If there was ever a call for "digestive health," this is it!
Yes, it's true. Your gut is considered your "second brain."
There is no denying it anymore.
And because of the new scientific discoveries about the vagus nerve, the enteric nervous system, and the amazing influence your gut microbes can have, it's no wonder what you eat feeds not only your body but can directly affect your brain.
I find it amazing (but not too surprising).
What exactly is the "gut-brain connection."
Well, it’s very complex, and to be honest, we’re still learning lots about it!
There seem to be multiple things working together. Things like:
●The vagus nerve that links the gut directly to the brain;●
●The “enteric nervous system” (A.K.A. “second brain) that helps the complex intricacies of digestion flow with little to no involvement from the actual brain;●
●The massive amount of neurotransmitters produced by the gut;●
●The huge part of the immune system that is in the gut, but can travel throughout the body; and,
●The interactions and messages sent by the gut microbes.
This is complex. And amazing, if you ask me.
I’ll briefly touch on these areas, and end off with a delicious recipe (of course!)
There is a nerve that runs directly from the gut to the brain.
And after reading this so far, you’ll probably get a sense of which direction 90% of the transmission is…
Not from your brain to your gut (which is what we used to think), but from your gut up to your brain!
The enteric nervous system and neurotransmitters
Would you believe me if I told you that the gut has more nerves than your spinal cord?
I knew you would!
And that's why it's referred to as the "second brain."
And, if you think about it, controlling the complex process of digestion (i.e. digestive enzymes, absorption of nutrients, the flow of food, etc.) should probably be done pretty "smartly"...don't you think?
And guess how these nerves speak to each other, and to other cells? By chemical messengers called "neurotransmitters."
In fact, many of the neurotransmitters that have a strong effect on our mood are made in the gut! e.g. a whopping 95% of serotonin is made in your gut, not in your brain!
The immune system of the gut
Because eating and drinking is a huge portal where disease-causing critters can get into your body, it makes total sense that much of our defense system would be located there too, right? Seventy-five percent of our immune system is in our gut!
And you know that the immune cells can move throughout the entire body and cause inflammation just about anywhere, right?
Well, if they’re “activated” by something in the gut, they can potentially wreak havoc anywhere in the body. Including the potential to cause inflammation in the brain.
Your friendly neighborhood gut residents. You have billions of those little guys happily living in your gut. And they do amazing things like help you digest certain foods, make certain vitamins, and even help regulate inflammation!
But more and more evidence is showing that changes in your gut microbiota can impact your mood, and even other, more serious, mental health issues.
How do these all work together for brain health?
The honest answer to how these things all work together is that we really don't know just yet. More and more studies are being done to learn more.
But one thing is becoming clear. A healthy gut goes hand-in-hand with a healthy brain!
So, how do you feed your brain?
Of course, a variety of minimally-processed, nutrient-dense foods is required, because no nutrients work alone.
But two things that you many consider eating more of are fiber and omega-3 fats. Fiber (in fruits, veggies, nuts & seeds) help to feed your awesome gut microbes. And omega-3 fats (in fatty fish, walnuts, algae, and seeds like flax, chia, and hemp) are well-know inflammation-lowering brain boosters.
Recipe (Gut food fibre, Brain food omega-3): Blueberry Hemp Overnight Oats
1 cup blueberries (fresh or frozen)
1 cup oats (gluten-free)
1 cup almond milk
1 tablespoon chia seeds
2 tablespoons hemp seeds
½ teaspoon cinnamon
1 banana, sliced
¼ cup chopped walnuts
1.Blend blueberries in the food processor until smooth.
2.Mix blueberries, oats, almond milk, chia seeds, hemp seeds in a bowl with a lid. Let set in fridge overnight.
3.Split into two bowls and top with cinnamon, banana, and walnuts.
Serve & enjoy!
Tip: Your gut microbes love to eat the fiber in the blueberries, oats, seeds, and nuts. Meanwhile, your brain loves the omega-3 fats in the seeds and nuts.
Glycemic this and glycemic that. Does it matter?
