Nutrition and Enlightenment Values

The Scientific Method in Nutrition & Dietetics

After uploading a video clip in which I mentioned that seed oils aren’t dangerous despite what some nutrition communicators claim, one viewer commented: “‘Seed oils are fine’ what? I can’t believe what I’m hearing. Avoid seed oils at all costs”. I replied with a link to my article The Exoneration of Seed Oils, in which I reviewed the research on seed oil consumption and disease risk. The individual replied: “Seed oils are ultra-processed oils that were originally used alongside petrol and diesel, you can’t seriously be telling me they’re good? Either you’re paid off to have this opinion or you’re no real nutritionist”. Like so many others, the guy was committed to his assertions with no desire to have his mind changed even when presented with overwhelming evidence demonstrating his claim to be incorrect. This recent example is far from unique: it’s typical of the way people adhere to what they learn from social media ultracrepidarians.

Humans are naturally inquisitive. It’s in our nature to ask questions about the things we experience. But the extent to which we fail to recognise our biases is one of our biggest flaws. Instead we resort to being led by our subjective feelings and emotions. We feel it’s so important to stand by our beliefs, that we adhere to our positions even when confronted by demonstrable evidence to the contrary. Moreover, when we stand by our beliefs – even in the face of irrefutable evidence that a belief is untrue – we’re often revered for doing so.

Nutritional Ideology

Few scientific disciplines invoke such an unashamed display of biases as nutrition and dietetics. This is demonstrated by the numerous dietary strategies that have been published over many decades, with each regimen having its proponents lined up ready to defend their nutritional ideology. Camps include low carb, low fat, keto, vegan, paleo, carnivore, high protein, carb cycling, juicing … I could go on! And, “ideology” is the right word: take a look at the number of social media accounts that include mention of the diet “tribe” to which they ascribe their allegiance – like “keto.james” or “melanie-the-carnivore” – proudly worn like badges of honour. Moreover, what makes this particularly hard to navigate is that each camp is able to present credible peer-reviewed evidence to back up its claims. How on earth are we expected to discern the truth? At the very least, we want to know if one dietary strategy is preferable so we can live long, healthy lives while enjoying our time performing to the maximum of our capabilities.

With so much misinformation, it’s scarcely surprising that people are confused about which foods are “good” and which are “bad”. The majority of the sub-quality information in nutrition policy results from inadequate standards in nutrition research. Nutrition science isn’t the clear-cut evidence-discerning machine we think it is, and, like any science – though arguably more so than most – it’s inherently flawed. I’m not merely talking about nutrition research that’s fraudulent, negligent or even biased in the fudging-of-numbers or p-hacking sense – although, sadly, this is also evident – more that it’s hugely hyped. Nutritional epidemiology – i.e. examining diet and nutrition in relation to health and disease – is difficult and incredibly nuanced. The psychologist and writer Stuart Richie, in his book Science Fictions: Exposing Fraud, Bias, Negligence and Hype in Science, notes that “An incredibly complex physiological and mental machinery is involved in the way we process food and decide what to eat.” Richie points out that observational data are prone to enormous bias, noise and the vagaries of the human memory, and trials can be tripped up by the complexities of their own administration. Indeed, he refers to nutrition science as “an extraordinarily hyped field” and goes on to point out that the reason for the extreme hype in nutrition is that “nutritional epidemiology is hard” (emphasis in the original) [1]. How many times have you been told about the latest nutritional fad? So-called “cutting edge” information in the media sells stories. Hype is a huge problem in nutrition; it feeds beliefs providing undue validity, adding further emotional bias to the narrative of a particular diet camp.

To some degree, this is understandable. If you’re reading this, you're (probably) alive. This means you (likely) acquire sustenance. So I guess the fact that you eat makes you an expert in food and nutrition and is why everyone has an opinion when it comes to what to eat. How, then, do we mitigate these biases? What tools do we have at our disposal?

