The discussion around good versus bad bacteria is increasingly popular in health circles and the media, and it’s a bigger issue for us nowadays than it was for our ancestors. So, why now?
Well, most health experts agree that our modern lifestyle is somewhat to blame. And as a result, the microbes in our gastrointestinal tract, which is home to most of the bacteria in the body, is becoming depleted. It’s also leading to an imbalance between good and bad bacteria.
The good news is that our microbiome is constantly evolving and there are steps you can take each day to reverse the negative effects.
What does our microbiome do for us?
The community of bacteria and other microbes (yeasts and viruses) in our body is known as the microbiome, and this plays an essential role in keeping us healthy and happy in the following ways:
- Supply essential nutrients, such as vitamin K
- Encourage healthy digestion by breaking down complex particles, eg less bloating
- Ward off infection
- Assist in immune system function
- Promote mental health and brain function
What are the modern day habits contributing to poor gut health?
Not enough dietary fibre or prebiotics:
The main source of nutrition for gut bacteria is dietary fibre, yet most Western populations only consume half the recommended amount. This means fewer good bacteria in the gut. Gradually increasing dietary fibre intake, especially by eating prebiotics (a specific type of fibre) is one way to feed the good bacteria so they grow and thrive.
A healthy gut is a happy one: eating dietary fibres high in prebiotics may help
What can you do? Gradually increase dietary fibre and water intake over 7 days; NHMRC says women should aim for >25g dietary fibre and men >30g each day. Foods high in prebiotics (also good sources of dietary fibre) include: asparagus, beetroot, chicory, green peas, onion, garlic, legumes (eg chickpeas and lentils), some fruits (watermelon, nectarines), dried fruits (dates, figs), oats, barley, rye, cashews and pistachio nuts.
Not enough resistant starch:
Resistant starch is another type of fibre, known as fermentable fibre. Fermentable fibres play a special role in the gut because they enter the large bowel unaltered, and then go on to make short chain fatty acids, which ultimately protect the bowel wall.
What can you do? Good sources of resistant starch include wholegrains, cooked and cooled potato, firm bananas, and pulses and legumes.
Not moving as much as you should:
There’s no shortage of reasons to stay active, but what does physical activity have to do with the community of bacteria living in your gut? According to emerging research people who exercise not only have more bacteria (greater population), but also different types of bacteria (greater diversity) compared to those who are sedentary.
What can you do? The WHO recommends at least 150 minutes of moderate intensity aerobic activity per week, gradually increasing to 300 minutes per week. This means starting with 5 x 30 minute sessions of exercise. What’s considered moderate intensity? If you are lightly sweating, feeling warmer, experiencing slight swelling in hands and feet, but can still talk, you are probably exercising at moderate intensity.
Overusing antibiotics and household chemicals:
Antibiotic use is essential for treating or preventing bacterial infections. However, overusing antibiotics from childhood onwards can alter the shape of our microbiome and have lasting effects.
Over sanitising our spaces could lead to a more sensitive immune system
Additionally, compared to our ancestors, we now spend more time indoors in sanitised offices and homes and less time exposed to bacteria in the environment. Over several generations, this has led to a loss in biodiversity in our bodies.
What can you do? You may be tempted to abandon soap and life-saving antibiotics altogether. However, discontinuing good hygiene practices in our modern world is not the answer. Also, misusing or abandoning prescribed antibiotics can actually put you at greater risk of drug resistant diseases, so always complete your course. Instead, spend more time outdoors and take up a sport or gardening.
Don’t underestimate the benefits of eating a rich, diverse diet (a bit of everything!) and make this a life-long habit. Even if you start today, it’s never too late to reverse the effects of a depleted microbiome – research shows diet can change your gut bacteria in as little as one day. Also, cut out processed and refined sugar foods as this is killing your good bacteria.
Adding probiotics to your diet, either in capsule form, or in yoghurt and homemade fermented foods (eg kefir, sauerkraut, kimchee and kombucha), can also kick things along by promoting beneficial bacteria.