Bone broth is made by simmering meaty bones for many hours, said Rachael Mamane, former owner of a small batch stock company called Brooklyn Bouillon and author of the cookbook Mastering Stocks and Broths. Often, cooks use bones from beef, pork or chicken, especially those with joints and with connective tissue still attached.
It’s similar to other types of broth or stock in terms of ingredients and taste, and any of them can be a base for soups or stews. But bone broth is typically distinguished by its use of those meaty joint bones, longer cooking time and the health benefits ascribed to it.
The hours of simmering help extract more protein from the bones and connective tissue than is typically found in other broths and stocks, Mamane said.
A carton of chicken bone broth made by the brand Pacific Foods, for example, contains 9g of protein per serving, whereas its chicken stock has 6g and its chicken broth has 1g.
Most of the protein in bone broth comes from collagen, which makes animals’ tissues stronger and more flexible, said Keith Baar, a professor of molecular exercise physiology at the University of California, Davis. As the broth simmers, the collagen dissolves from the bones and tissue, Baar said.
The proteins from the collagen then form gelatin when chilled, giving the broth its characteristic texture.
“If it jiggles, that’s good,” Mamane said.
Bone broth’s 'jiggly' texture comes from gelatin, which forms when collagen is broken down. Photo / 123rf
Can it strengthen and repair joints?
One common claim is that the amino acids, or protein building blocks, in bone broth can help our tendons, ligaments and cartilage manufacture their own collagen, benefiting joint health.
In theory, this makes sense, Baar said. And some small studies have suggested that collagen and gelatin supplements may potentially strengthen muscles and tendons, help athletes recover and reduce pain in people with knee osteoarthritis, said Baar, who has received research funding from companies that make collagen supplements.
But this hasn’t been tested with bone broth. And some evidence suggests that the amounts of amino acids in home-cooked and store-bought bone broths can vary widely and be far lower than what is found in collagen supplements.
So even if collagen supplements do end up being good for your joints – and the jury is still out there – we can’t assume that bone broth will be, too, said Louise Burke, a professor of sports nutrition at Australian Catholic University in Melbourne, who has researched the topic.
Can it reduce gut inflammation and ‘leakiness’?
Bone broth is relatively high in the amino acid glutamine, and some animal and small-scale human studies have suggested that glutamine supplements may reduce gut inflammation and the “leakiness” of the gut lining, said Dr Michael Camilleri, a gastroenterologist at Mayo Clinic in Rochester, Minnesota.
In one study published in 2021, researchers reported that when a small number of mice drank bone broth for 10 days, they were less susceptible to intestinal damage and inflammation than those that drank water. But whether bone broth could have a similar effect in people hasn’t been examined.
Camilleri said it’s plausible that sipping bone broth could be good for your gut, but we can’t yet say that it’s “a miraculous cure” for gastrointestinal symptoms.
Can it plump and tighten your skin?
The collagen in your skin is partly responsible for its firmness and elasticity, said Dr Rajani Katta, a dermatologist at Baylor College of Medicine in Houston. And some studies suggest that taking collagen supplements may benefit skin health, though many were funded by supplement manufacturers. Katta considers the evidence for collagen supplements to be preliminary and unconvincing, and she wasn’t aware of any studies of bone broth’s effect on our skin.
Homemade bone broth may contain far less collagen than supplements. Photo / 123rf
Should I sip the broth or not?
As with many store-bought stocks and soups, bone broths can be high in sodium, said Amy Bragagnini, a dietitian in Grand Rapids, Michigan. So read nutrition labels carefully or consider making your own with less salt.
And because bones can leach lead during cooking, Baar said, you might want to limit yourself to one or two servings of bone broth per week – especially if you’re pregnant – and use the same caution if you’re feeding it to a young child.
That said, bone broth is a good source of protein, Bragagnini added, and it’s “light and easy on the stomach”, so it can help you stay nourished and hydrated when you’re sick or don’t have an appetite.
Just know that it may not be the cure-all that some influencers claim.
