Feature: The Evolution Of Yogurt©


Alternavita Magazine© Feature Article

The Evolution Of Yogurt

More than a century after Élie Metchnikoff, how has his theory shaped our understanding of useful organisms?

The “Father Of Natural Immunity” is credited with our modern understanding of immunity

Élie Metchnikoff developed a theory that aging is caused by toxic bacteria in the gut and that lactic acid could prolong life. Based on this theory, he drank sour milk every day. He attributed the longevity of Bulgarian peasants to their yogurt consumption.

The perceptions of Leo Tolstoy after meeting 1908 Nobel Prize winner, Metchnikoff on his grand tour: For this “Old Testament prophet”, science was both a religion and an addiction. “He believes in science as in Holy Scripture, he is a sweet and simple man but as some weak men get drunk on alcohol, he gets drunk on science.”

More than a century after Élie Metchnikoff, “The Father Of Natural Immunity” received his Nobel Prize, and is credited with our modern understanding of natural immunity, how has his theory shaped today’s understanding?

The term “probiotic”, is generally attributed to Metchnikoff

Probiotics are live microorganisms intended to provide health benefits when consumed, generally by improving or restoring the gut flora. The introduction of a hypothesis similar to the modern concept, but not the term, “probiotic”, is generally attributed to Metchnikoff, who suggested that “the dependence of the intestinal microbes on the food makes it possible to adopt measures to modify the microbiota in our bodies and to replace the harmful microbes by useful microbes”.

It doesn’t just sound similar, it is the hypothesis and it gave rise not only to the term probiotic but prebiotic and the two should not be confused but they are closely intertwined. Prebiotics are chemicals or substrates that induce the growth or activity of microorganisms.

Personal credibility to his theory

Metchnikov was an atheist and Darwinist and despite two suicide attempts, the first with injected ‘pathogens’ both he and his second wife survived for decades with relapsing fever and typhoid, lending some personal credibility to his theory of useful microbes. He succumbed to heart failure at age 71 in 1916. His second wife, who contracted typhoid and was infected for nearly 50 years, died in 1944. His first wife died of tuberculosis, followed by his first suicide attempt with opium.

Probiotic research began with infectious diarrheal disease

Current research on the efficacy of probiotics include such conditions as metabolic disease, antibiotic-associated and C. difficile-associated diarrhea, IBS, constipation, IBD, chemotherapy- associated diarrhea, respiratory tract infection, ventilator-associated pneumonia, NAFLD, liver encephalopathy, periodontitis, depression, vaginosis, urinary tract infections, pancreatitis, pneumonia, hospital infection, mortality of post- trauma patients and necrotising enterocolitis in premature infants.

The study of the microbiome and ‘useful organism providing benefit’ to its host is an extremely complex subject in light of microbial science and plague ridden history and has taken many years and enormous cost in research dollars to determine some ‘useful benefits‘ of microbes.

Complexity hampers research

Studies are both conclusive and contradictory. Research efforts are hampered by many factors, including:

  • the complexity of the human microbiome
  • inability to clinically define “healthy microbiome”
  • age, location, diet of test subjects
  • host and bacteria interaction complexity
  • failure to achieve ideal systematic testing procedures to determine benefits to a human host
  • effects of various drugs and their long term implications
  • the disparity in the formation of the microbiome in infants
  • low compliance in achieving known ‘gold standards’ in microbiome formation in clinical settings in infants
  • generational decline affecting controls 
  • the scope in which numerous conditions and diseases are affected by the gut 
  • complexity in bacterial interaction

While the hurdles are enormous in determining the beneficial effects of probiotics to the human vs. the animal host no one is doubting the consensus that the gut system axis is reshaping research and medical history. That the beneficial effects may be shown to be species specific adds another layer of complexity as this presents a problem with long held scientific beliefs that to date have not been challenged as rigorously as one would expect. Consensus has not been established for minimum understanding or analysis in light of technological advance. The failure to reach agreement in analytic techniques has stalled clinical applications. Historical gold standards based on the scientific method have yet to be replaced, leaving medical consumers with a plethora of confusing data, often influenced and funded by outside sources with undisclosed competing interests that travel uninterrupted from institutions and in to established medical journals and later disseminated without rigor.

