How To Fix Your Gut Health & Digestion



This article ties together the four-part fat loss series. To make your fat loss as quick and painless as possible, I highly recommend following this up by reading:


Are you always…




Suffering from indigestion?

Struggling to eat certain foods?

...It can all (potentially) be tied back to your gut.

This is exactly why “gut health” has become a hot topic in the fitness industry over the last few years.

Your gut health has potential implications for TONS of different areas of your life - body fat, susceptibility to autoimmune diseases, fertility, hormones… the list goes on and on.

See, your gut is full of trillions of bacteria microorganisms - the “gut microbiome”.

All these microorganisms make up a whole ecosystem in your belly. This ecosystem can be helpful (doing things like improving digestion, or strengthening the immune system) or harmful (doing things like causing bloating, gas, and diarrhea) depending on the balance of different bacteria.

Truly, there’s lots of interesting stuff going on here...

→ We have fat mice in the lab getting lean by eating the poop of thin mice, allowing them to repopulate their guts with “thin” bacteria. (1)

→ We know that our bacterial cells outnumber human cells 10:1.

→  80% of our immune system is based in the gut

→ 95% of  our Serotonin is stored in the gut

→ 50% of our Dopamine is made in the gut

So yeah. Focusing on gut health seems to be important, for everything from getting lean & strong, to your overall sense of happiness and well-being.

But Wait...

But, hold up. Before you ask your super lean friend for a poop sample (I know you were thinking it too)...

We don't really know what's going on here.

There are TONS of products being sold to capitalize on the gut health hype - prebiotics, probiotics, kombucha, and the like.

But the reality is, scientists don’t really know what is going on here. Study of the gut & the gut microbiome is a very new field.

When it comes to most gut health supplements, to quote Dr. Gabrielle Fundaro:

“...supplement consumers should keep in mind that they are colonized with trillions of bacteria, so taking a pill with one million of one strain of bacteria is like using an eye dropper to add water to the ocean. The most effective supplements are multi-strain with multiple billions of bacteria (or CFU, which stands for colony-forming units). Also, what they find on the shelf may not actually contain the numbers of bacteria stated on the label.”

Basically, a good probiotic supplement will provide billions of CFU’s and cost around $50/month, and cheaper products that don’t provide CFU’s in the billions aren’t doing much.

And even then, it’s very hard to know if you’re getting the bacteria you specifically need via supplement.

So really, as far as gut health supplements go it's hard to identify what and how much we need to supplement in order to improve things.

That said, if you’re struggling with bloating, constipation, brain fog, etc. read on. Because most of what we come across as coaches can be remedied by some basic lifestyle changes.

What's Going On In The Digestive System?

So basically, we’re talking about improving your gut and digestive system’s ability to properly break down the food you eat into energy, without all the nasty side-effects we talked about earlier.

As un-sexy as it sounds, improving your digestion is one of the best things you can do for your gut health. The ability to properly digest food is VERY important to your gut health and your ability to build a lean, strong body.

So why wouldn’t you be able to properly digest food?


Major digestive issues can stem from stress hormones interacting with salivary glands, stomach, intestines, etc.

See, digestion start before food even hits your mouth, with the cephalic phase - basically, the sight, smell, or thought of yummy food actually causes your body to prep the gastrointestinal tract for a meal.

You salivate & increase the amount of the digestive enzyme Amylase in the mouth, gastric juice is produced in your stomach, and lots of other not that interesting stuff happens.

BUT, the point is - all of these juices & enzymes really help digestion, because they break down the food you consume, and help your body turn it into useable nutrients.

When you’re stressed (or just eating in a big rush), the signals that induce the  Cephalic Phase get interrupted.This is where stress STARTS to disrupt what’s going on in the stomach.

Basically, your stomach has been “switched off” to a degree - you’re downregulating gastric juice production. This means you won’t be able to break down food as effectively, and digest all the nutrients you just ate.

Now, you have all of this food in your stomach, but not enough digestive enzymes & gastric juices there to digest it. You’re not digesting foods NEARLY as fast as should - so you get stopped up, you get reflux, food sits in your stomach & you get bloated.

So often the root of gut issues, is doing a better job of managing stress - especially around meals.


Now, before you prescribe yourself hours of meditation & yoga daily...

Realize that an inefficient aerobic system can ALSO be a big problem here.

If you have a  weak aerobic system, your heart rate will likely be elevated more often than not - this in turn means that stress hormones will ALSO always be elevated - and just like above, the extra stress means your digestion will suffer.

