How your microbes can help you to lose weight
Is it as simple as calories in versus calories out?
And whoever is overweight and not losing fat is just not trying hard enough?
No, not really!
A study from the fifties showed us that the food composition matters even more than the calorie count.
In this study, scientist put patients on a diet in which the daily intake was kept constant at 1000 calories a day and 90 % of it was provided by either fat, protein, or carbohydrate.
Here are the results:
The patients who consumed 1000 calories from a 90% fat diet showed 0.4kg of weight loss per day,
And a diet of 90% protein diet showed a similar loss with 0.3kg per day
But the patients who consumed 90% of their calories from carbohydrate actually gained on average 100 grams per day! Despite the high caloric deficit!
The results of this study debunk the importance of focusing on calories in and calories out when trying to lose weight, so we can forget about calories for the moment.
However, food composition is not the only factor that should be taken into consideration:
In Canada, students enrolled in a study that isolated them from the rest of the world for 120 days. The participants of the study were only allowed to eat, sleep, watch tv, and read
This must sound like a dream to most students. But there was a caveat:
The students were restricted from all physical activity and were over-fed 1000 extra calories.
After the 120 days, the students gained on average 8.1kg of body weight, which is not very surprising.
What was surprising, however, was the range of weight gain.
While some students only gained 4.3kg, others gained up to three times more weight.
The results of this study show that there is something more than just the macronutrient composition. One could argue that it is all genetics that makes the big differences here. But consider the following: The human DNA is 99.9% similar between individuals.
What I am getting at is that there is actually a third factor that, seems to play an important role. A factor that has been overlooked and has never been taken into consideration.
The factor I am talking about is the inhabitants of your gut. Your Microbiome
With 100 trillion microbes in your gut, there are about 10 times as many microbial cells in the body as there are human cells.
With an estimate of more than 10,000 different species of microbes, they provide a metabolic capacity which exceeds the liver by a factor of 100.
And while the human DNA is very similar between individuals, there are huge differences in the composition of the microbiome between different people. This might explain while somebody becomes overweight or develops a disease but somebody with the same DNA stays perfectly healthy.
Now imagine the following scenario: Two genetically identical people decide to lose weight by going on a diet. The only difference between the two twins is that one of them was treated for 10 days with an antibiotic due to an infection, which kills big parts of the microbiome. So, will the twins lose weight equally?
Based on the evidence found by various studies, absolutely not.
In fact, there is no shortage of studies, showing how antibiotic usage leads to abnormal weight gain.
One reason antibiotics are used so much in livestock is that at some point farmers discovered that by using antibiotics the animals grew fatter.
Just using low concentrations of antibiotics is enough to alter the composition of gut bacteria and promote fat gain!
2. The obese microbiome
But even if you’ve never taken antibiotics, your microbiome could still be promoting weight gain.
Researchers found that the microbiome of overweight people is already very different compared to lean people, regardless if they take any medication. Scientist even invented a special name for it: “The obese Microbiome”
To exclude the factor of genes, researchers analyzed the microbiome of twins.
These twins were quite physically different from each other, one twin was lean while the other one was obese. After taking a look at each twin’s individual microbiome, they found that their microbiomes were just as different as their physical appearance was.
The obese individuals had a far less diverse microbiome. The diversity of our microbiome is critical for our health and a less diverse microbiome has been associated with many diseases.
They found that “obesity was associated with phylum-level changes and a reduced microbiota diversity.”
Let me briefly explain what the term “phylum changes” actually means.
A phylum is a group. And with regard to our microbes, we can group certain classes and types of bacteria into distinct phylums.
Another group of researchers looked into the phylums of gut bacteria found in lean and obese twins. They found that the obese twins had 20% more of one group of bacteria called Firmicutes and nearly 90% less of another group called of Bakteröiditis.
These two bacterial groups are the two most abundant phylums in our microbiome, which makeup up to 90% of our microbiome.
Researchers use the ratio of these two groups as a biomarker for obesity. The higher the ratio of Firmicutes to Bacteroidetes, the higher the risk of becoming overweight.
The study also questions if the ratio of firmicutes to bacteroidetes was set in stone. The obese volunteers were set on a diet for one year and their percentage of bacteroidetes nicely increased while they lost weight. This shows that the microbiome diversity is apt to change with alterations in diet.
3. Transfer of obese mice microbes
The next study is a great example of how the human microbiome can have a huge influence your waistline!
Researchers sucked microbes from the guts of lean mice and obese ones. Then, they injected the microbes into the intestines of animals whose own microbes were deleted due to sterile caging.
The mice injected with the 'obese' microbes gained roughly double the quantity of fat than those that received the 'lean' microbes!
Another paper published in the Journal Science went one step further with this research by extracting the microbiome from human twins, one obese twin, and one lean twin, and then transferred the microbes into different sterile mice.
I guess by now you won’t be surprised hear the results of the study showed the mice who received the obese microbiome gained more body mass, especially fat, than the mice with the lean microbiome.
Let me cite the chief editor of the renowned science journal, Nature, here:
“Fat people harbor fat microbes.”
“The obese are often blamed for their own corpulence. But perhaps, just perhaps, some of the blame should be placed on another type of organism entirely: bacteria.”
Here is another example of how easy you can improve your odds:
In 2015 scientist gave a group of volunteers 21 grams of fiber extra per day or just a placebo.
After just 21 days the abundance of bacteroidetes increase by 13% in the group that received the fiber.
With this knowledge, one might consider that the first step of a diet should be to reset our microbiome!
For the start, it would be the best to focus on less processed food as they contain naturally more fiber. Maybe even include some probiotic food like kimchi or sauerkraut - or even take some probiotic supplements to get a fast start.
For my last diet, it certainly helped me a lot to focus on a diet with high fiber intake and good fats - and I never lost fat so easily while staying mentally sharp.
Subscribe this channel and check out our website or facebook page if you want to receive interesting studies and helpful tips around the topics Health and Microbiome!
Thanks for watching!