When you think of weight-loss-friendly foods, you probably picture salads, fresh fruit, or smoothies. However, a new study suggests that kimchi, a mix of fermented cabbage and vegetables, could also be beneficial for weight loss, even if it isn’t a staple in Western diets.
The study explored the weight loss potential of consuming 60 milligrams of kimchi powder, which is roughly equivalent to almost an ounce of fresh kimchi—the amount you’d typically add to dishes like rice or noodles. Participants who took the kimchi powder capsules every day for three months lost a significant amount of body fat compared to those in a control group, according to findings published in the Journal of Functional Foods.
Dietitian Cindy Chou mentioned that these results aren’t surprising, considering the positive effects of eating fermented foods like kimchi regularly on gut health. This new study reinforces earlier findings, such as one from early 2024, showing that consuming three servings of fresh kimchi daily was linked to lower obesity rates in men.
Researchers from the Korea Food Research Institute’s World Institute of Kimchi noted their study was the first to evaluate kimchi’s anti-obesity effects using a randomized, double-blind, placebo-controlled approach, which is considered the gold standard in research.
In the study, 90 participants aged 20 to 65 with a body mass index (BMI) of 23 to 30 were recruited. For context, a BMI between 25 and 29.9 is categorized as overweight by the National Institutes of Health, while in Korea, a BMI of 23 or higher is considered overweight.
Participants were split into three groups. One group consumed powdered kimchi that was “spontaneously” fermented, made from cabbage soaked in salt water, mixed with red pepper, fish sauce, garlic, ginger, radish, and onion. Another group had powdered kimchi fermented with the bacterial starter Leuconostoc mesenteroides KCKM0828. The third group received a placebo containing lactose and kimchi flavoring.
After three months, the results showed notable weight differences. Both the spontaneously and bacterially fermented kimchi groups experienced significant reductions in body fat compared to the placebo group. On average, those taking spontaneously fermented kimchi lost about 1.32 pounds, while those with the bacterially fermented version lost around 1.96 pounds. In contrast, participants in the placebo group gained an average of 2.56 pounds over 12 weeks.
The participants’ gut microbiomes also showed interesting changes. Fecal samples indicated that those who consumed the kimchi capsules had more of the beneficial gut bacterium Akkermansia muciniphila, known for its positive impact on inflammatory bowel disease, obesity, and diabetes, and lower levels of Proteobacteria, linked to obesity.
Kimchi is low in calories, with just 22.5 per cup, but its weight loss benefits likely stem from the bacterial advantages of fermentation. The good bacteria introduced to the gut from fermented foods like kimchi can enhance digestion by fermenting dietary fiber into short-chain fatty acids, which help regulate appetite. Some studies suggest these acids can trigger feelings of fullness, curbing appetite and promoting weight loss.
A diverse gut might make weight loss easier. Human studies have shown a link between gut bacteria diversity and obesity. Some theories suggest these connections arise from how bacteria affect protein, fatty acid, and energy metabolism. Interestingly, losing weight can also promote a more diverse gut microbiome.
However, more research is needed to understand fully the gut bacteria differences between obese and non-obese people. While this study used powdered kimchi, it was made by freeze-drying, which preserves the live bacteria without affecting fiber and short-chain fatty acid content significantly. Therefore, fresh kimchi might have similar benefits.
If you’re thinking about adding kimchi to your diet, there are several ways to enjoy it. It can be a side dish, condiment, or flavor enhancer and pairs well with rice, noodles, soups, dumplings, grilled meats or tofu, and even as a topping for omelets, pizza, or grain bowls. You can also use it as a substitute for sauerkraut or pickled vegetables, adjusting the amount to your taste and preferences.
