Bloating: A Comprehensive Guide to Tackle Bloating and Why Gut Microbiome is the Key

Bloating is a common form of digestive discomfort. It can make you feel uncomfortable and even fit to burst after a meal. But what causes it? And what does it mean for your gut and overall health? 

In this article, we look at what bloating is, what causes it and the role of your gut microbiome.

What is bloating?

Bloating is really common with 10 to 25% of healthy people reporting they feel regularly bloated[i]. Most of us will have experienced bloating at some point in our lifetime, especially if we’ve been a little overindulgent.

But what exactly is bloating?

Bloating is a form of digestive discomfort which causes your stomach to feel full and uncomfortable, often because there is a lot of gas in your gut[ii]. There are many different causes of bloating, and in many cases, there are things you can do to ease the discomfort or even prevent it.

Fact:You may hear bloating being referred to as distension: the medical definition for swelling and becoming larger because of pressure within.

Symptoms of bloating

Bloating affects the stomach and the common symptoms include:

• Discomfort or pain
• Rumbling noises
• Excess wind
• Feeling full or your tummy feeling larger than usual 

What causes bloating?

There are several reasons why bloating occurs. Usually, it’s lifestyle related and nothing to worry about. In most cases, it’ll go away on its own or with a little encouragement through exercise, massage or changing your eating habits.

However, if bloating doesn’t go away and is a regular occurrence for you, you should make an appointment with your doctor to find out what’s going on.

The main cause of bloating is too much gas in the gut which can have some pretty unpleasant side effects, like farting, burping or looking a little larger than usual. If gas is the issue, it could be caused by the food or drink you consume. For example, eating lots of vegetables, legumes or regularly drinking fizzy drinks may be the culprits.

Most people experience bloating at the end of the day or after they have eaten a meal. So, eating too much in one go may cause your tummy to go a little wild and feel bloated. Or perhaps you eat with your mouth open; this causes you to gulp in lots of air when you eat. If that sounds like you, try to get into the habit of eating slowly and with your mouth closed to stop you swallowing too much air and ruining your food.

These common causes can be rectified by limiting or choosing what you eat carefully or eating with your mouth closed. But bloating can also be a common sign of other issues.

Carbonated drinks and artificial sweeteners

Fizzy drinks contain carbon dioxide, it’s what gives them their distinctive ‘fizz’. But this addition of carbon dioxide can cause your tummy to swell and become full of gas. Plus, many fizzy drinks also contain artificial sweeteners which can be difficult for your body to digest and may cause bloating[iii].

Look out for drinks that contain sorbitol which cannot be digested or fructose, a naturally occurring sugar which many people have difficulty processing and may cause your tummy to feel uncomfortable.

Constipation

Constipation occurs when your poo stays in your colon for too long; it can mean you do not go to the toilet regularly or are unable to pass stools at all. It can cause hard, lumpy stools that may be unusually large or small[iv].

Constipation isn’t usually serious but it can be unpleasant and uncomfortable, causing a bloated belly. Finding ways to relieve constipation will ease bloating, such as eating more fibre, drinking plenty of water, or taking a laxative.

SIBO

Small Intestinal Bacterial Overgrowth or SIBO is a condition caused by an abnormal overgrowth of bacteria in the small intestine, especially the types which aren’t usually resident there. It’s often associated with chronic diarrhoea and malabsorption which may result in unintentional weight loss, bone disorders like osteoporosis, and nutritional deficiencies[v]. People who experience SIBO report symptoms, such as bloating as well as irritable bowel syndrome (IBS).

Irritable bowel syndrome

Irritable bowel syndrome (IBS) is a common condition that affects the digestive system and studies show that over 61% of patients report bloating symptoms[vi]. The exact cause of IBS is unknown and the triggers will vary from person to person, but it has been associated with:

• Fast food transit through the GI tract
• Sensitive gut nerves
• Stress
• Specific foods
• Family history[vii]

Coeliac disease

Coeliac disease is an autoimmune condition caused by your body’s immune system mistaking gluten as a threat to the body. As a result, your immune system attacks the specific substances in gluten it thinks are harmful, resulting in some unpleasant symptoms[viii].

One of those symptoms is bloating because the absorption of carbs reduces which causes a greater production of gas[ix]. Coeliac disease is a major cause of malabsorption, so when the small intestine is unable to absorb nutrients from food it can result in stomach pain, diarrhoea, and bloating.

Menstruation

That’s right for many women, bloating is a common early sign that they are going to have their period. It often occurs one to two weeks before, and some women also experience swelling in other areas of their body such as their arms or legs and some report having puffy faces, making them look tired.

It’s thought that premenstrual bloating is caused by water retention but why it occurs is still a bit of a conundrum. Experts believe bloating could be related to the hormonal changes that occur during the menstrual cycle or genetics.

