How A Diverse Gut Microbiome Can Show How You Age

Aging doesn't only show on the wrinkles in your face or gray hairs on your head, aging also happens in the microbiome in your gut.

It isn't the actual bacteria that is aging, but it is the diversity in the microbiome as a whole that changes as we age.

Our microbiome plays a large role in our digestion and how we live our life. It helps protect against other bacteria, regulates our immune system, and even produces vital vitamins for our body to use! Essentially, our microbiome is an aggregate of all the bacteria, viruses, or fungi that reside on or within our body and it changes over the course of our lifetime.

Early Years

Before we are born, we don't have any microbiome and we are just swimming from head to toe in our mother's womb. If it is an option, the best way to give your baby a headstart on making their own microbiome is a vaginal birth. This way, your baby will immediately come in contact with your vaginal commensal and probiotic bacteria, boosting their immune system development. Our little ones come out with a microbiome like a blank canvas and we can help them collect new colors for their microbiome in many ways through breastfeeding, avoiding early antibiotic exposure, and taking care of your maternal diet and microbiota.

The foundation of microbiota during infancy tends to fluctuate until your child is roughly three years old. At that point, the microbiome settles into a stable stage resembling an adult's microbiome. Around puberty there is another slight change. Many bacteria associated with testosterone and sex hormones take the spotlight on the gut microbiota stage. Particularly Adlercreutzia, Dorea, Clostridium and Parabacteroides are abundant in this time. While there are small changes in our microbiome throughout the years and it is always a homeostatic balancing act, our microbiome remains relatively stable throughout adulthood.

Later Years

As we finally get to the sunshine and glory of old age, our microbiota profile changes once again. We begin to experience dysbiosis, which is when the diversity of our microbiome declines. Where we used to have a microbial equilibrium between the beneficial and potentially pathogenic bacteria, a dysbiotic microbiome has a drastic imbalance. There are a few ways a dysbiotic microbiome could come about. There could be a loss of the beneficial organisms, growth in pathogenic organisms, or a reduction of overall microbial diversity. Even then, this phenomenon could be due to any number of reasons:

• A changed lifestyle or diet
• Less mobility
• A weakened immune system
• Reduced intestinal and overall functionality
• Recurrent infection, hospitalization, and/or use of medications

And many others. As we age, our microbiome begins to take a hit, having many possible effects on our daily living.

Maintaining a healthy balance in our gut microbiome proves to be vital in old age. As the more detrimental bacteria begin to build up in our gut, creating a dysbiotic microbiome, opportunistic bacteria begin to take to the stage. Opportunistic bacteria, which seek out opportunities when the immune system is weakened to cause disease, are seen to be more prevalent in elderly populations. Some common opportunistic bacteria that cause foodborne illness and infection of the large bowel are Enterobacteria, C. perfringens and C. difficile (C. diff). In old age, opportunistic bacteria are known to cause trouble, stimulating intestinal inflammation which can lead to various physiological or neurochemical impairments. As we try to minimize these effects, taking care of our intestinal microbiome is vital.

Not only is microbiota diversity important to maintain in old age, but metabolic capacity is also shown to be crucial in remaining healthy. A healthy metabolic capacity and oxygen consumption rate is important in order to be able to endure normal levels of physical activity and remain mobile. Reduced metabolic capacity related to the microbiome, such as lower short-chain fatty acid levels, may also be associated with irregular bowel movements, a smaller appetite, weight loss, cognitive decline, hypertension, and more. Staying active and healthy is important to maintaining your microbiome as you get older.

What can I do?

It is important to try to restore the homeostasis we enjoyed so much when we were younger.
Only recently, the distinct connection between our intestinal microbiome and aging was made. With this newfound foundation for how we can approach personal health in old age, we can do so much more! With simple dietary tweaks, we could help regulate our microbiota composition as our bodies age. Both probiotics and prebiotics have been thrown into the ring to help with aging.

Probiotics are living organisms, often Lactobacilli and Bifidobacteria strains, that can provide health benefits. Prebiotics on the other hand, are complex carbohydrates and stimulate the activity of bacteria. Working together, probiotics and prebiotics can help us manage homeostasis in our own intestinal microbiome and help by having an anti-inflammatory effect and regulating the immune system. With probiotics and prebiotics working to balance our microbiome, we can do anything!

While we haven't cracked the code to immortality quite yet, taking care of our gut and our body as a whole are a crucial first step.