I’ve been writing about bone broth for a long time. I’ve been drinking it even longer. I’m not sure you can get anything much more primal than a heap of bones cooked for hours into rich, gelatinous glory. Ritual and taste aside, however, I count quality bone broth as an important supplemental food. The copious health benefits are simply too substantial to pass up.
Some of you, I know, are bone broth fans—a few even connoisseurs. You’ve been making your own for decades, maybe with recipes you learned in your grandparents’ kitchen. But what does the average Primal type need to know about bone broth? What goes into making it? What are the distinct health advantages? Are there risks or downsides? What are the alternatives? Finally, what about some recipes? I’m glad you asked….
What is Bone Broth?
Bone broth is simply a broth made by boiling bones (often with meat still on them). Usually vinegar is added as a medium (the thought is to draw out nutrients—more on this later). Sometimes vegetables, herbs, and spices are added for additional flavor and nutrients. Whereas soup is a meal, often containing vegetables, grains, seasonings, and even beans, bone broth stands on its own and is usually more cooked than soup.
Bone broth is an ingredient than can be used to create or flavor all kinds of dishes. It contains parts of the animal we typically like to discard (like cartilage and bone marrow), all nicely broken down so we get the full dose of nutrients.
What You Need to Know about Collagen
Inside the matrix of bones, there are many proteins including collagen, which forms the inside fibrous part of the bone.
Collagen is a group of amino acids making up 25-35% of our body. It’s found in our bones, skin, joints, tendons, and ligaments. As we age, we lose collagen. This contributes to age-related joint issues, not to mention the loss of skin elasticity.
Type I is found in bone, skin, ligaments, tendons and the white of the eye, and makes up 90% of the collagen in the body. Type II is found in the cartilage. Type III is found in bone marrow and lymph, also known as reticulin fiber.
Why Is Collagen So Important?
Glycine is the primary amino acid found in collagen. And it’s a pretty significant amino acid in terms of what it does for the body. Glycine is a non-essential amino acid, meaning our body can synthesize it. However, it’s actually considered “conditionally essential,” as it’s synthesized from the amino acid serine at only about 3 grams per day—not nearly enough for our requirements.
The human body requires at least 10 grams per day for basic metabolic processes, so we have a pretty significant daily deficit that we need to get through dietary or supplement means. Most of us these days aren’t eating ligaments and tendons and rougher cuts of meat containing glycine.
Bone broth contains approximately 27.2 grams of glycine per 100 grams of protein. Therefore, it makes for a great source of this amino acid. Rather than taking an isolated glycine supplement, bone broth contains glycine with other amino acids and minerals, which act synergistically with each other. Here are a few of the benefits glycine offers….
Contrary to what you might have heard, these non-essential proteins are pretty darn useful. A study was done on a hundred women between the ages of 40 and 70 who presented with knee joint pain or discomfort. (PDF) The results suggested that collagen increases the proteoglycan content in knee cartilage after 6 months of treatment. We need at least 10 grams of glycine each day for basic metabolic processes. One of those processes is the maintenance of the collagen in our body (the most abundant protein we carry, in fact).
Collagen concentrates where joints meet and in the connective tissue binding us together. Those 10 grams of glycine is just for maintenance, not repairing tissue after injury, or recovery from intense lifting. If you lift heavy, or are recovering from any sort of joint damage, supplementary collagen will improve your recovery.
It Can Help Keep Skin Supple
Research suggests collagen may act as a biological messenger, triggering the synthesis of new collagen fibers and extracellular matrix recognition by stimulating fibroblasts.
It Restores Glutathione
Glutathione protects against oxidative stress, and helps decrease the impact of bad estrogens that can build up over time, compromising our hormonal health.
It May Improve Cognition
N-methyl-D-aspartate (NMDA) receptors play a significant role in learning and memory. Targeting the glycine modulatory site of the NMDA receptor has been suggested as a therapeutic strategy to improve cognition. Glycine is considered an “inhibitory neurotransmitter,” and can act in the brain similarly to an antidepressant, without all the side effects.
It Can Improve Sleep Quality
It does this by decreasing core body temperature and increasing cutaneous blood flow. Cooler body temp means deeper sleep. One of my go-to “sleep hacks” is a big mug of bone broth about an hour before bed. It always knocks me out (in a good, non-narcotic way). And according to research, I’m not making this up or suffering from placebo. Human studies show that 3 grams of glycine taken before bed increases the quality of your sleep and reduces daytime sleepiness following sleep restriction. Sipping bone broth before bed provides a bioavailable source of glycine, helping us achieve deeper, more restorative sleep at night.
