Netflix documentaries are at it again!
This is a review of the recent ‘Game Changers’ documentary from Netflix. If you haven’t seen it, don’t worry you’re not missing out on much. There is a lot of cherry-picked evidence, anecdotal stories, and studies taken out of context inside of it.
That will be the point of this blog, to include a balanced scope of the current research we have available to us, I am not going to be biased against veganism, I’m just going to present the data we have. If you want to stop eating animal-based products for ethical reasons, you have my full support. Just don’t be misled into believing there are superior health benefits to it.
Vegan Diets For Health
We cannot deny the health impacts of increasing your plant consumption, to do so would be ridiculous. Eating plenty of fruits, vegetables, whole grains, beans, legumes, etc. etc. have numerous health benefits. A lot of these benefits come from the fibre, Anderson et al (2009), but a lot also comes from the vitamins, minerals and phytonutrients (nutrients only found in plants).
Vegetarian and vegan diets outperform meat-eaters in many observational studies when it comes to health markers and rates of disease/death, but these cannot be conclusively drawn to be down to the diet alone. Observational studies cannot by nature take into account the variables that exist outside of diet alone. These being exercise frequency, smoking, sun exposure, overall diet quality, social and financial health etc. etc. All of these factors will affect an individual’s likelihood of a disease or ill-health consequence (Key et al. 1999).
People who become vegetarian or vegan will most of the time start eating a lot of vegetables, fruits, and whole grains. If, before this diet, they were eating a bunch of junk food, then they will. of course, see health benefits. This has less to do with the fact they’re not eating meat and more to do with the fact they’re eating less trans fats and eating more nutrient-dense foods.
The documentary talks at one point about meat causing ‘cloudy’ blood and high triglyceride levels compared to plant-based meals. This little test is taken completely out of context and doesn’t describe the differences in the macronutrients consumed by the participants. If you eat fatty food (like beef or fried chicken) then your blood will contain triglycerides in it shortly afterwards. This is because you’ve just eaten fat, and your body needs to store it in its respective areas. If you ate something high in carbohydrates your blood sugar would shoot up, this doesn’t automatically become an issue and cause diabetes because it’s about to be stored. As always, context and the overall diet matters more.
Is There A Perfect Diet For Humans?
The JISSN declared in a position statement in 2017 that all diets that controlled for calories are equally effective at weight management and health outcomes. They compared all known diets and ways of eating in a systematic review and concluded: “A wide range of dietary approaches (low-fat to low-carbohydrate/ketogenic, and all points between) can be similarly effective for improving body composition” (Aragon et al. 2017).
Katz and Miller in 2014 declared that “A diet of minimally processed foods close to nature, predominantly plants, is decisively associated with health promotion and disease prevention” and that direct diet comparisons would be unlikely as each one biases their own benefits.
We also have to consider the ‘blue zones’ which are parts of the world where the communities have the lowest disease rates and longest life expectancies. None of these places are vegan but they do eat a lot of plants.
We have plenty of evidence to conclude that eating animal products is not only a safe behaviour but has health benefits as well. James Krieger has written such a fantastic review on dairy foods that to attempt to re-write here would be silly, check that out here: https://weightology.net/stop-ditching-the-dairy/.
Animal meats contain high-quality protein (with full amino-acid chains) that are shown to be beneficial for muscle building, retention, and overall health. Yes, you can get protein from vegan diets, but it becomes harder unless you supplement or are very clever with your food combinations. In the documentary, they compare 1 cup of lentils to 3oz beef and say you can get the same levels of protein.
Although these sources do contain the same amount of total protein, they contain different amounts of the amino acid leucine, which is vital for building muscle, more of that in a moment. Beans/lentils also contain a ton of carbs and fibre, making it harder to get to a decent total protein intake without skyrocketing carb levels, and therefore, calorie levels as well.
What we do need to take into account is the fact that vegans will naturally find it harder to get adequate VitaminB12 in their diets (as this is found in primarily animal products) and as such will need to supplement with this vitamin. Already a knock against its claims to be ideal for human health if it’s unable to provide all essential vitamins and minerals. Most vegan athletes also have to supplement quite heavily with protein and creatine, which we’ll address now.
Vegan Diets For Performance
Now, there are a LOT of athletes who perform at a high level who endorse this documentary and even feature within it. Again, the context of their overall diet matters more than just the fact they are plant-based. I don’t think any of them are experiencing better performance now than when they were omnivorous.
We do have Arnie claiming his health markers improved, but again, is this down to cutting out meat completely or a more balanced fatty acid profile? We know that eating too much saturated fat (in the expense of not balancing out with mono and poly-unsaturated fats) skews the fatty acid ratio and can then lead to increases in CV and heart disease (although these are observational/correlational).
Craddock et al 2016 found that: “Consuming a predominately vegetarian-based diet did not improve nor hinder performance in athletes. However, with only 8 studies identified, with substantial variability among the studies’ experimental designs, aims and outcomes, further research is warranted.”
Protein is vital for building muscle, right, we know that. But what many people are unaware of is that it is leucine, one of the amino acids, that stimulates muscle recovery and building in humans. We need enough leucine in a meal in order to promote the act of muscle protein synthesis. Plant-based protein sources are typically lower in leucine than animal sources, meaning you have to consume more of them to reach the same level of leucine required to stimulate muscle growth.
How much leucine do we need? Reidy et al (2016) concluded: “There were no differences in strength or mass/muscle mass on RET outcomes between protein types when a leucine threshold (>2 g/dose) was reached.” Meaning that 2g dose per hit is what we need in leucine. What is this in plant-based products you ask? See attached photo on the right (click save if needed).
You can see that the leucine content is far lower in plant-based proteins, meaning you’ll need more of them to stimulate muscle protein synthesis. This then drives up the calories you’d be eating, as discussed earlier. Vegan athletes may need to think about supplementing with vegan protein and/or leucine to optimise this process. The research on gaining muscle shows us that stimulating muscle protein synthesis 4-6x per day every 3-5 hours is optimal, Bohé et al (2001).
In terms of total protein needed, the general consensus from the evidence-based practitioners is somewhere between 1.4-2.4 grams per kg of bodyweight depending on your sex, activity level and type of training (endurance vs sport vs bodybuilding for example). This is tough, though not impossible, on a plant-based diet. Especially if you’re relatively small, inactive, but train often and are trying to lose body fat (and so are controlling for overall calories).
Of course, there are plenty of studies that conclude that vegetarian/vegan diets provide ‘no difference’ in performance. That’s the key phrase: ‘no difference’, not ‘better’, or ‘worse’. Lynch et al. (2018) concluded: “Given the sparse literature comparing omnivore, vegetarian, and vegan athletes, particularly at the elite level, further research is warranted to ascertain differences that might appear at the highest levels of training and athletic performance.”
Further research is warranted…
I think we can safely conclude we know that eating more plants is a great idea on many many levels and that eating less junk food is also a better decision, but the arguments of veganism being better for health and performance than others just aren’t there.
If you want to do it for ethical reasons, absolutely go ahead, but do not worry about it being ‘better for you’ than a balanced, omnivorous diet.