This glossary helps you understand key terms related to the gut microbiome, fermentation, and nutrition. Whether you're a parent, an athlete, or simply curious about your gut health, you'll find clear, evidence-based definitions here.
A
Lactic acid
A molecule produced during lactic fermentation, a natural process in which bacteria convert sugars into acid. In fermented foods like kefir or yogurt, lactic acid contributes to preservation, gives the characteristic tangy taste, and creates an acidic environment that influences microbial activity. In athletes, lactate is also produced by muscles during intense exercise.
Gut-brain axis
A bidirectional communication system between the digestive system and the brain, primarily via the vagus nerve. This axis explains why the state of your microbiome influences your mood, stress, and sleep — and vice versa. Research from INRAE and Inserm has shown that 95% of serotonin (the “feel-good” hormone) is produced in the gut. This is what’s referred to as the “gut feeling.”
→ Read also: The incredible power of the microbiome on stress and mental health
B
Gut biodiversity
The variety of microbial species present in the gut. Microbial diversity is an important characteristic of the gut microbiome and is studied for its relationship with various biological processes, including digestion and immune function. Dietary habits, including the consumption of fiber, fermented foods, and plant-based ingredients, are among the factors that can influence this diversity. Ultra-processed food consumption is also being studied for its potential effects on gut microbiome composition.
C
Plant-based calcium
Calcium sourced from non-animal foods: almonds, sesame seeds, kale, broccoli, figs, and calcium-rich mineral waters. Calcium is essential for bone growth in children and for maintaining bone density in adults and athletes. A minimiil shot provides plant-based calcium, contributing to daily recommended intake without relying on dairy.
CFU (Colony Forming Units)
A unit of measurement indicating the number of live, active bacteria in a probiotic product. The higher the CFU count, the more microorganisms are capable of colonizing the gut. A minimiil shot contains 10 billion CFU, a dosage considered effective by scientific literature (World Gastroenterology Organisation, 2017).
D
Dysbiosis
An imbalance in the gut microbiome characterized by reduced bacterial diversity or an overgrowth of potentially harmful bacteria. Dysbiosis can manifest as bloating, chronic fatigue, digestive issues, weakened immunity, or inflammation. Common causes include ultra-processed diets, chronic stress, antibiotic use, and lack of fiber. Restoring balance involves consuming probiotics and prebiotics.
E
Digestive enzymes
Proteins produced by the body (saliva, stomach, pancreas, intestines) that break down food into absorbable nutrients. The main ones are amylase (carbohydrates), lipase (fats), and protease (proteins). Fermented foods support digestion because fermentation pre-digests certain nutrients and naturally produces additional enzymes.
F
Fermentation
A natural biological process in which microorganisms (bacteria and yeasts) transform organic compounds, mainly sugars, into substances such as lactic acid, alcohol, or CO₂. In food, fermentation changes the composition of products, may introduce live microorganisms, and can influence the digestibility and bioavailability of certain nutrients. Kefir, yogurt, sauerkraut, kimchi, and kombucha are traditional fermented foods.
→ Read also: Fermented foods: what are they?
Prebiotic fibers
Non-digestible dietary fibers that serve as food for beneficial gut bacteria. The most well-known are inulin (chicory, agave, Jerusalem artichoke), fructo-oligosaccharides (FOS), and galacto-oligosaccharides (GOS). Unlike probiotics, which introduce live bacteria, prebiotics feed those already present in your gut. minimiil contains agave inulin, a recognized prebiotic.
Soluble vs. insoluble fiber
Soluble fiber (oats, legumes, fruits) dissolves in water and can form a gel, influencing digestion and interacting with the gut microbiome. Insoluble fiber (whole grains, vegetables, fruit skins) does not dissolve in water and contributes to stool bulk and intestinal transit. For adults, ANSES recommends a daily fiber intake of around 30 g, ideally from a variety of plant-based sources.
→ Read also: Soluble vs insoluble fiber: what’s the difference?
Gut flora
An outdated term for the gut microbiome. The word “flora” incorrectly suggested that gut microorganisms were plants. The modern scientific term is “microbiome,” which better reflects the diversity of organisms present: bacteria, archaea, fungi, viruses, and protozoa.
G
Gut health
A widely used term referring to the overall health of the digestive system, particularly the balance of the gut microbiome. Gut health goes beyond digestion: it influences immunity (70% of the immune system resides in the gut, according to the French Society of Immunology), energy, mood, sleep quality, and athletic recovery. It’s the philosophy at the core of minimiil: a daily ritual to nourish your gut.
I
Gut immunity
The gut houses a significant proportion of the body’s immune cells. The gut microbiome interacts with the intestinal barrier and plays a role in various biological processes, including immune responses and inflammation. The relationship between microbial diversity and immune function is an important area of scientific research, particularly in children, adults, and athletes exposed to physical stress.
Low-grade chronic inflammation
A persistent but subtle inflammatory state, often linked to microbiome imbalance (dysbiosis), ultra-processed diets, or chronic stress. Unlike acute inflammation (redness, pain), it is silent but contributes to fatigue, joint pain, and many chronic diseases. Fermented foods and a fiber-rich diet help reduce it.
→ Read also: Reducing inflammation: what your diet can really change
Inulin
A prebiotic fiber naturally found in chicory, agave, artichokes, and Jerusalem artichokes. Inulin selectively feeds bifidobacteria and lactobacilli, two families of beneficial gut bacteria. It also promotes calcium and magnesium absorption. minimiil uses organic agave inulin to provide a natural prebiotic effect.
