A debate on science? An open letter to Garth Davis about science communication and unhealthy vegan diets.

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I received the following comment, I assume, from Dr. Garth Davis.

If this is Garth, great. If it is a troll, also OK, as this gives me the opportunity to fully discuss important issues about science communication and poor quality vegan diets.

For context, my disagreement with Garth started over the plant-based diet documentary film The Game Changers.

I have been very disappointed in the reception of The Game Changers by the plant-based community. I have a lot of respect for James Wilks–he is both well-meaning and clearly very intelligent–as well as many of the other people involved in the film.

However, there is very clearly a great deal of exaggeration in the film and of taking license with the facts to sell a story. This story gives the impression of benefits to meatless diets, especially with respect to athletic performance, that are not commensurate with a sober and impartial look at the evidence, and using means that misrepresent the facts. Layne Norton has provided a helpful overview of many of the important factual problems with the film.

However, these factual errors will not be the focus of this article. Instead, I will discuss what the role of factual errors is in scientific communication, as well as what I think the real problem with The Game Changers is: namely, that it poses a real risk of harm to the health of viewers who follow its advice by promoting a poor-quality diet.

Good Enough nutrition science communication

Some might excuse this problem with the film by arguing that switching to a healthy plant-based diet can and does have dramatic, positive health benefits for many or most people, even if the film does take some liberties with some of the facts.

According to this point of view, when talking to lay audiences, a precise representation of the facts is less important than a representation of the facts leading the audience in essentially the right practical direction.

In fact, precisely representing the facts might get in the way of representing the essential practical truth of the facts: being precise with the science might actually prevent one from telling a compelling and essentially true story that might be of benefit to audiences.

(The nuances of a strictly entirely true story, for instance, might be so complicated that they detract from the main point.)

This is a point of view that I struggle with all the time. And I think that there is some important truth to it. Ultimately I reject it as a starting point for science communication, though, for two reasons.

The harms of Good Enough science communication

First, powerful stories that involve misrepresentation of individual facts, even if that misrepresentation of individual facts leads to a “proper” representation of the big picture, eventually take on a life of their own and can be used for other purposes.

For instance, the insight that saturated fat intake is probably a dietary risk factor for cardiovascular disease can be conflated with fat phobia. This fat phobia, in turn, might be endorsed because it is “good enough” and leads to restriction of saturated fat.

This fat phobia, which is probably scientifically unjustified, then can be used by other interests to promote the idea that, so long as one does not eat fat, one will not get heart disease. Perhaps this is also “good enough” because it causes people to avoid saturated fat.

But, finally, this leads to endorsing high-sugar, low-fat products as “heart healthy”. Since they have little fat.

A story that was “good enough” over several permutations of “good enough” becomes counterproductive and harmful. What’s worse, this problem becomes entrenched in institutions of authority and a part of the orthodoxy and very difficult to change.

Exhibit A:

Honey Nut Cheerios Certified as “heart healthy” by American Heart Association

As I showed using a very basic risk calculator, while LDL levels, which are modified by fat and dietary cholesterol intake, are an important risk factor for cardiovascular disease, they are not the only risk factor modified by our food. If they were, then unhealthy plant-based diets, which do not contain dietary cholesterol or much saturated fat, would not increase risk of cardiovascular disease.

Yet, this breakfast cereal of clearly questionable nutritional value (nearly half of the carbohydrate content is from added sugar) is certified by the American Heart Association for the sole reason that it contains little saturated fat and dietary cholesterol.

Yet this is clearly at odds with current science, which shows that of all macronutrients analyzed, replacing saturated fat with carbohydrate and probably especially refined carbohydrate has a very modest impact on lowering LDL compared to other macronutrients. Substantial evidence suggests that refined carbohydrate might not be an improvement on saturated fat for lipids after all, and each might raise risk of coronary heart disease to an equivalent degree compared to other sources of energy.

Refined carbohydrates are associated with coronary heart disease to a similar degree as saturated fats

Yet because of the longstanding and myopic focus on saturated fat and dietary cholesterol–so long as it is low in each, it must be heart-healthy!–this distortion, this health-washing continues with the blessing of the American Heart Association. Dislodging this entrenched misinformation will be very challenging indeed.

This is why we must always insist on the facts and only the facts. Before we know it, our distortions have gotten away from us, and the story we invented is no longer the one that we control.

Good Enough science communication is a slippery slope that most certainly will be exploited by parties whose interests are not science. And there are many such parties. Science is fragile. Money is powerful.

Good Enough nutrition science communication may yield short-term benefits at the expect of long-term loss of trust

This leads to my second reason for rejecting the Good Enough point of view: it will produce short-term gains but for the reason I discussed above (and others), it will erode trust in science.

Not only will intelligent people see through the flimsy justifications for this or that Good Enough-based policy or recommendation or claim, but the unintended consequences will also lead to a loss of trust in science itself. Because while what was communicated was not itself science, it was portrayed as science; thereafter, science will be viewed with suspicion, for no fault of its own.

This will in turn impede scientific authorities’ future efforts in bringing about or guiding policy change that is consistent with science, which will be a great loss for everyone.

Scientists will come to be seen as having “agendas” and as selectively communicating the facts. This distrust will give rise to alternative sources of authority, who will themselves make the fanciful storytelling of the Good Enough storytellers look tame by comparison. Witness: the rise of the ketogenic diet and LCHF.

So I reject Good Enough and insist on strict adherence to reporting the facts. This is a substantial constraint in telling a good story, but not, I believe, an impossible one to overcome. So far, very few people in the nutrition science space have seemed to really try to do both. We seem to have so little faith in the truth.

