Interest in digestive health has increased dramatically in recent years – hardly surprising given that almost half (43%) of UK adults have some sort of digestive problem.
Tummy pain or discomfort is the commonest digestive issue, with 2 in 3 digestive sufferers complaining of it; diarrhoea and bloating both affect more than ½ of people with digestive issues and wind and flatulence almost half. Living with poor digestive health can have a huge impact on quality of life – more than 1 in 10 consultations in general practice centres on gut problems.
What is the digestive system?
- Lots of people believe that the digestive system stretches from ‘tum to bum’. In fact, ‘gum to bum’ is more accurate.
- The process of digestion starts in your mouth, where food is broken down by your teeth and saliva starts digesting your food by producing enzymes which break down carbohydrates.
- Once swallowed, food travels down your oesophagus (gullet), a muscular tube which contracts regularly in waves (peristalsis) to propel food from your throat to your stomach.
- The inside of your stomach is highly acidic, thanks to acid produced by specialised parietal cells. This helps break down food into a mulch while enzymes called pepsin and lipase break down proteins and fat respectively.
- On to the small intestine, where your pancreas, liver and cells in the small intestine wall provide digestive juices rich in enzymes and bile that break down food further. Most nutrients from food are absorbed here.
- The final big part is the large intestine, where water and salts are absorbed, making your watery food residue more solid.
- Finally, it reaches the rectum and the anus, where your poo – made up largely of water, undigested food, fibre, mucus, bile, bacteria and cells from the gut lining - is passed out.
What do we mean by digestive health?
The term digestive health covers a variety of areas including:
- Effective digestion of food within the gut
- Effective absorption of the products of digestion into the bloodstream from the gut
- Not having any gastrointestinal (GI) symptoms
- A stable and healthy balance of gut microbiome (the trillions of bacteria, fungi and viruses that live naturally in the gut)
- Feeling well in yourself.
Why is digestive health important?
Digestive health and your gut symptoms
One of the commonest GI issues is irritable bowel syndrome or IBS. This is a ‘functional bowel disorder’ – there’s no abnormality to find with any one part of the gut, but the various parts don’t work smoothly together. It can lead to a host of GI symptoms including tummy pain (often colicky and relieved by opening your bowels); bloating and wind; and constipation, diarrhoea or bouts of both.
Other conditions can also GI symptoms including indigestion, heartburn, bloating, tummy pain, wind, feeling or being sick, diarrhoea, constipation and more.
All of these symptoms are distressing in their own right, but poor digestive health can also have a profound impact on your mood and general wellbeing. Feeling generally unwell can of course affect your mood.
Gut microbiome at the heart
Your gut microbiome plays a pivotal role in your overall, as well as your digestive health. An imbalance between healthy and unhealthy bacteria within the microbiome is called dysbiosis. And dysbiosis has been strongly linked to everything from digestive conditions such as IBS and inflammatory bowel disease to depression and other mental health disorders.
Your gut is packed with nerve cells, which control the release of digestive fluids, gut blood supply for food absorption and much more. This 'enteric nervous system has the same type of nerve cells (neurons) – more than 100 million of them - and neurotransmitters as those found in your central nervous system. Both immune and nerve cells are in constant intimate contact with your gut microbiome. So it’s hardly surprising that getting the balance of your gut microbiome right can affect your digestive health.
Digestive health beyond the gut
Gut health goes way beyond your gut, especially where the gut microbiome is concerned. Dysbiosis – where the balance of bacteria in your gut is skewed towards unhealthy bacteria – seems to be a culprit in diseases affecting both your body and your brain.
- Heart disease. Poor digestive health has been linked to a range of risk factors for heart attack and stroke, including high blood pressure, atherosclerosis (furring up of the arteries) and heart failure.
- Obesity. There’s clear evidence of a link between dysbiosis and obesity. Your microbiome can affect the stability of energy consumption by your body, how fat is deposited and levels of inflammation in the body, among others.
- Type 2 diabetes. Rates of type 2 diabetes are rising rapidly along with our waistlines. Your gut microbiome is closely linked to your body’s ability to process the hormone insulin – and insulin resistance is the main driver of type 2 diabetes.
- Mental health. there has also been increasing interest in recent years in the gut brain axis – the complex interplay of two-way messages between the gut and the brain.
How can I improve my digestive health?
- Move it. Regular physical activity can help keep your bowels working normally – as well, of course, as the well-known benefits for your heart and lungs.
- Get your zzzs. Lack of sleep can affect your gut microbiome. Prioritising healthy regular sleep patterns can improve your digestive health.
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Eat mindfully. Eating slowly without distractions and chewing your food thoroughly can help reduce wind, bloating and pain.
- Water, water everywhere. Water is the ideal fluid to keep your levels of hydration up. Being dehydrated contributes to constipation and tummy pain.
- Finger on the pulse. Pulses, beans and lentils are great food for the healthy bacteria in your gut. Cut down on meat and substitute pulses in your stews or casseroles – or add them to soups, salads and traybakes.
- Eat a rainbow. Vegetables and fruits all contain different chemicals, nutrients and types of fibre. Each of these supports and encourages different microbes. While standard advice has focused on 5 portions of fruit and veg a day, there’s now every bit as much focus on including a wide range. Aim for 30 different fruit, vegetables, legumes, nuts and seeds a week.
- Feed your gut with fibre. As well as improving the diversity of the gut microbiome, a high fibre diet has been linked to lower levels of heart disease, some cancers and obesity. Most of us eat only 18g a day of fibre, far less than the recommended 30g.
- Unprocessed is best. People who eat a lot of ultra-processed foods have a far lower range of healthy bacteria in the gut. Cooking from scratch means fewer additives, less processing and more of the good stuff. Fruits, vegetables, wholegrains, unflavoured dairy, eggs, seafood, poultry and lean red meat are all unprocessed.
- Healthy growth promotion. Prebiotic foods contain types of fibre, such as inulin, which promote the growth of healthy rather than unhelpful bacteria in your gut. Good food sources include garlic, onion, leeks, Jerusalem artichokes, apples, beans and peas, whole grains.
- Poly-plants. Antioxidant polyphenols can improve the quality of your gut microbiome. They’re found in herbs and spices, colourful fruit and veg, berries, nuts, seeds, olives, coffee, green tea and cocoa.
- Fermented foods. Probiotics are sources of good bacteria, which help to tip the balance in favour of a healthy microbiome. Sauerkraut, live yoghurt, kefir, kombucha, miso, tempeh, kimchi and sourdough bread are all good sources.
- Supplementary evidence. Probiotic supplements come in all shapes and sizes. They aim to provide high quantities of healthy bacteria – mostly specific species of Lactobacillus, Enterococcus and Bifidobacterium – which will colonise the gut and crowd out unhealthy bacteria.
More Ask the Experts
What can I do to look after my gut microbiome
What's the relationship between stress and IBS?
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