The science is still out on whether kefir or any other probiotic rich food has a direct effect on our weight. Evidence on probiotics and weight loss is conflicting. Some studies suggest that certain lactobacillus strains, or such as those found in kefir and other fermented dairy products like yoghurt and cheese are associated with weight changes, but other studies contradict this evidence.
There have been a number of promising experiments, however, suggesting that probiotics and metabolism have a complicated relationship that we don’t yet fully understand. A 2008 study found that probiotics have a tangible effect on metabolism although we are not sure exactly what this effect is.
One promising study found that kefir prevented additional fat accumulation in overweight mice and the scientists concluded that it has the potential to prevent obesity.
Other scientists found that probiotics have an effect on the metabolisation of bile acids in the liver, which works to emulsify fats. According to the researchers, the finding show that beneficial bacteria could change how much fat the body is able to absorb from food. The two most effective strains of bacteria for losing weight are thought to be Lactobacillus and/or Bifidobacterium, both of which are found in kefir.
Another team of scientific researchers discovered a genetic link between weight and microbial balance in both mice and humans. Overweight subjects had a completely different bacteria composition than slim subjects, and but when bacteria were transferred from the gut of overweight subjects into slim subjects, the slim subjects started to gain weight.
This lead the scientists to believe that not only do gut bacteria influence our metabolism, but also that microbes have a complex relationship with human hosts than could even extend to the manipulation of our weight related genes. Subjects started to lose weight after supplied with probiotics over a few weeks.
The researchers also found our gut bacteria can “determine the efficiency with which calories can be harvested from the diet.” While efficiency in harvesting calories form food is a huge advantage when you’re starving, it’s not so great in today’s modern age when we are surrounded by calorie-dense foods and many of us lead physically sedentary lives. It looks like transforming your gut bacteria can actually cause you to extract fewer calories from the same food item.
Probiotics have also been linked to health issues that can arise from being overweight, including improved glucose and fat metabolism, cholesterol, high blood pressure, improved insulin sensitivity, type 2 diabetes, and the calming of chronic systemic inflammation.
In addition, kefir cultures have the ability to assimilate cholesterol in milk, reducing the amount of fat as well as the eating the sugars such as the common irritant lactose.
Emotional eaters should add kefir to their diets, as probiotics have been found to affect mood, easing depression, irritability and overall mental health than can cause many to turn toward unhealthy or dietary choices like excessive eating.
But probiotics aren’t the only component of kefir that may help with weight loss. Kefir is also a source of tryptophan, an amino acid that has a calming effect on the nervous system (similarly to turkey, which is known to send people off to sleep). It can also help to alleviate insomnia which can have a real effect on mood and make you more likely to choose fatty convenience foods out of exhaustion.
Kefir is generally a dairy product (although you can also make vegan kefir from coconut milk or even sugared water) and there is research to show that consuming diary can help to shed the pounds. Dairy contains both protein and calcium, each of which have been linked to weight loss.
Whole dairy products provide a synergistic combination of these two nutrients, although it’s not clear exactly how they work in weight loss and maintenance. While diary is a common thing dieters cut out in order to lose weight, some studies have found that a few servings per week can help to shed the pounds; it’s thought this is because the calcium in milk promotes fat burning rather than fat storage.
Kefir has around 11 grams of protein per cup, making it significantly higher in the nutrient than yoghurt, although kefir is also higher in calories than plain yoghurt. Protein is known to provide a feeling of satiety, making you feel full for longer than carbohydrates that tend to provide a quick burst of energy which burns off quickly, leaving you hungry sooner. It’s best to avoid flavoured or overly processed kefir, as these often contain additional sugar, which is no good for your waistline or internal health.
Another substance in dairy linked to weight loss is linoelic acid, a fatty acid. One experiment found that linoleic acid supplementation brought down the weight of obese participants over a six-month period and prevented weight gain during the holiday season.
Simply adding kefir to an unhealthy diet will not be enough to lose significant amounts weight, but it works on multiple levels to support you in your weight loss journey and help you on the path to your health goals.