Are Gut Bacteria and Weight Gain Connected?

If you have tried dieting and exercising but are not seeing results and have stomach issues or acne, your gut health might be telling you something. Gut bacteria and weight gain are closely related, and this article will discuss how that happens and how you can improve your life.

What Is Gut Health and What Does Gut Bacteria Do?

Gut health is the ability of your digestive system to function correctly. According to the International Scientific Association for Probiotics and Prebiotics, gut health is “a state of physical and mental well-being in the absence of gastrointestinal complaints that require the consultation of a doctor.” [1] 

This means that good gut health depends on having a good balance of bacteria and other microorganisms in your gut, which will help you digest food and take in nutrients. An imbalance of bacteria in the gut affects the body and mind and can negatively affect you long-term. 

Types of Bacteria in Your Gut

The gut microbiome is a diverse group of organisms, including bacteria, viruses, fungi, and more. Even if they sound harmful, these six main types of bacteria are needed in digestion and overall health. 

• Bacteroidetes

Bacteroidetes make up at least 30% of the bacteria in the human gut. They break down carbohydrates and produce short-chain fatty acids. They help digest food, provide nutrients, and help maintain a balanced immune system and healthy gut. While they usually benefit us, they can cause infections if they invade other body parts. [2]

• Firmicutes

Firmicutes are the second most common gut bacteria next to Bacteroidetes. They help break down fiber and produce butyrate, a compound that keeps the gut healthy and reduces inflammation. Most species of Firmicutes are harmless. Some types are, however, associated with certain infections that appear when other gut bacteria is reduced after antibiotic therapy, such as Clostridium difficile.[3]

• Proteobacteria

Proteobacteria can digest organic matter, carry out photosynthesis, or use materials such as ammonia and sulfur, making it versatile for different conditions. Even though they support digestion and nutrient balance, too many Proteobacteria can cause problems in the gut and are associated with inflammatory bowel disease and irritable bowel syndrome. [4]

• Actinobacteria 

According to research, food addiction is associated with reduced numbers of Actinobacteria in the gut. In animals, increased intake of prebiotics or probiotics has been believed to enhance digestion and general health, promising a potential treatment for both food addiction and weight gain. [5]

• Verrucomicrobia

Verrucomicrobia are typically present in large numbers among healthy people and possess anti-inflammatory properties that contribute to gut health. Recent studies suggest that Verrucomicrobia and A. muciniphila decrease inflammation and could be used to treat some gastrointestinal disorders. [6]

• Fusobacteria

Fusobacterium is normally found in the gut and becomes pathogenic when overgrown. Some strains are associated with colorectal carcinomas, such as Fusobacterium nucleatum which has been shown to induce inflammatory responses and suppress the immune system. It is linked to diseases like Crohn’s and ulcerative colitis, as well as oral health diseases like gingivitis. [7]

Gut Health and Metabolism

Gut bacteria have an impact on how the body absorbs food and stores fat. They change carbohydrates and fats into short-chain fatty acids that have an impact on hunger and energy use. These microbes break down polyphenols from fruits, vegetables, tea, and red wine. People connect polyphenols to many health benefits such as reducing inflammation and maintaining heart health. 

Gut bacteria also change fiber into SCFAs. These feed the cells that line the colon, make you feel less hungry, and affect your metabolism. The breakdown of bile acids makes them inactive so they can be used later to absorb fat. Proteins get broken down into amino acids, which are key to build and fix muscles.

 

Food, Gut Health, and Weight Control

You are what you eat. This means that what you put in your mouth will reflect on your gut. And your weight would significantly show how your gut feels.

Foods to Boost Gut Health

• Fruits:

Berries, apples, bananas, and oranges contain a lot of fiber and vitamins. They help grow the good bacteria, enhance digestion, and reduce inflammation. Try to aim for at least 2 servings a day. [9]

• Vegetables:

Leafy greens, broccoli, carrots, and bell peppers are rich in vitamins, minerals, and fiber. They aid digestion, keep the gut healthy, and promote bowel movements. For vegetables, 2 1/2 cups per day would be enough. [9]

• Beans and Legumes: 

These include lentils, chickpeas, black beans, and kidney beans. They are rich in protein and fiber and support good bacteria in your digestive system. Aim for at least 1-2 cups a day alongside other vegetables. [10]

• Whole Grains: 

Oats, quinoa, brown rice, and barley have fiber and nutrients. They’ll help your bowels go regular and give you energy. Though it sounds too much, experts recommend at least 6 cups a day.  [11]

• Fermented Foods (Probiotics):

