and early childhood stature in the U.S. These findings can be contextualized by a critical biocultural anthropology that integrates lived experiences and pathways of embodiment.

Sugar-sweetened beverage consumption and overweight and obesity in adolescents in Ho Chi Minh City, Vietnam: a population-based analysis

BACKGROUND

The aim of this research was to describe the patterns of consumption of multiple sugar-sweetened beverages (including modern and traditional ones) among adolescents in Ho Chi Minh City and to identify a possible relationship between this consumption and overweight, obesity, and other factors.

METHODS

A secondary analysis from a cross-sectional study of 11-15-year-old students from 31 junior high schools across Ho Chi Minh City was used. We measured the students' anthropometric status and assessed beverage consumption using a validated Food Frequency Questionnaire. Multivariate logistic regression models were used to identify the association between the consumption of sugar-sweetened beverages, obesity and other factors.

RESULTS

The sugar-sweetened beverages (SSB) ranged widely from modern soft drinks and powdered drinks to traditional sugar-added fruit and leaf juices, and milk-based drinks. These beverages were very popular among 2,660 participants with 36% consuming at least one variety daily. Factors positively associated with sugar-sweetened beverage consumption included a higher level of physical activity, higher consumption of fast foods, and daily fruit and vegetable consumption. We found a negative association between milk-based SSBs and the overweight and obesity status of the students, i.e. every kcal more of fresh milk with sugar and condensed milk can reduce an obesity odd of 0.005 (95% CI [0.002-0.008], p < 0.001) and 0.004 (95% CI [0.002-0.010], p = 0.044) consecutively. None of the other SSBs was significantly related to adolescent overweight and obesity.

CONCLUSIONS

Milk-based drinks potentially protect adolescents against overweight and obesity. Further research to assess this protection is needed.

Is High Milk Intake Good for Children's Health? A National Population-Based Observational Cohort Study

Milk is widely considered as a beneficial product for growing children. This study was designed to describe the milk consumption status of Korean children aged 30–36 months and to investigate its association with the risk of obesity and iron deficiency anemia (IDA). This nationwide administrative study used data from the Korean national health insurance system and child health screening examinations for children born in 2008 and 2009. In total, 425,583 children were included, and they were divided into three groups based on daily milk consumption: low milk group (do not drink or drink <200 mL milk per day, n = 139,659), reference group (drink 200–499 mL milk per day, n = 255,670), and high milk group (drink ≥500 mL milk per day, n = 30,254). After adjusting variable confounding factors, the consumption of a large amount of milk of ≥500 mL per day at the age of 30–36 months was associated with an increased risk of obesity at the age of 42–72 months and IDA after the age of 30 months. These results may provide partial evidence for dietary guidelines for milk consumption in children that are conducive to health.

The effect of milk and rapeseed protein on growth factors in 7-8 year-old healthy children - A randomized controlled trial

OBJECTIVE

Milk protein may stimulate linear growth through insulin-like growth factor-1 (IGF-1). However, the effect of plant proteins on growth factors is largely unknown. This study assesses the effect of combinations of milk and rapeseed protein versus milk protein alone on growth factors in children.

DESIGN

An exploratory 3-armed randomized, double-blind, controlled trial was conducted in 129 healthy 7-8 year-old Danish children. Children received 35 g milk and rapeseed protein (ratio 54:46 or 30:70) or 35 g milk protein per day for 4 weeks. The primary outcome was difference in IGF-1 changes between intervention groups after 4 weeks. Secondary outcomes included changes in IGF-1 after 1 week and changes in insulin-like growth factor binding protein-3 (IGFBP-3), IGF-1/IGFBP-3, insulin, height, weight and body composition after 1 and 4 weeks. Results were analysed by multiple linear mixed-effect models.

RESULTS

There were no differences in changes of plasma IGF-1, insulin-like growth factor binding protein-3 (IGFBP-3), IGF-1/IGFBP-3 ratio or insulin between groups after 1 or 4 weeks based on 89 complete cases (P > 0.10). IGF-1 increased by 13.7 (95% CI 9.7;17.7) ng/mL and 18.0 (14.0;22.0) ng/mL from baseline to week 1 and 4, respectively, a 16% increase during the intervention. Similarly, insulin increased by 31% (14; 50) and 33% (16; 53) from baseline to week 1 and 4. Fat-free mass index (FFMI) increments were higher with milk alone than rapeseed blends (P < 0.05), coinciding with a trend towards a lower height increment. Body mass index increased within all groups (P < 0.05), mainly due to an increase in FFMI (P < 0.01).

CONCLUSION

There were no differences in changes of growth factors between the combinations of milk and rapeseed protein and milk protein alone in healthy, well-nourished children with a habitual intake of milk. Within groups, growth factors increased considerably. Future studies are needed to investigate how intakes of plant and animal proteins affect childhood growth.

Obesity determinants among Malaysian 12-year old school adolescents: findings from the HAT study

BACKGROUND

Childhood obesity has been associated with increased odds of adult obesity and co-morbidities in later life. Finding the key determinants may help in designing the most appropriate and effective interventions to prevent obesity. This study aimed to identify the determinants of obesity among school adolescents in a sub-urban state of Malaysia.

METHODS

This cross-sectional study involved 1,404 school adolescents aged 12 years (46% boys and 54% girls). Socio-demographic, dietary and physical activity data were collected using questionnaires whilst body weight and height were measured and body mass index was classified based on WHO BMI-for-age Z-scores cut-off.

RESULTS

A multivariable linear regression model showed that BMI z-score was positively associated with parents' BMI (P<0.001), birth weight (P=0.003), and serving size of milk and dairy products (P=0.036) whilst inversely associated with household size (P=0.022). Overall, 13.1% of the variances in BMI Z-scores were explained by parents' BMI, birth weight, servings of milk and dairy products and household size.

CONCLUSION

This study found important determinants of body weight status among adolescents mainly associated with family and home environmental factor. This evidence could help to form the effective and tailored strategies at the earliest stage to prevent obesity in this population.

[Health risks related to milk consumption: a critical evaluation from the medical perspective]

BACKGROUND

Recent epidemiological studies associate the consumption of non-fermented cow's milk, but not fermented milk products, with an increased risk of diseases of civilization.

OBJECTIVES

Presentation of epidemiological and pathophysiological data on health risks associated with milk consumption.

METHOD

Selective PubMed surveys between 2005-2020 considering epidemiological studies which clearly differentiate between non-fermented versus fermented milk and its potential health risks.

RESULTS

Epidemiological studies confirm a correlation between milk consumption and birthweight, linear growth during puberty, acne vulgaris, type 2 diabetes mellitus, prostate cancer, breast cancer, hepatocellular carcinoma, non-Hodgkin lymphoma, Parkinson's disease and over-all mortality. In comparison to milk consumption, the intake of fermented milk/milk products exhibits neutral to beneficial health effects, which are explained by attenuated mTORC1 signaling due to bacterial fermentation of milk.

