WHAT ARE BIFIDOBACTERIA?
by Jelena Vulevic on Dec 03, 2021
Your gut is home to a complex ecosystem of microbes, called the gut microbiota, that play a critical role in your overall health (read more here).
Among the various commensal gut microbes, is a group of beneficial bacteria called Bifidobacteria that are often used as probiotics. They help us with digestion, fight against harmful bacteria, production of vitamins (eg K and B vitamins) and other important molecules (eg lactic and acetic acids). Above all, these bacteria positively influence your immune system, and are an important component of it, from your birth to the end of your life. For these reasons they are a keystone genus of the healthy gut and their reduced number and/or malfunction is strongly related to a number of different diseases as well as ageing.
What are Bifidobacteria?
Bifidobacterium spp. (species), are bacteria commonly found in your gastrointestinal (GI) tract, other mammals, some birds and social insects such as honey bees. They have a distinctive shape amongst microbes that resembles letter Y (called bifid) and so their name comes from that.
Henry Tissier was the first person who isolated bifidobacteria from the stools of breast-fed infants in 1899. Today, there are more than 70 different species of bifidobacteria, that possess a large number of genes encoding enzymes involved in the degradation of fibres and non-digestible glycans, reflecting their significant role in processing the diverse range of carbohydrates consumed through your diet.
Bifidobacteria live inside your GI tract, from birth to old age. They colonise the new-born gut within the first days and weeks after birth, and they represent the most abundant bacterial family, covering over 80% of the infant total gut microbiota.
How Bifidobacteria get inside the infant gut and what happens then?
Bifidobacteria are transmitted vertically from the mother’s vagina, GI tract or breast milk onto the infant. Hence, their number and diversity in the infant gut are strongly dependent on environmental factors such as:
mode of delivery (natural or C-section delivery)
type of feeding (breast or formula milk)
duration of gestation (full-term or premature birth)
In this context, naturally delivered and breast-fed infants generally possess a higher number and diversity of bifidobacterial populations when compared to the gut microbiota of those infants born by C-section and fed with formula milk.
As the infant begins to consume solid foods, overall bacterial diversity increases as a result of an expanding nutritional environment. The abundance of bifidobacteria decreases quite rapidly to 30–40% at that stage, and it continues to fall gradually during childhood and adolescence.
As we reach adulthood, bifidobacterial populations stabilise between 2 and 14% (depending on lifestyle choices) with a further decline recorded as we enter the older phase of life. Their decline strongly correlates with a decrease in immune function, aka immunosenescence.
Overall, bifidobacterial levels across your life course align with key stages in immune maturation, and are associated with improved well-being and immune function. It is interesting that a reduced number of bifidobacteria in infants, is highly correlated with chronic diseases, including asthma and obesity later in life. Concurrently, higher number of bifidobacteria in later stages of life, are correlated with health and longevity.
Consequently, many studies have focused on the role of bifidobacteria in immunity, both in health and various diseases.
How can bifidobacteria affect your immune function?
Data from studies indicate that bifidobacteria have beneficial effects both in treating and preventing immune-linked diseases. What’s really interesting is that these effects are not in your gut only, but they extend systemically throughout your body and can therefore affect the conditions in organs that are distant to the gut. They do this via their interaction with the immune system which is largely (around 70% of it) situated in your gut and involved in pretty much everything that goes on in your body.
Bifidobacteria have a complex role, having both pro- and anti-inflammatory effects, promoting anti-pathogen immune responses, and modulating immunity in the context of auto-immune or immune-mediated diseases, in a species-dependant manner. Species dependent manner means that not all bifidobacteria (eg probiotics) can do all, or even any of those things. Studies have shown that bifidobacterial modulation of specific parts of your immune system and their outputs, are based and dependent on the presence of certain molecules that they produce and use to interact or communicate with your immune system. These molecules include pili (hair-like structures present on their surface), cell-wall polysaccharides (types of sugars that they produce inside them) and exopolysaccharides (EPS) (types of sugars that they produce and excrete).
Figure adopted from here
What are health benefits of bifidobacteria as probiotic supplements?
Various studies have reported improvements in intestinal regularity and relief of constipation with ingestion of bifidobacteria as probiotic supplements. In this regard, strains belonging to Bifidobacterium animalis and Bifidobacterium lactis have the most evidence so far.
Bifidobacteria have also been extensively used to treat various GI disorders. More specifically treatment of infectious diarrhoea, or inhibition of rotavirus infection, in infants and children has been reported with administration of species belonging to Bifidobacterium infantis and Bifidobacterium breve . Oral treatment with a probiotic formula containing Bifidobacterium lactis and Streptococcus thermophiles was reported to reduce antibiotic-associated diarrhoea.
