The Hidden Link Between Your Gut and Your Waistline

This may seem totally obvious once you read the results of the latest Stanford study but you might also wonder why it took so long!

The reason you are not losing weight while dieting is because... your gut microbiome has a say in the matter. And everyone's biome is different so... the diet that works for one person might be completely useless for the next person. Mind blowing, yes?! Yep. My mind was blown.

Low-Fat vs. Low-Carb

They put some people on low-fat diets and some people on low-carb diets. People who strictly followed either diet lost weight during the short-term (first 6 months). OK. Fine. But here's the kicker... The people who maintained the weight loss for a year ate the SAME number of calories as those who regained weight or who didn't lose weight during the second six months. Well, that sucks. Can you imagine watching your friend eat the same amount of calories as you and they are losing weight while you are gaining weight or plateauing?

That's because some people lost weight better on low-fat diets while others lost weight better on low-carb diets. Why the difference? Why do some people lose weight while others gain weight? Well... turns out it depends on several biomarkers: gut microbiome, proteins made by the body and the levels of exhaled carbon dioxide (CO2). Using those biomarkers, researchers could actually predict, at the start of the study, how successful someone would be at losing weight and keeping it off long-term.

The researchers tracked 609 people over a year. How much they ate, what they ate (mostly healthy minimally processed foods) and how much they exercised. What they found was this... just cutting calories or exercising more was NOT enough to sustain weight loss over a year.

Which makes zero sense... because for years we've been told that weight loss is 80/20 - 80% has to do with what you eat and 20% has to do with exercise. Nope, that little rule of thumb is out the window.

Why some Lose Weight while Others Gain Weight

One of the key pieces of the puzzle was the level of exhaled carbon dioxide. The researchers measured the ratio of how much oxygen is inhaled to how much carbon dioxide is exhaled. They used this as a proxy to determine if the body's primary fuel was carbs or fats. A lower ratio means the body burns fat better... while a higher ratio means it burns carbs better. So people who started the study with a higher ratio lost more weight on a low-carb diet because their body burns carbs better.

Think about it... there you are... munching away on your Keto diet because that's what your workout coach recommended. And he's ripped with muscles everywhere and not an ounce of fat on him. You go to town with the Keto, eating all sorts of high fat foods - bacon, cheese, beef, coconut fat, etc. And you avoid carbs like the plague - no potatoes, no noodles, no beans, no pizza. Let's do it!!!

And yet... after a year of eating on Keto you haven't lost the weight... in fact you've put on MORE weight. Why?? It's because your body burns carbs better. And you've been feeding your body the wrong fuel. It's not a lack of willpower. It's the wrong fuel.

If your body prefers carbs, and you're feeding it fats (or vice versa)... your body is not going to be able to metabolize those calories very well... or burn them off. Makes sense. So much sense.

And it all comes down to the your gut microbiome. Do they like to eat carbs? Or do they prefer fats? Can you just imagine a future in which you go to your doctor, they do some tests and hand you a personalized weight-loss or healthy eating plan? Whoa... 

Which begs the question... how do we find out  which is best for u!!?? Well... here's the thing. There isn't a test right now that will easily tell us what sort of gut microbiome we have rumbling around in our insides. Although... some fitness centres or wellness centres will do the respiratory quotient test for you ($$). It measures the ratio of inhaled oxygen to exhaled carbon dioxide.

In the Meantime...

Sooooo... in the meantime... this is what the researchers recommend:

• eat mostly unprocessed foods (real food - not processed "food")
• eat foods low in refined flours (I'm looking at your bread and noodles)
• eat foods low in refined sugar (sigh... brownies!!)
• eat healthy fats like avocados, olives and nuts (not bacon! or coconut oil!)
• get enough fibre from whole grains and beans (even on a low-fat diet - not all carbs are bad)
• learn to cook and rely less on highly processed foods

Well... that makes sense. It's the same advice as always... eat real food, mostly plants, and not too much. Stay away from processed "food". Stay away from sugar and refined flours. And if you're sticking to some diet plan and not losing weight... or actually putting on weight... maybe low-fat or low-carb is not for you.

Now the researchers also acknowledge that some ethnic and racial groups were underrepresented. Which makes me wonder... are some diets better for some ethnic groups than others? Based on different gut microbiomes? And what about men vs. women? Does that make a difference?

The bottom line is this... the diet that works for one person is not necessarily going to work for you. And yes... while you might be able to lose weight short-term on that Keto diet... if it's not the diet for your guy microbiome, it won't work long-term. That is out of your control.

Once again... back to small steps. It's those small daily choices that we make that help us along.

Read More

SciTech - Summary of the Stanford Study

CTV News - Stanford study identifies what influences weight loss the most

Cell Reports Medicine - the full Stanford report

Intake Health - info on the Respiratory Quotient (ratio of inhaled oxygen to exhaled carbon dioxide)