CONCLUSIONS

Long-term persistent consumption of non-fermented milk, but not fermented milk/milk products, might increase the risk of diseases of civilization. The avoidance of milk, especially pasteurized fresh milk, may enhance the prevention and reduce the recurrence of common Western diseases of civilization.

Lifetime Impact of Cow's Milk on Overactivation of mTORC1: From Fetal to Childhood Overgrowth, Acne, Diabetes, Cancers, and Neurodegeneration

The consumption of cow's milk is a part of the basic nutritional habits of Western industrialized countries. Recent epidemiological studies associate the intake of cow's milk with an increased risk of diseases, which are associated with overactivated mechanistic target of rapamycin complex 1 (mTORC1) signaling. This review presents current epidemiological and translational evidence linking milk consumption to the regulation of mTORC1, the master-switch for eukaryotic cell growth. Epidemiological studies confirm a correlation between cow's milk consumption and birthweight, body mass index, onset of menarche, linear growth during childhood, acne vulgaris, type 2 diabetes mellitus, prostate cancer, breast cancer, hepatocellular carcinoma, diffuse large B-cell lymphoma, neurodegenerative diseases, and all-cause mortality. Thus, long-term persistent consumption of cow's milk increases the risk of mTORC1-driven diseases of civilization. Milk is a highly conserved, lactation genome-controlled signaling system that functions as a maternal-neonatal relay for optimized species-specific activation of mTORC1, the nexus for regulation of eukaryotic cell growth, and control of autophagy. A deeper understanding of milk´s impact on mTORC1 signaling is of critical importance for the prevention of common diseases of civilization.

Evidence for a causal association between milk intake and cardiometabolic disease outcomes using a two-sample Mendelian Randomization analysis in up to 1,904,220 individuals

BACKGROUND

High milk intake has been associated with cardio-metabolic risk. We conducted a Mendelian Randomization (MR) study to obtain evidence for the causal relationship between milk consumption and cardio-metabolic traits using the lactase persistence (LCT-13910 C > T, rs4988235) variant as an instrumental variable.

METHODS

We tested the association of LCT genotype with milk consumption (for validation) and with cardio-metabolic traits (for a possible causal association) in a meta-analysis of the data from three large-scale population-based studies (1958 British Birth Cohort, Health and Retirement study, and UK Biobank) with up to 417,236 participants and using summary statistics from consortia meta-analyses on intermediate traits (N = 123,665-697,307) and extended to cover disease endpoints (N = 86,995-149,821).

RESULTS

In the UK Biobank, carriers of 'T' allele of LCT variant were more likely to consume milk (P = 7.02 × 10^-14). In meta-analysis including UK Biobank, the 1958BC, the HRS, and consortia-based studies, under an additive model, 'T' allele was associated with higher body mass index (BMI) (P_{meta-analysis} = 4.68 × 10^-12) and lower total cholesterol (TC) (P = 2.40 × 10^-36), low-density lipoprotein cholesterol (LDL-C) (P = 2.08 × 10^-26) and high-density lipoprotein cholesterol (HDL-C) (P = 9.40 × 10^-13). In consortia meta-analyses, 'T' allele was associated with a lower risk of coronary artery disease (OR:0.86, 95% CI:0.75-0.99) but not with type 2 diabetes (OR:1.06, 95% CI:0.97-1.16). Furthermore, the two-sample MR analysis showed a causal association between genetically instrumented milk intake and higher BMI (P = 3.60 × 10^-5) and body fat (total body fat, leg fat, arm fat and trunk fat; P < 1.37 × 10^-6) and lower LDL-C (P = 3.60 × 10^-6), TC (P = 1.90 × 10^-6) and HDL-C (P = 3.00 × 10^-5).

CONCLUSIONS

Our large-scale MR study provides genetic evidence for the association of milk consumption with higher BMI but lower serum cholesterol levels. These data suggest no need to limit milk intakes with respect to cardiovascular disease risk, with the suggested benefits requiring confirmation in further studies.

Growth and Development of Preschool Children (12-60 Months): A Review of the Effect of Dairy Intake

Undernutrition in young children is a global health issue. The ability to meet energy and nutrient needs during this critical stage of development is necessary, not only to achieve physical and mental potential but also socio-economic achievement later in life. Given ongoing discussions regarding optimization of dietary patterns to support achievement of the Sustainable Development Goals established by the United Nations, it is important to identify foods/food groups that have shown efficacy in reducing the negative impacts of undernutrition in young children. This narrative review addresses the impact of dairy intake, with a focus on linear growth, cognitive development and weight gain in early childhood (12-60 months). The impact of country economic status is also examined, to help elucidate regional specific recommendations and/or future research needs. Overall, the body of research addressing this age group is somewhat limited. Based on the data available, there is a positive association between dairy intake and linear growth. The impact of milk or dairy products on cognitive development is less clear due to a lack of evidence and is a gap in the literature that should be addressed. Regarding the impact on body weight, the majority of evidence suggests there is either no association or an inverse association between milk intake by preschool children on overweight and obesity later in life. This evidence is exclusively in high income countries, however, so additional work in lower income countries may be warranted.

Perspective: Chaos in a Bottle-A Critical Evaluation of Beverage Categorization in Nutrition Research

Beverage consumption is an important contributor to total daily calorie intake among children and adolescents. While associations between excess calories from beverages and development of obesity are well established, a standardized approach for beverage categorization does not exist. As a result, there is marked heterogeneity in assessment and categorization of beverage intake across studies. The purpose of this article is to critically review beverage categorization in recent (published since 2010) observational studies that evaluated beverage intake in relation to weight/adiposity in US youth, and to put forth an initial proposal for a standardized beverage classification system. Standardized beverage classification is critical to ensure transparency in nutrition science research and facilitate comparison of findings across studies. A systematic literature search identified 37 eligible studies, across which beverage categorization varied considerably. The most heterogeneity was observed for categorization of "sugar-sweetened beverages" and the greatest consistency was observed for categorization of 100% juices. This review provides an evidence-based starting point for urgently needed, collaborative work to determine priorities for beverage categorization and leverage existing standards of identity in order to create and disseminate a standardized beverage classification system. A standardized approach will inform meaningful assessment of beverage consumption in research studies and facilitate impactful translation of research findings into public health nutrition policy.

Association between milk intake and childhood growth: results from a nationwide cross-sectional survey

PURPOSE

The literature is inconsistent regarding milk intake and physical growth. This study aims to evaluate the association of milk intake with body height and weight in a nationally representative sample of Chinese children.

METHODS

A total of 41,439 children ages 6-17 were recruited from 30 provinces in mainland China in 2013-2016 using a multistage stratified cluster sampling approach. Milk intake information was collected using a questionnaire aided with standard containers. Weight and height were measured using a standard physician beam scale with a height rod. Milk intake was categorized into no-, low-, and high-intake groups based on the intake rate, and weight status into normal, overweight, and obese groups based on the body-mass-index (BMI). Associations between height/weight status and milk intake were evaluated using multivariate weighted linear and logistic regression models.

