How to improve microflora balance in the gut?
Kelly Lo, HK BioTek Intern
The microorganisms that live in your intestines are referred to as the "gut microbiome". In the digestive tract, a person possesses between 300 and 500 distinct types of bacteria. Gut health is the balance of bacteria in the digestive tract. Studies on gut bacteria proved that having a diverse population of good bacteria in your gut can improve your immune system, alleviate depression symptoms, aid in weight loss, and provide a variety of other benefits . Apart from taking probiotic supplements, there are also other effective ways to boost your gut’s beneficial bacteria.
Consume a wide variety of foods
In your intestines, there are hundreds of different bacteria species. Each species has a unique role in your health and requires a different set of nutrients to thrive. In general, a diversified microbiota is thought to be beneficial to one's health. This is because the greater the number of bacteria species you have, the more health benefits they bring.
However, the modern diet, especially the Western diet, is higher in fats, simple carbohydrates, and lower in fiber, compared to the traditional diet . This reduces the diversity of beneficial microbes in the gut and leading to decreasing gut health in the modern generations. A varied microbiome can be achieved by eating a variety of foods [3, 4].
Eat prebiotic foods and fermented foods
Probiotics can be found naturally in fermented foods. Regularly eating foods including fermented vegetables, kimchi, miso, tempeh, etc. may help to enhance gut health. For example, Lactobacilli can aid in the digestion of food, the absorption of nutrients, and the defense against disease-causing microbes . Lactobacilli tend to be more abundant in the intestines of those who consume a lot of yogurts. These individuals also have lower levels of Enterobacteriaceae, a bacteria related to inflammation and a variety of chronic disorders .
Also, yogurt consumption has been demonstrated in a number of trials to alter gut bacteria and reduce lactose intolerance symptoms in both children and adults [7, 8]. In persons with irritable bowel syndrome, various yogurt products may help reduce the number of bacteria that cause sickness. Yogurt also improved the function and composition of the microbiota, according to a study . It's worth noting, however, that many yogurts, particularly flavored yogurts, contain a lot of sugar. As a result, plain and natural yogurt is the best yogurt to ingest. This type of yogurt is manufactured solely of milk and bacterium mixes.
Eat more fruits, vegetables, and high-fiber foods
The finest sources of nutrients for a healthy microbiome are fruits and vegetables. Many fruits, vegetables, and high-fiber foods are prebiotics. They are foods that can facilitate the growth of beneficial bacteria in your gut, such as Bifidobacteria which may help alleviate diarrhea and constipation .
Your body can't process foods that are high in fiber. Yet, some bacteria in your gut can digest fiber. This promotes their growth. Beans and legumes also have a lot of fiber in them. Here are some high-fiber foods that are beneficial to your gut bacteria: raspberries, artichokes, peas, lentils, broccoli, beans, whole grain, etc.
Reduce the amount of sugar and sweeteners
Gut dysbiosis, or an imbalance of gut bacteria, can be caused by eating a lot of sugar or artificial sweeteners. The conventional Western diet is high in sugar and fat, it is shown to have a deleterious impact on the gut flora. As a result, the brain and behavior may be affected .
According to an animal study, the artificial sweetener aspartame raises the number of bacterial strains . These bacterial strains are associated with metabolic syndrome, which is a group of disorders that raises diabetes and heart disease risks. Artificial sweeteners have also been shown to have a deleterious impact on blood glucose levels in humans due to their effects on gut flora. This means that artificial sweeteners, despite not being sugars, may raise blood sugar levels .
Manage stress, have enough sleep, and regular exercise
Stress management is associated with your gut health. Psychological stressors have been shown in animal experiments to alter the bacteria in the intestines, even if the stress is just temporary . A range of stressors can have a deleterious impact on gut health in humans, which include environmental stress, such as excessive heat, cold, or noise psychological stress, sleep deprivation, circadian rhythm disruption, etc. 
Meditation, deep breathing exercises, and progressive muscle relaxation are some stress management approaches. Stress can also be reduced by exercising regularly, sleeping well, and eating a healthy diet. Exercising on a regular basis is beneficial to heart health and weight loss or weight maintenance. It has also been suggested by research that it may help manage obesity by improving gut health . A 2014 study discovered that athletes' intestinal flora was more diverse than that of non-athletes . Adults should participate in at least 150 minutes of moderate-intensity physical activity each week, as well as muscle-strengthening activities on two or more days per week, according to the Physical Activity Guidelines for Americans.
Furthermore, a good night's sleep can help with mood, cognitive, and intestinal health. According to an animal study in 2014, irregular sleep habits and disrupted sleep negatively affected the gut flora, thereby increasing the risk of inflammatory disorders . By going to bed and waking up at the same time every day, you can develop healthy sleeping patterns. Adults should sleep for at least 7 hours each night.
While certain bacteria are hazardous to our health, many others are beneficial and even required for a healthy body to function properly. Maintaining the appropriate balance of bacteria in the gut is critical for physical and mental health, immunity, and other factors.
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