Despite some initial skepticism, I recently decided to dive into a new Netflix docuseries called “You Are What You Eat”. I had a hunch it might be pushing a certain agenda, but wanted to give it a fair shot before passing judgment. And while there were certainly aspects I appreciated, it soon became clear that this series had a strong bias towards promoting a vegan lifestyle.

As I watched, it got me thinking…how can we tell if a documentary is giving us the real deal or just trying to sell us a story?  Although there were some truths contained in the series, overall I felt it contained a lot of harmful fallacies. Using this series as a case study, I want to delve into how we can approach documentaries like this in the future and what to look for in determining bias and the validity of the viewpoints presented.

About the Study

The documentary is based on an 8-week study (published in November 2023) that put 22 sets of genetically identical twins on opposing (but healthy) diets: omnivore and vegan. The subjects were given their meals for the first four weeks and had to prepare their own meals during the second 4 weeks.

Essentially, they took a whole bunch of measurements to determine the participants’ cardiometabolic health before the study started and then again after the eight-week period was up (with the goal of hopefully being able to tell us that a vegan diet is far superior). 

This documentary serves as an extension of this study. They followed a few sets of twins as they went through the eight week period and they did a few additional measures that weren’t included in the study that was initially published. 

While the original study focused on parameters like blood lipids, cholesterol, glucose, insulin levels, vitamin B12, and body weight, the documentary delved into areas such as microbiome analysis through stool samples, telomere length assessment (a marker of biological age and longevity), body composition analysis, and VO2 max measurement. (They even looked at sexual arousal in women as well – kind of funny they were trying to sell a vegan diet by saying you’ll be more amorous if you eat more plants…!)

Problems with the Study

From a scientific standpoint, there are several glaring issues with the methodology used in this study.

1. Lack of Long-term Follow-up: One major concern is the short duration of the study. At only eight weeks in length, it fails to provide any insight into the long-term effects of the dietary interventions. There was no follow-up to assess whether participants were able to maintain their assigned diets beyond the study period or if any changes observed were sustainable over time.

2. Methodological Flaws: Additionally, the study’s design raises questions about how it applies to real-world scenarios. During the initial four weeks, all meals were provided, creating an artificial environment that does not accurately reflect the challenges of everyday life. There’s also a lack of information about the participants’ adherence to their diets during the self-preparation phase, making it harder to interpret the results.

3. Bias Towards Healthy Diets: This wasn’t just a vegan diet versus an omnivore diet. This was a healthy vegan diet versus a healthy omnivore diet. And one thing I know is that when we start to put labels like this on things, it really changes the milieu. So if you’re thinking that you’re just going to go vegan based on what you’ve learned in this documentary, but choose to eat a lot of processed vegan type foods, you might not have the same results that the vegan twins had in this study.

4. Confounding Factors: The inclusion of personal trainers for all participants introduces a confounding variable that muddies the interpretation of results. Without isolating the effects of diet from exercise, you can’t really attribute any of the observed outcomes solely to dietary changes.

Misleading Narratives and Fallacies

Beyond the shortcomings of its methodology, the documentary also perpetuates misleading narratives and fallacies that undermine its credibility.

1. Overgeneralization and Hyperbole: The documentary makes sweeping generalizations and exaggerated claims. For example, one of the experts states that the number one cause of death in the US is the American diet. But if you look at any statistical source on this, heart disease is always at the top of the list. Does diet contribute to heart disease? Of course. But many things contribute to the development of heart disease, not just the diet. So to say that it’s the diet that’s the number one cause of death is completely unsubstantiated. 

2. Fear-mongering Tactics: The documentary relies on fear-mongering tactics to vilify meat and dairy products, painting them as inherently harmful. By instilling fear and guilt in viewers, it attempts to sway opinions towards a vegan diet. 

The problem with this fear-mongering approach is that it makes you feel bad about what you’re eating. So they’re essentially trying to shame you into eating a vegan-based diet. And we know that shame doesn’t ever result in lasting change, and it certainly does not empower you to eat more plant-based foods. 

