In a study recently published in the American Journal of Clinical Nutrition, researchers conducted an 8-week randomized controlled trial to evaluate the effects of consuming a plant-based meat analogue (PBMA) diet (PBMD) versus an omnivorous animal-based meat analogue (ABMD) diet (PBMD). Using linear mixed-effects models, the study of 82 participants found that effects on dietary fiber, potassium, sodium (all increased in the PBMD cohort), and dietary trans fat (increased in the ABMD cohort) varied by dietary exposure, but no significant improvements were observed in cardiometabolic health biomarkers (lipid lipoproteins).
Contrary to marketing promises and the authors' hypotheses, these findings highlight that PBMDs do not predict statistically significant cardiovascular health benefits compared to traditional ABMDs in the Asian cohort studied. Taken together, these results call for a focus on nutritional quality in future development of PBMAs.
Study: Plant-based meat analogs and their effects on cardiometabolic health: An 8-week randomized controlled trial comparing plant-based meat analogs with corresponding animal-based foods. Image credit: Antonina Vlasova / Shutterstock
background
Despite being omnivorous by nature, religious and cultural dictates have historically driven many geographically diverse human societies to consume a primarily plant-based diet (PBD). This trend is particularly evident in Asian and Indian regions, where some religious sects ask their followers to abstain from eating meat and meat products. In recent years, PBD has seen a resurgence in popularity globally, driven primarily by environmental, health, and animal welfare concerns.
Previous studies have established that vegetarian and vegan diets are healthier than meat-based diets (MBDs), especially in terms of cardiometabolism. Furthermore, large, data-rich controlled trials suggest that a gradual transition from an ABD to a PBD can reduce the risk of chronic non-communicable diseases. Coupled with the aforementioned growing global interest in PBDs, these results have spurred the invention and development of plant-based meat analogues (PBMAs). These foods aim to meet the ethical and health benefits of vegetarian/vegan foods while mimicking the sensory properties of meat-based foods.
Unfortunately, as PBMA is still a new introduction, scientific evidence regarding its health benefits is still very limited. Although some studies suggest a weight loss benefit from PBMA intake, the results for cardiometabolic risk are so far confusing. Furthermore, studies on the topic have been almost exclusively conducted on European and American cohorts, with a paucity of data from other parts of the world. Despite a genetic predisposition to metabolic diseases, Asians are notably excluded from the literature.
About the Research
In this study, the researchers hypothesize that replacing ABD with PBMD will lead to incremental improvements in cardiovascular health, observed in the form of a reduction in negative markers of cardiometabolic risk.The researchers tested their hypothesis in a publicly sourced (via physical and electronic advertisements) Singaporean cohort conducted at the Clinical Nutrition Research Centre in Singapore.Sample screening consisted of participants completing questionnaires regarding their lifestyle, food frequency and health history.
The inclusion criteria for the study were limited to Chinese men and women who were adult (aged ≥30 and ≤70 years), omnivorous (consuming at least 20 g of meat per day), had high blood glucose levels but were not diabetic, frequent smokers, and obese participants (BMI f ≥27.5 kg/m2 or waist circumference >88 cm). [female] or 102 cm [male]) were excluded from the analysis.
Selected participants had their height, weight, and waist circumference assessed using standard anthropometric protocols. Fasting duration (>10 h), blood glucose, and glycated hemoglobin were recorded using the capillary finger-prick method. After baseline assessment, participants were randomly assigned to either the ABMD or PBMD cohort. The 8-week parallel-design randomized controlled trial intervention involved participants gradually replacing their usual dietary patterns with either the animal- or plant-analog-based diet provided in the study.
“These included six types of frozen meals broadly categorized as 1) minced beef, 2) minced pork, 3) chicken breasts, 4) burger patties, 5) sausages, and 6) chicken nuggets, which were delivered periodically to each participant's home. Corresponding to this list, the PBMD group was provided with the following foods: 1) Impossible Beef (Impossible Foods), 2) OmniMeat Mince (OmniFoods), 3) Chickened Out Chunks (The Vegetarian Butcher), 4) Beyond Burger (Beyond Meat), 5) Beyond Sausage Original Brat (Beyond Meat), and 6) Little Peckers (The Vegetarian Butcher).”
The primary interest of this study was diet-related changes in low-density lipoproteins, with other known cardiovascular risk factors being secondary. Data collection included participants completing a 3-day food diary, collected every 2 weeks during the study period. This dietary data was processed to establish participant-specific macro- and micronutrient profiles and to confirm participants' compliance with the intervention. Serological tests were performed to measure plasma insulin and fructosamine concentrations. Continuous glucose monitoring was used to assess changes in cardiometabolic risk factors during the meal replacement.
research result
Of 213 participants screened at baseline, 96 met the study inclusion criteria and were assigned in a 1:1 ratio to either the ABMD or PBMD cohort. Over the next 8 weeks, 14 participants dropped out, leaving 40 PBMD and 42 ABMD datasets in the final analysis. Participants were predominantly female (61%) with a mean age of 59 years. Participants were healthier than the general population, with an estimated mean vascular age of 56 years. BMI differed slightly between groups at baseline (PBMD was approximately 1.3 kg/m2 higher than AMBD) and was corrected for with linear mixed models.
Dietary assessment revealed that both protein and saturated fat showed a time effect, with post-intervention values ​​being significantly higher than baseline. In contrast, a decrease was observed in carbohydrate intake. The increase in protein was most pronounced in the AMBD cohort, whereas decreases in cholesterol, sodium, and potassium were more pronounced in the PBMD cohort. Adherence to the study intervention was high overall, 87% in PBMD participants and 95% in ABMD participants.
Surprisingly, no effects on lipid lipoprotein profile were evident (LDL cholesterol, the primary measure of interest, remained unchanged). The Framingham 10-year CVD Risk Index could not distinguish between baseline and final measurements across or within cohorts, precluding measurable changes in secondary outcomes of interest. Weight and BMI similarly did not improve over the 8-week study; however, there was a net reduction in waist circumference in both cohorts over the course of the study.
Conclusion
In summary, this study failed to reveal statistically meaningful cardiometabolic benefits of substituting PBMD for ABMD in Asians, particularly Singaporeans. Contrary to manufacturers' marketing promises and the authors' only a priori hypothesis, the current generation of PBMD does not reflect the cardiovascular benefits of its constituent plant foods, likely due to the loss of essential nutrients during the processing of the latter to produce the former.
“…the assumed health benefits of consuming PBMDs may not be directly applicable to those consuming PBDs. However, this represents an opportunity and an impetus for the food industry to reassess the production of next generation PBMAs with improved nutritional properties and biocompatibility. With the current focus on organoleptic properties and sustainability, taking nutrition into account as well would be beneficial for both manufacturers and Asian and global consumers.”
Journal References:
Toh, DWK, Fu, AS, Mehta, KA, Lam, NYL, Haldar, S., & Henry, CJ (2024). Plant-based meat analogs and their effects on cardiometabolic health: An 8-week randomized controlled trial of a plant-based meat analog versus a corresponding animal-derived food. American Journal of Clinical Nutrition (Vol. 119, No. 6, pp. 1405–1416). Elsevier BV, DOI = 10.1016/j.ajcnut.2024.04.006, https://www.sciencedirect.com/science/article/pii/S0002916524003964
Source link