Bloating and the gut microbiome

There’s also another hefty contributor to the bloat as well; your gut microbiome. The special thing about the ecosystem residing in your gut is it could be the cause of your bloating but it could also hold the secrets to the cure.

Gut microbiome, dysbiosis, and bloating

The human gut microbiome consists of trillion of tiny microbes, contributing to an ecosystem that can promote and maintain Your health, when it is in the right balance. The bacteria in your gut are responsible for some of the major functions associated with the digestive system, like breaking down fibre and transforming it into useful metabolites.

A bi-product of these activities is gas. Humans can produce and excrete a pretty phenomenal amount of hydrogen, methane and carbon dioxide, ranging from 214 to 705 mL per day. Or in rather more crude terms, that’s about 14 to 18[x]!

An increase in the amount of gas can be a good indicator that the digestive process isn’t working as it should, and can cause some nasty symptoms including flatulence, bloating, and abdominal discomfort.

A well-balanced gut microbiome is key to health and helps to keep both the digestive and immune systems in check. However, out of balance and it can cause several digestive symptoms.

Fact:If your gut microbiome is out of kilter or off balance it’s called dysbiosis. Dysbiosis occurs when the abundance of good bacteria is reduced, and pathogenic bacteria grow and become abundant, resulting in a lack of diversity[xi].

An imbalance of beneficial and pathogenic bacteria has been implicated in digestive problems, including the occurrence of bloating. Research has shown that some bacterial groups are prone to producing more gas than others and can exacerbate bloating symptoms, such as Enterobacteriaceaeand Clostridia[xii].

On the flip side, if your bloating is being caused by an imbalanced gut, then modifying your microbiome through diet and lifestyle choices may help to relieve the symptoms by restoring balance and allowing the beneficial microbes to flourish.

How to treat bloating

To treat bloating, it’s likely you need to address the lifestyle factors contributing to its onset. In doing so, you’ll also be helping to support the health of your gut and the rest of your digestive system.

Here are some of our top tips to help you relieve the symptoms of bloating:

1. Eat smaller portions.Although it can be tempting at times, especially if you’re hungry, eating larger portions can actually contribute to bloating. Large plates can increase the gaseous production in your gut and slow down the transit time through your GI tract. So, cut down on your portion sizes and try to limit snacking throughout the day.
2. Chew your food. It may seem obvious or you may be totally unaware that you’re not chewing properly, but eating too fast or not giving your food a good chew can promote bloating. That’s because you could be a victim of aerophagia or swallowing lots of air. Chewing properly stimulates the production of digestive enzymes which kickstarts the digestive process.
3. Get an intolerance or allergy test. Sometimes bloating is caused by an allergy or intolerance to a specific food. If you suspect this may be the case, it’s a good idea to get a test to rule this out. Keeping a food diary to record everything you eat and drink as well as how you felt afterwards, can also help to identify any potential triggers.
4. Lower your sugar and salt intake. Refined white sugars and carbs are good sources of sustenance for the pathogens in your gut. So, the less you feed them the better, swap for unrefined sugar or wholegrain or wholemeal sources of carbs. Salt also increases water retention in your gut which can lead to bloating and constipation[xiii], try to keep below the maximum daily amount of 6g (for adults).
5. Lower stress.Stress is a regular part of life for many of us but it can also play havoc with other areas of our health, including our digestion. Stress has a negative effect on the overall composition of your gut microbiome which can slow the rate of digestion, leaving you feeling bloated. If you can, try to limit your exposure to stressful situations or use mechanisms like meditation, mindfulness, exercise or social interaction to help you cope.
6. Taking part in light exercise on a regular basis can help rid excess gas from your bowels. A recent study found that light exercise such as a 10-to-15-minute walk after a meal can relieve the symptoms of bloating. Exercise is a cheap and effective way to get relief from a full belly[xiv].

Using the gut microbiome to relieve bloating

There are certain microbiome targeted things you could try to help relieve and prevent bloating. Of course, by helping to get your microbiota in balance, you’ll also reap the full health benefits this cool little ecosystem has to offer.

Try probiotics

The research into the use of probiotics for bloating has yielded mixed results. Some studies show probiotics can relieve the discomfort while others have found it can make it worse. But don’t let that put you off, when you first start taking probiotics or introducing good bacteria into your diet you may experience some side effects. That’s because the bacteria are increasing in numbers and are a little more active. These effects usually subside within a few weeks.

A review published in 2018 found that probiotics could relieve IBS symptoms including bloating[xv]. Some well-researched probiotic strains for bloating include:

• Lactobacillus acidophilusNCFM[xvi]
• Bifidobacterium lactisHN019[xvii]
• Lactobacillus plantarumLp299v
• Bifidobacterium lactisBi-07
• Bifidobacterium infantis35624

In a study by Ringel-Kulka et al. (2011), it was found that two probiotic strains, L. acidophilusNCFM and B. lactisBi-07, improved bloating symptoms in people with functional bowel disorders.