Of course, we know that including more fruits and vegetables and whole grains in your diet is good for your health. Nobody is going to dispute that. But saying that eating any meat or dairy foods makes you a bad person is dirty play as far as I’m concerned because and is really contributing to the diet culture fallacy that places moral value on food. 

3. Distorted Imagery and Language: The documentary used a lot of very disturbing imagery and language to talk about agricultural practices, making you feel dirty and immoral for even considering eating meat. They talked about how, every time you eat a hamburger, another tree gets chopped down in the Amazon forest, for example. 

It’s true that some of the animal husbandry and animal agriculture practices that we have are resulting in deforestation and other problems for the environment. But this doesn’t give anyone the right to shame you for eating according to your preferences, what you can afford, and what’s available to you where you live.

Missed Opportunities in Addressing Social Issues

The documentary talked about “food deserts,” which are places where it’s hard to get healthy food, especially in poorer and more racialized communities. While it was good they brought this up, they suggested that processed vegan foods could fix the problem, which is absolutely not the solution and may even contribute to the economic and social disparities in these communities. 

They also touched upon some of the other aspects of food that are important, such as what’s culturally important to us. This was a beautiful opportunity to talk about important social issues but instead, they missed the mark on it and chose to focus on how they can give the same foods to you in a vegan format.

Results of the Study

The study revealed some interesting findings, but they come with a few caveats. First off, the vegans saw a drop in their bad cholesterol, which is good news. However, they also had a decrease in their good cholesterol and an increase in triglycerides, which isn’t so great. So, when it comes to cholesterol, it’s a bit unclear if a vegan diet is really beneficial.

Additionally, the vegan group showed lower fasting insulin levels, which is a positive sign. But it’s worth noting that there are other ways to achieve this besides going vegan, like eating carbs with protein or fat, or being physically active. So while it’s good news, it’s not the only way to improve insulin levels.

Both groups lost weight, which isn’t surprising given the healthy diet and personal trainers they had. However, the vegans lost more muscle mass, which is really important for our metabolism, our bone health, and many other reasons. Losing weight at the expense of losing muscle mass is not necessarily beneficial for our overall health.

So these findings should definitely be taken with a grain of salt, especially when we consider the limitations of the study we’ve talked about so far, including the fact it was small, short-term, had no follow-up, and primarily focused on females. 

Approaching Future Documentaries

What we can learn from this documentary is how important it is to be discerning about the information presented and how much of the messaging you want to internalize and take on in your own life. 

Here are some key points to consider:

1. Follow the Money:

One of the most crucial aspects is to examine who funds and supports the documentary. In the case of this documentary, both the initial study and the film were funded by the Voigt Foundation, which has ties to promoting a vegan agenda. Additionally, some experts featured in the documentary are financially supported by Beyond Meat, a vegan food company. Understanding the financial interests involved can shed light on potential biases.

2. Evaluate the Message:

Consider the overarching message and agenda of the documentary. Does it present a balanced view, including dissenting voices and counterarguments? In this case, the documentary heavily promoted a vegan diet without acknowledging potential drawbacks or presenting opposing viewpoints. Lack of balance and reliance on unsubstantiated claims should raise red flags about the credibility of the documentary.

3. Unanswered Questions:

Reflect on the questions left unanswered by the documentary. Are there gaps in the information provided or aspects that were not adequately addressed? For example, I still had lots of questions about B12 levels, the specifics about the microbiome, and felt they ultimately glossed over a lot of the results of this study (probably because it didn’t definitively show that a vegan diet was superior!). To be clear, I actually prefer to eat a predominantly plant-based diet myself. While this works best for me, I do not feel that it’s best for absolutely everybody. And despite the fact that there are a lot of reasons why I think a plant-based diet is superior for me, I still thought that this docuseries was a load of BS! So I hope that by considering these factors,  you can start to approach documentaries with a more critical mindset, feel more able to judge the validity of the information presented, and make more informed decisions about its implications.