Bone Broth Review
Initial Posting: 3/25/18 Last Update: 6/15/18
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- What is it? Bone broth (made from simmering chicken or beef bones) can be a good source of protein — particularly collagen. Although vitamins and minerals are naturally found in bone broth, amounts are small — less than 5% of daily requirements. The mineral found in highest concentration is potassium. (See What It Is). Sodium naturally occurring in bone broth is about 100 to 150 mg per cup, but some have added salt, boosting levels to about 500 mg.
- What does it do? Although there is not much clinical information about the effects of bone broths, research with collagen suggests that it may help with joint pain and modestly improve skin elasticity and reduce wrinkles. The protein in bone broth also contributes to one's daily requirement for protein. (See What It Does).
- What CL found: The bad news: One product contained only 38% of its claimed protein and 75% more sodium than listed. The good news: All other products met their label claims for protein and sodium and none exceeded stringent limits for contamination with heavy metals. However, CL found large differences in the amounts of protein and collagen in products and the cost to obtain them. To obtain 5 grams of collagen, for example, the cost ranged from just 56 cents to $9.99. (See What CL Found). Powered bone broths, in general, cost only one-quarter that of ready-to-drink bone broths. Chicken bone broths are about half the price of beef bone broths — although more of the protein in beef broths tends to be collagen.
- Best choice? Based on results of our laboratory and taste tests, as well as cost, CL chose 4 products as its Top Picks.
What It Is:
Bone broth is made by simmering bones and cartilage (typically chicken or beef bones which have been stripped of most or all of their meat) in water for an extended period of time. The resulting liquid contains significant amounts of protein, potassium, and sodium (and much smaller amounts of other vitamins and minerals such as calcium) which have leeched from the bones. (Note: Potassium is not currently listed on many labels as its inclusion is voluntary until new labeling laws take effect). Perhaps most importantly, bone broth can be a rich source of collagen, the main protein found in bone. In fact, as found in this Review, about 40 to 80% of the protein in bone broths was collagen (see Results table for amounts found in the products tested in this Review).
Bone broth (known as "stock" in traditional culinary terms) differs from regular "chicken broth" or "beef broth" in that it is the liquid of simmered bones, whereas "chicken broth" or "beef broth" is the liquid of simmered meat (on or off the bone) — making bone broth likely to contain more collagen than regular broth. (Be aware that most bone broth products list "beef broth" or "chicken broth" as their primary ingredient and not "bone broth," although some mention that the broth is made from "bones.")
Bone broth is sold as a liquid, powder (produced by dehydrating liquid bone broth) that can be mixed with water to drink, or powder encapsulated in pill form.
What It Does:
Although bone broth products are often promoted for a wide range of health benefits, from boosting the immune system and healing the digestive tract to reducing joint pain and reducing or preventing wrinkles, there is little research specifically on the effects of bone broth products.
However, as noted, bone broth products are generally a good source of protein, especially collagen. Protein is an essential macronutrient for muscle growth and maintenance and bone broth can contribute to your daily requirement for protein which depends largely on your weight and level of activity. A 150 lb person, for example, requires 60 grams to 109 grams daily activity (see Protein Powders Review for more about protein requirements). There is no daily requirement for collagen, although studies on the effects of collagen supplementation suggest potential benefits, as described below.
Also, be aware many of the studies on collagen, discussed below, used specific forms of collagen, and most bone broth liquids and powders do not list the form of collagen they contain on the label. Collagen hydrolysate (enzymatically hydrolyzed collagen or collagen peptide), one of the most commonly studied forms, is collagen which has been broken down into smaller peptides. Two other types of collagen that are also sold as supplements are collagen in its more raw "undenatured" form and gelatin -- which is derived from collagen but is not broken down as completely to peptides as enzymatically hydrolyzed collagen. The majority of the collagen found in bone broth is likely to be gelatin. Although undenatured collagen, gelatin, and collagen hydrolysate may all be broken down in the gut to yield absorbable amino acids, studies in mice suggest that absorption may be greater with hydrolyzed collagen (collagen hydrolysates), due to its smaller molecular size. Collagen is sometimes classified as type 1 (which is most abundant in connective tissue and a common source of collagen hydrolysate) or type II (found most abundantly in cartilage). In this review, just two products listed the types of collagen they provide: Jarrow Formulas Beyond Bone Broth Powdered Drink Mix lists types I and II, and Ancient Nutrition Bone Broth Protein lists type II.