RESULTS

Chinese children had low milk intake: 1/5 of children did not drink milk, and those drinking milk had a median intake of 100 ml/month. The low- and high-intake groups were 0.83 cm (95% confidence interval: 0.00, 1.68 cm) and 1.26 cm (0.34, 2.19 cm) taller than the no-intake group for girls, respectively, after adjusting for confounding factors. Boys with high milk intake had lower BMI (-0.56, 95% CI: -1.00, -0.12 kg/m²) and risk of obesity (OR = 0.67, 95% CI: 0.46, 0.97) than those without milk intake.

CONCLUSIONS

This study revealed the association of increased milk intake with increased body height and lowered obesity risk among Chinese children. Given the cross-sectional nature of the study and the possibility of residual confounding, further research is warranted to uncover the role of milk intake in promoting children's growth.

Circulating Insulin-Like Growth Factor-1 Is Positively Associated with Growth and Cognition in 6- to 9-Year-Old Schoolchildren from Ghana

BACKGROUND

Milk intake stimulates linear growth and improves cognition in children from low-income countries. These effects may be mediated through insulin-like growth factor-1 (IGF-1).

OBJECTIVE

The objective was to assess the effect of milk supplement on circulating IGF-1 and to assess IGF-1 as a correlate of growth and cognition in children.

METHODS

Secondary data on blood spot IGF-1 from a randomized, double-blind, controlled trial in 6-9-y-old children from rural Ghana were analyzed. Intervention groups received porridge with non-energy-balanced supplements: 8.8 g milk protein/d, 100 kcal/d (Milk8); 4.4 g milk and 4.4 g rice protein/d, 100 kcal/d (Milk/rice); 4.4 g milk protein/d, 48 kcal/d (Milk4); or a control (no protein, 10 kcal/d). IGF-1, length, body composition, and Cambridge Neuropsychological Test Automated Battery (CANTAB) were measured at 3.5 or 8.5 mo. Linear regressions were used to assess the effect of milk interventions on IGF-1 and IGF-1 as a correlate of growth and cognition.

RESULTS

The increase in IGF-1 was 15.3 (95% CI: 3.3, 27.3) ng/mL higher in children receiving Milk8 compared with the control. The IGF-1 increases in the isonitrogenous, isoenergetic Milk/rice or the Milk4 groups were not different from the control (P ≥ 0.49). The increase in IGF-1 was associated with improvements in 4 out of 5 CANTAB domains. The strongest associations included reductions in "mean correct latency" from Pattern Recognition Memory and "pre-extradimensional (pre-ED) shift errors" from Intra/Extradimensional Set Shift (P ≤ 0.005). In addition, change in IGF-1 was positively associated with changes in height, weight, and fat-free mass (P ≤ 0.001).

CONCLUSIONS

Intake of skimmed milk powder corresponding to one, but not half a glass of milk on school days stimulates IGF-1 in 6-9-y-old Ghanian children. IGF-1 seems to mediate the effect of milk intake on growth and cognition. The association between IGF-1 and cognition in relation to milk intake is novel and opens possibilities for dietary interventions to improve cognition.

A biocultural examination of home food production and child growth in highland Peru

OBJECTIVES

Chronic malnutrition remains a persistent global health issue. This mixed methods investigation in rural Peru examines the role of home food production (HFP) in reducing child malnutrition by testing the following hypotheses: (a) higher HFP will be associated with higher infant z-scores than those with less HFP and (b) infants with higher HFP will exhibit improved longitudinal growth outcomes across 6 months.

METHODS

Ethnographic methods include semi-structured interviews and participant observation. A household survey and anthropometric data were collected twice, from 86 infants under of 24 months old. A HFP index (HFI) was generated based on reports of animals for meat consumption, eggs, milk, and agricultural products for home consumption. Kruskal-Wallis tests were used to examine patterns of HFI and infant anthropometrics. Multivariate regressions were used to examine the relationships between HFP and infant height for age (HAZ), weight for age (WAZ), and triceps skinfold for age (TSAZ) in both rounds and 6-month change between rounds (6MΔ).

RESULTS

There were no relationships between HFI and infant z-scores in round one, however, HFI was significantly positively related to HAZ (B = 0.091, P < .039) in round two and with 6MΔ in HAZ (B = 0.09, P < .047). HFI did not predict WAZ or TSAZ in either round.

CONCLUSIONS

HFP represents an important influence of infant growth in Nuñoa, likely through nutritional improvement due to increased availability of animal-sourced foods and through contribution to household economy and maternal empowerment.

Milk exosomal miRNAs: potential drivers of AMPK-to-mTORC1 switching in β-cell de-differentiation of type 2 diabetes mellitus

Type 2 diabetes mellitus (T2DM) steadily increases in prevalence since the 1950's, the period of widespread distribution of refrigerated pasteurized cow's milk. Whereas breastfeeding protects against the development of T2DM in later life, accumulating epidemiological evidence underlines the role of cow's milk consumption in T2DM. Recent studies in rodent models demonstrate that during the breastfeeding period pancreatic β-cells are metabolically immature and preferentially proliferate by activation of mechanistic target of rapamycin complex 1 (mTORC1) and suppression of AMP-activated protein kinase (AMPK). Weaning determines a metabolic switch of β-cells from a proliferating, immature phenotype with low insulin secretion to a differentiated mature phenotype with glucose-stimulated insulin secretion, less proliferation, reduced mTORC1- but increased AMPK activity. Translational evidence presented in this perspective implies for the first time that termination of milk miRNA transfer is the driver of this metabolic switch. miRNA-148a is a key inhibitor of AMPK and phosphatase and tensin homolog, crucial suppressors of mTORC1. β-Cells of diabetic patients return to the postnatal phenotype with high mTORC1 and low AMPK activity, explained by continuous transfer of bovine milk miRNAs to the human milk consumer. Bovine milk miRNA-148a apparently promotes β-cell de-differentiation to the immature mTORC1-high/AMPK-low phenotype with functional impairments in insulin secretion, increased mTORC1-driven endoplasmic reticulum stress, reduced autophagy and early β-cell apoptosis. In contrast to pasteurized cow's milk, milk's miRNAs are inactivated by bacterial fermentation, boiling and ultra-heat treatment and are missing in current infant formula. Persistent milk miRNA signaling adds a new perspective to the pathogenesis of T2DM and explains the protective role of breastfeeding but the diabetogenic effect of continued milk miRNA signaling by persistent consumption of pasteurized cow's milk.

Association between Dietary Calcium Intake and Adiposity in Male Adolescents

The aim was to investigate the possible association of dietary calcium intake with adiposity, insulin resistance, and adipocytokine values in adolescent boys. In this cross-sectional study, participants were 123 adolescent boys aged 13–15 years, who were divided into tertiles according to their dietary calcium intake. Dietary calcium intake was assessed using three 24 h dietary recalls. In addition, energy intake, body composition, physical activity (PA), and blood biochemical values were also measured. Mean body fat%, fat mass (FM), trunk FM, trunk fat%, and leptin differed between high and low tertiles of calcium intake after adjustment for age, pubertal stage, and PA. For the entire cohort, mean calcium intake was 786 ± 380 mg/day and was related to body mass index (BMI), FM, and trunk fat% but not to insulin resistance or adipocytokine values after adjusting for possible confounders. In addition, only 15.4% of the participants obtained or exceeded their mean dietary calcium intake requirements. These subjects who met their dietary calcium intake had significantly lower body fat% in comparison with subjects not meeting their dietary calcium intake. Odds ratio of being in the highest tertile of FM, trunk FM, and trunk fat% was 3.2–4.4 (95% confidence interval 1.19–12.47; p < 0.05) times higher for boys in low calcium intake tertile, compared to those boys in high calcium intake tertile. In conclusion, dietary calcium intake is inversely associated with total body and abdominal adiposity values in a specific group of healthy male adolescents with different body mass values.

