The digital event, broadcast Jan. 27, examined how the gastrointestinal system functions in female athletes, how it changes across the lifespan and menstrual cycle, and the ways gut health influences performance, recovery, immunity, and overall well-being.
Gut health and the female athlete
Research shows that a more diverse gut microbiota aids digestion and nutrient absorption by helping to break down fibers and carbohydrates.
“It supports the absorption of key nutrients such as iron, calcium, magnesium and B vitamins,” said Grainne O’Higgins, sports dietitian and host of the event. “These nutrients are particularly at risk of deficiency in female athletes.”
Gut health is especially important for female athletes for several reasons, she continued, noting that one key factor is its influence on estrogen metabolism.
“Reduced gut microbiota diversity or imbalances in gut bacteria can disrupt estrogen regulation, which may contribute to menstrual irregularities, increased PMS severity, and potential impacts on cardiovascular health, bone health, immune function and recovery,” O’Higgins said.
The gut microbiota also plays a role in energy availability. Certain gut microbes help extract energy from food and support effective fueling. However, imbalances in these microbes, particularly when combined with under-fueling or low energy availability, can impair digestion, reduce nutrient absorption, increase fatigue risk and trigger gastrointestinal symptoms, O’Higgins explained.
In addition, a healthy gut microbiota can help protect against exercise-induced gut symptoms by reducing gut inflammation and improving tolerance to food and fueling during training and competition. It also plays a significant role in the gut–brain axis. Gut microbes actively communicate with the brain, influencing mood, stress and inflammation.
Hormonal changes that occur across the female lifespan
In adolescence and adulthood, rising estrogen and progesterone create sex-specific differences in the gut microbiota. As the gut matures, lifestyle factors such as diet, training load, sleep and stress increasingly influence gut health.
“By understanding the different phases of the cycle and the symptoms that may arise, we can develop practical strategies to manage them and minimize their impact,” said O’Higgins.
Gut patterns change across the menstrual cycle as hormone levels fluctuate. During the menstrual phase, low estrogen and progesterone and rising prostaglandins increase bowel contractions, often causing looser stools, diarrhoea, cramping, bloating, nausea, and worsened IBS symptoms.
In the follicular phase, estrogen gradually rises while progesterone remains low, supporting stable digestion, healthy gut motility and gut barrier function. Around ovulation, peak estrogen and a surge in luteinizing hormone promote efficient smooth muscle coordination, so gastrointestinal disruption is usually minimal.
During the luteal phase, higher progesterone slows gut motility, increasing the likelihood of constipation, bloating and gas. In the premenstrual phase, a rapid drop in estrogen and progesterone increases prostaglandin activity and gut sensitivity, which can shift bowel patterns from constipation to diarrhoea in some individuals.
“Recognizing these patterns means we can manage symptoms more effectively during training, which in turn helps optimize training quality and recovery,” O’Higgins said. “And for athletes experiencing menstrual-related gastrointestinal symptoms, targeted nutritional strategies may help alleviate symptom severity.”
Nutrients that may ease menstrual cramps and GI discomfort
Research suggests that omega-3 fatty acids may be beneficial due to their anti-inflammatory properties. Omega-3s can help modulate prostaglandin production, which plays a key role in menstrual pain and inflammation, and may therefore reduce associated GI cramping and discomfort.
Magnesium supplementation may also support symptom management, O’Higgins added. Magnesium plays a role in smooth muscle relaxation, neuromuscular function and stress regulation, and deficiencies have been associated with increased menstrual cramping and constipation.
In addition, polyphenol-rich foods may contribute to symptom relief through their antioxidant and anti-inflammatory effects, as well as their potential role in supporting gut microbiota diversity, O’Higgins noted.
Finally, some probiotics have shown promise in supporting gut health in female athletes. Species such as Lactobacillus rhamnosus and Lactobacillus plantarum can help strengthen gut barrier function, improve gut motility and reduce exercise-induced gastrointestinal symptoms. Lactobacillus acidophilus can also support digestion and nutrient absorption, including minerals such as calcium and magnesium.
As with all nutritional interventions, it is “important that these strategies are individualized, taking into account the athlete’s symptom profile, dietary intake, training demands and tolerance,” O’Higgins said.
