Bone Broth
Collagen
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Time to read 24 min
"A good broth can resurrect the dead."
Bone broth is one of the oldest and most practical foods in human history. Long before it became a wellness trend, people simmered bones, joints and connective tissue to extract flavour, nourishment and every last useful part of the animal.
Today, bone broth is used in many of the same ways: sipped as a warming drink, stirred into soups and stews, used as a base for sauces, or taken as a convenient source of protein, collagen-derived gelatin and amino acids.
But what does bone broth actually contain? How is it different from stock? And what does the evidence say about its benefits for digestion, sleep, joints, skin, metabolic health and everyday nourishment?
This guide explores the history, nutrition and science of bone broth, as well as a simple guide to making your own chicken or beef bone broth at home.
Table of Content
Bone broth is a slow-cooked broth made by simmering animal bones, joints, cartilage and connective tissue in water for a long period of time. The long cooking process helps release gelatin, amino acids and other compounds from the bones and connective tissue.
The result is a savoury, nutrient-rich liquid that can be drunk on its own or used in cooking.
Bone broth is not a modern invention. Archaeological evidence suggests humans were boiling bones from at least the Middle Pleistocene period, around 420,000 years ago.[1] The oldest known written recipes, recorded on Babylonian clay tablets dated around 1730-1600 BCE, describe broths made with meat, herbs and aromatics.[2]
Bone broths also appear in traditional food and medicine systems across the world. In 2010, archaeologists in China uncovered a sealed bronze pot containing what was described as 2,400-year-old bone broth.[3] Traditional Chinese Medicine has long used bone broths to support digestion and nourishment, while Hippocratic medical writing placed strong emphasis on broths and simple foods for those with digestive complaints.[4][5]
In other words, bone broth is not a fad. It is a practical ancestral food that grew from the need to waste nothing and extract as much nutrition as possible.
Bone broth and stock are often used interchangeably, but the main difference is cooking time and ingredient focus.
Stock is usually cooked for a few hours. It may include bones, meat, vegetables, herbs, spices and kitchen leftovers. A good stock brings flavour and some gelatin, especially if made with smaller bones, joints, feet or carcasses.
Bone broth is usually simmered for much longer, often 12-48 hours, or cooked under pressure to speed up the process. The main ingredient should be bones, whether large marrow bones, meaty bones, joint bones or smaller chicken bones.
That longer cooking time helps extract more gelatin from collagen-rich tissues. It also creates a richer, deeper flavour and a broth that may set into a wobble when cooled.
A simple way to remember it:
Stock is quicker and mainly culinary.
Bone broth is slower, bone-led and more nutrient-focused.
Bone broth is best understood as a nourishing drink, not a complete food. It does not compete nutritionally with organs such as liver or a varied whole-food meal, but it does provide a useful combination of amino acids that many modern diets lack.
A properly prepared bone broth usually contains around 8-10g of protein per cup, compared with roughly 2-6g per cup in many stocks.[6]
Most of that protein comes from collagen that has broken down into gelatin during cooking. This gives bone broth its distinctive texture and amino acid profile.
Hunter and Gather Grass Fed Cattle Bone Broth contains 15g of protein per serving, while Free Range Chicken Bone Broth contains 11g of protein per serving.
Collagen is the main structural protein found in skin, bones, cartilage, tendons and connective tissue. When bones and connective tissue are cooked for long enough, collagen breaks down into gelatin.
Gelatin is rich in amino acids, especially glycine, proline and hydroxyproline. Bone broth also contains useful amounts of glutamic acid, alanine and arginine.
Approximate amino acids per serving:
Amino acid |
Grass Fed Cattle Bone Broth |
Free Range Chicken Bone Broth |
Glycine |
3.4g |
2.1g |
Proline |
1.7g |
1.0g |
Hydroxyproline |
1.6g |
0.8g |
Glutamic acid |
1.7g |
1.3g |
Alanine |
1.4g |
0.8g |
Arginine |
1.3g |
0.6g |
Glycine is particularly important. Collagen is around one-third glycine, and a serving of bone broth can provide over 2-3g of glycine, depending on the product or recipe.[7]
Bone broth is often described as mineral-rich, but the evidence is more modest.