Bone broth is often promoted for boosting the immune system or helping to reduce cold symptoms; however, these claims appear to be based on two very preliminary studies which used chicken soup, not bone broth specifically. One small laboratory study (frequently cited as evidence of the immune "boosting" benefits of bone broth protein) found that traditional chicken soup (including vegetables) inhibited the movement of neutrophils (a type of white blood cell). This movement is normally part of the immune-system's inflammatory response, suggesting a possible anti-inflammatory effect, but not an immune "boosting" effect (Bo, Chest 2000). A study among 15 healthy young adults who did not have a respiratory infection found that compared to sipping cold water, sipping either hot (149° F) water or chicken soup increased the movement of nasal mucus in the nose, although the chicken soup was slightly more effective; the effect lasted for less than 30 minutes. (Saketkhoo, Chest 1978).
There are no published clinical studies on the use of bone broth products for arthritis or joint pain. However, bone broth products can be a good source of collagen and several studies suggest collagen may be beneficial.
Supplements with collagen hydrolysate (typically 10 to 12 grams per day) or gelatin may help reduce pain associated with osteoarthritis when taken for several months (preferably at least 6 months). In fact, one study suggested greater benefit with collagen hydrolysate than with glucosamine sulfate (Trc, Intl Orthop 2011). However, larger studies are needed to confirm this effect and some people may experience mild gastrointestinal side effects.
One of the largest studies with collagen hydrolysate found that, after 3 months, it was not more effective than placebo in reducing joint pain (of the hip, knee, elbow, shoulder, hand or/and lumbar spine), but after 6 months there was a statistically significant difference: 51.6% of people taking the collagen (Genacol, Genacol Corporation Inc.) reported a reduction in pain compared to 36.5% of those taking placebo (Bruyere, Comp Ther in Med 2012). A small study published in 2014 in people with knee osteoarthritis found that taking 5 grams of collagen hydrolysate (collagen peptide) dissolved in a cup of water or milk in the morning and at night after food for 13 weeks significantly improved symptoms compared to taking a placebo (Kumar, J Sci Food Agric 2014).
There is very limited evidence that collagen may help for rheumatoid arthritis.
Collagen may also help to reduce joint pain associated with physical activity in healthy active adults. A study among 97 young men and women (average age 20) who were members of a college varsity team or sports club and who had joint pain or joint discomfort due to joint stress, injury, surgical outcome, or trauma, found that 10 grams of liquid collagen hydrolysate taken daily for approximately 5 months significantly reduced joint pain at rest (as assessed by a physician) and self-reported joint pain when running and walking compared to placebo. The study was funded by the maker of the collagen used in the study (GELITA Health GmbH, Germany) (Clark, Curr Med Res Opin 2008). Another study in Germany funded by GELITA found that 5 grams of collagen peptides taken daily for six months by male and female athletes (average age 27) with chronic ankle instability (pain, weakness and general instability as a result of ankle sprains) led to improved self-reported ankle stability and function, and decreased pain and swelling, compared to placebo. The number of athletes reporting ankle sprains during a three-month follow-up period was also lower in the group that had taken collagen compared to the group that had taken placebo (9 vs. 24) (Dressler, J Sports Sci Med 2018).
Bone health and osteoporosis
In mice, it has been found that after intestinal absorption, peptides from collagen hydrolysate accumulate preferentially in cartilage and bone; animal studies have also found collagen hydrolysate supplementation to have beneficial effects on bone and to increase bone mineral density (Fanaro, Rev Bras Geriatr Gerontol 2016). There are few studies on the effects of collagen supplementation on bone health in people. A single study in the Czech Republic among 97 postmenopausal women ( > 40 years old) with radiologic evidence of osteoporosis and bone mineral density of less than 80% found that taking 10 grams of collagen hydrolysate daily, in addition to treatment with calcitonin (a hormone that can modestly increase bone mass) for approximately six months was more effective in inhibiting bone collagen breakdown than calcitonin alone; however, this did not lead to statistically significant increases in bone mineral density (Adam, Cas Lek Cesk 1996).
