As we live our day-to-day lives, we may be completely unaware of the trillions of micro-organisms that reside in the gut and the important role they play in bodily functions. This active and ever-changing collection make up the system known as the gut microbiome.

The gut microbiome is a complex composition of organisms which play a pivotal role in numerous bodily functions, such as food digestion, managing metabolic processes, efficiency in passing waste, influencing mental health and even supporting immune response. With an estimated 1,000 different types of bacteria inhabiting the digestive system, the composition of the gut microbiome is as unique to a person as a fingerprint. Although studies have revealed there is strong evidence to suggest that there is an inherited element when it comes to the gut microbiome1. External environmental influences, such as the changing of the seasons or changes to the daily routine, can play a significant role in altering its composition. Naturally, through the colder months, behaviours and activities alter – which inevitably influences the gut bacteria too. So, how do seasonal shifts change or influence the composition of the gut microbiome? Do we need to give good gut bacteria a little extra support over colder months?


Generally speaking, food consumed in the winter, compared to summer months, tends to be higher in fat and sugars. Annual holiday festivities, along with increased alcohol intake, all have an impact on the health of the gut microbiome. So, it comes as no surprise that many of us pile on the odd pound or two during winter! Although it's commonly considered to be an emotive reaction to the shorter days and colder weather, Exeter University2, has suggested that the subconscious urge to over-eat is in part due to an evolutional process which makes the body want to store fat during the winter months – so to a certain extent, it may be instinctive. The body requires a diverse range of nutrients to keep it functioning at its very best and bacteria are at the heart of our wellbeing. Our good gut microbes help to support a wide range of the body's functions. For example, a narrower diet over cold months, typically featuring fewer fresh fruit and vegetables, may mean that the good bacteria are not as well-supported as during summer months. During the colder months, opting for foods which are rich in prebiotic fibre, such as fresh fruits, vegetables, grains and nuts, can support the gut microbiome resilience and stability by nourishing the good bacteria.

Fruit & Vegetables


The chilly weather conditions of winter lessen the determination to exercise and can easily drive us to grab a blanket instead. Although relaxation and a positive mindset do have an impact on the health of the gut (click here to learn more about the gut-brain axis), regular and effective aerobic workouts have proven to positively impact the gut microbiome. Studies have shown that productive daily exercise enhances diversity and encourages the proliferation of good bacteria in the gut3. Of course, our good gut bugs come with additional benefits to physical and mental health – so we should always be aiming to support and nourish them wherever possible. Continued exercise, whether indoor or outdoor, during the winter months, significantly aids in maintaining a healthy gut microbiome. So, whether that's dusting off an exercise bike or catching a sunny afternoon for a run, exercising regularly over colder months supports the gut microbiome.

Immune System

The body's immune system fights off pathogens, viruses and toxic substances on a daily basis, keeping us at peak performance. What may surprise many is that 70% of the immune systems is held within the gut4, so the gut microbiome plays a critical role in supporting the immune function. In fact, the gut has even been called the immune system’s ‘control tower’!

The key to understanding this important relationship is knowing that the digestive system operates on its own self-held nervous system, which communicates with the brain. We know this relationship as the ‘gut-brain axis’. Our gut bacteria help to keep pathogens from the food and drink we consume at bay through strengthening the intestinal wall, but the gut can also send signals to the brain that alter or change how our body functions. This includes how our immune cells identify threats and respond. The onset of winter sees a rise in coughs, colds and the flu sweep through the population. Keeping fit, rested and eating healthily can help prevent infections and maintain a healthy and diverse gut microbiome. However, with this increased likelihood of illness, there is the growing concern of excessive antibiotic use. Antibiotics may be prescribed by a healthcare professional or GP due to a bacterial infection - but they do not get rid of a virus. A course of antibiotics can lose some of the good bacteria in the gut, as well as the bad. It can take time for the good gut bacteria to recover; up to a year in some circumstances5. Naturally, we may wish to give the good gut bacteria an extra helping hand by encouraging nourishment and growth of these helpful microbes in the gut microbiome.


Where do prebiotics fit in?

Prebiotics supplements, like Bimuno®, can aid the gut the microbiome through the changing of the seasons. Adding Bimuno to your daily routine helps to support your gut microbiome by stimulating the growth of bifidobacteria, a type of good bacteria. For further information on prebiotics and the role they play in supporting the gut microbiome, visit the Bimuno learning resources. The Bimuno website breaks down the fundamentals of gut health, and you can discover how the trillions of microbes in the gut play a part in physical and mental health. Discover more here.

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