No one knows the exact reason for irritable bowel syndrome (IBS), a digestive disorder that is more common in women, affecting from 1.5 to 3 times more than men. It causes stomach pain, cramps, and bloating, as well as diarrhoea and constipation.

Sex hormones and IBS

Both ostrogen and progesterone affect IBS symptoms in a few ways, from how your intestines work to how much pain you feel. A growing body of research shows that sex hormones, like oestrogen and progesterone, may be the reason. They can trigger IBS symptoms, which may explain why you have more flare-ups at different points of your menstrual cycle and during menopause hormonal fluctuations.

Cells in your gut have receptors that let these hormones latch on to them. This suggests that your digestive system is designed to sense and react to them. Here are the main ways they affect IBS:

Digestion: They control the smooth muscle in your intestines, which dictates how quickly food travels through your system. In one study, animals took longer to empty their intestines when they received a low dose of the hormones than when they got a higher one. This may explain why low levels of sex hormones can lead to constipation.

Pain level: These hormones affect how much stomach cramps bother you. A dip lowers your pain threshold, in part because oestrogen boosts the production of serotonin, a feel-good chemical in your brain. A jump in oestrogen can reduce some of the ouch factor, so your bellyaches or cramps don’t hurt as much.

Inflammation: Sex hormones can raise levels of inflammation throughout your body. That makes your IBS symptoms worse and bioidentical progesterone also has the function of helping reduce inflammation in the body.

Most research has linked oestrogen and progesterone with IBS. But scientists have also found that male sex hormones, like testosterone, may protect against the condition. This may be partly why men are less likely to get the disorder.

Peri/Menopause and IBS

IBS worsens as hormone levels fall at the start of this cycle of life. But it’s unclear how this affects IBS as in some women it improves after menopause, when these hormonal changes stop.

On the other hand, more than a third of menopausal women in one recent study reported IBS-type symptoms, like wind and heartburn.

 Symptoms of IBS

IBS is diagnosed by recurrent abdominal pain for at least 6 months, combined with weekly pain for 3 months as well as some combination of pain relieved by bowel movements and changes in frequency or form of bowel movements.

Your doctor may refer you to a gastroenterologist, a specialist in digestive diseases, who can help you identify triggers and discuss ways to control your symptoms.

If you are not sure these are the most common symptoms:

1. Pain and cramping The most common symptom of IBS is lower abdominal pain that is less severe after a bowel movement. Dietary modifications, stress-reducing therapies and certain medications can help reduce pain.

2. Diarrhoea This is one of the three main types of the disorder. It affects roughly one-third of patients with IBS. Frequent, loose stools are common and are a symptom of the diarrhoea-predominant type. Stools may also contain mucus.

3. Constipation Although it seems counterintuitive, IBS can cause constipation as well as diarrhoea and is the most common type, affecting nearly 50% of people with IBS.

Constipation is very common. However, abdominal pain that improves after a bowel movement and a sensation of incomplete bowel movements after passing stool are signs of IBS.

4. Alternating constipation and diarrhoea Mixed or alternating constipation and diarrhea affects about 20% of patients with IBS. Throughout each phase, they continue to experience pain relieved by bowel movements.

5. Changes in bowel movements Slow-moving stool in the intestine often becomes dehydrated as the intestine absorbs water.

IBS changes the time stool remains in your intestines and this changes the amount of water in stool, giving it a range from loose and watery to hard and dry.

6. Gas and bloating Altered digestion in IBS leads to more gas production in the gut. This can cause bloating, which is uncomfortable.

In a study of 337 IBS patients, 83% reported bloating and cramping. Both symptoms were more common in women and in constipation-predominant IBS or mixed types of IBS

Following a low-FODMAPs diet can help reduce bloating. FODMAP stands for Fermentable Oligosaccharides, Disaccharides, Monosaccharides, and Polyols, which are short chain carbohydrates and sugar alcohols that are poorly absorbed by the body, resulting in abdominal pain and bloating.

7. Food Intolerance Up to 70% of individuals with IBS report that particular foods trigger symptoms but why these foods trigger symptoms is unclear. These food intolerances are not allergies, and trigger foods don’t cause measurable differences in digestion.

While trigger foods are different for everyone, some common ones include gas-producing foods, such as FODMAPs, (see above point 6) as well as lactose, gluten and stimulants such as caffeine.

8. Fatigue and difficulty sleeping Over half of people with IBS report fatigue and IBS is also related to insomnia. Interestingly, poor sleep predicts more severe gastrointestinal symptoms the following day.

9. Anxiety and depression IBS is linked to anxiety and depression, as well but it’s unclear whether IBS symptoms are an expression of mental stress or whether the stress of living with IBS makes people more prone to psychological difficulties.

Whichever comes first, anxiety and digestive IBS symptoms reinforce one another in a vicious cycle. More positively, another study found that anxiety reduction therapy reduced stress and IBS symptoms (36Trusted Source).

How to help yourself

Diet, stress, poor sleep and changes in gut bacteria may all trigger symptoms. However, triggers are different for each person, making it difficult to name specific foods or stressors that everyone with the disorder should avoid .

Lifestyle changes, such as a low-FODMAPs diet, stress relief, exercise, drinking plenty of water and over-the-counter laxatives can also help. Interestingly, a low-FODMAP diet is one of the most promising lifestyle changes for alleviating symptoms.

On a low-FODMAP diet these are what to avoid:

Fructose: Fruits, honey, high-fructose corn syrup, agave
Lactose: Dairy
Fructans: Wheat, onions, garlic
Galactans: Legumes, such as beans, lentils, and soybeans
Polyols: Sugar alcohols and fruits that have pits or seeds, such as apples, avocados, cherries, figs, peaches, or plums

Avoiding FODMAPs doesn’t help everyone. But in a study published in the journal Gastroenterology, about 3 out of 4 people with IBS had their symptoms ease right away after starting a low-FODMAP diet and felt the most relief after 7 days or more on the plan.

Identifying other trigger foods can be difficult, as these are different for each person. Keeping a diary of meals and ingredients can help identify triggers

Additionally, avoiding digestive stimulants, such as caffeine, alcohol and sugary beverages, can reduce symptoms in some people

If your symptoms don’t respond to lifestyle changes or over-the-counter treatments, there are several medications proven to help in difficult cases.