Intermittent fasting (IF) is a popular health strategy that involves cycling between periods of eating and abstaining from food. As people seek to maintain a fasted state, confusion often arises regarding low-calorie liquids, and chicken broth is a common item of debate. Determining if this savory liquid interrupts the fasting process depends entirely on the specific goals a person is trying to achieve with their fast.
What Defines a Broken Fast
A fast is considered broken when the body’s metabolic state shifts from utilizing stored fat for energy back to processing recently consumed nutrients. This shift is primarily driven by the release of the hormone insulin. When we consume carbohydrates or protein, insulin levels typically rise to manage the influx of glucose and amino acids.
For those practicing IF for general weight loss or metabolic health, a common rule of thumb is the caloric threshold. Consuming less than 50 calories during the fasting window will not significantly disrupt the benefits of fat burning or ketosis. However, the source of these calories is important, as carbohydrates and proteins have a greater insulin-triggering effect than fat.
For individuals seeking the deeper cellular cleanup process called autophagy. Autophagy is a state of cellular recycling that appears to be highly sensitive to nutrient intake. Even a minimal intake of protein, specifically amino acids, can inhibit this process. Therefore, a fast intended for maximal autophagy is “broken” by almost any caloric intake, necessitating a water-only approach.
Nutritional Components of Broth
Standard chicken broth is typically made by simmering chicken meat and bones for a relatively short time, often less than two hours. This results in a liquid that is very low in overall calories, frequently containing fewer than 10 calories per cup.
It is primarily valued during fasting for its water content and essential minerals like sodium and potassium, which help maintain electrolyte balance. Packaged or concentrated broths should be checked for hidden ingredients such as yeast extracts, added sugars, or flavorings, which can unknowingly increase the caloric or carbohydrate count.
Bone broth, on the other hand, is made by simmering bones for a much longer period, sometimes up to 24 hours. This extended cooking time extracts significantly more protein, primarily in the form of collagen and gelatin, yielding a higher concentration of amino acids. A cup of bone broth can contain 40 to 50 calories and several grams of protein. This higher protein content is the main difference, giving bone broth richer nutrients for joint and gut health, but also making it more metabolically active than standard chicken broth.
Broth’s Metabolic Impact on Fasting Goals
Standard chicken broth is generally permissible. Since a typical serving contains well under the 50-calorie threshold and has minimal protein or carbohydrates, it is unlikely to trigger a significant insulin response. Consuming this low-calorie liquid can also help manage hunger and replenish electrolytes, making the fasting window more sustainable.
The primary goal is maximizing autophagy. The protein content in any broth, particularly the higher levels of amino acids found in bone broth, can signal to the body that nutrients are available. Therefore, for a strict, therapeutic fast focused on autophagy, even a small amount of bone broth with its 40 to 50 calories and protein is considered a fast-breaker.
For those fasting to reduce overall calories and promote fat burning, a low-calorie, low-protein chicken broth is acceptable. It serves as a helpful tool for hydration and mineral intake without substantially interrupting the body’s metabolic state. If the intent is to achieve the deepest level of cellular cleaning and renewal, water-only is necessary, and any form of broth should be reserved for the eating window.