Reading the Headlines About Vegetarians and Depression is Depressing: The Media Response After “What The Health”
News flash. Self-reported dietary data derived from a group of men who had no idea what the definition of a vegan diet was were tested with a depression scale designed for postnatal women without any data on cholesterol and B12 levels. An association between vegetarian diets and depression was found. Headlines across the world are blasting out this news as if this was a prospective and randomized study. Nowhere in the media reports are comments on the major limitations of the dataset recognized by the authors. The media headlines ranged from “Vegetarians are more likely to be miserable” to ”Vegetarians more likely to be prone to depression” to “Vegan diet warning: this is why you should be eating red meat” even though there were so few vegans in the study that they were lumped into the vegetarian designation. A study of even larger size was published in 2015 showing an association of a pro-vegetarian dietary pattern with less depression. The headlines then were few and without the aggressive tone and scariness of this past week. Where was the headline about “Meat-eaters are miserable”? What’s up with the media and their apparent bias?
The study in question collected data on 9,668 male partners of 14, 541 pregnant women followed in England (why did nearly 5,000 men not participate?). They were asked to report if they were vegan, vegetarian, or non-vegetarians. Although hardly a joking matter in terms of the quality of the dataset, 72% of the self-reported vegans indicated current consumption of red meat. This important fact is buried in the discussion section, and never mentioned in the media reports, but this was clearly a confused group of men with no apparent understanding of what a vegan diet constitutes. In fact, the vegetarian cohort reported eating sausage or burgers in 7% of the respondents, meat pie in 10%, poultry in 12% and fish and fried food in over 50% of the men. Men responding as vegetarians had higher depression scores on average than non-vegetarians and an odds ratio (OR) of 1.7 was determined for a moderate or high depression score on the questionnaire. It can be questioned if an OR of 1.7 is even meaningful, at least in the view of author Nina Teicholz, who in her review of the movie What The Health, graded the scientific studies in the documentary with an ratio<2 as “too weak to be reliable”. Remember friends, Teicholz has a book to sell so knocking the film helps her sales.
Back to diet and depression. In 2015 the SUN project reported on a cohort of university graduates free of depression followed 10 years with food questionnaires and assessed for anew diagnosis of depression. The hazard ratios for a pro-vegetarian dietary pattern was 0.74, or a reduced risk of depression with the plant-predominant diet. In this study, dietary patterns were not self-reported but were assigned in a predetermined scoring method.
Other studies have shown less stress and anxiety in those eating a vegan diet, and in a prospective randomized trial of a nutrition intervention for 18 weeks, improved productivity at work was demonstrated with less depression and anxiety on a plant-based diet.
So are vegetarians really miserable? Should they start eating red meat? Should they be warned? Or is questionable science best taken in context of a large view of the data? Does most of the data indicate that a diet rich in blueberries leads to the blues? It is my view that the media bias to discount the health benefits of a plant diet is strong and pervasive. The initial response to the publication of the Presidential Advisory of the American Heart Association was greeted with headlines fairly accurate in capturing the scientific panel’s report followed by weeks of mocking the organization for commenting in one paragraph out of 25 pages on the value of coconut oil. The same wave has occurred in response to the movie What The Health. This documentary was greeted with positive press but the backlash to protect industry, authors, and sales of anything related to meat, eggs, and dairy is a fast and furious race that is still going on. For now, I will go on eating plants, expressing gratitude for my friends, patients, and colleagues who do the same, knowing that it is a path to health, preservation of the planet, and a vote to end the suffering of sentient animals forced to lead cruel and intolerable lives. All reasons to be happy.