This essay will explore the role of gut flora in the digestion process, specifically the role of gut flora in digestion in the elderly population. The gut microbiota has the largest number of bacteria compared to any other part of the body. Gut flora develops in humans one to two years after birth, by this time the intestinal epithelium and the intestinal mucosal barrier that is secreted would have developed together in a way which supports and is tolerant to the gut flora, also providing a barrier to pathogenic organisms. In our gut, trillions of bacteria along with tiny organisms called flora live there. Three main types of flora can be found in the gut: beneficial flora, opportunistic flora and transitional flora. Beneficial flora aids in the digestion and absorption of food and produces chemicals that protect us from viruses, bad bacteria and fungi. Opportunistic flora, ‘bad bacteria’, when not managed can cause diseases. Transitional flora is the bacteria that is found in bacteria food and drink. If the gut is healthy, these bacteria will not cause any harm when passing through. Age, health and diet affect the amount and type of flora in each part of the gut. Ageing affects our body both externally and internally. When going through the ageing process, bodily functions slow down, including the efficiency of the digestive tract. This essay will explore factors that affect gut health during old age and what can be done to improve gut flora to aid in efficient digestion during old age.
As the ageing process progresses, there is a decline in microbiome diversity. As a person reaches the age of 60, their gut microbiome would have undergone changes, these being the bacteria inside the gut would have become less diverse, and beneficial microbes, like Lactobacillus and Bifidobacterium, would have become less. However, there will be an increase in enterobacteria populations, opportunistic bacteria. Gut dysbiosis is linked to an increased risk of several chronic diseases. Negative alterations that occur in the gut microbiome have been linked to age-related diseases. The most common cause of cognitive impairment in the elderly is Alzheimer’s disease. Research has shown probiotic supplements are beneficial in the improvement of cognitive function and memory in people suffering from the disease, which suggests the microbiome’s role in the disease. During old age, it is likely an individual’s mobility will become reduced compared to when they were younger, also elderly people tend to have a less diverse diet, generally consuming foods low in fibre. These factors can have an impact on the diversity of an individual’s gut bacteria.
During the ageing process, our immune system isn’t as efficient as it once was, and this affects an individual’s gut health. As we age the number and efficiency of immune cells decline. This is why the elderly are more at risk of serious complications when contracting common infections, such as a cold. The weakened immune system doesn’t function as efficiently as it once did, therefore it may allow immune cells to attack healthy tissues. The main function of the gut is to extract nutrients whilst keeping out infection and toxins. To do so, the gut lining is covered by a layer of mucous, and its cells let out antimicrobial compounds that deter bacteria from entering the body this way. Studies in primates have shown how the integrity and mobility of the gut decline with age, regardless of diet. This is likely to happen to the human gut also. Having a lower diversity of gut bacteria can affect the gut lining, as bacteria play an important role in modulating the immune system and deterring pathogens that could want to cross into the body.
During the ageing process, an individual’s joints will age, muscles get weaker, bones will lose density, and movement, in general, becomes increasingly difficult. Our teeth also grow old, meaning the majority of the elderly population will use dentures. These factors will influence what food is consumed. These changes to an individual’s diet during old age can harm the diversity of beneficial bacteria in the microbiome. A study by Gosh et al. (2020) has shown that individuals whose diet is mainly made up of food rich in fibre (similar to the Mediterranean diet) have greater microbiome diversity, and therefore generally better health. However, it was also discovered that individuals who consume a diet with a lot of processed and red meat, high-fat dairy products, sweetened drinks and potatoes fail to maintain a healthy gut environment.
A factor of ageing is reduced physical ability. A study by Monda et al., 2017 has shown that exercise increases the diversity in the gut microbiome, however, exercise can be harder for elderly people who are more likely to have hospital stays or live in care homes.
Another factor of the ageing process which affects our gut health is medication and illnesses. As we grow old, we are more likely to experience illnesses. Resulting in more medication being consumed, which can affect the gut microbiome health. To treat infections and other medical problems, prescription drugs may be prescribed, these drugs may interact with the gut microbiome. Elderly people will likely be prescribed drugs such as painkillers and antidepressants to manage blood lipids, and diabetes can also change the relative abundance of different gut bacteria. Older people are more likely to be prescribed such drugs because many of these health conditions manifest with age.
To conclude, an individual’s gut flora is affected by the ageing process. Through factors discussed such as a weakened immune system, a change in diet, reduced physical activity, taking medication and illnesses. To help in improving gut flora and therefore having a more efficient digestive system, things that would be beneficial for an elderly person to do would be firstly maintaining a healthy diet. It is vital to consume foods high in fibre such as vegetables, fruits and whole grains. It is also beneficial to be as active as it is possible and perhaps to consider taking a prebiotic. Probiotics are live bacteria and yeasts that are good for the body, especially for the digestive system. For example, when beneficial bacteria in the body are lost, through taking antibiotics, probiotics help in replacing the beneficial bacteria in the gut. It is important to have good gut health to aid in efficient digestion.