Three Weeks Daily Intake of Matcha Green Tea Powder Affects Substrate Oxidation during Moderate-Intensity Exercise in Females

Artificial green tea extracts may enhance exercise-induced fat oxidation. Natural Matcha green tea consumption involves the ingestion of the powdered green tea leaves. We examined the effects of three weeks daily intake of Matcha green tea powder on substrate oxidation during moderate-intensity exercise in females. Females with a regular menstrual cycle (n  = 12, age: 28 ± 10 yr, body mass: 69 ± 17 kg, height: 163 ± 6 cm) volunteered to complete an incremental walking test to determine the individual moderate exercise intensity (four metabolic equivalent) for the subsequent 30-min treadmill walk. The study had a randomized placebo-controlled cross-over design with participants tested between day 9 and 11 of the menstrual cycle (follicular phase). Participants consumed 3x1 gram capsules of Matcha premium grade, (OMGTea Ltd, UK) per day for three weeks, with the final dose (1 gram) two hours before the 30-min walk (walking speed: 5.8 ± 0.4 km·h−1). Matcha had no effect on physiological responses (e.g. heart rate, placebo: 127 ± 14; Matcha: 124 ± 14 beats·min−1, p  = 0.154), but resulted in lower respiratory exchange ratio (placebo: 0.872 ± 0.040; Matcha: 0.839 ± 0.035) (p  = 0.033), higher fat oxidation by 35 ± 47% (placebo: 0.21 ± 0.08; Matcha: 0.26 ± 0.06 g·min−1) (p  = 0.034), and lower carbohydrate oxidation (placebo: 0.75 ± 0.21; Matcha: 0.60 ± 0.18 g·min−1) (p = 0.048) during the 30-min moderate-intensity walk. Energy expenditure was similar for both conditions. There was no significant correlation between body fat % and the absolute or relative change in Matcha-induced fat oxidation during exercise. Continuous intake of Matcha green tea effects exercise-induced metabolic responses by enhancing fat oxidation during moderate-intensity exercise in adult females, seemingly independent of body composition

Infant feeding experiences and concerns among caregivers early in the COVID‐19 State of Emergency in Nova Scotia, Canada

Abstract The global emergency caused by the novel coronavirus (COVID‐19) pandemic has impacted access to goods and services such as health care and social supports, but the impact on infant feeding remains unclear. Thus, the objective of this study was to explore how caregivers of infants under 6 months of age perceived changes to infant feeding and other food and health‐related matters during the COVID‐19 State of Emergency in Nova Scotia, Canada. Four weeks after the State of Emergency began, between 17 April and 15 May 2020, caregivers completed this online survey, including the Perceived Stress Scale. Participants (n = 335) were 99% female and mostly White (87%). Over half (60%) were breastfeeding, and 71% had a household income over CAD$60,000. Most participants (77%) received governmental parental benefits before the emergency, and 59% experienced no COVID‐19‐related economic changes. Over three quarters of participants (77%) scored moderate levels of perceived stress. Common themes of concern included social isolation, COVID‐19 infection (both caregiver and infant), and a lack of access to goods, namely, human milk substitutes (‘infant formula’), and services, including health care, lactation support, and social supports. Most COVID‐19‐related information was sought from the internet and social media, so for broad reach, future evidence‐based information should be shared via online platforms. Although participants were experiencing moderate self‐perceived stress and shared numerous concerns, very few COVID‐19‐related changes to infant feeding were reported, and there were few differences by socio‐economic status, likely due to a strong economic safety net in this Canadian setting

Risk of COVID-19 after natural infection or vaccinationResearch in context

Background: While vaccines have established utility against COVID-19, phase 3 efficacy studies have generally not comprehensively evaluated protection provided by previous infection or hybrid immunity (previous infection plus vaccination). Individual patient data from US government-supported harmonized vaccine trials provide an unprecedented sample population to address this issue. We characterized the protective efficacy of previous SARS-CoV-2 infection and hybrid immunity against COVID-19 early in the pandemic over three-to six-month follow-up and compared with vaccine-associated protection. Methods: In this post-hoc cross-protocol analysis of the Moderna, AstraZeneca, Janssen, and Novavax COVID-19 vaccine clinical trials, we allocated participants into four groups based on previous-infection status at enrolment and treatment: no previous infection/placebo; previous infection/placebo; no previous infection/vaccine; and previous infection/vaccine. The main outcome was RT-PCR-confirmed COVID-19 >7–15 days (per original protocols) after final study injection. We calculated crude and adjusted efficacy measures. Findings: Previous infection/placebo participants had a 92% decreased risk of future COVID-19 compared to no previous infection/placebo participants (overall hazard ratio [HR] ratio: 0.08; 95% CI: 0.05–0.13). Among single-dose Janssen participants, hybrid immunity conferred greater protection than vaccine alone (HR: 0.03; 95% CI: 0.01–0.10). Too few infections were observed to draw statistical inferences comparing hybrid immunity to vaccine alone for other trials. Vaccination, previous infection, and hybrid immunity all provided near-complete protection against severe disease. Interpretation: Previous infection, any hybrid immunity, and two-dose vaccination all provided substantial protection against symptomatic and severe COVID-19 through the early Delta period. Thus, as a surrogate for natural infection, vaccination remains the safest approach to protection. Funding: National Institutes of Health

Risk of COVID-19 after natural infection or vaccinationResearch in context

Summary: Background: While vaccines have established utility against COVID-19, phase 3 efficacy studies have generally not comprehensively evaluated protection provided by previous infection or hybrid immunity (previous infection plus vaccination). Individual patient data from US government-supported harmonized vaccine trials provide an unprecedented sample population to address this issue. We characterized the protective efficacy of previous SARS-CoV-2 infection and hybrid immunity against COVID-19 early in the pandemic over three-to six-month follow-up and compared with vaccine-associated protection. Methods: In this post-hoc cross-protocol analysis of the Moderna, AstraZeneca, Janssen, and Novavax COVID-19 vaccine clinical trials, we allocated participants into four groups based on previous-infection status at enrolment and treatment: no previous infection/placebo; previous infection/placebo; no previous infection/vaccine; and previous infection/vaccine. The main outcome was RT-PCR-confirmed COVID-19 >7–15 days (per original protocols) after final study injection. We calculated crude and adjusted efficacy measures. Findings: Previous infection/placebo participants had a 92% decreased risk of future COVID-19 compared to no previous infection/placebo participants (overall hazard ratio [HR] ratio: 0.08; 95% CI: 0.05–0.13). Among single-dose Janssen participants, hybrid immunity conferred greater protection than vaccine alone (HR: 0.03; 95% CI: 0.01–0.10). Too few infections were observed to draw statistical inferences comparing hybrid immunity to vaccine alone for other trials. Vaccination, previous infection, and hybrid immunity all provided near-complete protection against severe disease. Interpretation: Previous infection, any hybrid immunity, and two-dose vaccination all provided substantial protection against symptomatic and severe COVID-19 through the early Delta period. Thus, as a surrogate for natural infection, vaccination remains the safest approach to protection. Funding: National Institutes of Health