The main problem with The Game Changers is that its message might harm substantial numbers of people

But even if I thought that the kind of science communication that distorts facts in service of communicating an overall “accurate” practical point of view was justified, would this apply to The Game Changers? I think not.

As I argued in this post, The Game Changers is a film that represents plant-based diets as healthier than omnivorous diets without respect to quality–in fact, mainly promoting poor-quality plant-based diets, presumably to appeal to the broad public.

Why The Game Changers risks harming the health of those who follow its advice

In doing so, the film not only does not use the means-ends reasoning that Good Enough science communication does, it actually risks harming viewers who follow its advice. This is why, from no point of view except, perhaps, a very ruthless kind of ethical or environmental veganism, can the information communicated in The Game Changers be justified.

Unless supplemented by explanations that whole foods are necessary to unlock the health benefits of plant-based diets, and that junk food plant-based diets are harmful to health (which would contradict the message of several key scenes in the film, as I document in my post), by no means can the film be justified or should it be endorsed by health professionals, whose professional obligation is to the health of human beings and not to the well-being of animals or the environment.

One debates opinions but discusses science

That aside, if this really is Garth, I would be glad to discuss this issue and others, but not to debate. The only positions that I have that are “set in stone” are principles. I think that we will broadly agree about both these and about what the science says.

Interpreting science is really just about reporting what the literature says. It is almost mechanical. While it is complicated in the details and while a priori philosophical commitments can affect how one “assigns weight” to different kinds of evidence… my belief is that reasonable people, if they invest the appropriate time and seriousness, will ultimately come to essentially agree on the details, strengths, limitations, etc. of what the current body of literature says. From this point of view, either a person is ideologically motivated and thus not a part of a scientific discussion and not worth seriously talking to, or they are not ideologically motivated and a discussion is possible.

Given the above, if a discussion is what you want, Garth, I am down for that. Let us arrange it.

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  1. I will comment, though you have shown that you have little interest in having interactions within your blog reply section.

    Your pattern of communication seems to tend to negativity.

    Game Changers attempts to get people on the standard American diet to start to examine their food choices. To examine their strongly held belief that meat and dairy are healthy, and plants are unhealthy – in terms of which paradigm provides the majority of calories. That is the purpose of the film. Not for researchers whom are already able to understand further complexities in choice. Yet, you write your review from your point of view, and then judge the film on your current understanding.

    The film has a limited number of minutes to persuade, thus has a limited number of premises to present.

    The vast majority of people whom will watch the film have a food lifestyle that is packaged from the supermarket or made to order from fast food businesses. The movie does not try to present the premise that it is better to start to eat whole foods, which involves a tremendous lifestyle change. Yet, you presume that this is the correct stage to judge the movie at, and your logical constructions are clearly from this premise.

    If you wanted to be helpful as a nutritional researcher and blogger, then write Game Changers 2. This would make it clear that people need to move from factory processed foods to whole foods.

    But unfortunately you have made a public stand, thus you are cognitively fixed and must therefore defend this position of being a reasoned critic of this movie. You are also unable to modify your view, which is in line with your pattern of detracting from the works of others, instead of adding to the works of those whom try to move people along in a spectrum of small changes over time.

    1. The purpose of the film is to encourage people to eliminate meat and eat a plant-based diet. This is not necessarily sufficient to improve people’s health. Some people who choose a plant-based diet might actually worsen their health by doing so, because it wasn’t specified what kind of plant-based diet people should eat, and a good amount of junky vegan food was promoted in the movie.

      I am actually eager to change my opinion publicly. It shows open-mindedness, which is something that I want to model. I have no problem being shown to be wrong.

      As far as my engagement, that’s true. Time limitations. I also sometimes do not respond to important emails. I cannot do everything.

    1. Avi is very smart, and I begged Joe not to have Chris on again, but he did not listen to me. Chris is not a credible writer on nutrition or health.

  2. “Unless supplemented by explanations that whole foods are necessary to unlock the health benefits of plant-based diets, and that junk food plant-based diets are harmful to health (which would contradict the message of several key scenes in the film, as I document in my post), by no means can the film be justified or should it be endorsed by health professionals, whose professional obligation is to the health of human beings and not to the well-being of animals or the environment.”

    And yet The Game Changers website does exactly that – it clearly points to whole foods plant based diet in a section” optimal health”.

    As for your graph on junk food vegan diets, it does not mean what you claim it does (which I pointed out in your previous post) and you if you truly want to follow the science then you have to admit we have no research to back the claim that either SAD or vegan junk food diet is worse. Obviously both aren’t optimal but even marginal improvement over SAD could save millions of lives globally.

    1. All the graph says is that not all plant-based diets are benign or healthful. TGC did not specify which kind of plant-based diet one should consume, opening the door for deteriorated diet quality upon switching to a PBD.

      One can make this concrete by looking at two particular food choices: fish and cheese. I think consensus would indicate that if fish or cheese were replaced by vegan junk food, e.g. hyperprocessed baked goods, disease risk would worsen, not improve.

      1. Kevin, I’ve missed the notification for new comment so have missed your reply.

        Yes, there is certainty that switching from fish to baked, white flour foods will worsen health. However, is that a realistic substition? In a sense, does that actually happen in real life? Do people switch from salmon to… some hyperprocessed good or would they rather switch from fish to maybe tofu – even if whole foods plant based is not their goal at all?

        What I’m trying to say is that I completely agree one can be unhealthy on plant based diet but I’m very curious how one to one plant based replacements for meat and dairy will change health outcomes of people eating standard diets, i.e. changing Whopper for Impossible Whooper, milk for soy milk, cheese for cashews cheese and yogurt for coconut yogurt etc. Would that make the diet better? If so, by how much?

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