Long COVID: How It Can Disrupt Gut Health

Long COVID can pose significant challenges for individuals who have recovered from the initial COVID-19 infection. This condition is characterized by long-term after-effects such as muscle pain, fatigue, breathing difficulties, and more. In addition to these symptoms, research has shown that long COVID can affect the gastrointestinal (GI) tract, leading to various digestive issues. Changes in gut-brain signaling may result in gastrointestinal disorders. Studies indicate that individuals who have had COVID-19 are at a higher risk of developing GI disorders within a year after their initial infection.

Dyspepsia (Indigestion or upset stomach): Dyspepsia, or functional dyspepsia is a gastrointestinal disorder of the brain gut axis. Stress, dietary changes and anxiety during the illness and through recovery can also contribute to dyspepsia. The symptoms can be stomach pain, bloating, and feeling overly-full. Some may even experience heartburn, acid reflux, and excessive burping. The actual cause of functional dyspepsia is not known, but its effects can linger. According to a study published on GI disorders after covid recovery, 39.5% of patients had new onset GI disorders. 58 of them had functional dyspepsia. 

Irritable Bowel Syndrome (IBS): IBS, also known as irritable bowel syndrome can also develop as a result of having long covid. It can present with symptoms such as abdominal pain, changes in bowel habits, and bloating. After having covid, it can disrupt the gut-brain axis which is responsible for regulating GI function. The disruption of the gut-brain axis and inflammation from covid can trigger IBS symptoms in some individuals. According to research, increased incidence of IBS can be related mainly to deterioration of mental health, especially when having covid. 

Constipation: Research shows that constipation is associated with long covid after the initial infection. In a study of 147 patients without prior GI symptoms, 6.8% of the patients developed new onset of constipation after having covid. Constipation seems to be the most common manifestation in patients with long covid. Covid can cause damage and inflammation to the lining mucosa of the intestine by infecting gastrointestinal cells, this can contribute to constipation and other GI issues. 

Nausea: Nausea is also common with long covid, which can show the prolonged effects of covid on the nervous and GI systems. In a meta-analysis of 43 studies which had 18,246 patients, 6.3% were experiencing nausea and vomiting. For some, the anxiety and stress linked to having covid and dealing with long covid symptoms can intensify the feeling of nausea. There is an established connection between the chronic GI symptoms and mental health symptoms such as anxiety and depression. 

Abdominal Pain: Abdominal pain when dealing with long covid can vary on how it feels, from mild abdominal cramps to persistent and intense abdominal pain. This pain can be due to the disruptions to the gut microbiome when having covid, it can cause notable changes to the gut flora. Chronic inflammation from covid can also cause chronic abdominal pain after the initial infection, this is because the inflammation disrupts the normal bacteria in the gut. This can lead to stimulation of some of the GI systems nerves. 

Bloating: Bloating, another common and uncomfortable issue with long covid can stem from disruptions to the gastrointestinal system. Inflammation from covid can cause the stomach to feel swollen and full. According to research, those who had covid were 54% more likely to experience GI symptoms such as bloating, abdominal pain and more.

Acid Reflux: Acid reflux, also known as gastroesophageal reflux disease (GERD), is also a symptom of long covid. Covid is associated with a severe inflammatory response, which can contribute to symptoms such as acid reflux. A study done on covid-19 and GERD states that GI symptoms are known to occur with 29% of patients six months after recovering from covid. Among the 29% of patients, acid reflux symptoms were reported in 27% of them. New onset GERD symptoms from covid can unfortunately last over a year or can persist long-term. 

Weight loss: Along with other GI symptoms, weight loss is also common in those that suffer from long covid. Weight loss can happen due to muscle loss and fat loss. This usually occurs due to malnutrition, lack of appetite, lack of physical activity,  lingering GI symptoms, and prolonged loss of smell and taste. Significant weight loss can persist after the initial covid infection, short-term and long-term. According to 8% of those that survived covid and are suffering from long covid had experienced persistent weight loss. 

Gut Microbiota Imbalance: Significant changes to the gut microbiota are common in those with long covid. This can be as a result of inflammation from the covid virus. The inflammation can cause ulcerations in the stomach, duodenum, and oesophagus, which in turn also causes GI symptoms as well. Changes in gut bacteria were related to an increase in blood markers of tissue damage and inflammatory cytokines. The changes in gut bacteria can persist even after recovering from covid. According to research, the covid infection reduces the diversity of bacteria in the gut.