It can contain small amounts of calcium, magnesium, potassium and phosphorus, but it is not a major source of minerals compared with foods such as dairy, seafood or organ meats.[8]
Research shows that using acid and longer cooking times can increase mineral extraction, but even the richest broths tend to provide only small percentages of daily mineral needs.[9]
The encouraging finding is that toxic metals such as lead and cadmium appear to remain very low in properly prepared bone broths, well below safety thresholds.[9]
If you make bone broth at home, using large marrow bones can increase the fat-soluble nutrient content. Bone marrow is mostly fat, much of it monounsaturated fat, particularly oleic acid. It may also provide smaller amounts of omega-3 fats, especially when sourced from grass fed animals.
Testing reported by the Weston A. Price Foundation found bone marrow contains vitamins A, D, E and K2, with vitamin D levels higher than a glass of fortified milk in the sample tested.[10]
Further Readings
→ Bovine Collagen vs Marine Collagen: Which Is Better For You?
Research directly on bone broth as a whole food remains limited. Much of what we know is extrapolated from its main components, especially gelatin, collagen-derived amino acids and newer research into bone broth nanoparticles.
That said, the evidence around these components is substantial enough to explain why bone broth has been valued for so long.
One of the most interesting areas of newer bone broth research is the discovery of nanoparticles formed during long simmering. These are hybrid structures made from lipids and collagen fragments. Because of their size and stability, they may survive digestion and reach the colon intact.[11]
Animal research suggests these nanoparticles can influence immune cells, gut bacteria and intestinal barrier function. In one study, nanoparticles isolated from porcine bone soup helped regulate gut microbiota and improved IBD-related markers in mice with chemically induced colitis.[12]
Bone broth also contains amino acids with established roles in gut biology. Glutamic acid can be converted into glutamine, a preferred fuel for enterocytes, the cells that line the small intestine.[13] A healthy intestinal barrier is central to nutrient absorption, immune tolerance and keeping the gut lining functioning properly.[14]
Glycine, proline and hydroxyproline are also relevant because they are associated with mucus production, mucosal repair and tight junction integrity.[15][16] The mucosal layer is one of the gut’s first lines of defence against pathogens, toxins and inflammatory triggers.[17]
Animal studies have explored bone broth in models of inflammatory bowel disease. In a murine model of ulcerative colitis, bone broth was associated with protection of the gut lining, reduced inflammatory markers and improved bacterial balance.[18]
Glycine, the main amino acid in bone broth, has also been studied for its broader anti-inflammatory properties.[19]
This is relevant because ulcerative colitis can involve symptoms beyond the gut, including fatigue, anaemia, joint pain, skin problems and eye symptoms.[20] The gut is not isolated from the rest of the body, which is one reason gut barrier research has become such an important field.
Hydroxyproline, another collagen-derived amino acid, has also been studied in relation to oxidative stress in colonic cells.[21] Oxidative stress is one of the processes involved in inflammatory bowel disease, alongside immune activation and microbial changes.[22]
Arginine may also be relevant. Research shows arginine availability and metabolism are altered in ulcerative colitis, and animal studies suggest it may help buffer some forms of oxidative damage.[23]
Bone broth is naturally rich in glycine, and glycine is one of the better-studied amino acids for sleep.
Several small randomised controlled trials have found that taking around 3g of glycine before bedtime can improve subjective sleep quality, reduce next-day fatigue and support cognitive performance after restricted sleep.[24]
Mechanistically, glycine appears to act on receptors in the suprachiasmatic nucleus, the brain’s master body clock. This helps increase blood flow to the hands and feet, promoting heat loss and a natural drop in core body temperature, which is one of the body’s signals for sleep.[25]
A mug of bone broth in the evening may therefore be more than comfort. It provides a meaningful dose of glycine in a warm, savoury drink.
Most joint research focuses on collagen and gelatin rather than bone broth directly. However, because bone broth provides collagen-derived gelatin and amino acids, the research is relevant.
