There's a specific sort of fallacy about nutrition.

[conuly]

I first noticed it when Ana was little and her well-meaning kindergarten teacher didn't let her have Teddy Grahams because Ana was not having dairy and the Teddy Grahams had added calcium. The teacher was surprised to find out that calcium exists in other places than milk.

And, of course, we've all encountered people who profess not to know how vegetarians survive - those people believe protein only exists in meat and perhaps eggs.

Recently, I've spoken to three different people who stated definitively that oranges are the best source of vitamin C. One of them went so far as to claim that prior to globalization, everybody in Europe must have been suffering from a mild case of scurvy at all times! Point of fact, black currants are a much better source of vitamin C per ounce. Actually, the whole reason we evolved not to produce our own vitamin C is because vitamin C is everywhere in the foods our ancestors ate, and a great many foods are superior sources than citrus. So long as you occasionally eat something other than hardtack and gruel, your gums probably won't start to bleed.

I'm not sure how to formulate this fallacy, exactly, but I think the thought process behind it runs something like "There is one, and only one, optimal source for each nutrient, and if you don't eat that you'll get a deficiency disease and die".

Comments

[delphi]

I've run into this myself and still haven't been able to help my stepmother get her head around the concept of fat from non-animal sources.

To me, at least, it's always seemed a little bit like the phenomenon where people consider a dog or a mouse 'more' of a mammal than a bat or a rhinoceros. The categories of both animals and food are things we're taught very early in life, but usually pretty broadly. We then often extrapolate based on arbitrary traits instead of underlying structure because if we don't have a systematic understanding, our brains default to pattern-matching. So if someone sees an orange juice commercial at an early age that advertises that it provides 100% of your daily requirement of vitamin C, they'll find it easy to believe that things that look like oranges - other members of the citrus family - also have vitamin C. You might even be able to convince them that things that are similarly coloured and flavoured, like bell peppers or tomatoes, have vitamin C. But kale and broccoli? No way!

[conuly]

FAT from non-animal sources? Has she never heard of vegetable oil?

But kale and broccoli? No way!

Kale and broccoli are also not half bad sources of calcium, aren't they?

[kyrielle]

It took me _weeks_ to convince Andrew that orange juice supplemented with calcium and vitamin D has ... calcium and vitamin D. (He was worried about my bones because I cannot have dairy.)

Still working on convincing him that _other_ things do.

But he's eight...he has a bit of an excuse? Kinda?

[conuly]

If he or you are worried about your bones, even better than just diet is exercise, specifically, weight lifting. When you build muscle mass, you build bone mass, and you can tell him that. (Unless you don't intend to do this, in which case you shouldn't.)

LOL, or you could tell him about those poor kids detained in Japan during WWII whose teachers ground up eggshells and then spooned them into their mouths. Blech! I suppose it warded off rickets, but they all hated it.

[elenbarathi.livejournal.com]

"One of them went so far as to claim that prior to globalization, everybody in Europe must have been suffering from a mild case of scurvy at all times!"

What rot. Prior to globalization, everybody in Europe was eating turnips, cabbage, onions and rutabagas.

[conuly]

And parsley. And black currants. And dandelion greens, and nettles :)

Heck, even potatoes* have a decent amount of vitamin C in them, though they're not in the top ten.

* How far back are we pushing this? Are potatoes pre-globalization or post? Because if we go back far enough, I suppose most crops are post-globalization, because they weren't all domesticated in the particular part of Afro-Eurasia or the Americas we associate them with.

[elenbarathi.livejournal.com]

Oh sure, those foods were eaten seasonally where available, but essentially all of Europe ate cabbage, onions, turnips and rutabagas year-round, because they'll grow anywhere, and unlike fruit and greens, they'll keep over winter.

Apparently potatoes were the very beginning of globalization (http://www.smithsonianmag.com/history/how-the-potato-changed-the-world-108470605/).