Lower incidences of necrotizing enterocolitis in preterm neonates have been reported following administration of Bifidobacterium breve . In association with breast-feeding, B. breve was also shown to significantly reduce the incidence of necrotising enterocolitis in neonates born before 34 weeks gestation and those born at a gestation age of less than 28 weeks.
Inflammatory Bowel Disease (IBD)
Reduction in the symptoms, and maintained remission, of Ulcerative Colitis following treatment with multi-strain preparations that included bifidobacteria, was firstly reported over 20 years ago. Still the mechanisms of action aren’t fully identified, and the scientific evidence is not conclusive with the respect of relief in IBD. It seems that effects are better with multi-species preparations (eg VSL#3) or in combination with prebiotics (food for probiotics) than with bifidobacteria alone.
Several animal model studies have reported results that suggest inclusion of bifidobacteria in combination with prebiotics may reduce the occurrence of carcinogen-induced cancerous cells in mice. The best studied examples include Bifidobacterium animalis, Bifidobacterium longum and Bifidobacterium breve. However, convincing evidence from humans is lacking.
There are a number of other conditions, including Irritable Bowel Syndrome (IBS), allergies (skin and respiratory tract), infections related to cancer therapies, liver problems, metabolism issues and mental health issues, where probiotic bifidobacterial preparations have been reported to have beneficial effects. However, evidence is not consistent, and more work is needed.
How can you increase bifidobacteria in your gut?
Include foods high in fibre:
Fruits such as apples, berries, pears, melon and oranges
Vegetables such as carrots, sweetcorn and broccoli
Beans, peas and pulses
Potato with skin
Nuts and seeds
Wholegrain breakfast cereals, wholewheat pasta, wholegrain bread and oats, barley and rye
Include foods high in prebiotics:
Root vegetables (chicory, Jerusalem artichokes, konjac, burdock, yacon and jicama)
Allium vegetables (garlic, leeks and onions)
Fruits (bananas and apples)
Whole grains (wheat, barley and flaxseeds)
Others (asparagus, dandelion greens, cocoa and seaweed)
Note that cooking destroys prebiotic content, so for best results these should be eaten raw.
Include foods rich in polyphenols:
Seasonings (cloves, star anise and dried peppermint)
Drinks (red wine, black and green tea)
Cocoa and dark chocolate
Fruits (berries, plums, apples, black currents, cherries and pomegranate)
Nuts (hazelnuts, pecans and almonds)
Vegetables (artichokes, endives, red onion and spinach)
Soybeans and its products (tofu, tempeh, flour or yogurt)
Choose vaginal birth if possible and breastfeed your baby if possible
With the exception of vaginal birth and breastfeeding, all of the above will not selectively increase bifidobacteria only. They will, however, contribute to their growth and better balance between the good and not so good bacteria, as well as improve an overall diversity of your gut microbiota which is strongly linked to better overall health.
Fermented foods (eg kimchi, kefir, yogurt, sauerkraut) will also improve overall diversity and balance of your gut microbiota. These types of foods contain live microbes but not bifidobacteria. The exception are yogurts made by Danone (eg Activia).
For selective increase in your own gut bifidobacteria, you should try prebiotic supplements that contain either oligofructose (fructooligosaccharides) or trans-galactooligosaccharides (these are only found naturally in human breast milk).
Probiotic supplements that contain bifidobacteria can also increase their numbers in your gut but there is no guarantee that they will be effective or remain in your gut. If you are thinking of incorporating probiotics into your lifestyle than you should check if they have clinical evidence behind them because not all bifidobacteria (probiotics) are effective for everything or will even have any benefit. The good examples to start your research are strains belonging to Bifidobacterium longum, Bifidobacterium lactis, Bifidobacterium animalis and Bifidobacterium breve.
How is The Y Collection connected with bifidobacteria?
The Y in the centre of our logo represents the shape of bifidobacteria from which Y Skin, and other products that we are currently working on, are derived from. We have concentrated on extracting the benefit from bifidobacteria and bringing it back into use in a form of a food grade, natural and free of additives supplements.
Our supplements incorporate signalling molecules from bifidobacteria that they use to benefit your immune system when you are young, by blocking the entry of inflammatory stimuli. Inflammation is the number one reason for ageing and so the result of taking our supplements is slower ageing effect inside your body. With Y Skin this manifest in healthy and glowing skin, as skin is the mirror of your health. Our approach combines gut and immune system function, with skin care (the gut-skin axis) for a far more holistic approach, in helping to reduce the ageing effects of a modern lifestyle, such as pollution, stress and diet.