Summary

Is bone broth harmful? For most people, no. Traditional simmered broths like chicken soup have long been valued as nourishing and easy to digest. Yet some people worry about heavy metals, histamine or glutamate sensitivity. Here’s what the evidence actually shows.

Key Takeaways

• Broth is a food, not a measured dose. The glutamine trials used above 30 grams a day, far more than a mug provides.
• The heavy metal worry traces back to one small 2013 study. Later research measured lead and cadmium at a few micrograms a serving and judged the risk minimal.
• Broth is a poor source of calcium. A serving gives less than 5 per cent of the daily requirement.
• Histamine builds up as broth stands. Cool and freeze it quickly. Around 1 to 3 per cent of people are sensitive to it.
• Meat stock suits the early GAPS phase better, because its glutamate content is much lower.

Introduction

Bone broth has been made in kitchens for centuries. A pot of bones, water and time, left to simmer while you got on with something else.

Every food culture has a version. Chicken soup when someone is poorly, pho in Vietnam, Scotch broth here at home. People made it because it used the whole animal, and because it was nourishing.

Now it is sold as a health food, and the claims have grown with it. Some say it heals the gut lining. Others warn that it is full of lead.

Neither is quite right. Here is what broth gives you, where the worries came from, and who should be careful.

The Benefits of Bone Broth

Animal bones contain proteins, minerals such as calcium and magnesium, and other nutrients. If we simmer these bones, it’s not unreasonable to expect that this valuable nutritional content would transfer into the cooking liquid. A slow cooker or stock pot can be very useful, especially if making a big batch of homemade bone broth. The long and slow cooking when making broth, breaks down the bones (usually chicken, lamb, beef or fish) and cartilaginous material.

The recommendations for broth-making often suggest starting from cold water, adding meaty bones, and raising the temperature to a simmer. Continue to simmer in hot water for several hours, or even up to a day or more. Some people also like to add vegetables, herbs, seasonings or vinegar, making a bone broth soup. Longer simmering of meaty bones in water helps to break down connective tissue and release the nutrients. I like to make chicken bone broth. It is relatively quick to make and tastes good. Chicken bones simmered for twenty-four hours will crumble between your finger and thumb, showing how much of their structure has passed into the liquid.

If you are looking for a natural source of minerals such as calcium, broth might seem a good option. In fact, the measured amounts are surprisingly small. However, broth is a useful source of amino acids such as glutamine.

Supplements of glutamine are sometimes recommended to support the health of the intestinal barrier. So, if you are trying to heal a leaky intestinal lining, then you may have heard about the nutritional benefits of broth. A 2025 review brought together the research on broth and the gut barrier. Glutamine is the main fuel for the cells lining your intestine, and glycine and proline help to support the proteins that hold the lining together. Most of that evidence comes from laboratory and animal studies at this stage. In people, a pooled analysis of ten trials found glutamine supplements reduced gut permeability only at doses above 30 grams a day, which is far more than a mug of broth provides. Broth is a food rather than a supplement, and its place is in the daily diet rather than as a therapy on its own.

You might also like my post: Heal Your Gut Lining Naturally

The Best Bones for Bone Broth

The types of bones you use will affect the nutrient content of your broth. It takes far longer to extract nutrients from bigger bones such as beef bones than it does from poultry bones. Also, the long bones, such as thigh bones have a different composition than the flat bones such as ribs or shoulder blades. The long bones are composed of what is called compact bone and have a higher content of minerals than flat bones.

As well as minerals, bones are a good source of several amino acids and broth mainly contains the non-essential amino acids, proline, glycine, glutamine and alanine. Non-essential means they are not an essential part of the diet as the body can make them. These amino acids can help to strengthen or build the proteins in your body.

They are also the same amino acids your body uses to make collagen, the protein that supports your skin, hair and nails. A meta-analysis of 26 trials, covering more than 1,700 people, found that collagen supplements improved skin hydration and elasticity. Broth is not a measured dose, though. Researchers who analysed a range of broths found the amino acids that build collagen varied widely from batch to batch, and were mostly lower than the amounts used in those trials. So a daily mug of broth gives you a gentle supply of the raw materials rather than a trial dose. The protein it provides also plays its part in maintaining your muscle.

In addition, it is beneficial to make your broth from bones that contain joints. The cartilage, tendons and other connective tissue in joints provide a rich source of nutrients such as glucosamine, chondroitin sulfate and hyaluronan. These nutrients may help to build and repair the joints in your body, improving your joint health.

You might also like my post: Natural Joint Pain Relief

Are There Any Health Risks with Bone Broth?

Some people suggest that drinking broth on a regular basis may present a potential health risk.

Some potential reasons there may be problems with consuming bone broth:

• lead and other heavy metals in animal bone
• some people may be sensitive to glutamate levels in broth
• some people may be sensitive to histamine in bone broth
• bone broth may contain food allergens such as shellfish
• bacterial contamination in bone broth, from improperly prepared or stored bone broth
• bone broth may contain amino acids or minerals that interact with some medications such as blood thinners

Bone Broth and Toxic Metals

As well as the beneficial minerals such as calcium, magnesium and zinc, it’s possible that bone contains heavy metals. For instance, the bones may contain toxic metals such as cadmium or lead. And, just as we extract the calcium or magnesium we could also extract toxic heavy metals. The worry began with a small 2013 study that reported lead in broth made from chicken bones and skin, and it is still the study behind most of the warnings you will read online.