Nutrition and the Scientific Method

Science is not limited to controlled experiments: it’s everyday life. Whenever you see an emotional assertion by someone on social media, ask yourself if the individual is being open minded. To stop yourself from being influenced by what you hear, seek to validate any claims. Are your own beliefs free from bias and based on the best available evidence? The scientific method provides the tools to self-check, helping to guard against biases born out of our beliefs. The premise of the scientific method is the application of rigorous scepticism about what’s observed, in the knowledge that humans are flawed, prone to assumptions and inclined to jump to conclusions. Features include Bayesian reasoning, Popperian falsification, peer-review and replication, among others. It involves the formulation of a hypothesis which can be tested and validated, and a theory can then be developed. A hypothesis is the supposition or proposed explanation of an idea with limited evidence and serves as a starting point for further investigation. Humans are prone to affirmation via confirmation bias: it’s intuitive for us to want our ideas to be right. A hypothesis must be falsifiable and the default mode of thinking should be to reject the null hypothesis: if it’s not possible to disprove the null hypothesis then it is likely that the hypothesis will be true. This is counterintuitive, as humans are susceptible to emotion-led beliefs: we have a natural inclination to believe what we’re told and to accept this version as true.

A theory is a set of ideas with a verifiable explanation as to why something is true, and requires three conditions: it must be testable, it should be validated, and it must have a demonstrable mechanism by which it can be described. It is the default assumption that something is true until it is either disproved or a better theory comes along, which might be never. A strong theory is a position that’s as close to proof as we should dare go. An example of a strong theory in nutrition epidemiology is that a regular intake of dietary trans fats increases the risk of cardiovascular disease. Numerous observational studies have shown a link between dietary trans fatty acid intake and increased risk of cardiovascular disease, and there’s a plausible mechanism by which they contribute to athlerosclerotic plaque formation [2]. Of course, albeit highly unlikely, the theory might turn out to be wrong and we could be missing out on these useful innovations.

Peer review is the evaluation of research by others who have similar competencies in the field in question. The peer review process is a form of self-regulation in order to maintain high standards and credibility. For the most part, the peer review process works well in that it serves to minimise bias in a paper’s results and conclusions. However, it can be slow, which delays publication and the propulsion of ideas. Also, as it involves human behaviour, it’s fallible, prone to corruption and subject to bias, and ideas can be stolen.

Science and Enlightenment Values

Enlightenment values involve reason and rationality through rigour and logic in combination with compassion for the flourishing of humankind. Reason is the conscious application of the mind to understand or make sense of things, and apply logic in order to make judgments, and to adapt or justify those judgements as required. Reason is the method for acquiring knowledge about reality. While making a reasoned judgement can involve emotions, we should recognise that they are merely emotions and acknowledge that they’re likely biased and should not be relied on. Reason allows us to further our understanding and to collate data into something meaningful, clear and definable within the appropriate boundaries. Rationality is the act of accepting reason as the supreme authority in matters of opinion, belief and behaviour. Rationality denotes that reason alone is the source of knowledge and is independent of experience. Rationality allows reason to be put into context. Logic is the process by which one accepts one proposition over others through the critical appraisal of arguments. It is the attempt to describe rules or norms by which reason operates in order for reason to be applied. Logic is the means of understanding that allows us to distinguish between what’s true and what’s false, so we can identify bad ideas and find the truth. Logic is the foundation of knowledge.

Intellectual rigour is the quality of taking care and being thorough. It is the process of maintaining strict consistency within certain parameters and is how we adhere to our values. When we’re rigorous, we take into account the entire scope of available knowledge on a topic and actively aim to avoid fallacies. Rigour requires a sceptical assessment of the available knowledge. An idea that has been dealt with rigorously has been dealt with in a comprehensive, thorough and complete way, leaving no room for inconsistencies. Although rigour involves both effort and work, putting effort into and working hard on an idea does not mean that one has been rigorous. It’s not that people are lazy or lack motivation, it’s that often they’re unaware of their biases and fail to cross-check their ideas. An anti-GMO activist, for example, may be highly motivated and spend a deal of time researching to back up his claims, but lacking rigour, he may fail to consider alternative viewpoints that could provide discerning evidence to annul confirmation bias. Intellectual rigour is care, consistency and effort for the acquisition of knowledge.