So, you might not need more breath work, you might just need more cardio ;)

Intestinal Permeability Or "Leaky Gut"

So now that you understand the basics of many issues at the digestive level, let's get a bit deeper into some more popular gut issues.

In simplest terms - when you eat food, it eventually makes its way to your small intestine.

There, your food (which is HOPEFULLY no longer recognizable from what entered your mouth) comes into contact with Villi.

Villi is basically a bunch of tiny-ass finger looking things that line the wall of your small intestine. These mini-fingers have tiny cells that take in the amino acids, vitamins, minerals, etc. from your foods and drop them into your bloodstream, where they’re shipped off to become GAINS!

So in the ideal world:

1. You eat food

2. It eventually makes its way to your small intestine, where it’s fully digested

3. All those creepy lil’ fingers in your small intestine drop the nutrients from said food into your blood stream, where it's delivered throughout your body for various functions.

But unfortunately, things don’t always go as planned.

We can get issues of “increased permeability” or as you’ve probably heard it called... “leaky gut”.

Your mucosal membrane is what protects the integrity of the villi cells, and keeps stuff from leaking through. In a case of intestinal permeability, this membrane has been eaten away. The spaces between the Villi cells increase, and food starts to slip through the wall of your gut into the bloodstream without being properly digested or absorbed.

Where Does Intestinal Permeability Come From & Why Does It Matter?

→ Gut bacteria.

So remember all of that bacteria in your gut we were talking about earlier?

Much of it lives in your large intestine. Like all living things, this bacteria needs to be FED to stay  alive. When there’s a lack of food available in the large intestine, the bacteria there will swim up to the small intestine, searching for a fuel source.

When it reaches your small intestine, this bacteria sees the mucosal membrane as a tasty fuel source, and starts eating away at - this leads to increased intestinal permeability.


So one of the BEST ways to prevent your gut bacteria from eating away at your mucosal membrane, is simply eat your fruits & veggies.

This can also happen as a response to stress. Corticotropin releasing factor (CRF), a hormone involved in the stress response, triggers increases in intestinal permeability. (2)(3)

→ Lectins (a protein) & Phytates (the storage form of phosphorus) found in foods like wheat, barley, rice, beans, nuts, legumes, seeds, and soy can eat away at the mucosal membrane FOR SOME INDIVIDUALS. (NOTE: This is NOT saying that everyone should avoid these foods, or even that eliminating them is where you should start if you have gut issues.)

Why Does Intestinal Permeability Matter?

When undigested foods enter your bloodstream, your immune system sees a foreign invader and ATTACKS. Your whole immune system is put on red alert, which can create an “auto-immune response” to specific foods.

This can create situations where people can’t eat specific foods anymore, that they USED TO not have any issues with.

Intestinal permeability also can lead to endotoxins in the blood steam - endotoxins are very inflammatory substances, and can lead to a lot of inflammation.

Fixing Your Gut 101 - The Solution

First, if you're experiencing serious gut issues, see a healthcare professional. From here, addressing the root of the problem this should generally be very lifestyle-focused, NOT supplement-focused.


→ Manage your eating environment. Do your best to maintain a stress free eating environment. Don’t eat where you work - focus on your food. If you’re thinking about work, you'll likely be more stressed, which takes away from your ability to digest & relax.

→ Chew your food. Focus on chewing your food to the point where it’s partially liquefied before swallowing. It also helps to SLOW DOWN, by setting your fork down between bites.

→ Chrononutrition. Your circadian rhythm plays a big role in how your body reacts to ingesting food, and WHAT it does with said nutrients. It makes sense to follow the guidelines established in THIS BLOG.

→ Keep the 5-10 minutes that bookend meals as stress-free & relaxed as possible. But, for most people this is more realistically something like 5-10 deep breaths before eating. If you're crazy busy, and don't have 5-10 minutes to wind down around meals, just try box breathing. 5 sec inhale, hold for 5 sec, 5 sec exhale. Repeat x5-10.

→ Train your aerobic system. The aerobic system is an oft-neglected part of health and managing stress - this is exactly why my online clients always have some aerobic work programmed in. It's just too important to ignore.

→ Focus on managing life stress. Implementing tools like meditation, breath work, journaling, and time away from screens.


