Does Kefir Help with Weight Loss?

Does Kefir Help with Weight Loss?

Probiotics have come into their own in recent years as our understanding of the importance of gut health to overall wellbeing has matured. The so-called "second brain" found our GI tract is linked to not only digestive health, but overall physiological processes and even mood and psychological wellness.

There is also a growing scientific consensus that probiotics can aid in weight loss.  Having recently embarked on my own weight loss crusade, I decided to put the theory to the test: will adding a supercharged dose of probiotic kefir to my daily routine accelerate weight loss?

The results were, to me, quite shocking. Read on.

Disclaimer: consult with a physician prior to starting any new weight loss, supplement or diet plan.


Largely locked at home during Covid and after receiving the news that I was going to be a dad, I decided early in 2021 to get serious about losing the excess weight I had accumulated since my mid-20s.

Then 34 years old and inexorably closing in on 300 lbs with a growing list of health issues--e.g. high blood pressure, gout, chronic low energy--it was clearly time for a change. But where to begin?

After doing some fresh research, I developed a weight loss framework, and a plan that I thought best matched my psychological make-up.

For starters, I found it helpful to define an optimization problem (yes, I am, at heart, a hopeless nerd):

Weight loss = daily caloric deficit + time

While much effort is spent on the first factor (how to engineer a daily caloric deficit), I do not think sufficient emphasis is placed on the second, and arguably, more important consideration: sustainability.

Anyone can devise a diet wherein fewer calories are consumed than burned.  No carb, keto, paleo, or just straight up fasting.  Any of these can work to sufficiently reduce caloric intake. 

But as everyone intuitively knows, staying on-plan for months or years is where things breakdown.

Diet & Exercise

Long story short, I ended up implementing and sticking with Tim Ferriss's Slow Carb Diet, also found in his 4 Hour Body book.  The plan is essentially:

  • no "white" or starchy carbs
  • no fruit or sugar-added foods
  • one "cheat" day a week to go crazy and have whatever you want.

Over time, I layered in exercise as well:

  • three days a week of jogging for approx. forty minutes
  • two days a week of a simple twenty-minute kettlebell circuit.

And it went pretty well:

Weight Loss Slow Carb Diet


After two months, I was down ~17 lbs and losing at a fairly consistent clip of a pound a week.

(Note in the above chart, I've depicted my trailing 7-day average weight, to smooth out the daily fluctuations and clarify the trend).

While these results were encouraging, I felt I could be doing more.

At this point, I added the third leg to the stool: a supercharge of probiotics in the form of daily homemade kefir.

Calling in the Cavalry: Probiotic Kefir for Weight Loss

Now, changing nothing else with my diet or exercise plan, I started adding homemade, whole-milk kefir to my daily routine (drinking this first thing in the morning before breakfast).

As "real" traditionally crafted kefir (as opposed to the watered down, store-bought variety) can be quite potent, I started with quarter cup per day and worked up to a full cup per day by the end of the first week.

Probiotic Kefir for Weight Loss


In the following 30 days, I lost another 11 lbs, and in effect, tripled my rate of weight loss--from one pound a week to three pounds per week--simply by adding a daily dose of kefir.

If I hadn't experienced this dramatic shift myself, I would scarcely believe it, but these numbers are real and so has been the impact on my health.

Questions / comments? Shoot us a line.


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