How can the average consumer begin when reading about ‘benefits’?

Microbial influence is greatly affected by the host.

“The terrain is everything.”

Determine if the probiotics are GRAS, generally regarded as safe. Is the probiotic readily available to consumers with virtually no detrimental public health outcomes? In that case you can usually rest assured it is a ‘pro-biotic’.

Understand prebiotic effects

It was never proposed that probiotics be consumed apart from their natural environments, cheese and many fermented foods were readily available until the modern marketplace gave rise to ‘probiotic capsules’ or powders and health benefit was implied. That assumption was challenged and it soon gained traction.

By nature probiotics make ‘health claims‘ as ‘living organisms beneficial to a host‘, providing legal fodder in the regulatory setting that may be prohibited based on the term ‘probiotic‘ alone.

In conclusion.

Élie Metchnikoff has an established place as the “Father Of Natural Immunity” but did his hypothesis hold water or open too many cans of worms for medical consumers awaiting confirmation of long ago prophesied pro-benefits.

While Metchnikoff proposed longevity, he did not promise immortality while waiting for consensus from his cohorts for his theory of probiotics to be reached. Luckily for him, Bulgarian peasants didn’t take a century to find benefit in useful organisms and today yogurt is readily enjoyed by many cultures and his hypothesis is gaining almost limitless research attention.

14 clinically shown benefits of probiotics

  1. Type II diabetes Reduction of glucose and glycated hemoglobin
  2. Dyslipidemia Reduction of total cholesterol and LDL cholesterol
  3. Hypertension Improvement in blood pressure, especially if the basal blood pressure is high
  4. Helicobacter Pylori Significant improvement of the eradication rate of bacteria
  5. Chronic Inflammatory Bowel Diseases Practical option in ulcerative colitis both as induction therapy that maintenance
  6. Constipation Improvement in whole gut transit time, stool frequency and stool consistency
  7. Atopic syndrome and hypersensitivity to food Reduction in eczema infant, improvement of atopic syndrome
  8. Respiratory tract infections Reduction in the incidence of symptoms of respiratory tract infections
  9. Non alcholic fatty liver disease (NAFLD) NAFLD decrease in liver aminotransferase levels and improving insulin resistance
  10. Encephalopathy Probiotics decrease overt hepatic encephalopathy in patients with liver cirrhosis
  11. Periodontitis Use as an adjunct to non- surgical periodontal treatment of chronic periodontitis
  12. Depression Decrease in the score on the depression scale
  13. Children born prematurely Reduction of sepsis, both bacterial and fungal origin, that reduced incidence of severe necrotizing enterocolitis
  14. Post-trauma patients Reduction in the incidence of hospital infections, Ventilatory- associated pneumonia and length of intensive care


Contributions Of Élie Metchnikoff To Immunology Today

“I rather believe that the essence of an inflammation lies in the phagocyte attack of solid pathogenic substances, be it a weakened or dead cell, a bacterium or any other foreign body.” These words written by Metchnikoff in his 1883 publication clearly put phagocytes in the first line of defense against pathogens. In the same publication, he also wrote: “… I concluded that the so-called serous inflammation represents an acquired trait, whereas the accumulation of phagocytes constitutes something more primal in the inflammatory response.”

  • Distinct macrophage populations exist that are all subjected to many different stimuli that modify their gene expression. Macrophages submitted to classical (Th1) pathway are activated by IFN-γ or LPS, whereas macrophages going through the alternative (Th2) pathway are activated by cytokines, such as IL-4, IL-10, or IL-13 .
  • The concept of macrophage polarization has already been shifting to a more complex and dynamic vision of macrophage activation that goes beyond the dichotomy of M1/M2 classification.There appears to be a whole spectrum of polarized macrophages or signatures, hence the need for a different approach to describe the infectious disease process beyond a bridge between innate and adaptive immunity.


How should I take probiotic capsules if I don’t like yogurt or kefir?