→ Eat lots of high-fiber fruits & veggies. This is essential to feeding your gut bacteria, and keeping them from eating away at your mucosal membrane. This, stress management, and aerobic work are the BIGGEST pieces many are missing.

→ Work in foods you enjoy. Remember the cephalic phase? Being excited about your food helps your body better digest said food - which really gives merit to focusing on enjoying your food.

 → Intermittent fasting and/or spending time in a calorie deficit can potentially help. The migratory motor complex (think: your stomach's housekeeper. It sweeps everything out, and really helps your stomach clean out all the junk.) happens after food has been digested. This won’t happen if you’re constantly eating.

→ If none of the above helps, it could also make sense to try an elimination protocol. Here, you pull out common irritants like lectins, phytates, nightshades, and more in an attempt to recognize which foods specifically are causing issues. CLICK HERE to learn more about how to run an elimination protocol.

Gut health is a complex topic.

But, for most it has a relatively simple solution - eat lots of whole foods, manage stress, be present at meal-times, and potentially get a bit more cardio in.

These are the exact principles we focus on when you start online coaching. Not only are they the prescription for a healthy gut, but for building your leanest, strongest self.

For accountability and expert guidance, CLICK HERE to apply for online coaching.

About The Author

Jeremiah Bair is a certified nutrition coach, strength coach, and owner of the online coaching business Bairfit. Check out his Instagram and Podcast for more applicable strategies for building your leanest, strongest, and most confident self.

1. Why Dieting Is So Hard (And How To Make It Easier)

2. Why Fat Loss Stalls (And What To Do)

3. Strategies To Make Dieting Suck Less



You're here because you want to lose body fat.



To lose body fat, you need to be in a calorie deficit.




Energy (calories) consumed < Energy (calories) burned = Fat loss



Or, as you've probably heard it: Calories in > calories out = fat loss



Basically, if you’re eating fewer calories than you’re burning in a day, you’re in a calorie deficit.



Every diet in existence causes fat loss by, in some way, creating a calorie deficit.



Sooo, you’re saying I lose fat by eating less, and only by eating less?



Yep. Groundbreaking right?



Generally, creating a calorie deficit of ~3,500 calories leads to ~1 LB fat loss.



Therefore, eating 500 calories below your maintenance calorie intake every day for 7 days, should lead to about a pound of fat loss. (500 x 7 = 3,500)



As you diet, you're taking in less energy (calories). Therefore, you'll feel more lethargic, and likely expend less energy. This reduces the "calories out" (calories burned) side of the equation changes.



For this reason, fat loss often stalls- despite eating at what you initially calculated as a deficit. More on that here: Why Fat Loss Stalls (And What To Do)



You'll often hear people blame "Slow metabolism" or "out of balance hormones" for their inability to lose weight.



These are rarely the issue. I talk about these myths more in: Why Fat Loss Stalls (And What To Do)  (tl;dr: We suck at estimating our calorie intake, and are usually eating more than we think. Our bodies also burn fewer calories as they get smaller.)



The truth is... 99.9% of the time, if you can't lose fat, you're simply eating too much.



Some diets are believed to have magical, mysterious fat loss properties. Especially intermittent fasting and keto.



This is not the case. All diets are simply different ways of getting you to eat less, and therefore creating a calorie deficit. Not a single diet exists that allows you to lose weight without creating a calorie deficit.





How Do I Create A Calorie Deficit?

I highly recommend you use a calorie tracking app. MyFitnessPal is my personal favorite. More on different ways of measuring calorie intake in: 
Strategies To Make Dieting Suck Less



1. You need to know what your calorie intake should be.

Use this calculator if you don’t know already:

Now multiply this number by .85 (for less aggressive fat loss) OR .8 (for more aggressive fat loss).

Gerald- a 200 lb man, has a maintenance intake of 2,800 kcal per day.

To determine starting cutting calories, he simply multiplies his maintenance intake by .85

2,800 X .85 = 2,380

Gerald's cutting intake is 2,380 kcal per day.




Next, you need to figure out how to divy up these calories by macronutrient.

The three macronutrients (macros) are:

-Protein: 1 gram of protein contains ~4 kcal

-Carbohydrates: 1 gram of carbohydrate contains ~4 kcal

-Fat: 1 gram of fat contains ~9 kcal


2. Calculate protein intake.

When you’re cutting, adequate protein intake is a must.



Hitting your protein requirements means you're more likely to build/preserve muscle (depending on how long you've been training).


Aim for 1 gram of protein per pound of body weight, daily.

