There is an ongoing debate about the possible influences of nonnutritive sweeteners (NNS) on body weight. We conducted a systematic review and meta-analysis of randomized controlled trials (RCTs) with NNS to assess their impact on body weight. We systematically searched for RCTs at least 4 weeks in duration, evaluating the effect of NNS on body weight, both in subjects with healthy weight and in subjects with overweight/obesity at any age, and compared the effects of NNS vs caloric and noncaloric comparators. The primary outcome was the difference in body weight between NNS and comparators. Twenty studies were eligible (n = 2914). Participants consuming NNS showed significant weight/BMI differences favouring NNS compared with nonusers. Grouping by nature of comparator revealed that NNS vs placebo/no intervention and NNS vs water produced no effect. When comparing NNS vs sucrose, significant weight/BMI differences appeared favouring NNS. Consumption of NNS led to significantly negative weight/BMI differences in unrestricted energy diets, but not in weight-reduction diets. Participants with overweight/obesity and adults showed significant favourable weight/BMI differences with NNS. Data suggest that replacing sugar with NNS leads to weight reduction, particularly in participants with overweight/obesity under an unrestricted diet, information that could be utilized for evidence-based public policy decisions. K E Y W O R D S artificial sweeteners, body weight, obesity, systematic review

Evidence consistently suggests that plant-based diets promote human and planetary health. Reducing large-scale animal-based food production generates environmental benefits, as the entire livestock agriculture chain plays an outsized role in greenhouse gas emissions, land change and degradation, and scarcity-weighted water use. However, substituting animal products with their plant-based counterparts must come with consideration of the nutritional quality and resource usage of plant-based food production and processing operations. Several policy reforms have been implemented at the national, state, and municipal levels in the United States to support a transition toward more plant-based diets. Federal programs such as the Supplemental Nutrition Assistance Program and the Dietary Guidelines for Americans generally promote the consumption of unprocessed plant-based foods but include little to no information on sustainability and the harmful environmental impact of animal-based foods. National policies are complemented by state efforts aimed at incentivizing produce purchased from local suppliers and encouraging resource-conserving agriculture. At the local level, public schools are implementing programs to promote plant-based protein on their menus, and urban gardens are sprouting across the country to increase access to organic farming. This mini-review examines these policy reforms and behavioral intervention strategies, based on the social-ecological model, and discuss their capacity and limitations to promote a shift toward sustainably produced plant-based diets in the United States. We conclude that transforming the food systems toward plant-based diets in the animal-centered United States requires multi-sector collaboration and context-specific policy solutions to address diet-related climate concerns without neglecting health, social, and financial constraints.

Background Krukenberg tumor is a rare metastatic tumor of the ovary with histopathological features known as signet ring cells. It usually develops in women around 45 years of age. However, here we describe an uncommon case in a 38-year-old pregnant woman. We report this case due to our unusual findings, the uncommon presentation in this younger age bracket, its diagnostic challenge, and poor prognosis. Case presentation We describe a unique case of a young Mexican woman with a history of painful vaginal bleeding at 13 weeks of pregnancy and treated for abruptio placentae. In her routine prenatal visit at week 20 of pregnancy, she was found to have a uterine fundus exceeding the expected measure for her gestational age and was referred to the hospital to discard polyhydramnios. Upon admission, a pelvic ultrasound was performed displaying normal findings in a 25-week pregnancy, and also showing bilateral enlarged ovaries with heterogeneous echogenicity. Magnetic resonance imaging revealed a left tumoral lesion with dimensions of 22.1 × 13.6 × 16.3 cm presenting regular lobulated contours with displacement of peripheral structures and mild compression of the bladder, the left ureter, and the inferior vena cava. The lesion was heterogeneous with irregular borders. The patient was scheduled for a cesarean section; during the operation, the abdominal cavity showed bilateral tumors compatible with MRI findings. The ovarian tumors were sent to pathology, and the results showed poorly differentiated mucinous adenocarcinoma (World Health Organization grade III) with extensive signet ring cells, indicative of a Krukenberg tumor. Conclusion This case report describes an uncommon example of a young pregnant woman without identifiable risk factors for gastric cancer who manifested a Krukenberg tumor. This incidental finding suggests that pregnancy obscured the cancer’s clinical appearance. The rapid deterioration in the patient’s condition corresponds to what is described in the literature. The limited information regarding this neoplasm in Mexico and the torpid evolution of the case highlight the importance of conducting additional studies to generate therapeutic interventions aimed at increasing overall survival.

The vegan diet excludes animal-derived product consumption and has been linked with cardiovascular benefits. The objective of the present comparative pilot study was to analyze dietary lipid intake, evaluate the conventional clinical lipid profile, extract fatty acids from triglycerides' molecules among Mexican individuals with prolonged exposure to a vegan diet (≥ 3 years), and compare these outcomes with omnivore controls. A case-control and cross-sectional comparative pilot study was performed between 2016 and 2017. Vegans were paired in a 1:1 ratio with omnivores from Merida, Mexico. A 144-item Semi-Quantitative Food Frequency Questionnaire was conducted to evaluate eating patterns. Serum fatty acids were determined from total blood with a gas chromatography assay. Lower total cholesterol, stearic, arachidonic, and trans fatty acids intake (p<0.001, 0.014, <0.001, 0.009 respectively), but higher consumption of lauric acid were observed in the vegan group (p= 0.007). Vegan-diet consumers also presented greater triglycerides concentrations (p= 0.049); however, when analyzing fatty acids, we identified lower levels of stearic, oleic, linoleic, and arachidonic acids (p= 0.002, 0.030, 0.015, 0.008, respectively). Following a vegan diet for more than three years generate modifications in serum concentrations of saturated and polyunsaturated ω-6 fatty acids, which could lower inflammatory markers' biosynthesis. Potential benefits regarding cardiovascular risk may be assumed in favor of vegan individuals.