Alternavita – Right Track News

The higher protein concentration of infant formulas compared with breast milk has been suggested to be a source of metabolic stress on tissues such as the liver and kidneys in the still-developing infant. It is also thought to be a contributing factor to growth differences observed between formula-fed and breastfed infants. In a double-blind randomized controlled trial, 21 fed infants standard formula or α-lactalbumin–enriched formula (25% of total protein vs 11% in the standard formula) from 6 weeks to 6 months of age and compared them with breastfed infants. The protein content of each formula was 13.1 g/L. Compared with infants fed the standard formula, infants fed the α-lactalbumin–enriched formula had a growth pattern more similar to that of breastfed infants and plasma amino acid concentrations similar to or higher than those of breastfed infants.
Intestinal barrier loss alone is insufficient to initiate disease in IBD. A dysfunctional autophagic mechanism leads to chronic intestinal inflammation in IBD. The maintenance of gut mucosal equilibrium requires a balance between enterocyte loss by apoptosis and the generation of new cells by proliferation from stem cell precursors at the base of the intestinal crypts. Macrophages functions change during infection and inflammation. The intestinal macrophage pool requires continual renewal from circulating blood monocytes, unlike most other tissue macrophages, which derive from primitive precursors that subsequently self-renew.
SIBO can produce a mild to severe chronic encephalopathy. Gasotransmitters operate independently of immune receptors. Previously researchers have thought of signaling pathways as entailing a ligand binding to a receptor. However, gases can also trigger signaling cascades in the body. The best known is nitric oxide, or NO, which regulates a host of functions, notably blood pressure. H2S has a high co-morbidity with seizure activity.The liver has long been recognized as the primary organ of detoxification but, there is now growing evidence that the gut also plays a central role in the detoxification process. Given that the small intestine functions predominantly as an absorptive organ its significance in the metabolism of non-nutritive dietary constituents and xenobiotics seems to have been significantly underestimated. This is in spite of the fact that the small intestine is the first site of xenobiotic exposure and that, over the course of a lifetime, is presented with the largest load of antigens and xenobiotics confronting the human body.
Given that the small intestine functions predominantly as an absorptive organ its significance in the metabolism of non-nutritive dietary constituents and xenobiotics seems to have been significantly underestimated. Detoxification begins at the tips of the villi and the gut is equal to the liver for detoxification.
Macrophages functions change during infection and inflammation. The intestinal macrophage pool requires continual renewal from circulating blood monocytes, unlike most other tissue macrophages, which derive from primitive precursors that subsequently self-renew.
The vitamin D binding protein (DBP) was initially discovered as a major liver-derived polymorphic protein and called group-specific component or Gc. Vitamin D Binding Protein is otherwise know as: VDBP Gc-Protein Glycoprotein Transport protein Gc-Globulin. In general, total Gc-globulin levels are decreased in all patients with hepatotoxicity. Patients with ALF (Acute Liver Failure) have total Gc-globulin concentrations of approximately 100 mg/L which is less than one third of normal values.
Acute liver failure (fulminant hepatic failure) and prognosis. It is safe to say that acute liver failure (ALF) is one of the most dramatic conditions in medicine. The failing liver leads by definition to hepatic encephalopathy within a short time after initial symptoms and may also lead to a cascade of organ failures including renal failure, circulatory collapse, and pulmonary dysfunction. Further, severe infections, deep coagulopathy, and the risk of cerebral edema, intracranial hypertension, and cerebral herniation adds to the picture of an extreme disease entity. Not surprisingly, the mortality rate in ALF has historically been very high, with survival being the exception to the rule. So far, eleven clinical studies regarding Gc-globulin and ALF have been published. Eight studies have reported on total Gc-globulin levels. The results were very similar among the studies; Gc-globulin concentrations were reduced to between 25% and 49% of normal. Free Gc-globulin levels (reported in 5 studies) were even lower, between 12% and 26% of normal, and complex ratios (reported in 5 studies) were elevated in all papers. Thus, the stress on the actin scavenger system in ALF seems very obvious.


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