Background: The purpose of this study was to examine whether extended use of a variety of screen-based devices, in addition to television, was associated with poor dietary habits and other health-related characteristics and behaviors among US adults. The recent phenomenon of binge-watching was also explored.Methods: A survey to assess screen time across multiple devices, dietary habits, sleep duration and quality, perceived stress, self-rated health, physical activity, and body mass index, was administered to a sample of US adults using the Qualtrics platform and distributed via Amazon Mechanical Turk (MTurk). Participants were adults 18 years of age and older, English speakers, current US residents, and owners of a television and at least one other device with a screen. Three different screen time categories (heavy, moderate, and light) were created for total screen time, and separately for screen time by type of screen, based on distribution tertiles. Kruskal-Wallis tests were conducted to examine differences in dietary habits and health-related characteristics between screen time categories.Results: Aggregate screen time across all devices totaled 17.5 h per day for heavy users. Heavy users reported the least healthful dietary patterns and the poorest health-related characteristics – including self-rated health – compared to moderate and light users. Moreover, unique dietary habits emerged when examining dietary patterns by type of screen separately, such that heavy users of TV and smartphone displayed the least healthful dietary patterns compared to heavy users of TV-connected devices, laptop, and tablet. Binge-watching was also significantly associated with less healthy dietary patterns, including frequency of fast-food consumption as well as eating family meals in front of a television, and perceived stress.Conclusions: The present study found that poorer dietary choices, as well as other negative health-related impacts, occurred more often as the viewing time of a variety of different screen-based devices increased in a sample of US adults. Future research is needed to better understand what factors among different screen-based devices might affect health behaviors and in turn health-related outcomes. Research is also required to better understand how binge-watching behavior contributes impacts health-related behaviors and characteristics.

Life cycle assessment (LCA) evaluates environmental impacts of a product from material extraction through disposal. Applications of LCA in evaluating diets and foods indicate that plant-based foods have lower environmental impacts than animal-based foods, whether on the basis of total weight or weight of the protein content. However, LCA comparisons do not differentiate the true biological value of protein bioavailability. This paper presents a methodology to incorporate protein quality and quantity using the digestible indispensable amino acid score (DIAAS) when making comparisons using LCA data. The methodology also incorporates the Food and Drug Administration’s (FDA) reference amounts customarily consumed (RACCs) to best represent actual consumption patterns. Integration of these measures into LCA provides a mechanism to identify foods that offer balance between the true value of their protein and environmental impacts. To demonstrate, this approach is applied to LCA data regarding common protein foods’ global warming potential (GWP). The end result is a ratio-based score representing the biological value of protein on a GWP basis. Principal findings show that protein powders provide the best efficiency while cheeses, grains, and beef are the least efficient. This study demonstrates a new way to evaluate foods in terms of nutrition and sustainability.

Food waste contributes to adverse environmental and economic outcomes, and substantial food waste occurs at the household level in the US. This study explored perceived household food waste changes during the COVID-19 pandemic and related factors. A total of 946 survey responses from primary household food purchasers were analyzed. Demographic, COVID-19-related household change, and household food waste data were collected in October 2020. Wilcoxon signed-rank was used to assess differences in perceived food waste. A hierarchical binomial logistic regression analysis was conducted to examine whether COVID-19-related lifestyle disruptions and food-related behavior changes increased the likelihood of household food waste. A binomial logistic regression was conducted to explore the contribution of different food groups to the likelihood of increased food waste. Perceived food waste, assessed as the estimated percent of food wasted, decreased significantly during the pandemic (z = −7.47, p < 0.001). Food stockpiling was identified as a predictor of increased overall food waste during the pandemic, and wasting fresh vegetables and frozen foods increased the odds of increased food waste. The results indicate the need to provide education and resources related to food stockpiling and the management of specific food groups during periods of disruption to reduce food waste.

Although vegetarian diets are considered generally protective against chronic disease, nutrient deficiencies, including protein, are possible due to low bioavailability from plant-based sources. The consequences of inadequate dietary protein include reduced lean body mass (LBM) and muscle weakness. This study examined relationships between protein intake, strength, and LBM in 37 underactive vegetarians and recorded the impact of protein supplementation (18 g/day mung bean protein) on these indices utilizing an eight-week, randomized, controlled, feeding trial. Both handgrip and knee flexor and extensor strength were measured at baseline and week eight. At baseline, LBM was significantly related to grams of protein consumed daily. LBM was also correlated to grip strength (r = 0.569, p < 0.001) and lower body strength (r = 0.763 to 0.784; p < 0.001). Twenty-five vegetarians completed the feeding trial, including 11 in the protein supplementation group (PRO) and 14 in the control group (CON). At the end of the trial, LBM and strength did not differ significantly between groups. However, the average percent change for grip, flexor, and extensor strength did differ between PRO and CON participants (+2.9 ± 7.2% and −2.6 ± 7.3% respectively, p = 0.05). Thus, there were strong associations between dietary protein, LBM, and strength in vegetarians and an indication that supplementary vegetarian protein increased strength in the absence of exercise and independent of LBM.

Objective: To explore adherence to a plant-based diet from the perspective of goals- and motivations-based systems.Design: A cross-sectional, survey-based study was conducted regarding eating patterns, goals and motivations for current eating habits.Setting: Data were collected using an online survey platform, including the Goal Systems Assessment Battery (GSAB) and other survey tools.Participants: University students were recruited, including thirty-three students reporting successful maintenance of a plant-based diet (Adherents) and sixty-three students trying to adhere to a plant-based diet (Non-adherents).Results: Using GSAB subscale scores, discriminant function analyses significantly differentiated adherents v. non-adherents, accounting for 49·0 % of between-group variance (χ² (13) = 42·03, P < 0·000). It correctly classified 72·7 % of adherents and 88·9 % of non-adherents. Constructs including value, self-efficacy, planning/stimulus control and positive affect were significant and included in the discriminant function. Logistic regression results suggested that participants who successfully adhered to a plant-based diet were seventeen times more likely to report ‘To manage or treat a medical condition’ as motivation and almost seven times more likely to report ‘To align with my ethical beliefs’ as motivation compared with non-adherents. However, these participants were 94 % less likely to report ‘To maintain and/or improve my health’ as motivation compared with non-adherents. Controlling for motivations, hierarchical logistic regression showed that only planning as part of the GSAB self-regulatory system predicted adherence to a plant-based diet.Conclusions: Values-based approaches to plant-based diets, including consideration for ethical beliefs, self-efficacy and proper planning, may be key for successful maintenance of this diet long-term.