A critical review of the role of milk and other dairy products in the development of obesity in children and adolescents

Existing reviews suggest that milk and other dairy products do not play a role in the development of obesity in childhood, but they do make an important contribution to children's nutrient intake. It is thus curious that public health advice on the consumption of dairy products for children is often perceived as unclear. The present review aimed to provide an overview of the totality of the evidence on the association between milk and other dairy products, and obesity and indicators of adiposity, in children. Our search identified forty-three cross-sectional studies, thirty-one longitudinal cohort studies and twenty randomised controlled trials. We found that milk and other dairy products are consistently found to be not associated, or inversely associated, with obesity and indicators of adiposity in children. Adjustment for energy intake tended to change inverse associations to neutral. Also, we found little evidence to suggest that the relationship varied by type of milk or dairy product, or age of the children, although there was a dearth of evidence for young children. Only nine of the ninety-four studies found a positive association between milk and other dairy products and body fatness. There may be some plausible mechanisms underlying the effect of milk and other dairy products on adiposity that influence energy and fat balance, possibly through fat absorption, appetite or metabolic activity of gut microbiota. In conclusion, there is little evidence to support a concern to limit the consumption of milk and other dairy products for children on the grounds that they may promote obesity.

Dairy Products: Is There an Impact on Promotion of Prostate Cancer? A Review of the Literature

This review of the literature aims to study potential associations between high consumption of milk and/or dairy products and prostate cancer (PC). Literature is scarce, yet there is a direct relationship between mTORC1 activation and PC; several ingredients in milk/dairy products, when in high concentrations, increase signaling of the mTORC1 pathway. However, there are no studies showing an unequivocal relationship between milk products PC initiation and/or progression. Three different reviews were conducted with articles published in the last 5 years: (M1) PC and intake of dairy products, taking into account the possible mTORC1signaling mechanism; (M2) Intake of milk products and incidence/promotion of PC; (M3) mTORC1 activation signaling pathway, levels of IGF-1 and PC; (M4) mTORC pathway and dairy products. Of the 32 reviews identified, only 21 met the inclusion criteria and were analyzed. There is little scientific evidence that directly link the three factors: incidence/promotion of PC, intake of dairy products and PC, and PC and increased mTORC1 signaling. Persistent hyper-activation of mTORC1 is associated with PC promotion. The activity of exosomal mRNA in cellular communication may lead to different impacts of different types of milk and whether or not mammalian milks will have their own characteristics within each species. Based on this review of the literature, it is possible to establish a relationship between the consumption of milk products and the progression of PC; we also found a possible association with PC initiation, hence it is likely that the intake of dairy products should be reduced or minimized in mens' diet.

Short sleep and low milk intake are associated with obesity in a community of school aged children from Argentina

OBJECTIVES

Understanding the factors related to obesity during childhood allows for improved preventive actions specifically adapted to particular communities. The purpose of this study was to identify individual and familiar factors related to obesity in children.

METHODS

A cross-sectional study was conducted in an urban community in Argentina during the years 2015-2016. Weight and height were measured on a probabilistic sample of 1366 schoolchildren aged 6 to 12 years. BMI categories were established according to International Obesity Task Force (IOTF) cut-offs. Data were analyzed using multivariate and logistic regression models. Independent variables corresponded to four domains: anthropometric, socioeconomic and demographic, nutritional, and energy balance.

RESULTS

Twenty percent of children were categorized as overweight (OW) and 12.2% were obese (OB). Parental IOTF grade was positively associated with childhood OW/OB (father B = 0.421 P = 0.000, OR = 1.52, 95% CI 1.24-1.88; mother B = 0.498 P = 0.000, OR = 1.65, 95% CI 1.37-1.97). The remaining variables were negatively associated with OW/OB: hours of sleep (B = -0.566 P = 0.001, OR = 0.57, 95% CI 0.41-0.79), physical activity (B = -0.362 P = 0.017, OR = 0.70, 95% CI 0-52-0.94), and daily milk intake (B = -0.178 P = 0.045, OR = 0.84, 95% CI 0.70-0.99). Parental IOTF predicted both OW and OB, while sleep hours predicted OW and physical activity predicted OB.

CONCLUSIONS

Family should be considered the initial target for effective strategies to reduce obesity. Like physical activity, the promotion of milk and dairy intake, as well as sleep, may have a major role in obesity reduction because of their protective effects in this community.

Vitamin D Levels and Cardiometabolic Markers in Indigenous Argentinean Children Living at Different Altitudes

The objective of this study was to assess the association between vitamin D and cardiometabolic markers in 2 indigenous communities from similar ethnic backgrounds, but living at different altitudes. A cross-sectional study compared 152 (72 females) indigenous schoolchildren from San Antonio de los Cobres (SAC), 3750 m above sea level, with 175 (86 females) from Chicoana (CH), 1400 m above sea level, mean age 9 years. Anthropometry, blood pressure, lipids, glucose, insulin, and vitamin D were assessed in spring season. The prevalence of children’s overweight/obesity was significantly lower in SAC, 9.2% (13), than in CH, 41.5% (71). There was a significantly higher prevalence of vitamin D deficiency (<20 ng/mL) in SAC (n = 103, 67.7%) than in CH (n = 62, 36.3%). SAC showed an inverse correlation between vitamin D and insulinemia (r = −0.17, P < .05), whereas CH showed an inverse correlation between vitamin D and systolic blood pressure (r = −0.19, P < .05), z-BMI (body mass index; r = −0.25, P < .01), triglycerides (r = −0.15, P < .05), glucose (r = −0.35, P < .05), and insulinemia (r = −0.24, P < .01). Multiple linear regression analysis showed that vitamin D (β = −.47; R² = .21) was significantly associated with SAC location, adjusted for confounding variables. Vitamin D levels were significantly and directly associated with altitude and inversely with metabolic markers, suggesting that populations living at high altitudes are at higher risk for future cardiovascular diseases.

Diseases of Civilization - Cancer, Diabetes, Obesity and Acne - the Implication of Milk, IGF-1 and mTORC1

Nutrition and food are one of the most complex aspects of human lives, being influenced by biochemical, psychological, social and cultural factors. The Western diet is the prototype of modern dietary pattern and is mainly characterized by the intake of large amounts of red meat, dairy products, refined grains and sugar. Large amounts of scientific evidence positively correlate Western diet to acne, obesity, diabetes, heart disease and cancer, the so-called "diseases of civilization". The pathophysiological common ground of all these pathologies is the IGF-1 and mTORC pathways, which will be disscussed further in this paper.