Yogurt, kefir, sauerkraut, kimchi, and miso have live bacteria. They help maintain the balance of gut bacteria and facilitate better digestion. There isn’t an ideal serving size, but an intake of 1-2 portions per day is a great way to aim for that 10-20 billion CFU. [12]

• Prebiotic Foods: 

Garlic, onions, asparagus, bananas, and leeks contain prebiotics. They feed good bacteria, allowing them to multiply and thrive in the gut. Most prebiotics need at least 3-5 grams of it consumed daily to show its benefits. [13]

• Nuts and Seeds:

Almonds, walnuts, chia seeds, and flaxseeds are good sources of healthy fats and fiber. They aid digestion and keep your gut in shape. Experts recommend eating 30 grams at least a couple of times a week. [14]

• Water:

Drinking enough water is also important for digestion. It helps break down food, prevents constipation, and keeps everything running well. Men should drink at least 3,000 ml of water, and women should drink at least 2,200 ml of water, but this is not a definite number for everyone. [15]

Simple Habits to Support Gut Health 

• Regular Exercise

Do at least 30 minutes of physical activity 5 days a week to help you digest and feel better.  [16]

• Manage Stress

Manage stress with a few stress-relieving exercises, such as deep breathing, meditation, or yoga, to balance things in the gut.

• Stay Hydrated

Drink a lot of water to keep things moving in your gut and help digestion. 

• Eat a Balanced Diet

Eat more whole foods, including fruits, vegetables, whole grains, and lean proteins.

• Get Enough Sleep

Most adults need 7 to 9 hours of good quality sleep per night for overall health, including your gut. [17]

• Limit Processed Foods

Stay away from high-sugar and high-fat foods, as these will disrupt the good bacteria in your gut. [18]

Gut Health and Weight Gain

According to studies, Firmicutes and Bacteroidetes play a big role in how we use energy and manage weight. Germ-free mice (lack gut bacteria) can eat more without getting fat because their fat-burning process is not similar to those of normal mice. Fat mice naturally have a higher concentration of Firmicutes and lower Bacteroidetes. And when their bacteria is transferred to thin mice, the thin mice will get fatter. [19]

Administering antibiotics early in life also changes the gut bacteria, which may affect weight. In humans, having a lesser number of gut bacteria are linked to obesity and other medical issues. For example, infants with normal weight have more Bifidobacteria, while those who tend to become overweight have higher amounts of Staphylococcus aureus. This suggests that modifying gut bacteria could aid in controlling weight as well as preventing obesity. [20]

Can An Infection Cause Weight Gain?

Yes, infections can lead to weight gain. The most common infections associated with weight changes include small intestinal bacterial overgrowth (SIBO) and H. pylori.

Weight Gain With SIBO

SIBO is a term referring to the overpopulation of bacteria in the small intestine that interferes with the normal process of digestion. Its symptoms can vary from being mild to extremely severe and include chronic diarrhea, weight loss, and impaired nutrient absorption. [21]

Weight Gain With H. pylori

Helicobacter pylori, often simply referred to as H. pylori, is a bacteria known for causing stomach infections and is closely linked to being overweight. Scientific research has shown that H. pylori infection leads to obesity through disruption of hormones like leptin and ghrelin, which are known to regulate hunger and energy. Although eliminating H. pylori would temporarily increase hunger, it would also diminish the body’s sensitivity to leptin. [22]

Signs You Might Have Gut Health Issues

Your gut health is essential to your overall well-being, and problems in your gut can affect many areas of your life. The sooner you spot these warning signs, the sooner you can feel better.

Common Symptoms of Gut Health Issues 

• Digestive Problems: Gas, bloating, constipation, diarrhea, and heartburn.
• Changes in Bowel Movements: Irregular bowel movements or thin stools.
• Unexplained Weight Loss or Gain
• Fatigue: Feeling tired or difficulty sleeping.
• Mood Changes: Stress, low mood, or anxiety.
• Skin Problems: Acne, eczema, or psoriasis.
• Other Symptoms: Pain in the abdomen, decreased appetite, and anemia. [23]

Long-term Health Risks of Gut Issues

Gut issues, when left untreated, can worsen over time. Taking action and making small changes to improve your life is advised.

