Cardiometabolic Effects of Omnivorous vs Vegan Diets in Identical Twins

Abstract

ImportanceIncreasing evidence suggests that, compared with an omnivorous diet, a vegan diet confers potential cardiovascular benefits from improved diet quality (ie, higher consumption of vegetables, legumes, fruits, whole grains, nuts, and seeds).ObjectiveTo compare the effects of a healthy vegan vs healthy omnivorous diet on cardiometabolic measures during an 8-week intervention.Design, Setting, and ParticipantsThis single-center, population-based randomized clinical trial of 22 pairs of twins (N = 44) randomized participants to a vegan or omnivorous diet (1 twin per diet). Participant enrollment began March 28, 2022, and continued through May 5, 2022. The date of final follow-up data collection was July 20, 2022. This 8-week, open-label, parallel, dietary randomized clinical trial compared the health impact of a vegan diet vs an omnivorous diet in identical twins. Primary analysis included all available data.InterventionTwin pairs were randomized to follow a healthy vegan diet or a healthy omnivorous diet for 8 weeks. Diet-specific meals were provided via a meal delivery service from baseline through week 4, and from weeks 5 to 8 participants prepared their own diet-appropriate meals and snacks.Main Outcomes and MeasuresThe primary outcome was difference in low-density lipoprotein cholesterol concentration from baseline to end point (week 8). Secondary outcome measures were changes in cardiometabolic factors (plasma lipids, glucose, and insulin levels and serum trimethylamine N-oxide level), plasma vitamin B12 level, and body weight. Exploratory measures were adherence to study diets, ease or difficulty in following the diets, participant energy levels, and sense of well-being.ResultsA total of 22 pairs (N = 44) of twins (34 [77.3%] female; mean [SD] age, 39.6 [12.7] years; mean [SD] body mass index, 25.9 [4.7]) were enrolled in the study. After 8 weeks, compared with twins randomized to an omnivorous diet, the twins randomized to the vegan diet experienced significant mean (SD) decreases in low-density lipoprotein cholesterol concentration (−13.9 [5.8] mg/dL; 95% CI, −25.3 to −2.4 mg/dL), fasting insulin level (−2.9 [1.3] μIU/mL; 95% CI, −5.3 to −0.4 μIU/mL), and body weight (−1.9 [0.7] kg; 95% CI, −3.3 to −0.6 kg).Conclusions and RelevanceIn this randomized clinical trial of the cardiometabolic effects of omnivorous vs vegan diets in identical twins, the healthy vegan diet led to improved cardiometabolic outcomes compared with a healthy omnivorous diet. Clinicians can consider this dietary approach as a healthy alternative for their patients.Trial RegistrationClinicalTrials.gov Identifier: NCT05297825

Unveiling the Epigenetic Impact of Vegan vs. Omnivorous Diets on Aging: Insights from the Twins Nutrition Study (TwiNS)

“…To investigate the impact of diet on the methylome, blood samples from a randomized clinical trial were used to quantify methylation (Landry et al 2023). As shown in Figure 1 , to quantify methylation, whole blood was collected to establish a baseline measure of methylation at the time of starting the trial (Week 0) and at the conclusion of the study (Week 8).…”

Possible roles of phytochemicals with bioactive properties in the prevention of and recovery from COVID-19

“…These phytochemicals are also included in beverages, such as teas from tea plants [10,21] and herbal teas. A recent study conducted with healthy identical twins has shown that those who were assigned to consume vegan diet had significantly improved cholesterol concentration, fasting insulin level, and body weight loss compared to those who were assigned to eat omnivorous food, indicating the effects of phytochemicals on several health conditions even among genetically identical twins [34]. The health benefits of fermented foods has also been shown [35][36][37], which not only affect gut microbiota by the probiotic lactic acid bacteria, but also can improve the health status of the person directly by their anti-inflammatory, antioxidant, and other bioactive properties.…”

University Students as Change Agents for Health and Sustainability: A Pilot Study on the Effects of a Teaching Kitchen-Based Planetary Health Diet Curriculum

“…There is a growing body of literature that proves the positive impacts of dietary changes to more plant-based diets, as suggested by the EAT-Lancet Commission [ 6 , 7 , 8 , 9 ]. For example, a Swedish study concluded that a high accordance of the individual diet with the PHD was associated with a 25% decreased mortality risk [ 7 ].…”

“…For example, a Swedish study concluded that a high accordance of the individual diet with the PHD was associated with a 25% decreased mortality risk [ 7 ]. In a recent study, Landry et al [ 9 ] showed beneficial cardiometabolic effects of plant-based vs omnivorous diets in identical twins. Springmann et al [ 8 ] analyzed the health and environmental impacts of different diet scenarios for selected regions in the world and showed that in high-income countries, the change to more plant-based diets, as recommended by the PHD, would lead to improved nutrient levels, a reduced risk of premature death, and the reduction of environmental impacts.…”