Owen Yang
It is very difficult to imagine that food does not affect out health. But it remains difficult to produce a conventional solid scientific evidence on this. Now why would that be?
It is very difficult to imagine that food does not affect out health. But it remains difficult to produce a conventional solid scientific evidence on this. Now why would that be?
Hygiene, malnutrition, toxins, and obesity are big killers that has been a dimension of food
The argument of food has shifted over time when we found out what matters in food one by one in the history. We now know to minimise the bacteria or other micro-organisms, and toxins, and we eat food in a broad style to get at least some basic level of nutrients required to maintain body functions. We then identify that obesity is a big killers of longevity and quality of life. These should not been forgotten to be previously unknown as a dimension of food that can affect our health tremendously, but then become a separate topic after they are identified and become apart of our healthy life.
So the question of food tend to be ‘what is the next thing in food that is unknown to us that can affect our health’, and this is in itself a difficult question to answer.
When my mom asks me whether it is healthier to eat broccoli than to eat cabbage, I always say the first priority is to get calories balanced and avoid obesity, and then have a balanced protein, carbohydrates, fat, and fibre, and then start to think about more nuanced food style choices. In the majority of human life scenarios, we do not need to maximise our health by switching from broccoli to cabbage, or vice versa. Sometimes the nuanced option is just a better way for us to achieve the big goals better. For example, having low glucose-index food is good partly because it helps us to eat less and absorb less calories on average because we are less hungry with the same calories.
Measuring food items can be misleading but is the best thing we have got
Now we know smoking is detrimental to health. It increase risk of heart attack, cancer, and death. But can you imagine what will happen if we compare different brand of cigarettes and try to answer what it is in the cigarettes that is detrimental to health? You will find a relative equivocal results because of many reasons. Different cigarettes are probably quite similar in terms of health, and therefore comparing them and find a healthier one is just very absurd, although we find it absurd simply because now we know the reason. The difference between cigarettes can also be distracting. This is because perhaps the chemicals themselves do not bear the burden of health, but it is the fact that there is smoke and it does not matter too much what actually generates the smoke.
So in the cigarette case, we now know that we should be comparing those who smoke to those who do not smoke, and more precisely, those who breathe clean air.
Back to food, unless we know what is driving the food-related health outcomes, we are going quite blind. We do not know whether it is the component of food, chemicals in food, the frequency we eat food, the combination of food, or the combination of food and other parts of our life (say sleep or exercise) that is. So what we have been doing now is trying different methods to find a pattern. In other words, when you find eating beef is not too much associated with cancer compared to non-beef eaters, it could be because beef eaters has been compared to non-beef eaters who also have eaten something or have done something that can cause cancer.
The public interests argument
We are probably still adjusting to the ‘woke’ society in which scientists and doctors are not ‘authoritarian’ but should absolutely listen to the public. This can lead to something good, but so far I would say the world is adjusting, and some good science is inevitably adjusting out.
If you ask a member of the public what they find more important, they would probably say it is important to know whether eating beef can cause cancer, rather than whether a un-named dimension of eating behaviour can cause cancer. The topic that ‘makes populist’ sense is inevitably attracting the attention of the newspapers, and appealing to the public that is ultimately the one who contribute to the public or non-profit research fundings.
I conducted an analysis on whether ‘having been breast-fed as a baby could be associated with having cancer or not having a certain cancer when we achieve older ages.’ I spent quite a lot of time explaining the history of choices alternative to breast feeding, and emphasised it should be seen as the risk associated with these alternative options. I do not think anyone listens to us, and when I tried to rephrase the topic of cancer risks associated with not being breast-fed, everyone objected and say this is just not easy to understand.
The impossibility of doing experiments
Another layer on top is that food studies will probably stay as an observational study for most of the time. Therefore when some evidence is produced, the food industry can always hijack some ‘scientists’ who give generic comments on the weakness of an observational study.