Consommation des produits lactés chez l’enfant et l’adolescent marocain de 2 à 16 ans: une étude monocentrique

Introduction

Evaluer la consommation quotidienne des produits laitiers dans une population d’enfants marocains et déterminer les facteurs associés pouvant influencer cette consommation.

Méthodes

Etude prospective du 1^er octobre 2013 au 31 avril 2014. Les enfants âgés entre 2 et 16 ans ont été inclus. Le recrutement a eu lieu dans la ville de Fès. Le recueil des données s’est fait à l’aide d’un questionnaire fréquentiel. Les parents et les enfants inclus ont été interrogés sur la consommation des produits laitiers et les facteurs socio-démographiques avec une évaluation anthropométrique des enfants. L’association des variables à la consommation des produits laitiers a été analysée en analyse univariée et multivariée par un modèle de régression logistique.

Résultats

L’enquête alimentaire avait intéressé 286 enfants dont 151 filles (52,8 %) et 131 garçons (45,8%). Les enfants âgés de 2 à 3 ans représentaient 26,4 %, ceux âgés de 4 à 7 ans 28,9 %, ceux âgés de 7 à 9 ans 18,3 % et les adolescents âgés de 10 à 16 ans 26,4 %. Les enfants consommaient en moyenne 2.5±1 produits laitiers par jour. Les enfants consommaient au moins 3 produits laitiers par jour dans 57,8% chez les enfants âgés de 2 à 3 ans, 53,6% chez les enfants âgés de 4 à 6 ans, 40% chez les enfants âgés de 7 à 9 ans et 41.2% chez les enfants âgés de 10 à 16 ans. Les facteurs associés à la consommation de trois produits laitiers minimum par jour en analyse univariée étaient le niveau d’instruction maternel analphabète p < 0.001 OR = 0.1 et primaire p = 0.002 OR = 0.1, le niveau socioéconomique familial moyen p < 0.001 OR = 3, l’âge p= 0.01 OR = 0.9 et l’indice de masse corporelle normal p = 0.01 OR = 2.5 et > 90° percentiles p < 0.001 OR = 6. Il existe un lien positif entre l’indice de masse corporelle > 90° percentiles p = 0.01 OR = 3.9 est et la quantité consommée des produits laitiers et négatif avec le faible niveau de scolarité maternel analphabète p = 0.008 OR = 0.1 et primaire p = 0.009 OR = 0.1.

Conclusion

La consommation du lait et des autres produits laitiers était inappropriée en particulier chez l’enfant âgé de 7 à 9 ans et l’adolescent de 10 à 16 ans. Le faible niveau d’éducation maternel et un indice de masse corporelle supérieur au 90° percentiles était des facteurs indépendamment associés à la consommation de moins de 3 produits laitiers par jour. La sensibilisation des parents et des enfants sur l’intérêt du lait et de ses dérivés dans l’alimentation de l’enfant est indispensable.

Dairy Fats and Cardiovascular Disease: Do We Really Need to be Concerned?

Cardiovascular diseases (CVD) remain a major cause of death and morbidity globally and diet plays a crucial role in the disease prevention and pathology. The negative perception of dairy fats stems from the effort to reduce dietary saturated fatty acid (SFA) intake due to their association with increased cholesterol levels upon consumption and the increased risk of CVD development. Institutions that set dietary guidelines have approached dairy products with negative bias and used poor scientific data in the past. As a result, the consumption of dairy products was considered detrimental to our cardiovascular health. In western societies, dietary trends indicate that generally there is a reduction of full-fat dairy product consumption and increased low-fat dairy consumption. However, recent research and meta-analyses have demonstrated the benefits of full-fat dairy consumption, based on higher bioavailability of high-value nutrients and anti-inflammatory properties. In this review, the relationship between dairy consumption, cardiometabolic risk factors and the incidence of cardiovascular diseases are discussed. Functional dairy foods and the health implications of dairy alternatives are also considered. In general, evidence suggests that milk has a neutral effect on cardiovascular outcomes but fermented dairy products, such as yoghurt, kefir and cheese may have a positive or neutral effect. Particular focus is placed on the effects of the lipid content on cardiovascular health.

Breakfast habits, dairy product consumption, physical activity, and their associations with body mass index in children aged 6-18

The purpose of this study was to determine breakfast habits, dairy product consumption, and physical activity and their relations with body mass index (BMI) in schoolchildren and adolescents. This cross-sectional, school-based study was performed with children aged 6-18 years. Height and weight were measured, and a BMI z-score was calculated for each child. Breakfast consumption frequency, intake of milk and other dairy products, physical activity habits, and mothers' employment status were assessed via a self-report questionnaire. Multiple linear regression analysis was used to estimate the association between these habits and BMI z-scores. Seven thousand one hundred sixteen children were included, 3445 (48.4%) female, with a mean age of 11.7 ± 2.7 years (5.8-18.9). Of these, 62.6% had breakfast every day. Boys ate breakfast daily significantly more often than girls (64.5 and 60.7%, respectively; p < 0.001). The percentage of children eating breakfast daily decreased with age (79.1% at 6-11 vs. 52.1% at 12-18 years, p < 0.001). Sixty-four (0.9%) children consumed no dairy products. Milk intake was negatively and significantly associated with BMI z-score (β = - 0.103, p < 0.001). Cheese consumption and the mother being employed were positively and significantly associated with BMI z-score (β = 0.517, p < 0.001, and β = 0.172, p < 0.001, respectively). Children engaging in physical activity had higher BMI z-score values than others (0.22 ± 0.01 vs. 0.12 ± 0.02, p < 0.001). Prevalence of overweight/obese was higher among children of working mothers compared to those of unemployed mothers (respectively, 29.3, 23.3%, p < 0.001).

CONCLUSIONS

Skipping breakfast was associated with overweight/obesity in schoolchildren and adolescents, while milk consumption exhibited a protective effect. What is known? • Dietary interventions should be incorporated into a multidisciplinary strategy for obesity prevention. • Most studies of habitual physical activity in children suggest that the overweight and obese children are less active. What is new? • Milk consumption seems to have a protective effect against overweight/obesity, irrespective of yogurt or cheese consumption. • Children engaging in greater physical activity had higher body mass index values than others.

Milk's Role as an Epigenetic Regulator in Health and Disease

It is the intention of this review to characterize milk's role as an epigenetic regulator in health and disease. Based on translational research, we identify milk as a major epigenetic modulator of gene expression of the milk recipient. Milk is presented as an epigenetic "doping system" of mammalian development. Milk exosome-derived micro-ribonucleic acids (miRNAs) that target DNA methyltransferases are implicated to play the key role in the upregulation of developmental genes such as FTO, INS, and IGF1. In contrast to miRNA-deficient infant formula, breastfeeding via physiological miRNA transfer provides the appropriate signals for adequate epigenetic programming of the newborn infant. Whereas breastfeeding is restricted to the lactation period, continued consumption of cow's milk results in persistent epigenetic upregulation of genes critically involved in the development of diseases of civilization such as diabesity, neurodegeneration, and cancer. We hypothesize that the same miRNAs that epigenetically increase lactation, upregulate gene expression of the milk recipient via milk-derived miRNAs. It is of critical concern that persistent consumption of pasteurized cow's milk contaminates the human food chain with bovine miRNAs, that are identical to their human analogs. Commercial interest to enhance dairy lactation performance may further increase the epigenetic miRNA burden for the milk consumer.

