And is the failure to do so a condemnable offense?
This is quite closely connected to the previous post on fat activism, in particular the worry that a large part of what drives nutritional problems is not a lack of willpower regarding eating habits, but some combination of a lack of knowledge, affordability or access to nutritious foods.
If a lack of will power is the cause of things like overeating, then the inclination is to say that this is a (moral?) failing, and that the person who makes it should be amenable to criticisms. If, on the other hand, one of the three other fialures identified above is the primary cause (or if some combination of those failures is the primary cause), then the blame seems to lie elsewhere. Let us consider them in turn.
What do you need to know in order to eat healthily? At the most basic level, something like the energy in/energy out equation seems fundamental. If you consume more calories than you expend, you will gain weight, if you consume less, you will lose weight. But for this information to be useful, you need to know what foods have what calories. This isn’t so hard for packaged foods, as most are required to have that information present. It is more difficult for grains, fruits, vegetables and other foods that do not come prepackaged. There is likely, I think, to be a knowledge gap here. Further, there is at least a concern that nutritional information guidelines do not adequate state servings per package. A chocolate bar marketed for an individual may contain multiple ‘servings’, leading the consumer to underestimate their calories consumed when they eat the whole thing.
The other half of the equation is more difficult again. To know how much you need to consume, you need an idea of how much you expend. This varies according to a range of factors, including the weight and body composition of a person and the extent of their physical activity. Guidelines are available, but provide at best ballpark figures.
Would this knowledge suffice? No. In addition to knowing the above, some more nuanced nutritional knowledge is required. What nutrients do we need, and in what proportions? How much fat, protein, carbohydrate ought I to consume, and when is it best to consume these? Does when I eat things matter? Big meals or small? Should I eat when hungry, or wait for set mealtimes? You might think that these are unknowable, or that in order to eat well enough, this knowledge isn’t necessary. But having the knowledge would at least positively correlate with eating more healthily.
A connected issue with knowledge is knowledge of preparation. Cooking is not something that everyone is comfortable doing. Some people are bad at it, others dislike it, and still more have never tried. If you do not know how to cook, then it becomes more difficult to eat healthily, as your options are reduced to buying prepackaged or preparation free foods, or eating out. In each of these alternatives, your control over your calorie and nutritional intake is reduced by comparison to preparing food yourself.
This is probably an easier criterion to analyse. In order to eat well, you need to be able to afford to purchase good food. Often, good food is expensive. It may be cheaper to eat takeaways than to buy and prepare a nutritious meal. In particular, good vegetables and fruits can be expensive, and they do not last as long as packaged foods.
In addition, a component of affordability is time. If you have the income to buy healthy food without the time to prepare it, then the income you have does not assist. Similarly, anyone with a heavy workload needs to make time to cook, which can be difficult.
I live in Melbourne. It is easy for me to access good, cheap fresh food. I also have the time to shop at markets rather than supermarkets, which reduces my food cost considerably. Not everyone has this luxury. A problem particularly prevalent in the US, but not, I am sure, exclusive to that country, is the issue of food deserts, areas in which access to fresh and healthy foods is severely limited. This problem is exacerbated by the issue of transporting large amounts of food for those who do not own a car. (Again, being childless and living only with my partner means that transporting days worth of food for 2 on a bicycle is possible, in a way that buying for a family would not be). So there is at least reason to think that some people would legitimately not have access to the food they require to eat healthily.
As it turns out, I think that someone like myself has probably the least excuse for poor eating habits. I have the requisite knowledge, the income, the time, and the access to healthy food, which means I have only myself to blame for failing to take advantage of this. People who lack any of these identified features would, I think, be absolved from blame in proportion to their lack.
Is this conclusion going to be useful? Well, it could help shape public policy. If we want to reduce the health concerns arising from poor nutrition, in particular, the increasing numbers of overweight and obese people in society, then good education, affordability for healthy foods, and increased access to them are all policy goals worth pursuing.