Other Key Nutrients in Bone Broth
Cartilage: the Home of Chondroitin and Glucosamine
When is the last time you felt the urge to chew on a juicy piece of cartilage? Probably not so much. We tend to discard those parts of the animal containing cartilage like the nose, ears, and joints. However, joint cartilage is easily broken down in well-cooked bone broth. Cartilage contains collagen protein and elastin. Elastin fibers play a big role in maintaining the integrity, elasticity, and the mechanical properties of cartilage.
Cartilage also contains glucosamine and chondroitin, both well known supplements for arthritic pain, particularly in the knees. In this study, glucosamine–chondroitin combined resulted in a statistically significant reduction in joint space narrowing at two years. Seeing as how those supplements get the chondroitin sulfate directly from animal cartilage, why not just eat the cartilage, or a bone broth made with plenty of cartilaginous substrate? Be sure to use bones with joints, like chicken feet and beef knuckles. Chicken backs are also a great source of chondroitin and glucosamine.
Bone Marrow: Deep in the Inner Matrix of the Bone
Bone marrow, found deep in the center of the bone, is also worth noting. There are two types: red bone marrow and yellow bone marrow. Yellow bone marrow is higher in fat cells, whereas red bone marrow is higher in platelets. Red bone marrow contains reticulin fibers, or type III collagen. Chicken bones have higher red marrow and make for a more flavorful broth. Bone marrow is fatty and gelatinous, and the marrow contains most of the minerals. Cooking bones longer (24-36 hours) will yield more of those minerals into the broth.
Bone Marrow Fat Is More Than Just Fat
A University of Michigan-led study shows that the fat tissue in bone marrow is a significant source of a hormone called adiponectin. These researchers discovered that the adiponectin in bone marrow helps with insulin sensitivity, and has been linked to decreased risk of cardiovascular disease, diabetes, and obesity-associated cancers.
Hyaluronic Acid: slippery synovial lubricant
Sure you can get powdered gelatins, but these do not contain many of the valuable nutrients that work synergistically with gelatin, such as hyaluronic acid. Found in many high end beauty serums, hyaluronic acid is the main component in synovial fluid, acting as a joint lubricant. You can also find hyaluronic acid in the bones and the connective tissue (usually attached to the bones). This study compared hyaluronic acid with NSAIDs for knee osteoarthritis. Both worked about the same, but hyaluronic acid is a safer alternative.
Proline: another noteworthy amino acid in bone broth
Let’s not ignore proline. Proline forms the structure of collagen, and like glycine, is a “conditionally essential” amino acid that we can get through our diet. To the point, it’s found in bone broth. Proline is needed to build collagen, to increase collagen synthesis in human fibroblast cells. As a result, it’s an important amino acid for skin health. Proline is great for healing, especially after intense workouts or straining the body. Animal studies suggest that proline helps with skin wound healing. People recovering from injuries have a higher need for proline. And don’t forget, heavy lifting is a stress to the body that requires recovery.
What about Minerals?
Bone broth can be high in minerals such as calcium and magnesium—with one caveat.
Recent research showed that bones cooked for more than eight hours were found not to exceed low tenths of a milligram per serving, or <5% of the daily recommended levels of calcium and magnesium. Another study highlighted veal bones sliced open to expose the marrow, placed in water with vinegar (more on vinegar later), and boiled for nine hours. The mineral loss from bones into the broth was extremely low—just a few milligrams of calcium and magnesium.
Keep in mind that longer cooking times (24-36 hours), where the meat falls of the bone and the bone really breaks down, tend to yield different results. It takes a long time for bones to break down and to get those interior nutrients. The marrow contains most of the minerals. Therefore, I probably wouldn’t rely on bone broth as a primary source of minerals if cooking under 24 hours, but with a longer cooking time I’d expect decent mineral content.
Are There Any Negatives to Bone Broth?
I’ve discussed many of the nutrients and positive benefits of bone broth, now let’s dive into some potential drawbacks. One concern often brought to my attention is the potential level of heavy metals found in bone broth. Some research says to avoid it because of markedly high lead concentrations, while other research suggests that the risks associated with the ingestion of heavy metals such as Pb and Cd in broth are minimal, since levels were extremely low.
I’m not too worried. That second study had several limitations, which the Weston A. Price Foundation has covered pretty well. The focus should be on sourcing of the bones. What matters is how much lead the animals you’re using to make broth are exposed to throughout their lives. I’d like to see a comparison between chicken broths made from animals from different farms and environments.
