How much Kefir should I drink per day?

Is there something like a "kefir overdose"?

Kefir daily dosage

Let’s make it clear first: there is nothing like a “Kefir overdose”. Unless you have a specific health condition or allergy that makes you hypersensitive to Kefir or any of its ingredients, there is no quantity of Kefir that could do any harm to you.

With that said, however, all bodies are different and may react to Kefir differently. Let’s remind that Kefir contains living microorganisms that will inevitably interfere with the host of bacteria that already live in all of us.

Kefir is the richest in probiotics fermented milk products with a long list of health benefits to children and adults. However, the first intakes of Kefir may cause temporary unpleasant sensations in the stomach and abdomen that may include flatulence or even diarrhea.

The first introduction of the biologically active bacteria and yeasts of Kefir may put our entire gastrointestinal tract into “overdrive mode” that may cause temporary discomfort. The good news is that this discomfort doesn’t last long and typically disappears on its own once the stomach and intestines adapt.

After this initial period of adaptation that usually lasts no more than a couple of hours up to a day, Kefir starts to be very well accepted by most people. Even higher daily intakes of Kefir (a liter or even more) are unlikely to cause any harm. Kefir has the inherent ability to balance the bacterial population in our guts, and any excess of the product gets naturally discarded from our bodies with no side effects.

Indeed, no one argues about the benefits of Kefir! It has always been at the leading edge of probiotic products that prevent and support the treatment of various diseases, including:

In addition, it is has been proven that Kefir may help you lose weight or even fight obesity, and it also has a wide range of positive effects on the skin and bones.

With all that said, however, Kefir is a potent probiotic containing a massive number of biologically active live bacteria. Therefore, it is always a good idea to drink Kefir moderately and by taking some precautions.

It is usually safe for anyone to drink two glasses of Kefir a day: one in the morning and the second before bedtime.

As we already said, it doesn’t mean that larger quantities would do any harm. These are only the recommended daily quantities for Kefir intended to provide optimal and long-lasting positive effects.

It is advised to have your first glass of Kefir in the morning (right before or with breakfast). At this time of the day, the acidity in the stomach is at its lowest level, which allows the live microorganisms of Kefir to safely pass through the harsh and highly acidic environment of the stomach.

It is also good to get a second glass of Kefir before bedtime because Kefir contains Tryptophan, which has a relaxing and calming effect on the nervous system and will ensure better sleep.

Let’s remind that Kefir is just a food, not a medication. While it is typical for medications to have specific prescriptions and dosages, the foods (Kefir included) don’t have any prescribed dosage. You can fairly consume as much Kefir as you like without running a risk of overdosing.

Some people (like me, the author of this article) can drink with the greatest pleasure one liter of Kefir a day, and sometimes even more. For others, however, such quantity may not be tolerated by their GI tract and may lead to temporary undesirable symptoms like bloating or diarrhea.

So, just like any other food, the way kefir will be accepted by your body entirely depends on … your body.

If you have never taken Kefir before, it is always a good idea to start carefully, with smaller quantities, and then increase them at your own pace, taste, and will.

Let’s repeat it: there is nothing like a “Kefir overdose”. Any excess of this probiotic drink will be safely and naturally eliminated from the body. You are not running any risk unless you have a specific medical condition considered a contraindication for Kefir consumption.

However, Kefir may be undesirable for people with gastric diseases associated with increased stomach acidity and will not benefit people prone to diarrhea since it may have a laxative effect.

On the other hand, if diarrhea is a symptom of a specific gastrointestinal disease like Irritable Bowel Syndrome (IBS), Kefir can even alleviate the symptom by restoring the bacterial balance in the guts.

Kefir belongs to fermented milk products, and like all products containing milk, it relieves stress, has a calming effect, relaxes both the muscular and nervous systems. That is due to the presence in Kefir of Tryptophan, an essential amino acid with significant importance for the nervous system because of its soothing and relaxing effect.

Today’s technological progress also has some negative consequences. For many people, the use of artificial and junk foods is a constant and inevitable occurrence. In these situations, Kefir becomes indispensable. It plays the role of a regulator of intestinal microflora and is suitable for many diseases in adults and children.

Kefir is easily absorbed by the body and improves all digestion processes. It has long been included in the main components of therapeutic diets, which doctors recommend for a series of bowel diseases.

However, since Kefir is still a rather sour product, it is not recommended for people suffering from high acidity of the stomach. On the contrary, it is highly recommended for people with below-average acidity of the stomach.

Drinking Kefir in huge quantities, especially to the detriment of other quality food products, may not be a good idea since such a “diet” can lead to an increasingly fast pace of the gastrointestinal tract.

Kefir causes significantly fewer allergic reactions than milk since it loses a significant part of the allergens during fermentation. That makes this product a popular choice for people prone to allergic reactions, but still, people with milk allergies should be cautious.

Kefir is included in many therapeutic and weight loss diets.

Additionally, in case of lactose intolerance (which is not a milk allergy!), lactose-intolerant people may very well tolerate Kefir as it contains far lower quantities of lactose compared to natural milk.


Kefir is undoubtedly an excellent fermented dairy product with a long list of beneficial effects on your health. Most medical professionals advise Kefir to both adults and children.

The recommended optimal quantity of Kefir for schoolchildren and adults is 0.5 liter (17 oz) per day, equivalent to two glasses of Kefir. The first glass of Kefir is good to be taken in the morning, before breakfast, and the second in the evening, right before bedtime.

On the other hand, there is nothing like a “Kefir overdose”. Any quantity of Kefir will be beneficial, provided that it makes you feel good and boosts your energy.

Kefir may not be advised only to people diagnosed with autoimmune diseases, with a compromised immune system, or undergoing immunosuppressive treatment.

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