K
Kefir
A traditional fermented drink rich in live probiotics. Original kefir is made from kefir grains (a symbiotic culture of bacteria and yeasts) grown in milk or sweetened water. minimiil offers almond kefir: a plant-based fermented drink made from almond milk, combining the benefits of traditional kefir with a 100% plant-based, lactose-free formula suitable for the whole family.
Almond kefir
A plant-based variation of traditional kefir, obtained by fermenting almond milk with probiotic cultures. Almond kefir combines the beneficial fats and nutrients of almonds with live probiotics from fermentation. It is the base of the minimiil recipe: a 60 ml fermented almond kefir shot, enriched with blackcurrant, blueberry, and basil, delivering 10 billion probiotics per serving.
L
Lacto-fermentation
A type of fermentation carried out by lactic acid bacteria (Lactobacillus, Leuconostoc, Pediococcus), which convert sugars into lactic acid. This process is used to produce sauerkraut, kimchi, pickles, yogurt, and kefir. Lacto-fermentation is one of the oldest food preservation methods and one of the most beneficial for the microbiome.
→ Read also: Lacto-fermentation: the future of food is already in your kitchen
Lactose
A sugar naturally found in cow’s milk and dairy products. Its digestion requires lactase, an enzyme that many adults produce in insufficient amounts (it is estimated that 65–70% of the global population becomes lactose intolerant after childhood, according to the NIH). Plant-based fermented drinks like minimiil are naturally lactose-free and therefore suitable for intolerant individuals.
M
Microbiome
The collection of genes carried by the microorganisms of the microbiota. While “microbiota” refers to the organisms themselves, “microbiome” refers to their collective genetic material. The human microbiome contains approximately 3.3 million genes — about 150 times more than the human genome. This genetic richness allows the microbiome to perform functions our own cells cannot, such as synthesizing certain vitamins (K, B12).
Gut microbiota
An ecosystem of 100 trillion microorganisms (bacteria, viruses, fungi, archaea) living in the human digestive tract, primarily in the colon. It weighs between 1 and 2 kg in adults. It performs essential functions: digesting fiber, producing vitamins (K, B12, B9), regulating the immune system, protecting against pathogens, and communicating with the brain via the gut-brain axis. Each person has a unique microbiota, comparable to a fingerprint.
→ Read also: The importance of the gut microbiome: why it matters and how to support it
Intestinal mucus
A layer of mucus lining the inner wall of the intestine. It forms a physical interface between gut microorganisms and intestinal cells while playing a role in the intestinal environment. Certain bacteria, such as Akkermansia muciniphila, use components of this mucus as a nutrient source and interact with its natural renewal processes. The relationship between dietary components, including fiber and polyphenols, and the intestinal mucus layer is an active area of scientific research.
P
Intestinal permeability (leaky gut)
An increase in the permeability of the intestinal barrier, which may allow certain substances, such as bacterial components, to pass more readily across the intestinal lining. Often referred to as “leaky gut,” this phenomenon is being studied for its potential associations with inflammatory processes and certain digestive conditions. The relationship between gut microbiome diversity, intestinal barrier function, and permeability remains an active area of scientific research.
Postbiotics
Beneficial substances produced by probiotics during fermentation: short-chain fatty acids (butyrate, propionate, acetate), vitamins, enzymes, and antimicrobial peptides. Postbiotics are considered one of the key mechanisms through which fermented foods exert their health benefits, even after live bacteria have been digested.
Prebiotics
Non-digestible food compounds — mainly fibers — that selectively stimulate the growth and activity of beneficial microbiome bacteria. The most studied include inulin, FOS, and GOS. They are found in garlic, onions, leeks, artichokes, bananas, and chicory. Not to be confused with probiotics: prebiotics feed bacteria, probiotics are bacteria.
Probiotics
According to the World Health Organization (WHO, 2001), probiotics are “live microorganisms which, when administered in adequate amounts, confer a health benefit on the host.” The most studied strains belong to the Lactobacillus and Bifidobacterium genera. They are naturally found in fermented foods (kefir, yogurt, sauerkraut, miso) or as supplements. minimiil delivers probiotics through the natural fermentation of almond milk — the bacteria develop directly in the drink, rather than being added afterward.
→ Read also: Which probiotic should you choose: food or supplements?
R
Athletic recovery and the microbiome
Intense physical activity causes oxidative stress and temporary inflammation, which affect the gut microbiome. Recent studies (Clark & Mach, Journal of the International Society of Sports Nutrition, 2016) show that athletes with a diverse microbiome recover faster, absorb nutrients better, and experience fewer respiratory infections. Probiotics and fermented foods help support the microbiome during intensive training periods.
→ Read also: Microbiome and sport: the gut as a hidden performance driver
S
Probiotic strains
Specific varieties of probiotic bacteria are identified by their genus, species, and strain (e.g., Lactobacillus rhamnosus GG). Each strain has its own characteristics and is studied for its interactions with the gut microbiome and various biological processes. This is why not all probiotics are identical: strain identity, dosage (CFU), and formulation are important factors to consider.
Synbiotics
Products combining probiotics (live bacteria) and prebiotics (fibers that feed them) in the same formulation. The idea is that prebiotics enhance the survival and effectiveness of probiotics by providing a growth substrate. minimiil is naturally synbiotic: almond kefir provides live probiotics, and agave inulin provides prebiotics.
V
Vitamin D
A fat-soluble vitamin essential for calcium absorption, bone health, and proper immune function. Vitamin D is mainly synthesized by the skin through sunlight exposure (UVB), but deficiencies are common — ANSES estimates that 80% of people in France lack sufficient vitamin D in winter. Growing children and athletes have increased needs. Each minimiil shot is enriched with vitamin D to help meet daily requirements.
