Why does this society eat bones?

Question

Animals eat bones but most human societies do not. I have a fictional modern society which engages in this practice, but what sort of history or culture would lead to it?

Objectively, there are health benefits that might be used to derive an answer

• There are lots of different minerals and other nutrients in bone, which is a multilayered part of any vertebrate's body.

Layer by layer, here is what is in bone:

• Periosteum: Mostly protein and phospholipids. Not much else. This is the membrane surrounding the bone.

• Compact bone: This would be the toughest part to digest because of hydroxyapatite. High calcium and phosphorus in this layer as well as some protein.

• Spongy bone: This would still be hard to digest but not as hard. There is hydroxyapatite here too but not as much and there is more fat. In the spaces within the spongy bone is bone marrow. This bone marrow is by far the most nutritious part of the bone. High iron, fat, protein etc. In fact per 100 grams of bone marrow, there is 25% of the iron your body needs. This may sound small since we only need single digit milligrams of iron a day but this is actually very significant since most foods have 2% of required iron or lower. Organ meats are the only animal products with higher iron than bone marrow. In both of these, Iron is predominantly in the form of Heme which is easily absorbed.

• Benefits to pregnant women: when I thought that my people should eat bone, pregnant women need more iron. So unless you either eat a lot of plants frequently(like every 1-2 hours), eat meat exclusively, less often(this risks heart disease though), or eat a mixed diet making sure to include bone marrow and/or organ meats often; you are likely to end up with Iron Deficiency Anemia while pregnant.

• Meat and high amounts of food increases nausea while pregnant.

• Extra calcium and phosphorus is needed to prevent osteoporosis in pregnancy.

However, carbohydrates, fat, and protein are in higher demand, especially protein and carbs. Bone isn't a particularly good source of carbs, so that would likely be supplemented with fruit.

So I was thinking that since pregnant women would benefit from eating bone, anybody except for infants and toddlers should have bone as part of their diet. But we generally do not.

So how would my society arrive at a practice of eating bone, especially for pregnant women?

Answer 1

I’ll answer from the point of view that it’s not a “natural” food for them, and indeed carries risk.

Note that in our own case of humans, we’ve become dependent on external processing of foods: look at our digestive system (and gut size) compared to a gorilla’s.

If they are “people”, they may already be dependent on making food suitable to eat. That means cooking, grinding, separating, etc.

Their oh-so-delicate gut can only handle cooked meat and bread now. So, the bones go into soup, or otherwise have the proteins extracted to make gelatin. Why are BBQ Ribs so appealing? We cook on slow moist heat to make the nourishing part of the bone come out and mix with the cooked meat. The spent rib, now only mineral, gets tossed to the dog.

If they need to harvest bones as a calcium source because they’re not getting enough elsewhere, then they’ll grind it up and add small amounts to bread.

That is, they’ll make it work.

Answer 2

It depends on the dietary habits: if they have the entire animal available (meaning they are hunters), why should they discard the meat and focus on bones? They can still use bones to make soups or the like, but not as main dish.

If instead they are more like scavengers, feasting on the remainings of other's hunt, than it makes more sense that they rely on bones as supply. But... feasting on a rotting corpse brings additional risks of diseases (which will kill you in days, not in years like heart disease), plus competition with other scavengers.