There Are More Bacteria in Your Body Than Human Cells

Did you know that your body contains more bacterial cells than human cells? That’s over 30 trillion! But before you rush to the nearest shower, hear me out—not all bacteria are bad. In fact, most of them are tiny allies working behind the scenes to keep you healthy. They help with everything from boosting your immune system to digesting food and even influencing your mood. Pretty wild, right?

In this blog post, we’ll dive into the fascinating world of our microbiome, uncover why these microscopic helpers are so important, and share some easy ways to keep them thriving.

Why Do We Have Bacteria in Our Body?

From Birth Onwards

The bacteria in our bodies aren’t just random passengers—they’ve been with us since day one. As soon as we’re born, our microbiome begins to develop. If a baby is born through natural birth, their first dose of beneficial bacteria comes from their mother’s birth canal, helping kickstart their immune system. Babies born via C-section get their first bacteria from skin contact and their surroundings. Then, during breastfeeding, more good bacteria and prebiotics (which help good bacteria grow) are introduced.

Childhood to Adulthood

Our microbiome isn’t a one-size-fits-all situation. As we grow and experience life—playing outside, meeting new people, eating different foods—our microbiome evolves with us. Our environment, lifestyle, and diet all play a role in shaping it.

By the time we reach adulthood, our microbiome becomes more stable, meaning the types and amounts of bacteria in our body stay relatively consistent. This stability is thanks to everyday exposure to different bacteria through food, pets, dirt, and even interactions with other people.

Why Are These Bacteria Important?

These tiny organisms are far more powerful than they look. They support our health in ways you might not even realise.

1. They Keep Your Immune System Strong

Your microbiome plays a huge role in training your immune system to recognise and fight off harmful invaders. Here’s how:

• Communicating with immune cells in the gut, where 70% of your immune system is located.
• Producing short-chain fatty acids (SCFAs) that help regulate immune responses.
• Strengthening the gut barrier, which prevents harmful microbes from sneaking into your bloodstream.

Good bacteria also compete with bad bacteria for space and resources, making it harder for harmful bugs to take over.

2. They Affect Your Mood and Mental Health

Ever had a “gut feeling” about something? That’s not just a saying—your gut and brain are directly connected through what’s called the gut-brain axis. The bacteria in your gut can influence how you feel, think, and even how well you handle stress.

In fact, certain gut bacteria produce serotonin and dopamine, which are the chemicals responsible for happiness and motivation. An imbalance in gut bacteria has even been linked to anxiety, depression, and neurodegenerative diseases. So, taking care of your gut could literally boost your mood!

3. They Help You Digest Food and Absorb Nutrients

Gut bacteria are like little chefs, breaking down food and helping your body absorb key nutrients. Some fibres and complex carbohydrates are impossible for our digestive system to break down alone, so our gut bacteria step in to help.

They also produce SCFAs, which:

• Strengthen the gut lining
• Support immune function
• Help regulate appetite

Plus, your microbiome helps produce essential vitamins like vitamin K (needed for blood clotting) and B vitamins(important for energy production).

What Happens If Your Microbiome Falls Out of Balance?

An imbalance of good and bad bacteria—known as dysbiosis—can lead to all sorts of issues, including:

• Digestive problems (IBS, bloating, diarrhea)
• Autoimmune diseases
• Mental health struggles (anxiety, depression)
• Obesity and metabolic disorders

What causes this imbalance? Here are some of the biggest culprits:

1. Poor Diet

• Diets high in processed foods (low in fiber, high in sugar and artificial sweeteners) can feed harmful bacteria.
• Excess red meat and fatty meats can promote inflammation-causing bacteria.

2. Antibiotics and Medications

• Frequent antibiotic use wipes out both harmful and beneficial bacteria, throwing your microbiome off balance.
• Other medications like antacids, NSAIDs (ibuprofen), and steroids can also disrupt gut bacteria.

3. Lack of Sleep and High Stress Levels

• Chronic stress releases hormones that reduce beneficial bacteria.
• Poor sleep quality messes with your body’s natural rhythms, which affects your microbiome’s stability.

4. Infections and Illness

• Bacterial or viral infections can wipe out good bacteria.
• Some infections can cause harmful bacteria, like C. difficile, to overgrow.

How to Keep Your Microbiome Healthy

Taking care of your gut bacteria doesn’t have to be complicated. A few simple habits can make a huge difference:

1. Eat More Fiber – Think of fiber as food for your microbiome. Load up on fiber-rich foods like avocados, raspberries, broccoli, oats, and lentils. Swap out processed snacks for whole, natural foods.
2. Add Fermented Foods to Your Diet – Foods like yogurt, kimchi, sauerkraut, kefir, and miso are packed with probiotics (good bacteria) that help maintain gut balance.
3. Be Mindful with Antibiotics – Only take antibiotics when absolutely necessary and prescribed by a doctor. If you do need them, consider taking a probiotic afterward to replenish your good bacteria.
4. Stay Hydrated – Water supports digestion, keeps your gut’s protective mucus layer intact, and promotes the growth of beneficial bacteria.
5. Prioritise Sleep and Manage Stress – Poor sleep and stress can disrupt your microbiome, so aim for 7–9 hours of quality sleep per night and find stress-relieving activities like meditation, exercise, or journaling.

Some take-home points

Your microbiome is a key player in your overall health, influencing digestion, immunity, and even your mood. The good news? By making a few simple changes—eating fibre-rich and fermented foods, staying hydrated, managing stress, and getting quality sleep—you can support your gut bacteria and, in turn, your well-being.

So, next time you think about bacteria, remember: they’re not just germs—they’re tiny superheroes working to keep you healthy!