Fermented foods have become popular in recent years, partly due to theirperceived health benefits.
For instance, there is some evidence that eating or drinking fermented foods can improve blood glucose controlin people with diabetes. They canlowerblood lipid (fats) levels and blood pressure in people with diabetes or obesity. Fermented foods can also improvediarrhoeasymptoms.
But can they help you lose weight, as arecent studysuggests? Let’s look at the evidence.
Remind me, what are fermented foods?
Fermented foodsare ones prepared when microbes (bacteria and/or yeast) ferment (or digest) food components to form new foods. Examples include yoghurt, cheese, kefir, kombucha, wine, beer, sauerkraut and kimchi.
As a result of fermentation, the food becomes acidic, extending its shelf life (food-spoilage microbes are less likely to grow under these conditions). This makes fermentation one of the earliest forms of food processing.
Fermentation also leads to new nutrients being made. Beneficial microbes (probiotics) digest nutrients and components in the food to produce new bioactive components (postbiotics). These postbiotics are thought to contribute to the health benefits of the fermented foods, alongside the health benefits of the bacteria themselves.
What does the evidence say?
Astudy published earlier this year has provided some preliminary evidence that eating kimchi – the popular Korean fermented food – is associated with a lower risk of obesity in some instances. But there were mixed results.
The South Korean study involved 115,726 men and women aged 40-69 who reported how much kimchi they’d eaten over the previous year. The study was funded by the World Institute of Kimchi, which specialises in researching the country’s national dish.
Eating one to three servings of any type of kimchi a day was associated with a lower risk of obesity in men.
Men who ate more than three serves a day of cabbage kimchi (baechu) were less likely to have obesity and abdominal obesity (excess fat deposits around their middle). And women who ate two to three serves a day of baechu were less likely to have obesity and abdominal obesity.
Eating more radish kimchi (kkakdugi) was associated with less abdominal obesity in both men and women.
However, people who ate five or more serves of any type of kimchi weighed more, had a larger waist sizes and were more likely to be obese.
The study had limitations. The authors acknowledged the questionnaire they used may make it difficult to say exactly how much kimchi people actually ate.
The study also relied on people to report past eating habits. This may make it hard for them to accurately recall what they ate.
This study design can also only tell us if something is linked (kimchi and obesity), not if one thing causes another (if kimchi causes weight loss). So it is important to look at experimental studies where researchers make changes to people’s diets then look at the results.
How about evidence from experimental trials?
Kefir, a fermented milk drink, reduced people’s appetite.
There have been several experimental studies looking at how much weight people lose after eating various types of fermented foods. Other studies looked at markers or measures of appetite, but not weight loss.
Onestudyshowed the stomach of men who drank 1.4 litres of fermented milk during a meal took longer to empty (compared to those who drank the same quantity of whole milk). This is related to feeling fuller for longer, potentially having less appetite for more food.
Anotherstudyshowed drinking 200 millilitres of kefir (a small glass) reduced participants’ appetite after the meal, but only when the meal contained quickly-digested foods likely to make blood glucose levels rise rapidly. This study did not measure changes in weight.
Anotherstudylooked at Indonesian young women with obesity. Eating tempeh (a fermented soybean product) led to changes in an appetite hormone. But this did not impact their appetite or whether they felt full. Weight was not measured in this study.
Astudyin South Korea asked people to eat about 70g a day of chungkookjang (fermented soybean). There were improvements in some measures of obesity, including percentage body fat, lean body mass, waist-to-hip ratio and waist circumference in women. However there were no changes in weight for men or women.
Asystematic reviewof all studies that looked at the impact of fermented foods on satiety (feeling full) showed no effect.
What should I do?
The evidence so far is very weak to support or recommend fermented foods for weight loss. These experimental studies have been short in length, and many did not report weight changes.
To date, most of the studies have used different fermented foods, so it is difficult to generalise across them all.
Nevertheless, fermented foods are still useful as part of a healthy, varied and balanceddiet, particularly if you enjoy them. They are rich in healthybacteria, and nutrients.
