Nana's favourite broth recipe is having a moment, but what are the benefits?

Celebrities like Gwyneth Paltrow, Kylie Jenner and Salma Hayek swear by it. DR CATHERINE CONLON looks at whether bone broth is worth the hype.

Rich in nutrients – it may support the health of your bones and digestive system.

There’s nothing in the world quite like a steaming bowl of homemade chicken broth.

Golden, piping hot, deliciously savoury and full of nourishment, this old-fashioned recipe of our grandmothers, made from extracting broth from bones and scraps of vegetables, is having a moment.

Celebrities like Gwyneth Paltrow, Kylie Jenner, and Salma Hayek swear by it, touting its ability to improve gut health, keep skin and hair glowing, maintain bone strength, ensure better sleep, and improve digestion. Sports figures like Kobe Bryant claim bone broth helps recovery.

With the hashtag #bonebroth stacking up over 200 million views on TikTok - featuring everything from recipes to ‘I tried drinking bone broth for a month and this is what happened’ stories - bone broth looks like it is here to stay for the near future.

But is there any evidence to back up these claims? While the scientific research on bone broth is still limited, some experts suggest that the benefits of bone broth may be to do with the overall nutritional content, including collagen and amino acid content, that has allowed it develop its reputation as a magical healing remedy.

What is bone broth?

Bone broth is exactly what it sounds like – a broth or stock made by simmering the bones and connective tissue of animals that forms a stock for soups, gravies or stews. It can also be used as a nutritious drink.

While our grandmothers famously swore by bone broth, in fact it dates back much further to prehistoric times when hunter-gatherers boiled otherwise inedible animal parts, including bones, hooves and knuckles into a broth they could drink.

It can be made from any animal – including chicken, beef, veal, turkey or fish. Inedible connective tissue parts like gizzards, hooves, fins and beaks can also be used.

Making broth is very simple using a combination of water, apple cider vinegar, animal bones, and salt and pepper to taste. The ingredients are placed in a large pot, brought to a boil, and allowed to simmer for hours, 12 to 24 hours even. The longer it cooks, the better the taste and the more nutritious.

Once cooled and strained, it is ready for use. It can be combined with a variety of herbs and vegetables for added flavour or used as a base for gravies, stews, or even served over pasta or meatloaf.

Health benefits

Depending on the variety of bones used, the broth can be a rich source of vitamins and minerals. including calcium and magnesium that are essential to maintain bone strength.

Animal bones and marrow also contain the protein collagen, which forms gelatin when cooked.

There is some evidence linking gelatin to various health benefits, including skin, bone, gut, and joint health, but more research is needed.

Digestion

Animal research published in Food Science And Nutrition in 2018 suggested that gelatin may help to heal the mucosal lining of the gut in animals with inflammatory bowel disease – more research is needed to confirm this.

Further research reported that gelatin may be important in preventing ‘leaky gut’, where the barrier between the gut and the bloodstream is damaged, allowing substances to leak from the gut into the bloodstream, leading to inflammation and illness.

Research on mice linked the amino acids in bone broth to reduced inflammation in the gut due to ulcerative colitis.

The evidence available, which is not exactly prolific, suggests bone broth may be beneficial for people with a range of digestive disorders but further research is needed.

Sleep

Amino acids are the building blocks of protein. The amino acid glycine, present in bone broth, has multiple functions in the body, including supporting healthy sleeping patterns.

Research published in Sleep And Biological Rhythms in 2016 found that taking a glycine supplement before bed improved the quality of sleep in individuals who had difficulty sleeping. It was also linked to falling asleep faster, maintaining a deeper sleep, and waking up less frequently.

The researchers also reported that glycine helped reduce daytime sleepiness and improved memory and mental function.

Drinking bone broth could therefore have similar benefits. However, the amount of glycine in bone broth is 500-1,700 mg. So, you may have to drink two to six cups of it to achieve the same levels of glycine as were used in the sleep study.

Powerful combination

If you are planning to make bone broth from scratch, it is a good idea to collect leftover bones and carcasses from meals and store them in a freezer until you are ready to cook them. It is best to make it in a large batch, but it only stores in the fridge for 3-4 days.

If you need to save it for longer than this, you can freeze it in small containers and defrost individual servings as you need them.

Bone broth is widely touted as being a powerful remedy to promote bone and gut health, healthy skin, and glowing hair.

The research to substantiate this is more limited. What we do know is that it does contain a powerful combination of vitamins, minerals, and protein that has the potential to support these claims.

If you are choosing between bone broth or an ultra-processed alternative out of a jar as the base for a soup or casserole or stew, there is no doubt which is likely to be the health champion.

Dr Catherine Conlon is a public health doctor in Cork and former director of human health and nutrition at Safefood.