After eating carbohydrates, the digestive system breaks them down into glucose, which enters the bloodstream. The hormone insulin helps transport glucose into cells, where it can be used for energy or stored.
In people with insulin resistance, cells respond less effectively to insulin. Over time, this can contribute to elevated blood glucose levels and increase the risk of developing type 2 diabetes.
Researchers have investigated whether kefir could help improve certain metabolic markers because its microorganisms and fermentation products may influence digestion, inflammation, and insulin sensitivity.
A randomized clinical trial involving 60 people with type 2 diabetes examined the effects of consuming 600 milliliters of kefir daily.
The researchers reported improvements in certain blood glucose measurements compared with the control group.
A separate systematic review and meta-analysis published in 2021 examined randomized clinical trials involving kefir consumption and glycemic control.
The findings suggested that kefir may reduce fasting blood glucose and insulin levels. However, the reduction in glycated hemoglobin, commonly known as HbA1c, was not statistically significant.
More recently, a 2025 systematic review and meta-analysis of 24 interventional studies reported reductions in fasting glucose and HOMA-IR, a measure commonly used to estimate insulin resistance.
Nevertheless, the researchers also emphasized that additional studies are needed.
These findings are promising, but they do not establish kefir as a treatment for diabetes.
If you have diabetes, it is important to remember that kefir is not necessarily carbohydrate-free.
One cup of plain low-fat kefir may contain approximately 11.6 grams of carbohydrates, including naturally occurring sugars.
Flavored kefir products may contain considerably more added sugar.
For people monitoring blood glucose, the following practices may be helpful:
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Choose plain, unsweetened kefir.
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Check the nutrition label for total carbohydrates.
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Pay attention to portion sizes.
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Include kefir within your overall meal plan.
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Monitor your individual blood glucose response.
Never reduce or discontinue prescribed diabetes medication because you have started drinking kefir.
6. Kefir Contains Compounds With Potential Anti-Inflammatory Properties
Inflammation is a normal biological response that helps the body respond to injury, infection, and other threats.
Acute inflammation is generally beneficial because it helps initiate tissue repair and defend the body.
However, chronic low-grade inflammation can contribute to various health problems when it persists over long periods.
Scientists have investigated kefir because it contains several fermentation-derived compounds that may influence inflammatory processes.
One of these compounds is kefiran, a complex polysaccharide found in kefir grains.
Laboratory experiments have suggested that kefiran may influence inflammatory signaling pathways and help regulate immune responses.
Animal studies have also investigated whether kefir extracts can reduce inflammatory changes in different tissues.
For example, experimental research has examined the effects of kefir-derived compounds on gastrointestinal inflammation and models of colitis.
Some findings suggest that these compounds may help reduce inflammatory markers and protect certain tissues from inflammatory damage.
However, most of the evidence concerning kefir's direct anti-inflammatory effects comes from laboratory and animal studies.
It is not yet clear whether drinking ordinary amounts of kefir produces the same effects in humans.
Nevertheless, kefir can fit into an anti-inflammatory dietary pattern that includes other nutrient-rich foods.
Consider combining it with:
These foods provide different nutrients and bioactive compounds that support overall health.
7. Kefir May Contribute to Better Cardiovascular Health
Cardiovascular health depends on several factors, including blood pressure, cholesterol levels, blood vessel function, blood glucose regulation, and inflammation.
Because kefir contains beneficial microorganisms and nutrients, researchers have explored whether regular consumption could influence cardiovascular risk factors.
Some experimental studies suggest that certain kefir microorganisms may influence cholesterol metabolism and the production of compounds involved in blood pressure regulation.
For example, laboratory research has examined how specific bacterial strains isolated from kefir interact with cholesterol and bile acid metabolism.
Certain strains may bind cholesterol or influence the way cholesterol is processed in the digestive system.
Other research has investigated kefir-derived compounds and their possible effects on oxidative stress.
Oxidative stress occurs when the production of reactive molecules exceeds the body's ability to neutralize them. Excessive oxidative stress can damage cells and contribute to several chronic health conditions.
Kefir contains compounds that have demonstrated antioxidant activity in experimental settings.
However, these findings should not be interpreted as proof that kefir prevents heart disease.
A systematic review of randomized controlled trials published in Nutrition Reviews in 2023 found that human evidence concerning kefir's cardiovascular effects was limited.
Some studies suggested possible improvements in selected cardiovascular markers, but the results were inconsistent.
The most reliable approach to protecting your heart remains a combination of healthy dietary choices and lifestyle habits.
Drinking plain kefir may be one useful addition, particularly if it replaces a sugary beverage or less nutritious snack.
8. Kefir May Help Maintain Healthy Blood Pressure
High blood pressure, also known as hypertension, is a major risk factor for cardiovascular disease, stroke, and kidney problems.
It often develops without obvious symptoms, which is why regular blood pressure monitoring is important.
Researchers have investigated kefir as a possible dietary contributor to blood pressure regulation.
Some animal studies have reported that kefir consumption can reduce elevated blood pressure.
One proposed explanation involves the production of bioactive peptides during fermentation.
These peptides may influence angiotensin-converting enzyme (ACE), which plays an important role in regulating blood vessel constriction and blood pressure.
Some kefir-derived compounds have demonstrated ACE-inhibitory activity in laboratory experiments.
Kefir may also influence blood pressure indirectly through its possible effects on oxidative stress, inflammation, and the gut microbiome.
However, evidence from human clinical trials is still limited.
A systematic review of randomized controlled trials found some potential cardiovascular benefits, including possible improvements in hypertension, but emphasized that the available evidence was insufficient for firm recommendations.
Therefore, kefir should not be used instead of prescribed blood pressure medication.
People with hypertension should continue to prioritize established measures such as:
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Reducing excessive sodium intake.
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Eating plenty of vegetables and fruits.
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Maintaining a healthy body weight.
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Exercising regularly.
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Limiting alcohol.
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Avoiding tobacco.
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Following prescribed treatment.
Kefir can be part of a balanced diet, but its effects on blood pressure should not be overstated.
9. Kefir May Influence Cholesterol Levels
Cholesterol is a fatty substance that the body needs to produce hormones, vitamin D, and cell membranes.
However, elevated levels of certain blood lipids, particularly LDL cholesterol, can increase cardiovascular risk.
Some studies suggest that kefir may influence cholesterol metabolism through the activity of its microorganisms.
Certain bacterial strains may bind cholesterol in the digestive tract, while others may influence bile acid metabolism.
Because the liver uses cholesterol to produce bile acids, changes in bile acid recycling may potentially influence blood cholesterol levels.
Animal studies have reported encouraging results involving kefir-derived bacterial strains.
However, human studies have produced mixed findings.
One randomized clinical trial involving overweight or obese premenopausal women compared kefir, milk, and a control diet over eight weeks.