A 2024 meta-analysis of 35 randomised controlled trials involving 3,165 patients found collagen derivatives reduced pain and improved function in hip and knee osteoarthritis, with no increase in adverse events.[26] Earlier meta-analyses have also reported significant improvements in osteoarthritis symptoms with collagen supplementation.[27]
Glycine may also be part of the picture. In a laboratory study using living human cartilage cells, high glycine concentrations increased collagen synthesis by 60-75%. The authors suggested that glycine deficiency may be one factor involved in osteoarthritis and cartilage repair.[28]
In bone health research, a 12-month randomised controlled trial found that 5g daily collagen supplementation increased bone mineral density at the lumbar spine and femoral neck in postmenopausal women with osteopenia or early osteoporosis.[29]
Again, most evidence here relates to collagen peptides rather than bone broth as a whole. Still, the evidence helps explain why collagen-rich foods are often associated with skin, hair and nail conditions.
A 2023 meta-analysis of 26 randomised controlled trials involving 1,721 participants found oral collagen improved skin hydration and elasticity.[30]
In the same year, a double-blind clinical trial of 100 middle-aged women found that 1.65g of collagen peptides daily for 12 weeks improved skin moisture and elasticity while reducing flaking and wrinkles from around week four.[31]
Nail research is smaller but interesting. In a study of 25 women, 2.5g of bovine collagen daily for 24 weeks improved nail growth by 12%, reduced broken nails by 42% and improved brittleness by 64% according to physician assessment.[32]
A 2024 laboratory study on human scalp hair follicles found that collagen peptides helped maintain hair in its active growth phase and supported stem cells involved in new hair production.[33] A separate cell and rodent study found collagen peptides promoted hair growth and activated genes linked to hair follicle development.[34]
Some research suggests collagen and specific amino acids may play a modest role in metabolic health.
Randomised trials in people with type 2 diabetes, overweight or obesity have found collagen supplementation may improve fasting blood glucose, HbA1c, insulin sensitivity and fat loss. Proposed mechanisms include improved satiety, higher GLP-1 levels and activation of metabolic pathways such as PPAR-alpha and AMPK.[35]
This matters because insulin resistance and prolonged high blood glucose are linked with oxidation, inflammation and blood vessel damage.[36]
Alanine, one of the amino acids found in bone broth, has also been studied. A 2021 systematic review and meta-analysis found beta-alanine supplementation improved markers of glycaemic control and insulin resistance in humans and animals.[37]
The gut microbiome appears to shift during perimenopause and menopause, influenced by changes in oestrogen and progesterone.[38][39]
These hormonal shifts can overlap with digestive and psychological symptoms, and delayed recognition of perimenopause remains common.[40]
Bone broth is relevant here because it provides gelatin-derived amino acids associated with gut barrier function and contains the nanoparticle structures discussed earlier. Digestive symptoms are common in menopausal women, with bloating, constipation, stomach pain, reflux and IBS-like symptoms frequently reported.[41]
Bone broth is not a cure or a standalone solution, but it may be a useful, gentle food within a broader menopause nutrition and lifestyle approach.
Glycine is one of the most important amino acids in bone broth. Beyond sleep and gut barrier research, it has been studied for oxidative stress, mitochondrial function, metabolic syndrome and cardiovascular health.[42]
A 2024 narrative review also explored glycine’s possible protective role in cardiovascular health, including heart attacks, artery tears and blood vessel conditions.[43]
Emerging research suggests glycine supplementation may also influence psychiatric symptoms and physical performance, although more work is needed before strong conclusions can be made.[44]
Alanine has also been studied for high-intensity exercise performance. Beta-alanine increases carnosine levels in muscle cells, helping buffer acidity during intense exercise.[45][46] Other research has explored beta-alanine in relation to resilience, cognitive function, traumatic brain injury and heat stress in soldiers.[47]
Bone broth is generally well tolerated, but there are a few considerations.
Because bones can accumulate heavy metals over time, people sometimes worry about lead, cadmium, aluminium and arsenic in bone broth.