Relationship between dairy product intake during pregnancy and neonatal and maternal outcomes among Portuguese women

BACKGROUND

The role played by dairy product intake during pregnancy on neonatal outcomes has raised interest in the last few years. However, studies on this association remain scarce. Thus, the aim of this study was to determine the association between dairy product consumption during pregnancy and neonatal and maternal outcomes.

METHODS

A prospective study was conducted with 98 pregnant women, aged 18-40, from the city of Porto, Portugal. Socio-demographic and lifestyle characteristics were assessed through a questionnaire. Dairy product consumption was assessed with a three-day food diary completed during the first and second trimesters. Postpartum medical records were examined for neonatal and maternal outcomes. Multivariate linear regression analyses were performed to assess the association between dairy intake and neonatal and maternal outcomes, adjusting for dietary variables and maternal characteristics.

RESULTS

Compared to the first trimester pregnant women had higher energy intake and lower calcium, iodine and yogurt intake in the second trimester (P<0.05). Total dairy and yogurt intake in the first trimester were positively associated with head circumference and placental weight (respectively β=0.002, P=0.014, β=0.333, P=0.012). Change in total dairy intake between the second and first trimester was negatively associated with maternal weight gain during pregnancy (β=-0.007, P=0.020).

CONCLUSION

The findings of this study suggest that dairy product intake during pregnancy may have an effect on neonatal head circumference, placental weight, and gestational weight gain.

Associations between Consumption of Dairy Foods and Anthropometric Indicators of Health in Adolescents

Childhood obesity is associated with a greater chance of a lifetime of obesity. Evidence suggests dairy at recommended levels could be beneficial in maintaining normal weight and body composition. We assessed whether dairy consumption is associated with anthropometric indicators of health (z-scores for weight-for-age (WAZ); height-for-age (HAZ) and body mass index (BMIZ); waist-to-height ratio (WHtR); fat-free mass (FFM); and fat mass (FM)) in adolescents. In a cross-sectional study, 536 males and females ages 12–18 completed a 151-item semi-quantitative web-based food frequency questionnaire that included 34 dairy-containing foods. Dairy foods were categorized into milk, cheese, sweetened dairy, and total dairy. Anthropometrics were measured during school visits. Total dairy intake was associated with WAZ (β = 0.25 (95% CI: 0.01, 0.49), p = 0.045) and HAZ (β = 0.28 (95% CI: 0.04, 0.52), p = 0.021). In boys, total dairy was associated with WHtR (β = 0.02 (95% CI: 0.00, 0.04), p = 0.039), FFM (β = 4.83 (95% CI: 1.79, 7.87), p = 0.002), and FM (β = 3.89 (95% CI: 0.58, 7.21), p = 0.021), and cheese was associated with FFM (β = 4.22 (95% CI: 0.98, 7.47), p = 0.011). Dairy consumption seems to influence growth in both genders, and body composition and central obesity in boys. Prospective studies are needed to identify how types of dairy relate to growth, body composition, and central obesity of adolescents.

Association of lactase persistence genotype with milk consumption, obesity and blood pressure: a Mendelian randomization study in the 1982 Pelotas (Brazil) Birth Cohort, with a systematic review and meta-analysis

Background: Milk intake has been associated with lower blood pressure (BP) in observational studies, and randomized controlled trials suggested that milk-derived tripeptides have BP-lowering effects. Milk intake has also been associated with body mass index (BMI). Nevertheless, it is unclear whether increasing milk consumption would reduce BP in the general population.

Methods: We investigated the association of milk intake with obesity and BP using genetically-defined lactase persistence (LP) based on the rs4988235 polymorphism in a Mendelian randomization design in the 1982 Pelotas (Southern Brazil) Birth Cohort. These results were combined with published reports identified through a systematic review using meta-analysis.

Results: In the 1982 Pelotas Birth Cohort, milk intake was 42 [95% confidence interval (CI): 18; 67) ml/day higher in LP individuals. In conventional observational analysis, each 1-dl/day increase in milk intake was associated with −0.26 (95% CI: −0.33; −0.19) kg/m² in BMI and −0.31 (95% CI: −0.46; −0.16) and -0.35 (95% CI: −0.46; −0.23) mmHg in systolic and diastolic BP, respectively. These results were not corroborated when analysing LP status, but confidence intervals were large. In random effects meta-analysis, LP individuals presented higher BMI [0.17 (95% CI: 0.07; 0.27) kg/m²] and higher odds of overweight-obesity [1.09 (95% CI: 1.02; 1.17)]. There were no reliable associations for BP.

Conclusions: Our study supports that LP is positively associated with obesity, suggesting that the negative association of milk intake with obesity is likely due to limitations of conventional observational studies. Our findings also do not support that increased milk intake leads to lower BP.

Milk: an epigenetic amplifier of FTO-mediated transcription? Implications for Western diseases

Single-nucleotide polymorphisms within intron 1 of the FTO (fat mass and obesity-associated) gene are associated with enhanced FTO expression, increased body weight, obesity and type 2 diabetes mellitus (T2DM). The N⁶-methyladenosine (m⁶A) demethylase FTO plays a pivotal regulatory role for postnatal growth and energy expenditure. The purpose of this review is to provide translational evidence that links milk signaling with FTO-activated transcription of the milk recipient. FTO-dependent demethylation of m⁶A regulates mRNA splicing required for adipogenesis, increases the stability of mRNAs, and affects microRNA (miRNA) expression and miRNA biosynthesis. FTO senses branched-chain amino acids (BCAAs) and activates the nutrient sensitive kinase mechanistic target of rapamycin complex 1 (mTORC1), which plays a key role in translation. Milk provides abundant BCAAs and glutamine, critical components increasing FTO expression. CpG hypomethylation in the first intron of FTO has recently been associated with T2DM. CpG methylation is generally associated with gene silencing. In contrast, CpG demethylation generally increases transcription. DNA de novo methylation of CpG sites is facilitated by DNA methyltransferases (DNMT) 3A and 3B, whereas DNA maintenance methylation is controlled by DNMT1. MiRNA-29s target all DNMTs and thus reduce DNA CpG methylation. Cow´s milk provides substantial amounts of exosomal miRNA-29s that reach the systemic circulation and target mRNAs of the milk recipient. Via DNMT suppression, milk exosomal miRNA-29s may reduce the magnitude of FTO methylation, thereby epigenetically increasing FTO expression in the milk consumer. High lactation performance with increased milk yield has recently been associated with excessive miRNA-29 expression of dairy cow mammary epithelial cells (DCMECs). Notably, the galactopoietic hormone prolactin upregulates the transcription factor STAT3, which induces miRNA-29 expression. In a retrovirus-like manner milk exosomes may transfer DCMEC-derived miRNA-29s and bovine FTO mRNA to the milk consumer amplifying FTO expression. There is compelling evidence that obesity, T2DM, prostate and breast cancer, and neurodegenerative diseases are all associated with increased FTO expression. Maximization of lactation performance by veterinary medicine with enhanced miRNA-29s and FTO expression associated with increased exosomal miRNA-29 and FTO mRNA transfer to the milk consumer may represent key epigenetic mechanisms promoting FTO/mTORC1-mediated diseases of civilization.