• Dysbiosis: 

Dysbiosis refers to a state in which there is an imbalance in the good bacteria over unhealthy gut bacteria. It is connected to a wide range of diseases, from IBD to obesity and diabetes. Here, the balance of the gut is destroyed, and you might develop chronic inflammation and digestive disorders over time. [24]

• Inflammatory Bowel Diseases (IBD):

Dysbiosis has been linked to ulcerative colitis and Crohn’s disease. IBD is chronic inflammation in the gastrointestinal tract, sometimes leading to severe abdominal pains, diarrhea, and other conditions. Abnormal immune reactions to gut bacteria can be among the factors influencing the development of IBD. [25]

• Increased Risk of Infections:

Altered gut microbiota makes the person more susceptible to infections, like Clostridium difficile and Salmonella infections. Beneficial bacteria reduce the pathogenic load on the gut. In their absence, there is an increase in pathogenic infection, leading to gastrointestinal infections. [25]

• Metabolic Disorders:

Gut bacteria play an important role in metabolism. Dysbiosis is linked with obesity and metabolic syndrome as the body fails to process sugar and fat efficiently and suffers from insulin resistance and more fat storage. [24]

• Gastrointestinal Symptoms:

Gut issues can lead to bloating, stomach aches, and diarrhea if left untreated. This is because some bacteria break down food by releasing gas and toxins that interfere with their intake of nutrients through regular digestion and gut irritation. [26]

• Increased Cancer Risk:

It would increase the chances of having colorectal cancer if dysbiosis or inflammation occurs in the gut. Changes in gut microbiota can develop conditions that promote the growth and development of a tumor. [27]

• Mental Health Issues:

The gut-brain axis shows that gastrointestinal health is connected to mental well-being. Researchers found that Dysbiosis has an association with anxiety and depression alongside various other psychiatric conditions, with the imbalance in the gut bacterial population influencing mood and even cognitive ability. [28]

• Autoimmune Diseases:

Autoimmune diseases may be due to the imbalance of gut bacteria and may end up causing the immune system to turn back against the healthy cells and lead to rheumatoid arthritis and multiple sclerosis. [29]

• Nutritional Deficiencies:

Gut problems can cause deficiencies due to poor absorption of essential nutrients. Dysbiosis can disrupt the process of digestion or absorption in ways that can create issues, such as anemia or vitamin deficiencies. [30]

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When to Talk to Your Healthcare Provider

If you notice any unusual change in your gut health, weight, or general condition, do not hesitate to consult your doctor for an appointment immediately. Take action before small issues turn into bigger headaches that would put you in pain for a much longer time. 

FAQ:

Does Gut Health Affect Weight?

Yes, gut health influences the body’s food processing and fat storage. An imbalance in gut bacteria causes weight gain and insulin resistance.

How Much Weight Can You Gain from Inflammation?

It is hard to estimate how much weight you can gain from inflammation, but it can range from 2kg to 30kg or even more.

Does Healing Your Gut Help You Lose Weight?

Yes, healing your gut will make you lose weight because this increases your metabolism, reduces inflammation, improves digestion, and balances the bacteria in the gut. 

What Causes Gut Bacteria Imbalance?

There are many reasons why dysbiosis (gut imbalance) occurs. It has much to do with personal factors, such as genetics, health issues, and lifestyle choices. Also, environmental factors matter, like high sugar and low fiber diet, antibiotics and other drugs, food additives, and hygiene. [31]

Which Gut Bacteria Cause Weight Gain?

Some gut bacteria are linked to weight gain, especially in obese people. They have more Firmicutes and fewer Bacteroidetes, which allows them to take up more energy and retain more fat. [32] Another type of bacteria called the segmented filamentous bacteria helps form immune cells and is called Th17 cells. In mice fed a diet high in fat and sugar, this decreases the amount of good bacteria, causing weight gain. [33]

Why Am I Gaining Weight On Probiotics?

Probiotics change your body’s response to hormones and inflammation, affecting your weight and eating habits. Some strains, like Lactobacillus acidophilus, Lactobacillus fermentum, and Lactobacillus ingluviei, can make you gain weight. But, Lactobacillus gasseri and Lactobacillus plantarum lead to weight loss. [34] 

What’s the link between leaky gut syndrome and weight gain?

Weight gain is often associated with leaky gut syndrome because it alters the balance of gut bacteria, which affects digestion and metabolism. Harmful substances can enter the bloodstream, causing inflammation and a change in how the body stores food and fat. [35]

How To Stop Weight Gain From Antibiotics?

To avoid weight gain from antibiotics, try to remain active and eat healthy food in smaller portions. You can also take probiotics to improve your gut health. If that is not working, discuss this with your doctor for a proper solution. 

Conclusion: 

Knowing more about how gut bacteria work inside our bodies can significantly help make our day-to-day easier. The right balance of them can help us digest food better to turn it to energy, improve the immune system, and regulate moods. The fact that gut bacteria and weight gain is connected can teach us how to take care of ourselves better and make smarter decisions.

Load up on fiber, eat foods rich in good bacteria, and get some exercise; then minimize stress, and your gut would be healthier. It is not easy, but each small step you take makes all the difference in the long run. Just keep at it and don’t give up!

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