You'll notice that they both begin with "glycemic." That's one tip that they have to do with sugars and carbs. Not only how much sugar is in foods, but more importantly, how it affects your blood sugar levels.
In general, diets that are high on the glycemic index (GI) and high in glycemic load (GL), tend to increase the risk of diabetes and heart disease.
FUN FACT: Starches like those in potatoes and grains are digested into sugar; this is because starch is just a bunch of sugars linked together. Digestive enzymes break those bonds so that the sugars become free. Then those sugars affect your body the same way that eating sugary foods do.
Glycemic Index (“how fast”)
The most common of the two terms is “glycemic index” (GI).
As the name suggests, it "indexes" (or compares) the effect that different foods have on your blood sugar level. Then each food is given a score from 0 (no effect on blood sugar) to 100 (big effect on blood sugar). Foods that cause a fast increase in blood sugar have a high GI. That is because the sugar in them is quickly processed by your digestive system and absorbed into your blood. They cause a “spike” in your blood sugar.
So, you can probably guess that pure glucose is given a GI rating of 100. On the other hand, chickpeas are right down there at a GI of 10.
Regarding GI: low is anything under 55; moderate is 56-69, and 70+ is considered a high GI food.
Remember, this is a measure of how fast a carbohydrate containing food is digested and raised your blood sugar. It's not a measure of the sugar content of the food.
How the carbohydrates in food affect your blood sugar level depend on other components of the food. Things like fiber and protein can slow the release of sugar into the bloodstream, and this can make even a high-sugar food, low on the GI scale.
So, lower GI foods are better at keeping your blood sugar levels stable because they don't increase your blood sugar level as fast.
FUN FACT: Can you guess which food has a GI of higher than 100? (Think of something super-starchy) White potatoes! They have a GI of 111.
Glycemic Load (“how much”)
The glycemic load is different.
Glycemic load (GL) doesn’t take into account how quickly your blood sugar “spikes”, but it looks at how high that spike is. Basically, how much the food increases your blood sugar.
GL depends on two things. First, how much sugar is actually in the food. Second, how much of the food is typically eaten.
Low GL would be 0-10, moderate GL would be 10-20, and high GL would 20+.
Example of GL and GI
So, let’s compare average (120 g) servings of bananas and oranges:
Excerpt from: Harvard Health Publications, Glycemic index and glycemic load for 100+ foods
As you can see, the banana and orange have almost the same glycemic index.; this means they both raise your blood sugar in about the same amount of time.
But, the average banana raises the blood sugar twice as high (11) as the orange does (5). So, it contains more overall sugar than the same amount (120 g) of orange.
Of course, this is all relative. A GL of 11 is not high at all. Please keep eating whole fruits. :)
What does this all mean for your health?
Certain people should be aware of the effects that foods have on their blood sugar. People who have diabetes or pre-diabetes conditions like insulin resistance
need to be aware of the glycemic index and glycemic load of foods they are eating regularly.
The GI and GL are just two factors to consider when it comes to blood sugar. Some high GI foods are pretty good for you but if you want to reduce the impact on your blood sugar, have them with a high-fiber or high-protein food.
If you have blood sugar imbalances or diabetes, you should probably be aware of the GI and GL of your food.
If you are at risk of diabetes or heart disease, you might try swapping out some higher GI/GL foods and replacing with lower GI/GL foods.
Oh, and try this low GI recipe I have for you.
Recipe (low GI): Mediterranean Salad
1 cucumber, chopped
½ cup chickpeas, drained and rinsed
½ cup black olives
¼ red onion, diced
½ cup cherry tomatoes, halved
¼ cup extra virgin olive oil
1 tbsp apple cider vinegar
2 tbsp lemon juice
1 tsp garlic
1 tsp basil
½ tsp oregano
1 dash sea salt
1 dash black pepper
Place first five ingredients together in a bowl.
Add remaining ingredients to a jar (to make the dressing) with a tight-fitting lid and shake vigorously.
Add dressing to salad and gently toss.
Serve & enjoy!
Tip: Add chopped avocado for even more fiber and healthy fat.