Everybody's raving about "bone broth" as the new miracle health elixir. What's actually in bone broth and what can it do for you? Nutrition Diva investigates the science behind the fad. Visit the website: http://bit.ly/14qraXa
Everybody's raving about "bone broth" as the new miracle health elixir. What's actually in bone broth and what can it do for you? Nutrition Diva investigates the science behind the fad. Visit the website: http://bit.ly/14qraXa
Move over, green smoothie. Bone broth is the hot new trend in health drinks, thanks to a recent spate of breathless articles in popular health and fitness blogs and magazines. There's even a trendy new restaurant in Manhattan's East Village, specializing in bone broths.
To be fair, Paleo dieters and Weston Price devotees have been extolling the virtues of bone broth for quite a while, but now everyone seems to be jumping on the bandwagon.
And why wouldn't you? Drinking bone broth is reputed to enhance energy, make your skin more youthful, heal a leaky gut, strengthen your bones and joints, enhance your sleep, and boost your immune system.
So, what's in this miracle health elixir to explain all these amazing benefits?
In reality, it's mostly water, plus some protein, fat, a few minerals, and a couple of non-essential amino acids. In fact, bone broth is nothing more or less than what cooks refer to as "stock," a broth made by boiling animal bones (and other parts) in water. If you made soup out of the bones of your Thanksgiving turkey this year, you ate bone broth! Now don't you feel trendy?>
When you boil bones in water, the nutrients in the bones and their marrow become dispersed in the water. Bones often have bits of meat, skin, and connective tissue attached to them, and the fat, proteins, and minerals in these tissues also dissolve into the water. Most of the benefits ascribed to bone broth are based on the purported effects of these nutrients.
Many claim, for example, that bone broth strengthens your bones because it is so rich in minerals. But according to the National Nutrient Database, the amounts of calcium, magnesium, and phosphorus in bone broth are pretty modest—far less, for example, than in a glass of milk. Although the amounts will vary from batch to batch, a typical cup of beef stock (or bone broth) has about as much calcium as a half cup of broccoli.
Bone broth does contain relatively large amounts of collagen, a specialized protein that is found in skin and connective tissue. The idea is that collagen—which is also known as gelatin—will strengthen and rebuild the cartilage in our joints and plump up our sagging skin. However, the science to support this is fairly weak. Collagen is a large protein and it gets broken down into much smaller peptides by the digestive system before being absorbed. As far as your body is concerned, collagen is probably no better or worse for your joints or skin than any other type of protein.
Nonetheless, if it's collagen you're after, you want to make your bone broth with raw bones and not roasted bones, as is sometimes suggested. Although roasting the bones before you boil them may improve the flavor of your broth, it also denatures much of the collagen, so you'll end up with far less of it in your stock.
You can actually see this with the naked eye, by the way. Stock made from raw bones is much more viscous than stock made from roasted bones. I've made stock from raw bones that contained so much collagen that it actually resembled jelly when it cooled! Sadly, however, it did not make a noticeable difference in the plumpness of my skin or my runner's knee pain. Then again, I didn't expect it to...and that often makes all the difference!
The claims for bone broth as a sleep or memory aid appear to be based on the purported glycine content, one of the amino acids found in collagen. The body can actually manufacture glycine from other amino acids, so it's not considered essential to our diets. But one study found that giving subjects 3 grams of pure glycine on an empty stomach at bedtime led to modest improvements in fatigue the next day.
It’s hard to say exactly how much collagen (or glycine) is in a given batch of bone broth but it would probably take quite a bit of broth to get 3 grams of glycine. Moreover, consuming glycine in the presence of all the other amino acids in the bone broth would probably negate the effect. I’m tempted to say that people who notice a difference in their sleep quality when they drink bone broth might be experiencing a placebo effect.
I've saved the most interesting claim for last: Proponents of bone broth often claim that it can enhance immune function. And, in fact, I was able to track down studies that offer some support for this claim...well, sort of. These studies didn't use bone broth. (There don't seem to be any published studies using bone broth.) And the studies didn't demonstrate enhanced immune function.
These studies used collagen supplements in patients suffering from rheumatoid arthritis. As you may know, RA is an auto-immune disease in which the body's immune system mistakes its own joint tissue for a foreign invader and tries to destroy it. These studies found that exposing the patients to collagen in the form of an oral supplement seemed to somehow desensitize the patient's immune systems to their own native collagen, reducing their symptoms.
Now, if I or someone I loved suffered from rheumatoid arthritis, I'd be making chicken stock by the gallon! But, unfortunately, these studies don't suggest that collagen (and therefore, bone broth) will heal arthritis or strengthen the immune system. For one thing, rheumatoid arthritis is a completely different disease process than the kind of arthritis that most people suffer from. More importantly, therapies that help with auto-immune conditions are usually not immune-boosting substances. In most cases, they work by suppressing the immune response.
Bone broth's reputation as a magical health elixir seems to be based almost entirely on anecdotal reports and just good old-fashioned hype and exaggeration. That said, it's a tasty and nutritious food and would make a valuable addition to a healthy balanced diet. It makes good use out of parts of the animal that might otherwise go to waste. Unless you are a vegetarian, I see absolutely nothing wrong with consuming it on a regular basis.
And if it makes you feel like superman (or superwoman), so much the better!
Bannai M, Kawai N, et al. The effects of glycine on subjective daytime performance in partially sleep-restricted healthy volunteers. Front Neurol. 2012 Apr 18;3:61.
Barnett ML, Kremer JM, et al. Treatment of rheumatoid arthritis with oral type II collagen. Results of a multicenter, double-blind, placebo-controlled trial. Arthritis Rheum. 1998 Feb;41(2):290-7.
Barnett ML, Combitchi D, Trentham DE. A pilot trial of oral type II collagen in the treatment of juvenile rheumatoid arthritis. Arthritis Rheum. 1996 Apr;39(4):623-8.
Trentham DE, Dynesius-Trentham RA, et al. Effects of oral administration of type II collagen on rheumatoid arthritis. Science. 1993 Sep 24;261(5129):1727-30.
Zhang LL, Wei W, et al. A randomized, double-blind, multicenter, controlled clinical trial of chicken type II collagen in patients with rheumatoid arthritis. Arthritis Rheum. 2008 Jul 15;59(7):905-10.