A MICROSCOPIC VIEW OF THIS CHAPTER
• The idea of probiotics has existed for centuries.
• Probiotics were discovered at the end of the 19th century.
• Probiotics have healthy benefits.
• The makeup of microbes in your body changes with age.
• Recently, probiotic research has exploded and new discoveries happen frequently.
• Today probiotics are used around the world and new products are prevalent.
• The original source of probiotics varies.
Microbes, such as bacteria, existed long before humans evolved. These little organisms can be found on the tops of mountains, the bottom of the deepest oceans, in the intestines of animals and even in the frozen rocks and ice of Antarctica. Human history has been shaped by our interactions with microbes. Cholera, small pox and the plague are examples of how microbes have put humans at their mercy. However, these small creatures can also be as much of a blessing as a problem.
History is full of claims that living microbes in food, particularly lactic acid bacteria, can improve health. Remember that many probiotics are lactic acid bacteria. People have eaten fermented milk products which contain lactic acid bacteria since prebiblical times. In the Bible and the sacred books of Hinduism there are mentions of cultured dairy products being eaten. Other cultured dairy products, such as kefir and koumiss, originated many centuries ago. Kefir, derived from the Turkish word keif, which loosely translated means “good feeling,” originated in the northern Caucasus mountains in Russia. Koumiss, a fermented alcoholic beverage prepared from milk, was known to the Scythians (7th century BC), according to the famous Greek historian, Herodotus. Today, in the same area of the world, which is now referred to as Siberia, fermented milk products are a staple in the diet.
The first scientist to identify a healthy bacteria, which is now classified as a probiotic, was Louis Pasteur, a French scientist. Pasteur identified Lactobacillus in the 1850s. This bacteria was found to occur naturally in yogurt and improved the health of people who ate it.
DISCOVERY: BACTERIA CAN HELP YOU
In the early 1900s, a predecessor of Pasteur’s, Russian immunologist Dr. Eli Metchnikoff, suggested that a synergistic interaction exists between bacteria and their host. Metchnikoff noted the longevity of Bulgarian peasants who ate a lot of yogurt. He proposed that a link existed between better health and longer life and the consumption of lactic acid bacteria (probiotics) delivered to the intestine via yogurt. Dr. Metchnikoff ’s subsequent work on cellular immunity won him the Nobel prize in 1908.
Meanwhile, around 1900, Dr. Henry Tissier discovered Bifidobacteria. Tissier recommended the administration of Bifidobacteria to infants suffering from diarrhea, claiming that Bifidobacteria gets rid of the pathogenic bacteria that cause the disease. He also showed that Bifidobacteria were predominant in the gut flora of breast-fed infants.
Research in the area of probiotics was slow for many years after this groundbreaking discovery. However, researchers were able to uncover a better understanding of the relationship between probiotics and the human intestinal tract.
DISCOVERY: PROBIOTICS PREVENT DISEASE
In the 1950s, scientific research in probiotics had a renewed interest. It was a group of scientists led by Freter, Collins, Carter and Bohnohoff who broadened our understanding of probiotics. They discovered that intestinal microflora helps an animal be resistant to disease. They discovered that mice that were given oral antibiotics, which kill all bacteria, including probiotics, were more susceptible to infection. As well, animals with microflora in their intestines had a better chance of survival than those with none. Their research offered more proof that good microflora (probiotics) offers protection from infections.
The term probiotic was not actually coined until the 1960s. Lilly and Stillwell first defined probiotics as “substances produced by microorganisms which promote the growth of other microorganisms.” In 1974, Parker elaborated on the definition of probiotic to also include, “organisms and substances which contribute to intestinal microbial balance.”
DISCOVERY: MICROFLORA CHANGES AS WE AGE
Definition of Probiotic
In October, 2001, an Expert Consultation meeting convened by the Food & Agriculture Organization (FAO) and World Health Organization (WHO) defined probiotic as “live microorganisms which when administered in adequate amounts confer a health benefit on the host.”
This definition has the following characteristics:
• Probiotics must deliver a measured physiological benefit, substantiated by studies conducted in the target host.
• Probiotics need not be restricted to food applications or oral delivery.
• A definition of probiotics should not limit the mechanism of action.
• Probiotics must be alive.
Although it was recognized that dead cells may have health benefits, the consultants suggested that a different term be used for dead cells to reflect to the consumer that probiotics are alive.
In 1978, Dr. Tomotari Mitsuoka, a Japanese scientist, wrote Intestinal Flora and Health, still one of the main references in the study of lactic acid bacteria today. Mitsuoka illustrated how the composition of intestinal flora changes during a lifetime. He also demonstrated how amounts of Bifidobacteria in the intestines decrease with age, increasing our risk of colon disease. His work supported the theory that the oral administration of probiotics, including Bifidobacteria, improves intestinal flora balance and helps prevent the development of lower bowel conditions.
MORE DISCOVERIES EVERY DAY
Thanks to these forefathers of probiotic research, today many potential health benefits of probiotics are being studied. Lactic acid bacteria play a key role in restoring and maintaining intestinal flora balance and enhancing immune system functions. Recent research is investigating lactic acid bacteria’s potential hypocholesterolemic effects (lowers blood cholesterol levels), use as a treatment for urogential and vaginal diseases, as well as their role in colon cancer prevention and asthma. Plus, probiotics are being studied for their potential role in heart disease, oral health, prevention of the cold and flu, HIV-associated diarrhea, treatment of superbugs and much more. Researchers are also discovering more bacteria and yeasts that demonstrate probiotic effects and are showing promise as future therapies for diseases in humans.
