Marrow  is great and all, but what about the bones that aren’t blessed enough to bear the sacred gel in easily extractable amounts? We can’t forget about those. Chicken backs, beef knuckles, ham hocks, chicken feet, lamb necks, hooves and any other animal-derived matrices of calcium phosphate and collagen fibers are all worth saving, cooking, and perhaps even eating. Hell, I bet elk antlers would make a fine, mineral-rich soup. The best part is that bones, feet, hooves, heads, and connective tissues are all pretty inexpensive, sometimes even free, parts of the animal. They also represent an entirely different realm of nutritional content than basic muscle meat, being complex organs playing multiple roles in the body.
You see, bone is living tissue, rather than inert structure. It is rigid, true, but it’s actually an organ, in fact, placing it squarely in the nutritional all-star camp of liver, heart, brain, kidney, and sweetbreads . Bone is also slightly elastic, owing to the collagen, which combines with the calcium phosphate to lend “elastic rigidity.” (If it weren’t for the collagen, bones would simply be hard with no give, and thus brittle.) Bone is full of minerals, mostly calcium and phosphorus (seeing as how the “bone” part of bone is calcium phosphate, this is no surprise), along with sodium, magnesium, and other trace minerals. If the connective tissue – and most animal scraps and bones you use will have tendons, ligaments, and cartilage – is still attached, bones also include stuff like chondroitin and glucosamine, popular joint supplements that are the raw materials for bone and cartilage formation.
Let’s do a quick rundown of all the other good stuff found in bones and, therefore, well-made bone stock:
- Bone marrow – We went over this last week , but I’ll say it again: bone marrow is one of the first “superfoods” (for lack of a better term – I actually slightly cringe using it) our ancestors enjoyed. It’s fatty, with a bit of protein and loads of minerals. Even if you’re cooking spindly chicken bones, there’s going to be marrow, and that marrow will make it into your stock.
- Collagen and gelatin – Most commercial gelatin comes from animal collagen already, so why not cut out the middle man and get your gelatin directly from bone and cartilage? The more collagen your bones have, the more gelatinous, rich, and viscous your stock will be – important qualities, especially if you intend to reduce your stock into sauces. Gelatin may even reduce joint pain in athletes , as one (admittedly small) study appeared to show. Another showed benefits for ulcer patients .
- Glycine – Although our bodies already produce plenty of glycine, rendering it a non-essential amino acid, there’s some evidence  that supplementation can help mitigate free-radical oxidative damage in rats with alcohol-induced hepatotoxicity. Bone broth is rich in glycine. It probably doesn’t mean much, but it can’t hurt. And hey – it may even improve sleep quality , as one Japanese study showed in human subjects. Drink a warm cup of broth before bed, perhaps?
- Proline – Proline is another non-essential amino acid found in bone stock, but supplementation has shown promise in patients suffering from vision loss due to gyrate atrophy . It’s also an important precursor for the formation of collagen, though it’s not clear whether eating proline has any affect on the body’s ability to make collagen.
- Hyaluronic acid – Hyaluronic acid, also known as hyaluronan, is one of cartilage’s three glycosaminoglycans. It helps broth gel, and it’s been used for years to treat race horses with osteoarthritis, usually as an intra-articular injection or IV fluid. Recent studies on oral administration  have been promising, though, meaning oral administration of quality bone stock (as opposed to, um, what other method of administration?) might help us with our joint issues, too. According to Wikipedia, human studies are underway and showing promise, but I wasn’t able to dig up much beyond this small study . Still, it’s compelling, and I’ll continue to drink broth regardless.
- Chondroitin sulfate – Chondroitin sulfate is another glycosaminoglycan present in bone stock. It’s also a popular supplement for the treatment of osteoarthritis the efficacy of which has come under question. One recent review  concludes that chondroitin sulfate “may interfere with progression of osteoarthritis”. I’d say it’s worth a shot.
- Calcium – I’ve downplayed the importance of large amounts of supplementary calcium  in the past, but that doesn’t mean it’s not important. It’s the raw material for bone production and fortification, and bone stock might be one of the best sources of calcium around, especially for those who avoid dairy and don’t eat enough leafy greens.
- Phosphorus – There’s also a good amount of phosphorus in bone stock, though I doubt Primal eaters lack adequate dietary phosphorus (there’s plenty in meat). Still, it’s a nice buffer.
- Magnesium – Magnesium is pretty lacking in the modern diet. Fatty fish like mackerel  offer good amounts, as do leafy greens , nuts , and seeds , but most people, Primal folks included, could stand to take in more magnesium. Dr. Michael Eades says  if he had to recommend just one supplement, it’d be magnesium; Dr. Stephan Guyenet over at Whole Health Source recently posted a couple great pieces, one on magnesium and insulin sensitivity  (short version: the former improves the latter) and another on magnesium and vitamin D metabolism  (short version: the former affects the latter). Bone stock is just another way to obtain this valuable mineral.
- Sulfur, potassium, and sodium – Stock has these minerals in mostly trace amounts, but they’re all important for health. Sodium  isn’t really an issue for most people, but potassium is undoubtedly important and often lacking. Both are crucial electrolytes (bone broth – possible new sports drink?). Sulfur is the “S” in MSM, or methylsulfonylmethane, the popular joint supplement that has shown some promising results  in humans.