Experiment with fermented foods

Fermented foods naturally contain probiotic bacteria and can be a good place to start introducing these strains into your diet if you’re not sure about probiotic supplements.

Perhaps the most familiar probiotic food is live yoghurt. It can be a good source of health-promoting bacteria but can also be full of sugar, so always check the label.

Other delicious, fermented foods include:

• Kimchi
• Sauerkraut
• Kombucha
• Kefir
• Miso
• Tempeh

Reduce your fibre intake

If you already eat lots of fibrous foods and you’re feeling bloated, you may be consuming too much. Fibre is an important part of your diet, there’s no two ways about it but gradually build up your intake so you don’t overwhelm your microbial pals.

Remember, certain fibre sources are also associated with bloating like legumes, beans, and some wholegrains. So, monitor your intake and cut down if you need to.

Add right fibre to your diet

For most of us who follow the Western Diet though, it’s more likely that we’re not eating enough fibre and that’s why we feel bloated. The diet typically consists of high fat and an extortionate refined sugar level and little fibre – it’s not great for your health and your gut microbiota isn’t keen either.

After a high fat meal, it’s not uncommon to experience digestive discomfort like bloating, feeling full, and nausea[xviii]. Therefore, it can be useful to cut down on the fatty meals and graduallyincrease your fibre intake. We emphasise a gradual increase because too much too soon can be too drastic and actually do more harm than good.

That’s because the beneficial microbes in your gut are responsible for breaking down the fibre you eat and transforming it into substances your body can use, as well as provide themselves with nourishment. So, a harsh increase will boost their activity and their gas production, causing you to feel bloated.

If you have increased your fibre intake and are experiencing some unpleasant symptoms, you’ll be glad to hear that they usually subside after a short transition period of approximately two weeks.

Try a low-FODMAP diet

FODMAP stands for fermentable oligo-, di-, monosaccharides and polyols which are specific carbohydrates naturally present in many foods. FODMAPs can be a problem for people with dysbiosis because they stimulate the growth and activity of colonic bacteria.

A low FODMAP diet is often prescribed to people with a specific type of IBS that is associated with SIBO. FODMAPs are dietary fibres that cause discomfort when they are fermented by your gut microbes.

A low FODMAP diet works by excluding different plant foods (fruit, vegetables, wholegrains, legumes etc) and then slowly reintroducing them to identify any triggers of digestive symptoms.

FODMAP examples

Fact:You should only follow a low-FODMAP diet under the supervision of a medical professional.

HMO prebiotics 

Human milk oligosaccharides (HMOs) are the sugar component present in breast milk and belong to a group of carbohydrate molecules called glycans. They are also a prebiotic and help to nourish the beneficial microbes in the gut.

There have been numerous research studies demonstrating the benefits of HMOs for both infants and adults, particularly for composition of the gut microbiota, immune system, and the intestinal epithelial barrier[xix].

But some studies show that HMOs may also help alleviate some common digestive symptoms. A prospective, open-label, single-arm, clinical trial found that taking a 5g mix of two HMOs, 2’-fucosyllactose (2’-FL) and Lacto-N-neotetraose (LNnT), improved the severity of IBS and associated symptoms including bloating[xx].

There are several proposed reasons why HMOs can have this positive effect on the quality of life of IBS sufferers. The first mechanism of action is the increased abundance of Bifidobacteriaby these HMOs. An increase in Bifidobacteria is associated with positive health outcomes in children and adults.

People with IBS often have a low abundance of Bifidobacteria which may affect the number of SCFAs the microbiota produces, particularly acetate. Acetate helps to maintain the pH of the colon but also nourishes the bacteria responsible for producing butyrate, the major energy source for colonocytes.

Plus, Bifidobacteriahas also previously been shown to have a positive impact on the severity of IBS symptoms. By increasing the abundance of Bifidobacteriain the gut, HMOs help to restore and maintain balance, which may be why they can have such a good impact on digestive discomfort.

Layer Origin’s HMOs do not contain any human milk and instead are fermented from lactose in cow’s milk. But they are biologically identical to human milk derived HMOs and produce the same benefits. Check out our range of HMO products.

Summary

Bloating is a common digestive symptom with many people experiencing it regularly. It’s often caused by excess gas production in your gut leading to symptoms such as flatulence, feeling full, and discomfort.

Commonly, bloating is caused by lifestyle factors, including specific foods, fizzy drinks, swallowing air when you eat, or not getting enough exercise. However, an imbalanced gut microbiome may also be to blame, so there may be some things you need to do to rid your gut of dysbiosis and help it on the mend.

HMOs have been shown to relieve symptoms of bloating in IBS patients and are a promising treatment. The third most abundant component in human breast milk, HMOs help to boost the abundance and activity of Bifidobacteria,promoting balance and good gut health.

Written by: Leanne Edermaniger, M.Sc. Leanne is a professional science writer who specializes in human health and enjoys writing about all things related to the gut microbiome. 

References

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