Actually it's not just one, this stuff is all over the internet: https://thetab.com/uk/2017/02/16/vegetarians-unhealthy-mentally-disturbed-says-new-research-33067 https://www.acsh.org/news/2017/11/10/vegetarian-men-are-more-depressed-are-steaks-treatment-12129 https://www.nytimes.com/2017/10/02/well/eat/good-vegan-bad-vegan.html https://paleoleap.com/vegetarianism-bad-environment/ https://www.alexfergus.com/blog/8-proven-reasons-why-vegan-and-vegetarian-diets-easily-ruin-your-body https://www.thehealthyhomeeconomist.com/vegetarianism-is-not-healthy/ https://sciencebasedmedicine.org/vegan-betrayal-the-myths-vs-the-realities-of-a-plants-only-diet/ https://www.westonaprice.org/health-topics/abcs-of-nutrition/twenty-two-reasons-not-to-go-vegetarian/ https://www.sciencealert.com/vegetarian-and-healthy-diets-may-actually-be-worse-for-the-environment-study-finds ...all mentioning research that says vegan/vegetarian diets are either no better (or worse) than the omnivore approach, or debunking the other claims of the anti-meat crowd. The above is just a small sampling, found in under ten minutes of searching....plenty more where this came from.