Are there downsides?
Some fermented foods, such as kimchi and sauerkraut, have added salt. The latest kimchi study said the average amount of kimchi South Koreans eat provides about 490mg of salt a day. For an Australian, this would represent about50%of the suggested dietary target for optimal health.
Eating too much saltincreases your riskof high blood pressure, heart disease and stroke.
This article is republished fromThe Conversationunder a Creative Commons licence.Read theoriginal article.
FAQs
The evidence so far is very weak to support or recommend fermented foods for weight loss. These experimental studies have been short in length, and many did not report weight changes. To date, most of the studies have used different fermented foods, so it is difficult to generalise across them all.
Does kimchi help you lose weight? ›
Fresh and fermented kimchi are both low in calories and may boost weight loss ( 49 ). A 4-week study in 22 people with excess weight found that eating fresh or fermented kimchi helped reduce body weight, body mass index (BMI), and body fat. Additionally, the fermented variety decreased blood sugar levels ( 50 ).
What happens to your body when you eat kimchi everyday? ›
Numerous studies have shown that a diet high in fermented foods, such as kimchi, has proven health benefits, such as increasing microbiome diversity and reducing inflammation. Another study, published in April in the Journal of Ethnic Foods, found that kimchi can be an effective treatment aid for obesity.
Does kimchi for breakfast help you lose weight? ›
While some studies have shown an association between kimchi consumption, weight loss, and an improvement in blood glucose levels, the evidence isn't convincing. You can still enjoy kimchi as part of a healthy, varied, balanced diet. Just be mindful of your total daily sodium intake.
Are kimchi pickles good for you? ›
Fermented foods contain high amounts of beneficial bacteria – the same kinds of bacteria that live and thrive in the human gut. Kimchi, sauerkraut, miso, tempeh and the humble pickle are all packed full of these good gut microbes.
Can eating fermented foods help you lose weight? ›
Regular consumption of fermented foods has been associated with a variety of health benefits (although some health risks also exist), including improved digestion, enhanced immunity, and greater weight loss, suggesting that fermented foods have the potential to help in the design of effective nutritional therapeutic ...
Does kimchi make you look younger? ›
Koreans may have found the fountain of youth. Scientists have speculated that their famously smooth skin and youthful appearance may be attributable to their diet. Kimchi, with its high antioxidant content, may help slow down the process of aging.
Does kimchi make your stomach flat? ›
Kimchi. Kimchi is a delicious, crunchy, tangy, and spicy Korean cuisine made of seasoned, salted, and fermented Napa cabbage and Korean radish. Due to fermentation, Kimchi comes loaded with friendly bacteria and probiotics that aid digestion, reduce belly bloating, and help flatten the tummy.
Is too much kimchi bad for your stomach? ›
Generally, kimchi is safe for most people unless you have a specific allergy to any of the ingredients. It may also cause some unpleasant side effects such as gas and bloating if you're not used to fermented or high-fibre food.
Are there any drawbacks from consuming kimchi? ›
Kimchi is high in sodium, with about 500 milligrams per cup. That's more than 20% of all the sodium that you're supposed to get in a day. Too much sodium can raise your risk of high blood pressure. If kimchi isn't prepared or stored properly, it can cause food poisoning, especially in people who are immune compromised.
Kimchi spoilage and over-fermentation
It will continue to ferment at a cool temperature. If kimchi over-ferments, it will have a very vinegary odor and taste. It is not pleasant to eat raw, so it is often used for soups and stews. If any fermentation gets soft and slimy, then it is a sign of spoilage.
Is kimchi in a jar good for you? ›
Kimchi is a Korean fermented cabbage dish left to ferment for 3-21 days in a jar. The taste can vary based on the ingredients and spices you add in. Kimchi has many vitamins and nutrients that help you create a balanced diet. The high sodium content in kimchi means you should not eat too much.
