Fermented Foods and Their Benefits on Health

Human digestive systems are home to bacteria, most of which reside in the intestines. The gut microbiota plays essential roles, such as protecting the body against pathogens, regulating digestion and immune balance, and extracting nutrient components from consumed foods. Environmental factors, including diet, antibiotic use, and various illnesses, can alter this gut microbiota. Incorporating fermented foods and probiotic-rich foods or supplements into the diet has been shown to improve gut microbiota and positively affect physiological functions.

Fermented foods are defined today as “foods and beverages produced through controlled microbial growth and enzymatic transformations of food components.” Fermented dairy products result from adding suitable bacteria to heat-treated animal milks. Yogurt, kefir, sour cream, and cheese fall under the category of fermented dairy products. The nutritional content of milk changes after fermentation, leading to increased levels of phytochemicals and antioxidant activity.

Conjugated linoleic acid, naturally present in milk fat, exhibits anti-inflammatory, antioxidant, and anti-atherogenic effects, which increase during fermentation. For instance, folate, riboflavin, and vitamin B12 can be synthesized by the bacteria responsible for fermenting dairy products.

Fermented dairy products have preventive or healing effects on certain diseases:

Cancer:
Animal studies have demonstrated that lactic acid bacteria can provide anti-cancer effects, such as cancer prevention or suppression. Consumption of fermented dairy products may reduce the risk of breast and colon cancer. Specifically, yogurt, butter, and gouda cheese may offer protective benefits against breast cancer.

Type 2 Diabetes:
Particularly, yogurt consumption from fermented dairy products has been linked to a reduced risk of Type 2 diabetes and metabolic syndrome. Lower glucose levels, lower insulin levels, and less insulin resistance have been associated with yogurt intake.

Immune System:
Our immune system provides the first line of defense against microbial pathogens entering the body. Some studies indicate that yogurt or lactic acid bacteria can enhance the production of a group of immune cells or factors (such as cytokines, antibodies, T-cell production, etc.). Additionally, calcium, certain vitamins, and trace elements, as well as whey proteins, may contribute to strengthening the immune system.

Gastrointestinal Health:

• Diarrhea: Fermented dairy has been shown to reduce the incidence of diarrhea. Improvement is noted even in antibiotic-induced diarrhea or viral diarrhea.
• Constipation: Commonly seen in individuals following a Western diet and the elderly, some bacteria in fermented dairy products or probiotic supplements have been found to alleviate constipation.
• It helps facilitate digestion (such as reducing bloating and speeding up colon transit). It also reduces intestinal permeability and aids in alleviating symptoms of Irritable Bowel Syndrome (IBS).

Lactose Intolerance:
It is known that adults have more difficulty digesting lactose or milk sugar. For individuals with insufficient lactase in the small intestine, lactose consumption can lead to symptoms such as diarrhea, bloating, and abdominal pain. These symptoms are less common with fermented milk consumption. Yogurt aids in lactose digestion because the lactic acid bacteria used in making yogurt produce lactase and break down lactose. The beta-galactosidase enzyme produced by yogurt bacteria supports lactose digestion and increases tolerance to lactose.

Allergy:
Probiotic bacteria contribute to the healing of the intestinal lining and reduce intestinal permeability, thus preventing the absorption of antigens. This can prevent or reduce allergic reactions in individuals at high risk for allergies.

Dental and Bone Health:
Studies have shown that fermented dairy products support growth and bone density, reducing the risk of bone-related issues such as tooth decay and hip fractures. Moreover, it has been found that consuming yogurt and cheese alongside vitamin D supplements produces more favorable effects.

REFERENCES:

• D.A. Savaiano, R.W. Hutkins. Yogurt, cultured fermented milk, and health: a systematic review. Nutrition Reviews, Volume 79, Issue 5, May 2021, Pages 599-614, https://doi.org/10.1093/nutrit/nuaa013
• Nutritional Composition and Health-Promoting Properties of Amasi: A South African Fermented Milk Product. Fermentation 2022, 8(10), 493; https://doi.org/10.3390/fermentation8100493
• Fermented Dairy Products: Starter Cultures and Potential Nutritional Benefits. P.M. Panesar., Food and Nutrition Sciences Vol. 2 No. 1 (2011), Article ID: 3643, 5 pages DOI:10.4236/fns.2011.21006
• Impact on Human Health of Microorganisms Present in Fermented Dairy Products: An Overview. María Fernández, John Andrew Hudson, Riitta Korpela. Role of Microorganisms Present in Dairy Fermented Products in Health and Disease, Volume 2015 | Article ID 412714 | https://doi.org/10.1155/2015/412714