Impact of diet on cardiometabolic health in children and adolescents

The manifestation of cardiovascular risk factors, such as hypertension, diabetes, and particularly obesity begins in children and adolescents, with deleterious effects for cardiometabolic health at adulthood. Although the impact of diet on cardiovascular risk factors has been studied extensively in adults, showing that their cardiometabolic health is strongly lifestyle-dependent, less is known about this impact in children and adolescents. In particular, little is known about the relationship between their dietary patterns, especially when derived a posteriori, and cardiovascular risk. An adverse association of cardiovascular health and increased intake of sodium, saturated fat, meat, fast food and soft drinks has been reported in this population. In contrast, vitamin D, fiber, mono-and poly-unsaturated fatty acids, dairy, fruits and vegetables were positively linked to cardiovascular health.

The aim of this review was to summarize current epidemiological and experimental evidence on the impact of nutrients, foods, and dietary pattern on cardiometabolic health in children and adolescents. A comprehensive review of the literature available in English and related to diet and cardiometabolic health in this population was undertaken via the electronic databases PubMed, Cochrane Library, and Medline.

Milk--A Nutrient System of Mammalian Evolution Promoting mTORC1-Dependent Translation

Based on own translational research of the biochemical and hormonal effects of cow's milk consumption in humans, this review presents milk as a signaling system of mammalian evolution that activates the nutrient-sensitive kinase mechanistic target of rapamycin complex 1 (mTORC1), the pivotal regulator of translation. Milk, a mammary gland-derived secretory product, is required for species-specific gene-nutrient interactions that promote appropriate growth and development of the newborn mammal. This signaling system is highly conserved and tightly controlled by the lactation genome. Milk is sufficient to activate mTORC1, the crucial regulator of protein, lipid, and nucleotide synthesis orchestrating anabolism, cell growth and proliferation. To fulfill its mTORC1-activating function, milk delivers four key metabolic messengers: (1) essential branched-chain amino acids (BCAAs); (2) glutamine; (3) palmitic acid; and (4) bioactive exosomal microRNAs, which in a synergistical fashion promote mTORC1-dependent translation. In all mammals except Neolithic humans, postnatal activation of mTORC1 by milk intake is restricted to the postnatal lactation period. It is of critical concern that persistent hyperactivation of mTORC1 is associated with aging and the development of age-related disorders such as obesity, type 2 diabetes mellitus, cancer, and neurodegenerative diseases. Persistent mTORC1 activation promotes endoplasmic reticulum (ER) stress and drives an aimless quasi-program, which promotes aging and age-related diseases.

Health effects of cow’s milk consumption in infants up to 3 years of age: a systematic review and meta-analysis

Objective

To summarize the best available evidence regarding the short- and long-term health effects of cow’s milk intake in healthy, full-term infants up to 3 years of age.

Design

We conducted a systematic review and meta-analysis.

Setting

We searched MEDLINE (via PubMed), EMBASE and the Cochrane Library between 1960 and July 2013 and manually reviewed reference lists of pertinent articles. Two researchers independently reviewed abstracts and full-text articles and extracted relevant data.

Subjects

We included (randomized/non-randomized) controlled trials and observational studies.

Results

We included data from twenty-three studies (one randomized controlled trial, four non-randomized controlled trials, eight case–control studies and ten cohort studies) for the evidence synthesis. Pooled results of four studies revealed a higher risk of Fe-deficiency anaemia for infants consuming cow’s milk compared with those consuming follow-on formula (relative risk=3·76; 95 % CI 2·73, 5·19). For type 1 diabetes mellitus, six out of seven case–control studies did not show a difference in the risk of developing this disease based on the age of introduction of cow’s milk. We did not find negative associations for other health effects.

Conclusions

Cow’s milk consumption in infancy is associated with an increased risk of developing Fe-deficiency anaemia. Limiting cow’s milk consumption may be important to ensure an adequate Fe intake for infants and toddlers. High-quality patient information for caregivers is needed on how infants’ Fe requirements can be met.

Associations between yogurt, dairy, calcium, and vitamin D intake and obesity among U.S. children aged 8-18 years: NHANES, 2005-2008

The aim of this study was to investigate associations of yogurt and dairy consumption with energy, macronutrient, calcium, and vitamin D intakes, and associations with indicators of overweight/obesity in U.S. children in the National Health and Nutrition Examination Survey (NHANES 2005–2008). Using 24-hour recall data, children 8–18 years of age were classified to dairy consumption groups of <1, 1 to <2, or 2+ dairy servings, and yogurt consumers were those who reported eating yogurt during at least one of two dietary intake interviews. NHANES anthropometric measurements were used, and BMI and BMI-for-age percentiles were calculated. Yogurt and dairy consumption were associated with higher intakes of calcium, vitamin D and protein. Yogurt intake was associated with lower total fat and saturated fat intakes and body fat as measured by subscapular skinfold thickness. This study supports consumption of yogurt and higher amounts of dairy as eating patterns associated with greater intake of specific shortfall nutrients, and lower body fat in U.S. children.

Milk consumption during pregnancy increases birth weight, a risk factor for the development of diseases of civilization

Antenatal dietary lifestyle intervention and nutrition during pregnancy and early postnatal life are important for appropriate lifelong metabolic programming. Epidemiological evidence underlines the crucial role of increased birth weight as a risk factor for the development of chronic diseases of civilization such as obesity, diabetes and cancer. Obstetricians and general practitioners usually recommend milk consumption during pregnancy as a nutrient enriched in valuable proteins and calcium for bone growth. However, milk is not just a simple nutrient, but has been recognized to function as an endocrine signaling system promoting anabolism and postnatal growth by activating the nutrient-sensitive kinase mTORC1. Moreover, pasteurized cow’s milk transfers biologically active exosomal microRNAs into the systemic circulation of the milk consumer apparently affecting more than 11 000 human genes including the mTORC1-signaling pathway. This review provides literature evidence and evidence derived from translational research that milk consumption during pregnancy increases gestational, placental, fetal and birth weight. Increased birth weight is a risk factor for the development of diseases of civilization thus involving key disciplines of medicine. With regard to the presented evidence we suggest that dietary recommendations promoting milk consumption during pregnancy have to be re-evaluated.