How much kimchi should I eat for weight loss? ›
Eating one to three servings of any type of kimchi a day was associated with a lower risk of obesity in men. Men who ate more than three serves a day of cabbage kimchi (baechu) were less likely to have obesity and abdominal obesity (excess fat deposits around their middle).
What happens if you eat kimchi on an empty stomach? ›
In short: it depends. Generally speaking, if your gut is in good shape and your body typically responds well to fermented foods, eating them on an empty stomach should be completely fine. “Fermented foods are typically fine to eat on an empty stomach since they help to support digestion,” Greenfield says.
What time of day should I eat kimchi? ›
As far as timing? It's most optimal to eat enzyme rich fermented food at the beginning of the meal, so they can begin the work of helping digestion as soon as they land in the stomach.
Is it okay to eat kimchi every day? ›
Kimchi is often served as a side dish alongside other healthful vegetables and proteins. Researchers noted in the study that consuming more than three servings of kimchi a day could have the opposite benefit. Participants who ate more than five servings of kimchi per day were more likely to be at a risk for obesity.
What is better, sauerkraut or kimchi? ›
The nutritional value of sauerkraut, kimchi, and pickles
Sauerkraut, for example, is a rich source of vitamin C and K, as well as fiber. Kimchi, a Korean staple, contains vitamins A, B, and C, and is believed to have anti-inflammatory properties.
Is shop bought kimchi good for you? ›
Along with fiber, vitamins, and minerals, kimchi contains natural probiotic bacteria. If you eat them regularly, the probiotics in fermented foods can be beneficial to your gut microbiome. Studies suggest that eating kimchi on a daily basis could help to improve some digestive problems.
What happens if you eat too much fermented food? ›
Due to the high probiotic content of fermented foods, the most common side effect is an initial and temporary increase in gas and bloating ( 32 ). These symptoms may be worse after consuming fiber-rich fermented foods, such as kimchi and sauerkraut.
Is apple cider vinegar a fermented food? ›
Apple cider vinegar is made through a process called fermentation. The process has two steps. First, the apples are crushed and yeast is added to speed up the fermentation process, so the sugar converts into alcohol after a few weeks.
The kimchi fermentation process is very short in comparison to making sauerkraut. Kimchi ferments at room temperature in only 1-2 days or more slowly in the refrigerator. For safety, kimchi should be stored refrigerated and is best eaten within 1 week, as the quality of kimchi deteriorates with longer fermentation.
Does kimchi make you gassy? ›
Some fermented foods such as kimchi and sauerkraut contain both the probiotic microorganisms and the prebiotic fibre that feeds their growth, resulting in a little extra gas and bloating. Therefore, moderation and variation are important considerations when introducing these to your diet. Salt consumption.
What does kimchi do to your stomach? ›
According to the Academy of Nutrition and Dietetics, including more foods like kimchi in your diet may help restore microbe balance in your gut, improve bowel function and give your immune system a boost.
Does kimchi count as one of your 5 a day? ›
Overall, however, kimchi is hugely beneficial as part of a healthy diet, thanks to the good it can do for your gut, the fact that it counts as part of your five a day, and — most importantly — is extremely delicious.
Does eating kimchi help your skin? ›
Koreans have long championed the skincare benefits of fermented foods. Kimchi, a fiery blend of fermented goodness, isn't just a culinary delight; it's a skin-saving secret. Bursting with lactobacilli, kimchi nurtures digestion and reduces inflammation, a dual action that tames acne and wards off premature wrinkles.
Is kimchi a detox? ›
Research shows that the multiple strains of bacteria (such as Leuconostoc mesenteroides, Lactobacillis brevis, and Lactobacillis plantarum) found in kimchi and sauerkraut, along with nutrients in cabbage are highly effective in helping the body detox from pesticides and other toxins.
Is kimchi a junk food? ›
Kimchi is a healthy food option. It is low in calories and high in many key nutrients. The process of making it gives it a high amount of good bacteria known as probiotics.
Kefir, a fermented milk drink, reduced people’s appetite.