Fermented foods such as kimchi may be one key to preventing obesity. A June 2020 study evaluated whether the Lactobacillus sakei bacteria derived from the Korean delicacy can cause weight loss in obese individuals, with promising results
Obesity is one of the most visible public health problems today, yet it also seems to be one of the most neglected. The World Health Organization has cited the "globesity" that rocks countries around the world, already exploding into a global epidemic.[i] The increased prevalence of obesity has been linked to increased death from Type 2 diabetes, high blood pressure, heart disease and some forms of cancer.[ii]
For those who are overweight or obese, diet is always one of the best places to start, and there is prevailing interest in the benefits of probiotics, found in fermented foods, in helping shed excess pounds. A 2016 clinical trial found a probiotic product with or without dietary fiber controlled body fat mass, with some bacteria strains reducing waist circumference and food intake.[iii]
Now, a June 2020 study investigates whether Lactobacillus sakei (L. sakei) bacteria derived from kimchi, a staple food in Korea, can contribute to weight loss in obese individuals.
L. Sakei Influence on Obesity and Gut Microbiota
L. sakei, commonly found in meat and fish, is used to ferment meat in Western countries. A previous study showed that its eight-week intake from Korean kimchi significantly slashed body weight and fat mass in animal models with high-fat diet-induced obesity.[iv]
The new randomized, double-blind, placebo-controlled clinical trial involved 114 obese individuals, or those with a body mass index (BMI) of more than 25 kg/m2.[v] The participants were randomly assigned to the L. sakei or placebo group for 12 weeks. The researchers then measured changes in body fat, weight and waist circumference.
After 12 weeks, the researchers saw a 0.2 kg reduction in body fat mass in the L. sakei group while finding a 0.6 kg increase in the placebo group. Waist circumference was also 0.8 centimeters (cm) smaller in the L. sakei subjects than those in the placebo group. BMI and body weight did not change, and adverse events were mild and similar between the groups.
Data suggested that L. sakei might be helpful in reducing body fat mass in obese individuals without serious side effects.
While recognizing limitations in their study, including the need to probe significant body fat and weight changes beyond 12 weeks of treatment, the researchers cited evidence that food changes the human gut microbiota -- and diet plays an important role in the gut's bacterial environment and the progression of obesity. The gut microbiota is an extremely complex, abundant group of microbes that colonize the human body and radically influence health.[vi]
"[C]hanges in the composition of the gut microbiota may contribute to alterations in body weight and composition," the researchers wrote.[vii]
Gut-derived short-chain fatty acids (SCFAs) have been previously found to cause weight regulation through their stimulatory impact on anorexigenic (appetite suppressing) gut hormones and in the increase in the synthesis of the satiety hormone leptin.[viii]
Kimchi and Overall Wellness
Kimchi, consumed by Koreans as a salted and fermented vegetable side dish for about 2,000 years, packs so many health benefits as a probiotic. All of kimchi's traditional ingredients are health-boosting foods in their own right: cruciferous vegetables, garlic, ginger and red pepper, to name a few. Here are other studies that point to kimchi's wondrous effects on human wellness:
Strong immune system -- A study concluded that the probiotic Lactobacillus plantarum (L. plantarum) 200655 isolated from kimchi has antioxidant and immune-enhancing properties.[ix] This makes the strain ideal for older people.
Anticancer action -- Korean researchers developed a kimchi recipe boosting its anticancer action, adding mustard leaf, Chinese pepper and Korean mistletoe extract. Lab tests on human colon cancer cells revealed that the mistletoe extract increased inhibition rate from 62% to 80%.[x]
In a long-term study, a Chinese group found that Helicobacter pylori (H. pylori) treatment for two weeks coupled with vitamin or garlic supplementation for seven years were associated with a significantly reduced risk of death from gastric cancer for over 22 years.[xi]
Both treatments were also linked with greatly reduced incidence of the cancer. Kimchi, with its known anti-carcinogenic potential,[xii] is made from Chinese cabbage -- this vegetable contains sulforaphane, a potent H. pylori-fighting compound.
Anti-diarrhea -- Exopolysaccharide from L. plantarum offered protection against rotavirus-induced diarrhea and regulated inflammatory response. The probiotic strain was one among 263 strains found in 35 samples of kimchi.[xiii]
Healthy lipid profile -- In a study of 102 healthy Korean men ages 40 to 64 years, researchers associated eating up to 453 g of kimchi a day with higher HDL cholesterol and lower levels of LDL cholesterol.[xiv]