The evidence is reassuring. A 2017 controlled laboratory analysis of experimental and commercial bone broths found levels of lead, cadmium and aluminium were extremely low and contributed only a tiny fraction of tolerable daily intakes, even with regular consumption.[49]
A 2024 study also found low toxic metal levels in bone broths.[50]
For context, some dark chocolate products can contain far higher levels of lead and cadmium.[51] Spinach may contain much higher cadmium levels than bone broth samples, and brown rice can contain substantially higher arsenic and cadmium levels.[52][53]
Histamine is a signalling molecule involved in immune reactions, stomach acid regulation and wakefulness. Some people struggle to break down histamine efficiently, often due to issues with the enzyme diamine oxidase, or DAO.
Histamine can develop in animal foods during cooking, ageing, smoking, drying and storage. Because bone broth is cooked for a long time, it may not suit everyone with histamine intolerance.
If you suspect histamine intolerance, start cautiously. Some people may tolerate a small amount, such as a quarter serving, especially within a wider low-histamine diet, while others may need to avoid it.
Bone broth is difficult to study because recipes vary so much. Different bones, animal species, cooking times, acidity levels and preparation methods all change the final nutrient profile.
A 2025 review published in Digestive Diseases and Sciences noted that there is insufficient human research exploring the benefits of bone broth as a whole food.[54]
Only a small number of clinical trials have used bone broth directly. One dates back to 1934 and examined bone and vegetable broth, while a 2025 open-label clinical trial used bone broth as part of a very low-calorie diet for adults with obesity.[55]
There are also studies on chicken soup, including research from 1978 on nasal mucus velocity and airflow resistance, and a 2000 in vitro study showing that chicken soup influenced neutrophil chemotaxis, a process involved in the immune response.[56][57]
Overall, most bone broth benefits are currently inferred from research on gelatin, collagen, glycine, alanine and other amino acids rather than direct human trials on bone broth itself.[58]
That does not make bone broth unhelpful. It simply means we should see it as a traditional, nutrient-rich food with promising mechanisms, not a miracle cure.
Bone broth has earned its place as one of the most enduring traditional foods. It is simple, versatile and rooted in the practical wisdom of using the whole animal.
Modern analysis shows it is not the mineral powerhouse some people claim. Its real value lies in its collagen-derived gelatin, distinctive amino acid profile and emerging research into bone broth nanoparticles.
The strongest evidence does not yet come from bone broth trials directly, but from studies on its key components. Collagen, gelatin, glycine, proline, hydroxyproline and alanine all have research behind them in areas such as gut barrier function, sleep, joints, skin, nails and metabolic health.
Bone broth is not a substitute for a varied, nutrient-dense diet. It is not a cure-all. But as a warming drink, a savoury protein source, a base for soups and stews, or a simple ritual before bed, it remains one of the most sensible things you can do with bones.
Science is still catching up with what cooks and healers have known for centuries: bone broth comforts, nourishes and makes good use of what would otherwise be wasted.
Hunter & Gather
Hunter & Gather are an ancestrally-inspired lifestyle brand that fuses ancestral wisdom and modern innovation to guide your journey to better health. Our mission is to give you the tools to thrive for life. We create real food and supplements that are free from refined sugar, grains and inflammatory seed oils, while championing premium quality and taste.
Bone broth can be a useful addition to a nutrient-dense diet. It provides protein, collagen-derived gelatin and amino acids such as glycine, proline and hydroxyproline. It is not a complete food or a cure-all, but it is a practical way to add specific nutrients that are often lower in modern diets.
The main nutritional benefit of bone broth is its collagen-derived gelatin and amino acid profile. These amino acids, particularly glycine, proline and hydroxyproline, are linked with research areas including gut barrier function, sleep, joints, skin and metabolic health.
A properly made bone broth can provide around 8-10g of protein per cup, although this varies by recipe and preparation method. Some ready-made bone broths provide more, depending on how they are formulated.
No. Stock is usually cooked for a few hours and is mainly used for flavour. Bone broth is usually cooked for much longer, often 12-48 hours, with bones as the main ingredient. This longer cooking time helps release more gelatin from collagen-rich tissues.
Bone broth can be enjoyed at any time. Some people like it in the morning as a savoury alternative to tea or coffee, as a base for lunch or dinner, or in the evening because of its warmth and glycine content.
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