May 2016 Issue

Ask the Expert: What's the Deal With Bone Broth?
By Toby Amidor, MS, RD, CDN
Today's Dietitian
Vol. 18 No. 5 P. 10

Q: Some of my clients have begun eating bone broth. Many are asking me about ways to prepare it and if it really can boost immunity, aid digestion, relieve arthritis, detox the liver, and improve wound healing. Can you explain what bone broth is, what nutrients it contains, and if there's any truth to its proposed health benefits?

A: Bone broth is a cross between a stock and a broth and has taken on the label of a "superfood" in popular culture. However, there's a lack of scientific evidence about the claims. Furthermore, one study warned that overconsumption of bone broth may even be harmful. Here's what nutrition professionals should know if they recommend bone broth to clients.

What Is It?
For comparison, broth is water simmered with vegetables, meat, herbs, and spices, and it may include bones. It's usually cooked for 45 minutes to two hours, then strained and seasoned. Stock is water simmered with vegetables (typically carrots, onions, and celery) and animal bones (chicken, beef, fish), sometimes with meat. It's cooked for four to six hours, then strained. Bone broth, on the other hand, usually is made from roasted bones, sometimes with the meat attached, and vegetables. Typically it's cooked for more than 24 hours, then strained and seasoned.

Just as broth and stock recipes vary, so can bone broth, which means the nutritional composition also can differ. According to the USDA Nutrient Database, an analysis for bone broth isn't available; however, there's a nutrient analysis for homemade chicken stock.1 One cup contains 86 kcal, 6 g protein, 2.9 g total fat, and 8.5 g carbohydrates. It also contains 7 mg calcium, 0.5 mg iron, 10 mg magnesium, 252 mg potassium, 0.34 mg zinc, and 343 mg sodium. Packaged bone broth also varies in nutrient composition. Pacific Foods Chicken Bone Broth, for example, contains 9 g protein per cup and contains no iron or calcium.

Health Benefits
There's little evidence on the health benefits of bone broth, including benefits for digestive health. According to Kate Scarlata, RDN, LDN, owner of For a Digestive Peace of Mind, a nutrition consulting practice in Medway, Massachusetts, "I have not seen any research to support the use of bone broth for gut health. There are many claims out there. Just like chicken soup, I am sure it provides nourishment, but consuming bone broth three times a day [is] probably not warranted and may be risky—especially in kids."

According to a 2013 study published in Medical Hypotheses, bones are known to sequester heavy metals, and bone broth may carry a risk of lead contamination.2 The study authors recommend nutrition professionals keep this risk in mind if recommending bone broth to clients, especially children.

There may be, however, some health benefits to consuming chicken soup made with meat and vegetables, which is somewhat similar to bone broth. A 2000 study published in Chest concluded that soup may provide a mild anti-inflammatory effect that can help mitigate symptoms of upper respiratory infections.3

Recommendations for Clients
If clients choose to consume bone broth, Bonnie Taub-Dix, MA, RDN, CDN, owner of BetterThanDieting.com and author of Read It Before You Eat It: How to Decode Food Labels and Make the Healthiest Choice Every Time recommends the following:
• Watch the sodium content, as not all bone broths are created equal.
• Beware of hidden ingredients, including unexpected calories from cream, butter, or oil.
• Add vegetables or whole grains to bone broth to increase its nutritional value.

— Toby Amidor, MS, RD, CDN, is the founder of Toby Amidor Nutrition (http://tobyamidornutrition.com) and the author of the cookbook The Greek Yogurt Kitchen: More Than 130 Delicious, Healthy Recipes for Every Meal of the Day. She's also a nutrition expert for FoodNetwork.com and a contributor to US News Eat + Run, Shape.com and MensFitness.com.

References
1. Basic report: 06172, soup, stock, chicken, home-prepared. USDA Agricultural Research Service website. https://ndb.nal.usda.gov/ndb/foods/show/1305?fgcd=&manu=&lfacet=
&format=&count=&max=35&offset=&sort=&qlookup=chicken+stock
. Accessed March 7, 2016.

2. Monro JA, Leon R, Puri BK. The risk of lead contamination in bone broth diets. Med Hypotheses. 2013;80(4):389-390.

3. Rennard BO, Ertl RF, Gossman GL, Robbins RA, Rennard SI. Chicken soup inhibits neutrophil chemotaxis in vitro. Chest. 2000;118(4):1150-1157.