Brain Health

Brain Fog May Be Treated by Healing the Gut

BY Health 1+1 TIMEJuly 8, 2022 PRINT

“Brain fog” is a frequently mentioned symptom in recent years.When people describe themselves as having brain fog, they often mention poor memory, difficulty concentrating and slow thinking. In addition to COVID-19 related brain fog, intestinal problems can also be one of the factors that trigger brain fog. What are the ways to improve brain fog from the intestines and brain?

According to Dr. Chih Hao Lin, neurologist and director of the Brain Stroke Center at Lin Shin Hospital, brain fog is cognitive dysfunction. Memory, judgment, behavior, emotions, languages, spatial sense, and other cognitive functions are all part of the brain’s operations.

Brain fog is not a disease, but a symptom. Although it manifests in the brain, it can also be caused by poor intestinal health.

The intestines are also known as the “second brain,” as there are many nerves in the intestines, which have a lot of neural connections with the brain through the neural network. Dr. Lin pointed out that it is indeed clinically observable that many patients with degenerative brain diseases, for example, experience gastrointestinal symptoms, such as poor digestion and constipation, five to 10 years before the onset of the brain diseases.

Another example is irritable bowel syndrome (IBS), which plagues many people nowadays, with patients being prone to brain fog, anxiety, and other non-intestinal symptoms.

IBS is a chronic condition that causes abdominal pain, diarrhea, or constipation, when the patient feels stressed or nervous. Currently, it is widely believed that emotions and stress are the factors that trigger IBS and make its conditions even worse.

Now there is a new view that intestinal problems can also affect the brain in turn. Jay Pasricha, director of the Johns Hopkins Center for Neurogastroenterology, pointed out that people with IBS, as well as people with functional bowel problems, such as constipation, diarrhea, bloating, and abdominal pain, have a higher than normal rate of depression and anxiety, because the nerves in the bowel may send signals to the central nervous system, which can trigger mood changes.

Stress, anxiety, and depression also tend to produce inflammatory substances that can lead to brain fog.

In addition to IBS, there are also some gastrointestinal disorders that can cause brain fog, including celiac disease, leaky gut syndrome, inflammatory bowel disease, and small intestine bacterial overgrowth syndrome.

Another cause of brain fog is related to excessive production of D-lactic acid by intestinal bacteria.

In a small-scale study conducted in 2018, 30 patients with brain fog and bloating were observed to be taking probiotics. Among them, 63.3 percent had small intestinal bacterial overgrowth syndrome, and 77 percent had D-lactic acid toxicity.

The study concluded that the benefits of probiotics should be felt in the colon or rectum.

However, too much probiotic supplementation can cause brain fog due to various reasons, such as diabetes, small intestine resection, or poor peristalsis, which can cause carbohydrates to be broken down by probiotics in the small intestine and produce more D-lactic acid.

Besides causing intestinal problems, the bacteria Helicobacter pylori, which can survive in the stomach and cause gastric cancer, may also bring about brain fog.

Dr. Lin explained that Helicobacter pylori can affect the absorption of nutrients, causing vitamin B12 deficiency and resulting in brain fog symptoms, because vitamin B12 is very important for the stability of the nerves. Vitamin B12 deficiency is also common in people with poor gastrointestinal tract absorption, people with unbalanced diets, vegetarians, and patients who frequently take stomach medications.

In addition to gastrointestinal symptoms, other factors, such as viral infections, poor sleep quality and hormonal changes in females (during the menstrual period, and during and after pregnancy) can also cause brain fog symptoms.

3 Ways to Make Your Brain and Intestines Healthy and Clear up Brain Fog

It is common to find online articles talking about which foods can eliminate brain fog. However, Dr. Lin believes that the problem of brain fog cannot be improved by eating certain foods alone, especially because the relationship between the intestines and the brain is very complex. Instead, he recommended a wholesome diet, exercise, and healthy lifestyle habits.

  • Mediterranean diet

Whether it is to improve brain fog, prevent dementia, or protect the brain, a balanced diet is necessary. Dr. Lin recommended the Mediterranean diet, which includes vegetables and fruits, nuts, legumes, whole grains, fish, dairy products, and olive oil. Many studies have shown that the Mediterranean diet can improve thinking, memory, and brain health.

A recent study has discovered that eating a Mediterranean diet leads to changes in intestinal microbiota, which are associated with improved cognitive functions, memory, immunity, and bone strength.

Dr. Lin cautioned that red wine is part of the Mediterranean diet, but he didn’t recommend drinking alcohol, whether it is red wine , beer, or other alcoholic beverages. In particular, people over 50 years old should not drink alcohol. Alcohol is not very helpful to our health. And it affects the absorption of some nutrients and also reduces sleep quality.

A study published by the University of Oxford in 2017 shows that the hippocampus in the brain atrophies with increasing amounts of alcohol consumption. Even in people with light or moderate alcohol consumption, their hippocampal atrophies were more serious than those who did not drink. The hippocampus plays a major role in memory and spatial orientation navigation.

The Mediterranean diet also includes cereals and milk, but they should not be consumed in excess, depending on the individual’s condition. People with poor digestion should avoid excessive intake of carbohydrates, and people with lactose intolerance should minimize milk consumption to reduce the occurrence of intestinal problems.

Fermented milk products, such as yogurt and yogurt drinks, are less likely to cause lactose intolerance, and they also contain probiotics. Probiotic intake from food is considered safe, due to its amount.

Taking antibiotics or other factors can alter the intestinal microbiome, so additional probiotic supplements can be taken. However, although probiotic supplements can be helpful for the intestinal tract, excessive or indiscriminate use of probiotic products is not recommended for the general public. If you experience flatulence after taking probiotics, you should consult your physician.

  • Aerobic exercise combined with weight training

Dr. Lin pointed out that many people’s unhealthy intestinal tract is related to the lack of exercise, especially because the lack of muscle strength will cause the intestinal peristalsis to slow down, causing the proliferation of bacteria. Therefore, it is recommended to strengthen the muscles through weight training.

Exercise can also improve mood and sleep quality, reduce stress and anxiety, and directly and indirectly help memory and thinking. An article from Harvard Medical School pointed out that in comparison with people who do not exercise, people who exercise have a larger prefrontal cortex and medial temporal cortex, which are the parts of the brain that control thinking and memory.

  • Positive and healthy lifestyle habits

Healing the gut can heal the brain, and the reverse is also true. “I believe that having a healthy brain is good for intestinal health,” said Dr. Lin. What should we do? In addition to the Mediterranean diet and exercise, it is also important to ensure good sleep quality, he advised.

According to Dr. Lin, there are two important mechanisms in sleep: one is to strengthen memory; and the other is to remove toxins and waste produced by the brain during the day. If you often stay up late or have insomnia, it is impossible to remove these waste products, resulting in obstacles impeding the brain’s operations.

Sleep also helps every system in the body function properly, including the immune system, the heart, the brain, and even the digestive system. Poor sleep quality can damage intestinal health in many ways.

At the same time, it is important to learn to shift the source of stress, maintain a positive mindset and relax at the right time to avoid brain dysregulation and brain fog.

For instance, participating in social activities, learning new things, or playing games not only help relieve stress, but also help keep the brain sharp and maintain a good memory.

Epoch Health articles are for informational purposes and are not a substitute for individualized medical advice. Please consult a trusted professional for personal medical advice, diagnoses, and treatment. Have a question? Email us at

Health 1+1
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