Compassion is to recognise the suffering of others and to take action to help. It is the ability to put one’s own concerns aside in order to see things from another’s perspective. It considers fairness, justice and the interdependence of others. Without compassion, our biases may result in us inadvertently overlooking the needs of others.

Intellectual honesty is the practice in which our convictions are kept in proportion to valid evidence and involves an unbiased approach to the acquisition, analysis and transmission of ideas. We are being honest when we, knowing the truth, state that truth, regardless of social pressures, and maintain to be as transparent as possible. Complete intellectual honesty may not actually exist as we may not be able to completely mitigate our biases. However, we should strive to be in the position of being honest whenever circumstances do not limit us. Intellectual honesty is the assertion of our beliefs through the adoption of reason and logic.

Being objective is the process of actively comparing our thoughts to reality and is the means of determining what’s true. It is the recognition of reality as the pinnacle of evaluation, and the acceptance that all knowledge is knowledge about reality. It’s a mistake to believe that an individual cannot be objective if she has a personal stake in a claim or idea. The implication is that emotion, motivation and circumstance manifest as biases and prevent us from being accurate. Since objectivity is the act of conforming our thoughts to reality, it should be clear that this is possible regardless of any influences. As we’re all fallible to our own biases, an objective thinker actively maintains to be mindful of her biases, rigorously attempts to keep them in check, acknowledges that she will frequently fail in doing so, accepts when she is wrong and is comfortable with correcting her position. There can be a degree of subjectivity when being objective, and this makes differences of opinion useful. We all have different lived experiences on which we base our ideas, and this is why it’s useful to disagree. When we’re being objective, we strive to minimise our biases and to view things honestly through reason, rationality, rigour, logic and compassion.

Enlightened Nutrition?

Self-sceptical by design, Enlightenment values evolve and this means that we won't always get things right, but they allow us to challenge ourselves, accept criticism, amend our behaviour and acknowledge progress. They allow us to see that knowledge is what we can learn about reality, and they encourage debate as a means of getting to the truth. Enlightenment values are self-correcting. It’s counterintuitive for humans to have their beliefs changed, and most people most of the time aren’t open to their ideas being flexed. Ideologues committed to their ideas – such as my seed-oil-hating troll – are unlikely to even be reading an article like this. However, if you've reached this point in my article, you might be the sort of person who is open to having their mind changed on most issues.

By now you may be wondering why a nutritionist is offering his layman perspective on Enlightenment values and how this relates to food choice. Well, because of the overwhelming amount of shoddy nutrition advice, a successfully influential nutritionist has to think more broadly than mere nutrition science and dietary advice. Maybe you can take something from this perspective and can be a little more attentive next time you’re scanning social media. You can be an influencer. I don’t necessarily mean of the social media ilk, but someone who, through being mindful and open to self-correction, challenges non-evidence-based assertions. Maybe next time you’re at a dinner party and you hear someone offering highly questionable dietary advice, you’ll be more vigilant to the lack of substance behind their claims and you’ll constructively challenge them. While it’s unlikely you’ll change their mind, you may well influence other party-goers listening in on your discussion. And it’s just possible that you might even sow a seed of doubt in the mind of the perpetrator, too.

References
1. Richie, S. (2020) Science Fictions, London: The Bodley Head, p169.
2. For example: (a) Willett, W. C. (1993) ‘Intake of Trans Fatty Acids and Risk of Coronary Heart Disease Among Women’, The Lancet, 341(8845), 581-5; (b) Shapiro, S. (1997) ‘Do Trans Fatty Acids Increase the Risk of Coronary Artery Disease? A Critique of the Epidemiologic Evidence’, American Journal of Clinical Nutrition, 66(S4), 1011-7s; (c) Mozaffarian, D. et al. (2009) ‘Health Effects of Trans-Fatty Acids: Experimental and Observational Evidence’, European Journal of Clinical Nutrition, 63(S2), s5-21.