Cinnamon is a common household spice used to add warmth and flavor to foods, yet it is also the subject of a widespread belief regarding its potential to start or speed up labor. Many expectant individuals search for natural ways to encourage the birthing process, leading them to investigate this spice. The idea is that consuming cinnamon, often in high concentrations like a tea or capsule, can stimulate the uterus to contract. This article examines the historical basis for this claim and details the current scientific understanding of cinnamon’s effects on the body, particularly the uterus.
Why Cinnamon is Believed to Induce Labor
The belief that cinnamon can induce labor stems from its long history of use in traditional and folk medicine practices. In various cultures, the spice has been classified as a warming agent or general bodily stimulant. Traditional medicine systems, such as those found in Mexico, have historically utilized the spice as an emmenagogue, a substance thought to stimulate or increase menstrual flow.
This traditional use blurred the lines between stimulating menstruation and stimulating the uterus for childbirth. Cinnamon has also been cited as an abortifacient or an oxytocic agent, meaning it was believed to promote uterine contractions. The idea is often grouped with other strong or spicy foods, where generalized stimulation of the digestive system is anecdotally associated with stimulating the nearby uterine muscles. This strong traditional context created the foundation for the modern claim that cinnamon can reliably start labor.
The Scientific Consensus on Uterine Effects
Scientific investigation into cinnamon’s effect on the uterus suggests that normal consumption does not induce labor. The primary active compound in cinnamon is cinnamaldehyde, which gives the spice its characteristic flavor and aroma. Research has focused on whether this compound or other extracts possess oxytocic properties, which are necessary to stimulate the strong, coordinated contractions required for labor.
Interestingly, several laboratory studies using isolated rat uterine strips have demonstrated a contradictory effect. These studies found that cinnamon extract actually decreased the force of uterine contractions, even when the contractions were chemically induced by oxytocin, the hormone responsible for labor. This finding suggests that cinnamon may act as an antispasmodic or a tocolytic agent, a substance that inhibits uterine contractions, rather than one that induces them.
The proposed mechanism for this effect is the inhibition of L-type calcium channels, which limits the influx of calcium ions necessary for muscle contraction in the uterus. Therefore, the available scientific evidence does not support the idea that consuming cinnamon will start labor. Any reported instance of labor beginning after cinnamon consumption is likely a coincidence.
Safety Concerns and Recommended Intake
When considering consuming cinnamon in large amounts to attempt labor induction, the focus shifts from the question of efficacy to one of safety. The main concern for pregnant individuals is the presence of a naturally occurring compound called coumarin, which can be toxic to the liver in high concentrations. Coumarin content varies dramatically between the two main types of cinnamon available commercially.
Cassia cinnamon, which is the most common and least expensive variety sold in the United States, contains significantly higher levels of coumarin. By contrast, Ceylon cinnamon, often labeled as “True Cinnamon,” contains only trace amounts of the compound, making it the safer choice for regular or high consumption. The European Food Safety Authority (EFSA) established a tolerable daily intake (TDI) of coumarin at 0.1 milligrams per kilogram of body weight.
Consuming large, medicinal quantities of Cassia cinnamon, such as in supplements or excessive tea, can easily exceed this safe limit, potentially posing a risk of liver damage. Healthcare providers recommend that pregnant individuals limit their intake of Cassia cinnamon to no more than about one-half teaspoon daily. Cinnamon supplements and essential oils should be avoided entirely during pregnancy due to their highly concentrated and unregulated levels of active compounds.