FROM THE LABORATORY TO YOUR PLATE
The ability to take this research knowledge and transform it into easy, at-home therapies is what makes probiotics such a fascinating area. The hard work of these early researchers was first applied to products by the Yakult Company of Japan in the 1930s. Yakult Company introduced a fermented milk product that contained a probiotic culture. Today, Yakult milk product can be found in many countries around the world, including Australia, Europe and Taiwan. In Japan, one can find dozens of probiotic products on supermarket shelves, ranging from fortified milks to candy containing Lactobacilli and Bifidobacterium strains. In Chapter 18, we’ll take a closer look at some of these products available on supermarket shelves.
The probiotic food trend is evident around the world. Most popular in Japan, probiotics are consumed to a lesser degree in Europe. The use of probiotic supplements in Europe is a booming segment of the supplement market. In fact, market data shows that probiotic drinks made up 30% of the functional food market in Europe just after the turn of the century. In Europe, the dairy sector is the most developed segment of the probiotic market. Fermented milks, probiotic drinks and yogurts are sold in convenient “daily dose” formats. These are the most widely used formats in Europe. However, consumer acceptance of probiotic products varies greatly across the region. For example, Scandinavian and Northern European countries that have a long tradition of eating fermented dairy products have the highest acceptance of probiotics. Other regions in Europe are slower to come on board. North America is also slowly joining in the probiotic movement.
North Americans are less accepting of probiotics than Europeans. An interesting difference is that North Americans are more willing to take a supplement than their European counterparts. This may explain the popularity of probiotic supplements despite the relatively low number of probiotic foods available in North America versus other global regions. However, a change is occurring as can be seen by the influx of probiotic foods in the North American market since the turn of the century. Probiotic yogurts entered the mainstream North American supermarket aisles early in the 21st century. Probiotic milks and cheeses slowly followed suit. The supermarket landscape in North America changed quickly as major probiotic manufacturers were teaming up with large U. S. dairy and food companies to produce more probiotic functional foods such as smoothies, candy, cereals and other fortified food and beverage items. This boom in innovative probiotic products in North America can also be seen around the world. Advances in probiotic research are likely fueling this growing interest in probiotics by the public. The boom in probiotics is not just latest health food flavor of the month—probiotics are supported by strong evidence that they support good health. They have been referred to as the next essential fatty acids (omega-3s) or the new vitamins. Probiotics are more than just the latest new cheese or yogurt, they are the next step in nutritional wellness.
WHERE DO PROBIOTICS COME FROM?
Where do all of these species of probiotics come from? Most of today’s lactic acid bacteria strains used in probiotic supplements were isolated approximately 20 years ago from human, dairy and vegetal origins. It is these same strains that are found in the probiotic foods and supplements on the supermarket shelves today. Research conducted over two decades ago is relevant today, as the bacteria strains are the same. The same strains that were isolated 20 years ago and used in initial research studies are the same strains used in research today.
How did researchers isolate the probiotic strains? Research labs and universities used a three-phase method to select these strains.
• Phase 1. The Mother-strain or original probiotics is isolated using a process called colony selection process. Then, the strain is purified and identified. Researchers achieve this by a testing method called Analytical Profile Identification.
• Phase 2. The researchers look for the characterisitics of the probiotic strain such as its ability to survive and reproduce. These two characteristics are important if a probiotic is to surivive on the supermarket shelf and be able to reproduce in your intestines. Researchers can then determine what production methods should be used to maximize bacterial growth.
• Phase 3. Researchers discover the characteristics of the probiotic strain. Different tests define the exact characteristics of the strain. These characteristics include the probiotic strain’s ability to fight bad microbes, produce enzymes that promote nutrient absorption and vitamin production and more. By identifying the characteristics of the strain, researchers can select the best probiotic for your health. In other words, all of this detailed work by scientists ensures that the probiotic strains found in today’s products are those that offer us the best health benefit.
Today, probiotic manufacturers can offer consumers around the world safe and effective dosages of probiotics thanks to the long hours spent in laboratories by our scientific predecessors. Every day, researchers gain a greater understanding of the mechanisms of probiotics. However, it will likely take many decades more before the specific health benefits of each probiotic strain is fully understood. Until that time we can focus on what we do know: the use of a diversity of probiotic strains supports your health by boosting your immune system, improving your ability to uptake nutrients and helping to prevent and treat some disease conditions.
SUMMARY
Probiotics were discovered before the turn of the 20th century; however, research was slow in this field for the next hundred years. Over this time researchers discovered that probiotics can prevent disease and that a person’s microflora changes with age. The term probiotic was first introduced in the 1960s, but a firm definition was not created until 2001. Today, new discoveries about probiotics are emerging at a rapid pace. New technology and growing interest by consumers is fueling this probiotic movement. On the market, dairy-based probiotics have been in existence in Japan for many years and are popular in Europe. North America is quickly increasing its interest in probiotics. The global interest in probiotics has resulted in a surge of innovative foods that contain probiotics. Researchers are linking probiotics with a wide array of health benefits and the number of disease conditions they are thought to benefit continues to grow.
