According to the Centers for Disease Control, sixty-nine percent of Americans are overweight, with about thirty-five percent obese despite massive public health initiatives, booming sales of weight loss products and bestselling new diet books.
Over the years, numerous diet books have stressed the importance of soup in weight loss programs. However, the reasoning has rarely transcended the commonsense idea that filling up on broth means less room for dinner and dessert. That may well be the case, and at least one study has shown a lower calorie intake with soup on the menu, but there are other sound scientific reasons for this recommendation as well.
Broth improves the digestibility and assimilation of food, giving the body the critical message that it is deeply nourished, happy and full. Individuals who feel physical and emotional satisfaction from their food also experience fewer cravings for sugar and starchy carbohydrates. That not only influences the attainment and maintenance of a healthy weight but minimizes the likelihood of developing diabetes or other blood sugar issues that contribute to the condition Mark Hyman, MD, has dubbed “diabesity.” With gut-healing we also are able to house more beneficial microflora, which, in turn, bring reduced storage of carbohydrates as body fat. In contrast, poor gut bacteria increase insulin production, leading to insulin resistance and increased storage of body fat.
Now research from Brazil suggests the glutamine in broth could help build a healthy microbiome. Glutamine is a “conditionally essential” amino acid found abundantly in broth that often comes up short in the Standard American Diet (SAD) as well as in plant-based diets. It can even prove scarce in primal diets if people forget “nose to tail” eating and overemphasize their consumption of steaks, chops and other muscle meats.
The Brazilian researchers discovered that a daily dose of 30 grams of glutamine significantly reduced the ratio of Firmicutes to Bacteroidetes bacteria in obese and overweight people. The F to B ratio has been a hot area of research at least since 2005 when Jeffrey Gordon and colleagues at Washington University in St. Louis discovered lower levels of Bacteroidetes and higher levels of Firmicutes in obese mice compared to lean mice. A year later Gordon’s team announced similar findings in obese humans.
The recent glutamine study involved 33 overweight or obese adults aged 23 to 59 with a BMIs (body mass index) ranging from 26 to 47. The researchers found that F to B ratio decreased from 0.85 to 0.57 in the glutamine group and increased from 0.91 to 1.12 in the control group, which received 30 grams of L-alanine. What the Brazilian study didn’t show was weight loss, which is hardly surprising given the fact that the study lasted all of fourteen days. Whether a long-term — or even longer-term — study will result in metabolic changes leading to permanent weight loss remains to be seen.
Another relevant study on glutamine and the microbiome was published in 2012 by Zhao-Lai Dai and colleagues at the Laboratory of Gastrointestinal Microbiology at Nanjing Agricultural University in Nanjing, China. It suggested glutamine regulates how gut bacteria assimilate and utilize amino acids, particularly arginine. Because supplemental glutamine can fulfill the needs of pathogenic bacteria, glutamine feeding can minimize their detrimental effect on amino acid availability for the host, with overall improvements in health.
The finding that glutamine may benefit gut microbiota adds to a long list of beneficial health effects found for glutamine by researchers over many years. Muscle loss, accelerated wound healing, gut healing, immune system modulation, and the production of human growth hormone are just a few of those many benefits. Glutamine is the third most abundant amino acid found in bone broth and gelatin. Textbooks tell us it’s a “non essential” amino acid because the body can manufacture it as needed. The ability to manufacture it easily and abundantly, however, is probably true only of those rare people who enjoy radiant good health. In reality, most people today are so stressed physically and mentally that they can benefit greatly from increasing their supply of glutamine. Obviously glutamine supplements are an option, but the “real food” source is bone broth.
De Souza AZ, Zambom AZ, et al. Oral supplementation with l’glutamine alters gut microbiota of obese and overweight human adults: a pilot study. Nutrition Journal, Published Online: January 29, 2015, http://www.nutritionjrnl.com/article/S0899-9007(15)00035-0/abstract Full text available at Research Gate: https://www.researchgate.net/publication/272198125_Oral_Supplementation_with_L-Glutamine_Alters_Gut_Microbiota_of_Obese_and_Overweight_Human_Adults_A_Pilot_Study
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