The animals’ environments and upbringing are everything. Weston Price describes a follow-up study into two broths made from grass-fed beef bones and pasture-raised chicken bones that was unable to detect any lead in either. This despite the chickens having plenty of access to dirt and all the same dirt-dusting proclivities their kind is known for.
Another concern I often hear about is the glutamate content. Bone broth that cooks for over 48 hours releases more glutamate, which raises concerns for people with neurological issues such as autism, ADHD, and multiple sclerosis. The theory is that excess free glutamate found in long cooked broths may cross the blood brain barrier (for those with “leaky brain”) and may be harmful for these particular folks.
Glutamate is an excitatory neurotransmitter and is naturally high in some nutritious foods such as bone broth, soups, and even sauerkraut. This doesn’t condemn the food and make it toxic. Most of us can process it just fine. Glutamate is only an issue if the person is highly sensitive to it. If you’re sensitive to glutamate or have a neurological condition of some kind, you may need to start with shorter cooking times, and gradually building up to see what you can handle. Keep in mind that there are many other foods we consume that are much higher in glutamate than bone broth. In my opinion the health benefits far outreach glutamate concerns for most people.
Beyond these suggestions, downsides you might hear include the taste and convenience. Oftentimes, when people tell me they just can’t stomach bone broth, I’m skeptical of what they’ve tried in the past. Recipe makes a big difference (as with any food). Let’s just say I’ve been able to change quite a few people’s minds with the good stuff. That said, others never quite get over the aversion. It’s just to their thing.
Likewise, it is a time commitment to make your own. It’s not hard. In fact, I dare say a basic bone broth is one of the simplest things you can cook. You just need time, which I know isn’t always practical. Carrying it around isn’t always easiest either. But the benefits of collagen are frankly too good for your health to pass up.
(Of course, that’s why I created Collagen Fuel and Collagen Bars—because I wanted an alternative for myself and others who desire a more convenient collagen source at times.)
But now let’s get down to the real business….
How to Make an Awesome Bone Broth
Add Vinegar to My Broth? Yes or No?
I used to religiously add a big glug or two of vinegar to every batch of broth, but not anymore. I’ve never actually noticed a difference. The reason being is that the broth would need to be much more acidic to draw out the minerals. A splash of vinegar doesn’t really work, and you don’t want your broth to be pure vinegar. Another option I’ve discussed before is to simmer the bones in red wine first, then add water, or to smash the bones in vinegar before cooking, increasing the surface area exposed to cooking. Both of those methods can draw out more minerals.
Which Bones Will Give Me the Richest, Most Gelatinous Broth?
For the most luxurious, gelatinous flavorful broth, be sure to favor bones with joints. You want those intersections and moving parts! This is where the cartilage, collagen, and synovial fluid are highest, translating into legit bone broth. Include parts like knuckles, feet, tails, necks, backs, wings, and ears! Don’t be afraid to even cook the head of the animal in your broth. Bone broth is a great way to be resourceful, and use the entire animal.
Broth Variations and Recipes
Over the years I’ve shared a variety of recipes and variations for making different broths. Here is a compilation of my bone broth variations: chicken bone broth four ways, and turkey stock. It’s fun to play around with different seasonings, different bones, with and without vegetables, roasting and not roasting the bones, etc.
For those of you who enjoy bone broth but would rather not always cook your own (I’m one), I asked Kettle & Fire (a company, in the interest of full disclosure, that I believe in and even invested in) to offer a deal to MDA readers who wanted to try their product. Depending on the package you order, you’ll get up to 3 FREE cartons when you order their chicken bone broth (excellent flavor in my book).
That’s it for me, folks. Let me open it up for discussion now. Questions, additional recipes, comments? What’s your unique reason (or favorite way) to enjoy bone broth? Thanks for stopping by, and take care.
Mark Sisson is the founder of Mark’s Daily Apple, godfather to the Primal food and lifestyle movement, and the New York Times bestselling author of The Keto Reset Diet. His latest book is Keto for Life, where he discusses how he combines the keto diet with a Primal lifestyle for optimal health and longevity. Mark is the author of numerous other books as well, including The Primal Blueprint, which was credited with turbocharging the growth of the primal/paleo movement back in 2009. After spending three decades researching and educating folks on why food is the key component to achieving and maintaining optimal wellness, Mark launched Primal Kitchen, a real-food company that creates Primal/paleo, keto, and Whole30-friendly kitchen staples.