The infant gut is rapidly colonized by microorganisms soon after birth, and the composition of the microbiota is dynamic in the first year of life. Although a stable microbiome may not be established until 1 to 3 years after birth, the infant gut microbiota appears to be an important predictor of health outcomes in later life. We obtained stool at one year of age from 173 white Caucasian and 182 South Asian infants from two Canadian birth cohorts to gain insight into how maternal and early infancy exposures influence the development of the gut microbiota. We investigated whether the infant gut microbiota differed by ethnicity (referring to groups of people who have certain racial, cultural, religious, or other traits in common) and by breastfeeding status, while accounting for variations in maternal and infant exposures (such as maternal antibiotic use, gestational diabetes, vegetarianism, infant milk diet, time of introduction of solid food, infant birth weight, and weight gain in the first year). We demonstrate that ethnicity and infant feeding practices independently influence the infant gut microbiome at 1 year, and that ethnic differences can be mapped to alpha diversity as well as a higher abundance of lactic acid bacteria in South Asians and a higher abundance of genera within the order Clostridiales in white Caucasians. The infant gut microbiome is influenced by ethnicity and breastfeeding in the first year of life. Ethnic differences in the gut microbiome may reflect maternal/infant dietary differences and whether these differences are associated with future cardiometabolic outcomes can only be determined after prospective follow-up.
Protein and other compounds can exert anabolic effects on skeletal muscle, particularly in conjunction with exercise. The objective of this study was to evaluate the efficacy of twice daily consumption of a protein-based, multi-ingredient nutritional supplement to increase strength and lean mass independent of, and in combination with, exercise in healthy older men. Forty-nine healthy older men (age: 73 ± 1 years [mean ± SEM]; BMI: 28.5 ± 1.5 kg/m2) were randomly allocated to 20 weeks of twice daily consumption of either a nutritional supplement (SUPP; n = 25; 30 g whey protein, 2.5 g creatine, 500 IU vitamin D, 400 mg calcium, and 1500 mg n-3 PUFA with 700 mg as eicosapentanoic acid and 445 mg as docosahexanoic acid); or a control (n = 24; CON; 22 g of maltodextrin). The study had two phases. Phase 1 was 6 weeks of SUPP or CON alone. Phase 2 was a 12 week continuation of the SUPP/CON but in combination with exercise: SUPP + EX or CON + EX. Isotonic strength (one repetition maximum [1RM]) and lean body mass (LBM) were the primary outcomes. In Phase 1 only the SUPP group gained strength (Σ1RM, SUPP: +14 ± 4 kg, CON: +3 ± 2 kg, P < 0.001) and lean mass (LBM, +1.2 ± 0.3 kg, CON: -0.1 ± 0.2 kg, P < 0.001). Although both groups gained strength during Phase 2, upon completion of the study upper body strength was greater in the SUPP group compared to the CON group (Σ upper body 1RM: 119 ± 4 vs. 109 ± 5 kg, P = 0.039). We conclude that twice daily consumption of a multi-ingredient nutritional supplement increased muscle strength and lean mass in older men. Increases in strength were enhanced further with exercise training. Trial Registration: ClinicalTrials.gov NCT02281331
Purpose: There is an ever-growing body of literature examining the relationship between dietary omega-3 polyunsaturated fatty acids (ω3 PUFAs) and cerebral structure and function throughout life. In light of this, the use of ω3 PUFAs, namely, long-chain (LC) ω3 PUFAs (i.e., eicosapentaenoic acid and docosahexaenoic acid), as a therapeutic strategy to mitigate cognitive impairment, and progression to Alzheimer’s disease is an attractive prospect. This review aims to summarise evidence reported by observational studies and clinical trials that investigated the role of LC ω3 PUFAs against cognition impairment and future risk of Alzheimer’s disease. Methods: Studies were identified in PubMed and Scopus using the search terms “omega-3 fatty acids”, “Alzheimer’s disease” and “cognition”, along with common variants. Inclusion criteria included observational or randomised controlled trials (RCTs) with all participants aged ≥ 50 years that reported on the association between LC ω3 PUFAs and cognitive function or biological markers indicative of cognitive function linked to Alzheimer’s disease. Results: Evidence from 33 studies suggests that dietary and supplemental LC ω3 PUFAs have a protective effect against cognitive impairment. Synaptic plasticity, neuronal membrane fluidity, neuroinflammation, and changes in expression of genes linked to cognitive decline have been identified as potential targets of LC ω3 PUFAs. The protective effects LC ω3 PUFAs on cognitive function and reduced risk of Alzheimer’s disease were supported by both observational studies and RCTs, with RCTs suggesting a more pronounced effect in individuals with early and mild cognitive impairment. Conclusion: The findings of this review suggest that individuals consuming higher amounts of LC ω3 PUFAs are less likely to develop cognitive impairment and that, as a preventative strategy against Alzheimer’s disease, it is most effective when dietary LC ω3 PUFAs are consumed prior to or in the early stages of cognitive decline.