Kefir vs yoghurt: which is healthier?
Kefir and yoghurt are similar fermented dairy products with various health benefits, especially for gut health. Here we explore the differences, learn about their individual uses and find out whether kefir or yoghurt is better for your health. (There’s also non-dairy kefir, but we won’t get into that here.)
The fermentation process
There are some important differences in how kefir and yoghurt are fermented.
Kefir: mixed fermentation
Kefir contains a diverse array of probiotic strains, more so than most other fermented products - whether they are dairy or not. This diversity is due to the various bacteria strains (and yeasts) found in kefir grains. Some of the most common microbes found in kefir include:
Lactobacillus species: These are usually the most abundant bacteria in kefir. They include strains like Lactobacillus acidophilus, Lactobacillus casei and Lactobacillus kefiri.
Streptococcus species: Including Streptococcus thermophilus which is another beneficial bacteria.
Lactococcus species: Such as Lactococcus lactis, which are involved in the fermentation of lactose, making kefir more digestible for people with lactose intolerance.
Acetobacter species: These give kefir its characteristic acidic flavour.
Yeasts: Kefir also contains beneficial yeasts which are not typically found in yoghurt. These yeasts have been linked to various health benefits.
Leuconostoc species: These bacteria contribute to the carbonation and creamy texture of kefir.
As you can see, kefir provides a hugely diverse range of probiotics and other microbes. This is in contrast to some other commercial fermented products such as kombucha which often only have one probiotic strain present. The diversity of microbes in kefir makes it one of the best fermented products for gut health.
Read our review of M&S x Zoe kefir gut shot which has 14 probiotic strains.
Yoghurt: bacterial fermentation
Yoghurt typically contains a more limited range of probiotic strains compared to kefir. The most common probiotic strains found in yoghurt include:
Lactobacillus bulgaricus: This is one of the primary bacteria used in the fermentation of yoghurt. It plays a key role in the development of yoghurt's characteristic taste and texture.
Streptococcus thermophilus: This is another primary bacterium used in yoghurt production. It works with Lactobacillus bulgaricus to ferment the lactose in milk, producing lactic acid, which gives yoghurt its tangy flavour and thick texture (by interacting with milk proteins).
Some yoghurts, especially those labelled as containing ‘live and active cultures’, may also include additional probiotic strains such as Bifidobacteria and Lactobacillus acidophilus which contribute to a healthy microbiome.
Texture and consistency
Kefir: drinkable
Kefir has a thinner, more liquid consistency compared to yoghurt which makes it drinkable. I’ve never managed to conclusively determine why this is as there are varying opinions about this. Some claim it is because the far more diverse microbes (including lactic acid bacteria, acetobacter and yeasts) are able to eat through more of the sugars compared to yoghurt. It also might be because the yeasts produce a small amount of alcohol which thins out the liquid.
In any case, the result is a runny, drinkable and sometimes very slightly effervescent drink. This texture makes it suitable for drinking on its own, or added to smoothies or poured on cereal.
Yoghurt: thick and creamy
Yoghurt has a thicker, creamier texture. This is achieved through the fermentation process, where the development of lactic acid causes milk proteins to coagulate, creating a firmer structure. Greek yoghurt, in particular, is even thicker due to the straining process that removes whey, concentrates the proteins and gives it a rich and creamy texture.
Taste profile
Kefir: tangy and sour
Kefir has a more pronounced tangy and sour taste compared to yoghurt. This is due to the presence of a wider variety of fermenting organisms, including yeasts and acetobacter, which contribute to its complex flavour profile. This flavour can initially seem a bit funky and some people find it to be an acquired taste.
Yoghurt: mild and less sour
Yoghurt tends to have a milder, less sour flavour than kefir. This makes it a versatile base for both sweet and savoury dishes. The flavour of yoghurt can also vary depending on the fat content and protein content, which is especially high in strained Greek yoghurt.
Probiotic content
Compared to yoghurt, kefir has a better probiotic quality - both in terms of the diversity of probiotic strains and the quantity of probiotics. The yeast in kefir, not typically found in yoghurt, also offer health benefits.
It’s worth noting that some yoghurts are also fortified with additional probiotic strains to enhance their health benefits, however this still doesn’t match the diversity in kefir.
Read about the health benefits of probiotics.
Nutritional content
Both kefir and yoghurt are excellent sources of essential nutrients. They are rich in calcium which is crucial for bone health, and rich in protein which is important for muscle repair and growth. They also contain B vitamins which play a vital role in energy metabolism, and potassium which is necessary for heart health.
Lactose content and digestibility
Kefir: lower lactose levels
Kefir's complex fermentation process breaks down much of the lactose, making it often more suitable for individuals with lactose sensitivity and generally more digestible.
Yoghurt: more lactose
Yoghurt generally contains more lactose than kefir, however the fermentation process does significantly reduce the lactose content of the original milk.
Use in cooking
Kefir: liquid-based recipes
Kefir's thinner consistency makes it ideal for smoothies and salad dressings. Its tangy flavour can also add a unique twist to recipes.
Yoghurt: more versatile
Yoghurt's versatility in cooking is extensive. It's used in a variety of ways including in sauces, marinades and baking. Its thicker texture makes it suitable for creating creamy dressings and dips, and it can be a healthier substitute for sour cream or mayonnaise in recipes.
Origin and cultural significance
Kefir originated in the North Caucasus and spread particularly though eastern Europe and southwest Asia. It has a long history in these regions, where it's been consumed for centuries and is integral to the traditional diets of these areas.
Yoghurt is more common around the world these days and is a staple in many cuisines including Greek, Turkish and Indian.
Ease of homemade preparation
Kefir: simple
Making kefir at home is relatively easy. It involves adding kefir grains to milk and allowing it to ferment at room temperature. The process is simple and doesn't require much equipment.
Yoghurt: can be tricky
Making yoghurt at home is a bit more involved, generally requiring a yoghurt maker or the ability to control fermentation temperature. It can be made using a starter culture or existing yoghurt, but it can be tricky process to master as I have experienced!
Kefir vs yoghurt: which is better?
Both kefir and yoghurt offer nutrition and gut health benefits. However, the diversity and number of microbes in kefir make it a better probiotic, and it’s lower levels of lactose make it more digestible. And on top of this, it is easier to make at home!
While kefir can’t replace yoghurt in all circumstances, particularly in cooking, it gets our vote for being better for health.
Our favourite gut health products in the UK
Symprove probiotic - developed by scientists, supported by clinical studies and superior at colonising you gut. The best and most evidenced probiotic in our opinion. Use discount code HELLOGUT50 for 50% off the first three months
Hellopath gut health tests - the UK’s most comprehensive gut health test. It tests over 100 biomarkers, checks your digestion and immune response, analyses leaky gut and provides a report on your microbiome
M&S x ZOE gut shot - this is both the best kefir and best gut shot in the UK in our opinion. It has 14 different strains of beneficial bacteria, prebiotics, fruits, ginger and lemon - all which have been shown to be good for the gut.
Your author
This article was written by Travis - learn more about me!
Or learn more about the basics of gut health.
Recommended articles
