Discussion
reduction in blood pressure, cardiovascular disease
CVD, SECONDARY, CARDIOVASCULAR DISEASE
Here, we report the effects of replacing red and processed meat with the weight equivalent of mycoprotein based foods over two weeks, on markers of CVD risk in metabolically healthy male adults. We note that these observations are of a priori defined secondary endpoints in a study designed to evaluate measures of gut health, thus we caution the potential for type 1 error. Nevertheless, our observation that mycoprotein consumption elicits reductions in total (− 6.74%) and LDL cholesterol (− 12.3%) in metabolically healthy and relatively young British men are of value; these findings reinforce similar observations from a limited number of other relatively small intervention trials in different study populations. Notably, in two parallel feeding studies, using mycoprotein based test foods purposefully designed for the intervention, Turnbull et al. noted that, (1) 191 g daily mycoprotein for 3 weeks reduced both total (− 13%) and LDL cholesterol (− 9%) in 9 subjects with slightly elevated baseline cholesterol status [Overall, there is now consistent evidence across several, albeit small, intervention studies demonstrating that displacement of meat with mycoprotein decreases cholesterol [Whilst a definitive intervention study demonstrating that mycoprotein, independently of meat displacement, lowers cholesterol is still needed, there are several mechanisms that might explain the observed effect. (1) In a previous health claim assessment, an EFSA panel concluded that the hypocholesteroleamic properties of mycoprotein were simply a reflection of its TMAO is considered a marker of CVD risk [Thus far, three acute feeding studies have reported on the effect of consuming mycoprotein on glycaemic response in healthy volunteers. In particular, Turnbull et al. [We observed non-statistically significant, but potentially clinically meaningful trends towards reduced systolic and diastolic blood pressure with mycoprotein (− 4.11 mmHg and − 2.71 mmHg relative to the meat diet). The effects of mycoprotein on blood pressure has not been reported previously. However, a reduction in blood pressure may be consistent with a diet high in fibre, alongside the small observed reduction in waist circumference, and greater excretion of potassium and urinary nitrates relative to the meat arm.Strengths of this work include the use of a randomised controlled crossover study design, whereby the participants acted as their own control. A parallel design would have required much larger numbers and matching of characteristics to produce equivalent statistical robustness. The investigators were also blinded to the intervention, removing any chance of bias from the analysis. The mycoprotein and meat products included were not exclusively produced for the study and are readily available and consumed amongst the population, The intervention was based on a high but not unrealistic intake of meat amongst the target group, healthy young UK based men, thus the findings may be translatable and of particular relevance to those consuming high meat diets.Limitations of this work include that this was an analysis of a priori defined secondary endpoints in a study designed to assess gut health. Further, our study population was relatively young and comprised only healthy, male adults. Compliance was only assessed using a 1-day food record, this was primarily due to concerns over participant burden and was balanced against the fact that nutritional status was not a primary outcome, a more thorough interrogation of compliance might have helped explain why some volunteers responded better than others to the intervention.In conclusion, this work is timely in the context of the explosion of interest in meat substitutes and the push towards meat reduction for ecological and health purposes. It demonstrates in a real-world setting that substituting mycoprotein for meat improves biochemical markers of cardiovascular disease risk. Further work is needed to evaluate dose response as part of normal dietary patterns and to elucidate mechanisms behind the observed responses.