The pathogenic role of persistent milk signaling in mTORC1- and milk-microRNA-driven type 2 diabetes mellitus

Milk, the secretory product of the lactation genome, promotes growth of the newborn mammal. Milk delivers insulinotropic amino acids, thus maintains a molecular crosstalk with the pancreatic β-cell of the milk recipient. Homeostasis of β-cells and insulin production depend on the appropriate magnitude of mTORC1 signaling. mTORC1 is activated by branched-chain amino acids (BCAAs), glutamine, and palmitic acid, abundant nutrient signals of cow´s milk. Furthermore, milk delivers bioactive exosomal microRNAs. After milk consumption, bovine microRNA-29b, a member of the diabetogenic microRNA-29- family, reaches the systemic circulation and the cells of the milk consumer. MicroRNA-29b downregulates branchedchain α-ketoacid dehydrogenase, a potential explanation for increased BCAA serum levels, the metabolic signature of insulin resistance and type 2 diabetes mellitus (T2DM). In non-obese diabetic mice, microRNA-29b downregulates the antiapoptotic protein Mcl-1, which leads to early β-cell death. In all mammals except Neolithic humans, milk-driven mTORC1 signaling is physiologically restricted to the postnatal period. In contrast, chronic hyperactivated mTORC1 signaling has been associated with the development of age-related diseases of civilization including T2DM. Notably, chronic hyperactivation of mTORC1 enhances endoplasmic reticulum stress that promotes apoptosis. In fact, hyperactivated β-cell mTORC1 signaling induced early β-cell apoptosis in a mouse model. The EPIC-InterAct Study demonstrated an association between milk consumption and T2DM in France, Italy, United Kingdom, Germany, and Sweden. In contrast, fermented milk products and cheese exhibit an inverse correlation. Since the early 1950´s, refrigeration technology allowed widespread consumption of fresh pasteurized milk, which facilitates daily intake of bioactive bovine microRNAs. Persistent uptake of cow´s milk-derived microRNAs apparently transfers an overlooked epigenetic diabetogenic program that should not reach the human food chain.

Translating human biology (introduction to special issue)

OBJECTIVES

Introducing a special issue on "Translating Human Biology," we pose two basic questions: Is human biology addressing the most critical challenges facing our species? How can the processes of translating our science be improved and innovated?

METHODS

We analyze articles published in American Journal of Human Biology from 2004-2013, and find there is very little human biological consideration of issues related to most of the core human challenges such as water, energy, environmental degradation, or conflict. There is some focus on disease, and considerable focus on food/nutrition. We then introduce this special volume with reference to the following articles that provide exemplars for the process of how translation and concern for broader context and impacts can be integrated into research.

CONCLUSIONS

Human biology has significant unmet potential to engage more fully in translation for the public good, through consideration of the topics we focus on, the processes of doing our science, and the way we present our domain expertise.

Dairy intakes at age 10 years do not adversely affect risk of excess adiposity at 13 years

Evidence of an association between milk intake and childhood adiposity remains inconsistent, with few data available regarding the effects of the amount of dairy fat consumed. This study examined the relation between dairy consumption (total, full, and reduced fat) at age 10 y on risk of excess adiposity at age 13 y in participants of the Avon Longitudinal Study of Parents and Children (ALSPAC; n = 2455). Intakes were assessed by 3-d dietary records. Total body fat mass (TBFM) using dual-energy X-ray absorptiometry was examined at 13 y. Outcomes included excess TBFM (top quintile of TBFM), overweight, and change in body mass index (BMI). The highest vs. lowest quartile of total dairy consumers (g/d) at age 10 y did not have an increased risk of excess TBFM (OR: 0.73; 95% CI: 0.46, 1.16; P-trend = 0.28) or overweight (OR: 0.69; 95% CI: 0.41, 1.15; P = 0.24) at age 13 y. Children in the highest quartile of full-fat dairy intakes vs. those in the lowest quartile had a reduced risk of excess TBFM (OR: 0.64; 95% CI: 0.41, 1.00; P = 0.04) and a suggestion of a reduction in overweight (OR: 0.65; 95% CI: 0.40, 1.06; P = 0.19) at age 13 y. Furthermore, the highest vs. lowest consumers of full-fat products had smaller gains in BMI during follow-up [2.5 kg/m² (95% CI: 2.2, 2.7) vs. 2.8 kg/m² (95% CI: 2.5, 3.0); P < 0.01]. Associations with reduced-fat dairy consumption did not attain statistical significance. In this study, dairy consumption was not related to excess fat accumulation during late childhood. Estimates had wide confidence limits but generally showed inverse relations between dairy intakes and risk of excess adiposity. Additional prospective research is warranted to confirm the effects of dairy intake on obesity in children.

Dairy consumption and pre-school, school-age and adolescent obesity in developed countries: a systematic review and meta-analysis

Childhood obesity, the primary health problem affecting children in developed countries, has been attributed in part to changes in dietary patterns. Secular trends suggest a decrease in childhood dairy consumption coinciding with the rise in obesity prevalence. The objective of the present systematic review and meta-analysis was to consider evidence of associations between dairy intake and adiposity in pre-schoolers, school-age children and adolescents in developed countries. Of 36 studies included in the systematic review, sufficient data for effect size estimation and inclusion in the meta-analysis were obtained from 22 studies. No significant association was found between dairy intake and adiposity in the aggregated data, although statistical heterogeneity was high (I(2) = 0.72). Among adolescents, however, dairy intake was inversely associated with adiposity (effect size -0.26, [-0.38, -0.14], P < 0.0001). Effect size was not predicted by exposure variable (milk vs. dairy), study design, statistical methods, outcome variables or sex. Interpretation of results was complicated by variability in study methods and insufficient adjustment for relevant confounders, particularly dietary reporting accuracy, sweetened beverage intake and pubertal development. Despite limitations, available data suggest a neutral effect of dairy intake on adiposity during early and middle childhood and a modestly protective effect in adolescence.

Long-term commercial cow's milk consumption and its effects on metabolic parameters associated with obesity in young mice

SCOPE

Research has demonstrated that consumption of milk promotes weight loss and satiety, however conflicting evidence also exists. Therefore, we tested the effect of long-term milk consumption on body weight and metabolic parameters.

METHODS AND RESULTS

Newly weaned mice received whole milk, low-fat milk, or water as control for 17 weeks and serum, liver, and white adipose tissue (WAT) were tested for parameters associated with obesity and diabetes. Our results show that low-fat milk leads to the same overall caloric intake and body weight as the control group. However, the whole-milk group consumed more calories and reached a higher body weight. In addition, in the low-fat milk group, cholesterol, HDL-cholesterol, triglycerides, leptin, ghrelin, insulin, corticosterone, and glucagon were not significantly different than the control group. In contrast, in the whole-milk group, cholesterol, HDL-cholesterol, triglycerides, and glucagon were high compared with the control group. Metabolism in both liver and WAT showed only slight differences between the milk groups. Whereas the whole-milk group showed reduced insulin signaling in WAT, the low-fat milk group exhibited increased insulin signaling.

CONCLUSION

Whole-milk consumption leads to increased body weight and caloric intake and reduced insulin signaling in WAT, as opposed to low-fat milk consumption.