The best way to extract all that boney goodness from the bones is to cook with them, and that means making stock (or broth; from here on out, I’ll just say stock, but the two are pretty similar, with broth technically being derived from meat and bones, and stock from just bones). I mentioned a basic chicken stock recipe  last year, but we can do better than that. Besides, different bones require different considerations. A few tips:
- Add a couple shots of apple cider vinegar to your stock. This aids in the extraction of minerals without really altering the flavor.
- Roast your bones beforehand. This adds color and flavor. For big bones like beef, 375 degrees Fahrenheit for 50 minutes usually works. For chicken, just use roasted carcasses.
- Don’t throw bones away. Even if you just ate a couple bone-in chicken thighs, save those measly little bones! Freeze them and keep adding to your collection until you’ve got a respectable amount.
- Don’t be afraid to simmer long and slow. Smaller animals require less cooking time to extract nutrients, so chicken can probably go for twenty hours and produce a quality stock, but beef or lamb bones can go for several days, provided you keep the heat low and watch the water level to prevent burning.
- Add feet, especially chicken feet, for added collagen – and more gelatin.
- If it’s a delicious joint supplement you’re after, look for actual animal joints to throw in. Knuckles, especially, have tons of cartilaginous material and snappy ligament that will break down in the water.
- When dealing with the bigger bones from ungulates, sometimes the heat and the water need a little assistance. To really get the good stuff, stick the bones in a sturdy bag and smash them with your sledgehammer (you do have a sledgehammer , right?). Then put the shards in the stockpot. Native Americans used to do this to buffalo bones  to get at the little grease pockets lurking within the bone latticework; why shouldn’t we do the same? Another option is to remove the bones after half a day or so and go to work with a smaller hammer, a chef’s knife, or even the food processor. They’ll have softened considerably, and you’ll be able to chop them up into bits for quicker, more thorough extraction. Last week, I took a 10-inch chef’s knife to some cow knuckles and cow necks that’d been simmering for a day and returned the pieces for another few hours of cooking. That stock was the thickest, richest, most gelatinized stock I’ve ever made. Correlation, causation? I lean toward the latter. In fact, going forward, I plan on doing this every single time I make stock. The difference was just that huge.
- You can eat bone, technically. Now, if you’ve made a proper stock and gotten all you can out of your bones, eating them may not confer many benefits. Still, it’s an interesting thought. Chicken bones in particular become pretty delectable after a day of stewing, and I’ll confess to sifting through the stock solids for snacks. I haven’t eaten an entire carcass or anything (yet), but I may try a few of the smaller, softer bones as an experiment. Anyone else?
- Once your stock has cooled in the fridge, only skim the fat if you’re prepared to store or use the stock right away. That layer of fat is protecting your broth from adulterants, whether they’re random fridge flavors or bacteria.
- Speaking of fat, I’d toss poultry fat. It’s a relatively high-PUFA animal fat, and a day of simmering has probably damaged it beyond repair. If you’re stewing bones with more saturated animal fat , though, you should absolutely save the fat layer.
- Veggies are optional, but tasty. They add flavor, and the classic mirepoix blend of carrots, onions, and celery is always a welcome addition. Herbs work well, too. I’m partial to thyme, bay leaf, and whole peppercorns, with maybe a sprig or two of rosemary added. If you’re doing herbs and veggies, add them toward the end of cooking, especially if you’re doing a marathon two-day stock making session.
Divining the nutritional details of traditional foods like bone stock and bone marrow is difficult, if not impossible altogether. We know stock contains gelatin, calcium, phosphate, magnesium, glucosamine, chondroitin, and other trace minerals, but what are the numbers? We’re a numbers generation; we expect to have accurate info at the tips of our fingers at all times, but that’s unrealistic. Bone composition isn’t set in stone. What the animal ate, how it lived, where it lived, the mineral content of whatever it ate, the nutrient density of whatever it ate – these all factor into the composition and content of the bones, joints, and cartilage. The nutrition facts of commercial bone meal  marketed as a calcium supplement gives us a general idea of the mineral content (900 mg calcium, 360 mg phosphorus, 9 mg magnesium per serving) of bone stock. That stuff comes from powdered “cattle raised in the United States,” which undoubtedly means corn-fed, nutritionally-deficient cows. We don’t know exactly how an animal’s diet affects its bone composition, but we know that it matters. Diet plays a huge role in everything, and I’d bet that grass-fed (again, as always) results in better, more nutritious stock. Regardless of the numbers, bone stock is good for you, damn good, and being somewhat in the dark about the precise nutrient count shouldn’t dissuade you from making and using your own bone stock on a regular basis. (If you don’t have access to bones from animals raised in the conditions you’d prefer—or you want backup broth for when you can’t make your own, you can find good stock available online .)
Even if you don’t (or are unable to) seek out bones specifically for cooking, you’ll end up with plenty as leftovers. In fact, I’d suggest opting for whole animals or bone-in segments; the meat tastes better, it stays fresher longer, and you get some cooking bones when it’s all done. When you roast a chicken, you’ve got an entire skeleton to work with. When you cook a bone-in leg of lamb on the barbecue, you’ve got a big femur left over. What does a skinless breast offer after it’s been eaten, or an endless parade of steaks? I love a good steak as much as the next man, but a Primal eater shouldn’t live on muscle meat alone. I highly recommend giving homemade stock a try. If you eat animals, you should have access to their bones, and you should never throw those bones away.
Have I missed anything? Anyone have any good stock-making tips?