Bone broth Miso soup at Ramen Isshin in Toronto, in 2015.Kevin Van Paassen/The Globe and Mail
Apple cider vinegar, it seems, is out. Ditto for coconut oil and lemon water. The latest trend-topping health and wellness cure-all is bone broth. That’s right, soup stock.
Bone broth became popular in recent years due to the Paleo diet, which focuses on meat, fish, vegetables and nut and seeds, foods our hunter-gatherer ancestors ate. Today, though, bone broth is so fashionable it’s a key ingredient in weight loss plans.
It’s also claimed this meaty elixir delivers a surplus of nutrients, along with a lengthy list of health benefits including smoothing wrinkles, easing joint pain, strengthening bones, boosting immunity, aiding detoxification and curing a “leaky” gut.
Is bone broth the real deal? Here’s what we know about bone broth – and what we don’t.
What is bone broth?
Home cooks and chefs have been making bone broth to flavour soups, stews and sauces for centuries.
Bone broth, a.k.a. stock, is made by simmering the bones and joints of animals in water with added vinegar (or wine) for 24 hours or longer; vegetables and herbs are sometimes added.
This process breaks down collagen in animal tissues forming gelatin, which gives bone broth its characteristic thickness. Collagen, the most abundant protein in the body, is the main component of connective tissue found in bone, cartilage, tendons, skin and other tissues.
Regular broth, on the other hand, is made by simmering water with meat, vegetables, herbs and spices for up to two hours. It may or not contain bones; if it does, it contains more meat than bones.
You can make bone broth from scratch or you can buy it powdered, instant or frozen at grocery stores, natural food stores and online.
Is it nutritious?
The nutrient content of bone broth varies depending on the amount and types of bones used (e.g., beef, chicken, fish) and for how long it simmers. The longer the cook time, the more collagen and nutrients seep out of the bones into the broth.
Thanks to its collagen content, bone broth can be a decent source of protein, supplying anywhere from 5 to 15 g per one-cup. (For perspective, two large eggs deliver 13 g of protein.) Regular broth typically contains one gram of protein per cup.
Animal bones are a good source of calcium, magnesium, phosphorus and potassium, as well as other trace minerals. The amount of minerals that actually ends up in homemade bone broth, however, is unknown.
Nutrition labels on commercial bone broth products indicate that they’re far from packed with minerals.
The products I looked at contained, per serving, at most, 10 mg of calcium (adults need 1,000 to 1,200 mg daily) and less than 0.5 mg of iron. Potassium content ranged from 10 to 350 mg per serving (adults should consume 4700 mg per day).
To boost the nutritional value of homemade bone broth, add vegetables like carrots, leafy greens and onions.
What about the health claims?
The touted benefits of bone broth stem from its individual ingredients, especially collagen, not from the broth itself.
While some trials have shown supplements of collagen peptides (short chains of collagen) to improve skin hydration and elasticity in women, bone broth has not been tested for skin aging.
The same goes for joint and bone health. The evidence for collagen supplements is weak, but the effect of bone broth on either is unknown.
Collagen in bone broth doesn’t head straight to your skin, bones or joints. Once digested, collagen, like all protein-rich foods, gets broken down into its individual building blocks, amino acids.
Experts contend that these amino acids will be used where they’re needed most at the time – to repair muscle tissue, synthesize hormones or enzymes, or assist the immune system, for example.
Aiding detox? Healing your gut? Sure, bone broth may contain certain nutrients and amino acids used for liver detoxification and the maintenance of healthy intestinal cells. But that doesn’t prove that drinking bone broth boosts these processes.
Weight loss? Add bone broth, at 30 to 60 calories per one-cup, to a low-carb diet that also includes intermittent fasting and, well yes, you’ll very likely shed pounds. But don’t credit bone broth for your results.
Bottom line
Bone broth’s health claims are largely untested and, therefore, unfounded.
That doesn’t mean, though, that bone broth shouldn’t be a part of your diet. It’s tasty, delivers satisfying protein and, depending on the ingredients used to make it, can offer a good source of certain vitamins and minerals.
But with any so-called superfood, don’t expect miracles.
Leslie Beck, a Toronto-based private practice dietitian, is director of food and nutrition at Medcan. Follow her on Twitter @LeslieBeckRD
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