However, this study found that not only was the concentration of calcium and magnesium low in broth. But, heavy metals were either not found, or the concentration was so small as not to be a concern. Researchers found that both homemade broth and commercial brands contained low amounts of calcium and other minerals. In fact, for each serving of broth, they estimated that calcium levels were less than 5% of the daily requirement. Though they did find that adding an acidic ingredient such as vinegar could increase the calcium levels of a batch of bone broth. This suggests that adding vinegar during cooking might also increase other metals in broth too. Even so, the researchers measured the lead and cadmium in a serving at a few micrograms, and concluded that the risk from drinking broth is minimal.

Glutamates, Broth and the GAPS diet

Gut and Psychology Syndrome (GAPS) diet is a special diet for children with autism. It starts with an introduction phase. In this initial part of the GAPS diet, it is better to have meat stock rather than broth made from bones. Meat stock contains the same healing amino acids as broth from bones. But, the concentration of glutamate in meat stock is much lower.

Meat stock preparation involves simmering meaty bones. But cooking times are shorter. For instance, cooking time for meat stock is less than two hours. While for bone broth stock the cooking time is usually between 1 to 3 days.

On the GAPS diet, there is a slow transition from using meat stock to using broth made with bones. As the gut heals, people can better tolerate broth.

The manufactured additive monosodium glutamate (MSG) is a concentrated source of free glutamate, and some people report headaches after eating it. When researchers reviewed the trials, a consistent link with headaches was harder to show than the reputation suggests, particularly once MSG was eaten with food. Glutamine in broth can convert into glutamate. And some people think there may be a link between glutamate and migraine headaches, ADHD or autism, which is part of the thinking behind the GAPS approach.

Unfortunately, MSG or similar food additives, such as yeast extract, are found in most processed or packaged foods. These man-made additives are concentrated sources of glutamates. And they can cause side effects in some people. For this reason, I would recommend that everyone should avoid processed foods wherever possible. This is especially true if you suffer from migraine headaches, neurological or digestive problems.

Similarly, bone broth may also cause problems for some people. One theory is that this occurs when the brain has an excess of free glutamates from eating a poor diet. Adding even a small amount of glutamate adds to the excess of glutamate in the brain creating overstimulation. If you find consuming broth causes headaches or other reactions then it makes sense to limit how much you eat.

Bone Broth and Histamine Intolerance

Another possible issue with broth is histamine intolerance. Bones and meat contain the amino acid histidine, and bacteria carry an enzyme that converts histidine into histamine. The longer meat and bones are stored, and the longer a finished broth stands, the more opportunity there is for histamine to form. So, bone broth can contain histamine, and the histidine can continue to form histamine with storage. When your batch of broth is finished and cooled, freeze it quickly to minimise the production of histamine.

If you are freezing broth in glass jars, make sure you only use freezer-safe jars and don’t overfill them.

For most people, histamine in foods does not cause a problem. But it is true that some people are very sensitive to the amount of histamine they consume. Researchers estimate that between 1 and 3 per cent of people have this kind of sensitivity, usually because the enzyme that clears histamine from the gut is in short supply. If you develop an itchy skin rash, hives, stomach upset, migraine headache or a runny nose it could be due to histamine.

You might also like my post: Herbal Remedies for Histamine Intolerance

Osteoporosis and Bone Broth

In osteoporosis, bone loss is faster than the rate of bone creation and bones become weaker and brittle and much more susceptible to fractures. Osteoporosis has been called a silent disease meaning that it can progress without someone being aware of it happening. While bone density naturally decreases with age, women are more at risk after menopause.

A 2024 study fed chicken and vegetable bone broth to rats whose ovaries had been removed, mimicking the hormonal state after menopause. The rats given broth kept more of their bone density than those without it, and the researchers traced the effect to two of its components, hyaluronan and chondroitin sulfate. There is no human data yet, so this is early research rather than a proven benefit.

You might like my post: Sesame for Hormones, Bones and Heart Health

Lifestyle changes such as weight bearing exercises and limiting alcohol consumption can help to avoid bone loss. Other natural approaches include eating mineral-rich foods such as leafy greens, nuts and seeds and bone broth may also help to protect bone health.

You might also like my post: Can dietary change reduce bone loss in osteoporosis?

Is Bone Broth Safe for You?

While it is possible that bone broth may cause problems for some people, this is not true for everyone. In fact, it is likely that most people will thrive on it. For instance, it seems that the potential risks of heavy metal content is unlikely to be an issue. On the other hand, if you develop signs of histamine sensitivity, allergic reactions, or have a known glutamate sensitivity, then you may need to limit or avoid regular consumption. If you experience any side effects whilst consuming bone broth then it is a good idea to speak to a healthcare professional for further investigation.

You might also like my post: Is Chronic Inflammation Secretly Weakening Your Bones?