To calculate: multiply your bodyweight X 1. That's how many grams of protein you'll be eating.


200 lb Gerald needs 200 grams of protein.

200 X 1 = 200.

800 of Gerald's 2,380 kcal/day will come from protein. (Remember, protein contains 4 kcal per gram)

200 X 4 = 800 kcal

3. Calculate fat intake.

For optimal hormonal function and health, at least 15-20% of your daily calories should come from fat.


Protein intake should remain constant, but you’re free to adjust fat and carb intake to preference.



Most feel and perform better with a higher carb intake. So keeping fat lower (~20% of daily kcal) generally makes sense.


Back to Gerald, with a goal intake of 2,380 kcal.

2,380 x .20 = 476

Gerald will be eating 476 kcal of fat per day.

To determine how many grams of fat this is, simply divide by 9. (Remember, fat contains 9 kcals per gram.)

476/9 = 53 (Well, 52.89)

Gerald will be eating 86 grams of fat per day.

4. Calculate carb intake.

All that's left to do is fill the your remaining calories with carbs.


Gerald has a goal intake of 2,380 kcal per day.


Subtract the 800 kcal coming from protein.

2,380 - 800 = 1,580 kcal

Subtract the 476 kcal coming from fat.

1,580 - 476 = 1,104 kcal

Gerald has 1,104 kcal remaining to fill with carbs.

To determine how many grams of carbs to eat, simply divide by 4. (Remember, carbs contain 4 kcal per gram.)

1,104/4 = 276

Gerald will be eating 276 grams of carbs per day.

Gerald's final macros:

Total calories: 3,086

Protein: 200 g | 800 kcal

Fat: 53 g | 477 kcal

Carbs: 276 g | 1,104 kcal



How Fast Should I Lose Weight?


Unless you're new to the gym, and already pretty low body fat, you're going to lose a good chunk of weight in the process of getting lean.



For most, the ideal speed of weight loss when cutting is .5-1% of body weight per week.



Go much slower than this- you won't see see much progress on a weekly basis. Your cut will drag on. You'll get sick of dieting.



Go much faster than this- you'll feel constant fatigue, mental performance will suffer, and you're at a higher risk of muscle loss.



Again, a general recommendation. But for most, .5-1% of bodyweight per week is easiest to adhere to.




How Do I Measure Progress?

As mentioned, the scale is a good way to measure progress. However, on a weekly basis, scale weight can fluctuate pretty wildly, due to things like water retention from higher sodium intake, stress, and digestive issues.



Especially for women, hormonal fluctuations mean looking at weekly scale changes isn't always the most accurate measure of progress.



For the scale- Don't make adjustments on weekly changes. Look at the trend over multiple weeks-monthly changes.



You're still aiming to lose .5-1% of bodyweight loss per week, just don't worry if this doesn't show up on the scale every week.



However, the monthly trend should show 2-4% of total bodyweight lost.



Weigh yourself at least three times per week. First thing in the morning, before eating or drinking, and after using the bathroom. Having multiple weigh-ins per week will give you a much better picture of where your weight actually is at.



Body measurements- To accurately gauge progress, take the following measurement once per week, at the same time you weigh in. For accuracy, measure in centimeters with a soft tape measure.



1. Chest. Take a circumference measurement, with the tape at the level of the nipples.



2. Navel. Take a circumference measurement of your torso with the tape 2 cm above the navel.



3. Hips. Take a circumference measurement around the broadest part of the hips.



4. Thigh. Take a circumference measurement around the broadest part of the right thigh.



Make sure to record these along with weekly weight changes. If weight loss has stalled, but measurements are decreasing, or vice versa, stay the course. 



When both weight loss and measurements stall for 2+ weeks, it's likely time to implement a change. Read this article on how to make the necessary adjustments: Why Fat Loss Stalls (And What To Do)



It's common knowledge that a calorie deficit leads to fat loss. So why do so many people struggle losing fat?



While it ultimately come down to...


calories in < calories out = fat loss


...there's a lot of other factors that make sticking to a diet much harder. Learn how to deal with those here: Why Dieting Is So Hard (And How To Make It Easier)



Finally, people often just choose a diet structure that doesn't fit their lifestyle. Finding a diet you can adhere to is key to sustainable results. I wrote a guide on the different diet structures I use with clients here:Strategies To Make Dieting Suck Less



If you have questions about any of this- shoot me an email at I'm happy to help!

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