functional nutrition

Sibo Doctor Approved
Alyssa Simpson RD, CDE, CLT
Alyssa Simpson

(602) 422-9800

Sibo Doctor Approved
certified gastrointestinal nutritionist
Sibo Doctor Approved
certified gastrointestinal nutritionist

How digestion really works. Spoiler alert: it doesn’t start in your stomach.

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They say ‘you are what you eat’. But that’s not entirely accurate. The truth is that you are what you absorb from your food. And the only way you can effectively absorb the nutrients in your food is to digest it properly.

Unless you have digestive problems, you probably don’t think much about what happens to your food after you eat it. You chew. You swallow. And then you’re not hungry anymore.

But if you’re hanging out on my website, I’m guessing that your digestion isn’t running as smoothly as you’d like. Whether you’ve been diagnosed with IBS or are just struggling with troublesome digestive symptoms like diarrhea, constipation, bloating, gas, stomach pain, or some combination, you’re probably looking for answers.

Well, I’ve got some good news for you. It is totally possible to improve your symptoms naturally. There are things you can do TODAY that will get you on the road to feeling better. And it doesn’t even require a trip to the pharmacy.

The key is digestion. Now don’t get me wrong. Improving your digestion isn’t going to address the root cause and all the issues involved with complex conditions like IBS. But it’s a great place to start.

So for the next few weeks, we’re going to be diving into the digestive process. I’ll explain what is actually happening to your food inside your body. And each week I’ll include some practical tips for things you can do to improve your digestion right away.

Digestion is a North to South Process

When you think of digestion, you may imagine that it happens in your stomach. And that’s true. But there’s a lot more to your digestion than that. Digestion is a complex process that starts in your brain and goes all the way down to the end of your large intestine.

And anything that goes wrong with your digestion at the top affects the rest of the process. So we’re going to start with the brain and work our way down…

Digestion Begins in the Brain

Think of the last time you were really hungry and walked into a restaurant or kitchen where a meal was being prepared. What happened when you smelled the food? Maybe your stomach rumbled. Maybe your mouth started to water.

That’s no accident. From the moment your brain senses that food is coming, it prepares for the process of digestion. This is an important first step to the digestive process. Your body is best able to digest your food and absorb the nutrients when it’s revved up and ready.

You’ve probably heard of fight or flight mode. That’s when you are under physical or emotional stress and your brain switches your nervous system into a sympathetic state. When this happens, your body responds.

When your sympathetic nervous system is activated, it affects your:

Eyes — Your pupils dilate to improve your vision

Heart — Your heart rate increases to get more oxygen to your limbs

Lungs — Your airway muscles relax to increase oxygen delivery

Liver — Releases energy stores so your muscles can act quickly

Digestive Tract — Your digestion slows down so your body can divert all its energy to escaping from danger

In other words, you don’t want to be in fight or flight mode when you’re eating. Fight or flight mode is what you need when you’re in physical danger. You have increased energy and quicker response times. In order to accomplish this, your body will de-prioritize non-emergency functions like digestion.

This mechanism evolved when our ancestors were running away from wild animals. And it’s very useful for that. But our bodies don’t know the difference between being stressed because you’re being chased by a bear and being stressed because you have a deadline at work.

De-prioritizing digestion back then probably wasn’t as big of a deal as it is now. Our ancestors weren’t trying to eat while they were escaping grave danger. But I know that lots of people will eat at their desk while they’re working on meeting that deadline. And if you eat while your sympathetic nervous system is activated, you’re not going to digest your food well. This leads to malabsorption of nutrients and digestive problems.

In order to optimize your digestion, your nervous system needs to be in a parasympathetic state — also known as rest and digest.

When the parasympathetic nervous system is activated, everything slows down. Only then can your digestive system work properly.

When you are in rest or digest mode, several things happen that affect your digestion:

Saliva production increases — providing enzymes needed to begin the process of digestion.

Your intestines get ready to move food along — this movement is called peristalsis.

Your gallbladder releases bile — which helps digest fats.

You also need to be in a parasympathetic state to have a bowel movement. You can’t poop well when you’re stressed either. So how do you get into a parasympathetic state?

Better Digestion Tip #1: Get into rest and digest mode.

In order to activate your parasympathetic nervous system, you’re going to have to relax when it’s time to eat. And that means you may have to change some habits.

Avoid eating while you’re:

❌ Driving or walking

❌ Working

❌ Angry or stressed

When it’s time to eat, take a few minutes and prepare your brain — so your brain can prepare your digestion system:

✅ Sit down somewhere comfortable to eat — avoid eating at your desk if at all possible.

✅ Close your eyes and take a few deep breaths.

✅ Take a minute to appreciate your meal. Look at the colors, smell the aromas.

✅ While you’re eating, be mindful of your food. Avoid distractions and arguments during meals.

Taking a few minutes to do these simple things can help get you out of fight or flight mode and get your body ready to rest and digest.

Most people in our stressed-out world spend way too much time in a sympathetic state. This makes it not only harder to digest your food, but also to rest, repair tissues, fight off illness, and have the aforementioned bowel movements.

But there are a number of ways to destress and get back into a parasympathetic state:

? Breathwork — Take some long belly breaths. Or try a technique like the breathing box. Breathe in for a count of four, hold for four, breathe out for four, and hold for four. Repeat this a few times until you feel calmer.

? Mindful Meditation — You can find guided meditations on Youtube or in apps like Headspace or the Calm App.

? Stress-reduction techniques — This can be anything from gentle movement, to spending time outdoors, to doing something fun.

Digestion Continues in the Mouth

By the time your food reaches your stomach, it should already be well on the road to being broken down. And that happens in your mouth.

Your mouth is the site of both mechanical and chemical digestion:

Mechanical — When you chew your food, it gets broken down into tiny pieces that are easier for your stomach to process.

Chemical — The enzymes in your saliva (including amylase, protease, and lipase) begin the process of breaking down your food so the nutrient components can be released and absorbed by the body.

Better Digestion Tip #2: Chew Your Food

Your grandmother was right. You probably don’t chew your food thoroughly enough. Ideally, you should be chewing each bite about 30 times. By the time the food travels down your throat, it should be applesauce consistency.

Do you ever drink your meals? Yes, the blender does break down your smoothie into a liquid form. But your blender doesn’t have the benefit of salivary enzymes to start the process of chemical digestion. So when you eat a smoothie, it’s important to chew it a bit too. Yes, I’m totally serious. Chewing starts the chemical breakdown of food, and it also causes your brain to alert your digestive system that food is coming… and soon!

If you’re struggling with stomach or intestinal issues, improving your digestion is a great step toward feeling better. But if you’ve been diagnosed with IBS or SIBO, or if your digestive symptoms are interfering with your life, it’s probably time to get some personalized help. I’d be happy to talk with you about what’s going on and what can be done to get you feeling better.

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