There is also some evidence collagen may help to build muscle and increase muscle strength in older adults when combined with exercise. In a study among older men (average age 72) with sarcopenia (age-related muscle loss) who participated in a strength training program 3 days per week for 3 months, those who consumed a daily drink containing 15 grams of collagen peptides (BODYBALANCE, GELITA AG) had significantly greater increases in lean muscle mass and muscle strength compared to those who consumed a placebo drink (Zdzieblik, Br J Nutr 2015). There are also many studies with protein supplements showing similar benefits when combined with exercise.
Skin, wrinkles and nails
The best evidence supporting the use of collagen in aging skin is with VERISOL (Gelita AG), a collagen peptide made of hydrolyzed, porcine-derived type I collagen. Several studies have been conducted, all of which used VERISOL as a powder mixed with water. The most notable study focused on crow's feet wrinkles around the eyes of women ages 45 to 65. At 4 weeks of treatment with 2.5 grams of VERISOL daily, eye wrinkle volume was reduced by 7.2% in comparison to placebo and, at 8 weeks, by 20.1%. Even 4 weeks after treatment, wrinkle volume had decreased 11.5% more than placebo. In addition, fluid extracted from skin (of the inner arm) showed that procollagen type I content increased by 65% compared to placebo after 8 weeks of treatment and elastin increased by 18%. All of these findings were statistically significant (Proksch, Schunck, Skin Pharmacol Physiol 2014).
Another study among women (average age 48) found those who took 2.5 grams or 5.0 grams of VERISOL daily for two months had a modest improvement in skin elasticity of the inner forearms, but no improvement in skin roughness or increase in hydration, compared to placebo. Among those who took the collagen supplement, increased skin elasticity was greatest in women who were over age 50; both doses were equally effective (Proksch, Segger, Skin Pharmacol Physiol 2014). The collagen was given as a powder and added to water. A small study among men and women in Japan found that three grams of collagen peptides taken daily for three months modestly improved skin hydration and elasticity compared to placebo (Choi, J Cosmet Laser Ther 2014). The addition of 500 mg of vitamin C to the collagen peptides did not enhance these effects. (See more information about collagen supplements for skin and wrinkles.)
A study in Brazil suggested a benefit for brittle nails from a collagen supplement. However, there was no placebo control in the study, making the findings questionable. Women in the study consumed 2.5 grams per day of bioactive collagen peptides (BCP, VERISOL) dissolved in water for 24 weeks. Nail growth was reported to have increased by 12% and the frequency of broken nails decreased by 42% compared to the period before collagen treatment. There was no significant change in nail roughness (i.e., ridging and grooves) (Hexsel, J Cosmet Dermatol 2017).
Gut health and digestive disorders
Bone broth is often promoted for healing the gut and treating various digestive disorders, including "leaky gut syndrome" (increased intestinal permeability). Laboratory and animal studies suggest that a combination of gelatin and tannic acids (gelatin tannate) may help to reinforce the mucous lining of the gut and reduce symptoms of colitis (Frasca, Clin Exp Gastroenterol 2012; Scaldaferri United European Gastroenterol J 2014). Gelatin tannate, in combination with proper rehydration, has also been shown to effectively treat diarrhea in children (Cagan, Med Sci Monit 2017), and is sold in some countries for this use. However, it's not clear if gelatin or collagen taken alone would have this effect. Another study found that, compared to healthy individuals, people with ulcerative colitis and Crohn's disease tended to have lower blood levels of collagen (Koutroubakis, J Clin Pathol 2003). However, there does not appear to be any research on the effects of bone broth or collagen supplementation in people with leaky gut syndrome, ulcerative colitis, Crohn's disease, or other digestive conditions.
Quality Concerns and What CL Tested for:
As no government body normally tests bone broth supplements, ConsumerLab.com purchased and tested products to determine whether they contained their claimed amounts of protein and sodium and how much collagen they contained (not listed on most product labels).
Products were also tested for contamination with lead, cadmium, arsenic and mercury, as heavy metals can accumulate in animal bones and cartilage and one small study found significant amounts of lead (7 mcg per liter [about 4 cups] in broth made from "organic" chicken) (Monro, Med Hypotheses 2013). Interestingly, that study found only 1/3 as much lead in broth made with just chicken "meat" as compared to broth with meat and bones, but 35% more lead in broth made with just chicken cartilage and skin.