Bone broth is a liquid derived from the slow-simmering of animal bones, connective tissues, and sometimes vegetables, a process that extracts compounds like collagen, gelatin, and various amino acids. It has gained widespread attention in health circles due to its purported benefits for joint health and the digestive system. However, for some people, consuming this concentrated liquid leads to an unexpected and uncomfortable reaction, most notably diarrhea or general digestive upset. This analysis explores the specific reasons why this food can sometimes trigger adverse gastrointestinal symptoms.
Primary Reasons for Digestive Distress
One of the most common mechanical factors contributing to digestive issues is the high fat content present in many homemade or unskimmed broths. When bone broth is simmered for long periods, fat from the marrow and surrounding tissue leaches into the liquid. Ingesting a large amount of fat at once stimulates the gallbladder to release bile to aid in digestion. If the fat content is excessively high, the digestive system may not fully absorb all the bile. The excess bile then reaches the colon, where it acts as a natural laxative, leading to loose stools or diarrhea.
The sheer richness and concentration of the broth can also overwhelm a digestive system unaccustomed to it. Rapidly introducing a concentrated source of protein and gelatin, especially in large volumes, can increase intestinal motility. This acceleration of movement shortens the time available for water and nutrients to be properly absorbed through the bowel wall.
The long cooking process can also draw out a high concentration of certain minerals, affecting the osmotic balance in the gut. While bone broth provides beneficial electrolytes, a high intake of minerals like magnesium can have a laxative effect. Magnesium works by drawing water into the intestines, softening the stool and stimulating bowel movements, which can cause watery diarrhea.
Specific Compound Sensitivities
Sensitivities to specific chemical compounds found in bone broth can trigger a direct inflammatory or motility response. Bone broth is naturally rich in the amino acid glutamine, which converts from glutamic acid during cooking. While glutamine is often beneficial for repairing the gut lining, a high concentration can adversely affect individuals with gut dysbiosis or heightened sensitivity. This high dosage may stimulate rapid gut movement or be metabolized by certain bacteria, causing discomfort or a paradoxical diarrheal reaction.
A frequently overlooked biological trigger is the high level of histamine that develops during the long simmering time. Bone broth is typically simmered for 12 to 72 hours, significantly elevating its histamine content. For people with a deficiency in the enzyme diamine oxidase (DAO), which breaks down histamine in the digestive tract, consuming this high-histamine food can trigger a systemic reaction. This reaction often includes allergy-like symptoms such as cramping, bloating, and diarrhea.
A final consideration, particularly with store-bought broths, involves hidden flavor enhancers. Many commercial recipes add high-FODMAP ingredients, such as onion or garlic powder or concentrates, to improve the flavor profile. Fructans in these ingredients are poorly absorbed and are rapidly fermented by gut bacteria in the colon, producing gas and drawing water into the bowel. For individuals with Irritable Bowel Syndrome (IBS), these high-FODMAP additions are a common and severe trigger for pain, bloating, and diarrhea.
Adjusting Consumption to Prevent Issues
To mitigate the risk of digestive distress, the most effective strategy is to introduce the broth gradually to allow the digestive system time to adapt to the new nutritional load. Begin by consuming a very small serving, such as a quarter of a cup, and slowly increase the amount over several days or a week. This measured approach helps prevent the immediate overwhelming of the digestive tract.
If fat content is suspected as the cause, a simple intervention is to chill the broth thoroughly after cooking. As the broth cools, the fat will solidify on the surface, allowing you to easily skim and discard the layer before reheating and consuming the liquid. This reduces the bile-stimulating effect and the potential laxative action.
Individuals concerned about histamine sensitivity can modify preparation by reducing the simmering time to under eight hours, limiting histamine accumulation. If high-FODMAP ingredients are a concern, scrutinize commercial labels or make a homemade version using low-FODMAP alternatives like the green parts of scallions or chives.
Pay close attention to the body’s reaction. If symptoms like persistent pain, bloody stool, or signs of severe dehydration occur, stop consumption immediately and consult a healthcare provider. While temporary loose stools may signal adaptation, severe or prolonged diarrhea warrants professional medical advice.