When the liver begins to convert the alcohol to acetaldehyde and acetate, some of these chemical compounds will cross the blood-brain barrier.

For our safety, the blood-brain barrier doesn’t let many things cross through it, but because these compounds are both water and fat soluble, they are able to make their way through.

When these compounds get into the brain, they are indiscriminate as to where they go. What’s shown in the data is that they tend to go to areas of the brain that are responsible for certain kinds of thinking and behavior. For example, studies show that it leads to a suppression - a lessening - in the activity of the neurons in our prefrontal cortex. Which is the area of our brain responsible for thinking and planning. And if you’ve ever been drunk before, then this makes sense to you.

This lesser activity in the prefrontal cortex leads to more impulsive behavior and leads to lesser decision making ability. And of course, most of you know that this is the case when you’re in the middle of drinking alcohol, but it also impacts the circuits of your brain moving forward as well.

Studies show that alcohol consumption will lead to lower activity in the prefrontal cortex during times when you’re not drinking as well. Studies show that alcohol consumption not only leads to impulsive behavior while you're drinking but also more impulsive behavior when you're not drinking - that is compared to baseline. 

One bright side of this story, is there are studies that show this impact on the prefrontal cortex is reversible for some people and to some extents. You may be able to abstain from alcohol for 2-6 months and see a rebound in this prefrontal cortex activity.

Lastly, in the literature discussed by Dr. Andrew Huberman, he recites studies that show people who drink on average 1-2 drinks a day or 7-14 drinks per week, over time, will have less gray matter in their brain and more white matter. 

To keep it short and sweet, gray matter indicates a healthy brain with good levels of cognitive ability and more white matter indicates a less healthy brain with worse cognitive ability. 

Alcohol is converted into acetaldehyde and acetate which can both cross the blood-brain barrier. These compounds can then impact our prefrontal cortex leading to a lesser ability to perform tasks of thinking and planning both in the moment and in the future. 

Alcohol can lead to less amounts of healthy gray matter in the brain and more amounts of unhealthy white matter.

I thought this next part was fascinating. 

In our bodies there is something called the Hypothalamic Pituitary Adrenal Axis or for short - the HPA axis.

Let’s break that down. 

Hypothalamic - the hypothalamus is in our brain and it’s one of the most important parts of our brain as it regulates so many processes. 

Pituitary - the pituitary gland is also in our brain and is responsible for producing different hormones in our body.

Adrenal - the adrenal glands sit on top of our kidneys and play a critical role in hormone production. 

So, we the hypothalamus and pituitary are in our brain and the adrenals sit just above our kidneys. The hypothalamus provides specific signals to the pituitary glands which then release hormones into the bloodstream that talk to your adrenal glands. And your adrenal glands release the hormones of epinephrine and cortisol - hormones associated with stress.

This HPA Axis is the link between our brain and our endocrine system. It’s the link between experiencing stress in the world and our physiological response to stress that follows. 

So, how is this impacted by alcohol? Well, when we consume alcohol, studies show that our HPA axis is negatively impacted. And not just when we drink; chronic consumption of alcohol shows negative impacts on the HPA Axis in the future even when we're not in the process of consuming alcohol. 

Studies show that regular alcohol consumption (7-14 drinks per week) can lead to higher levels of stress and anxiety when we're not drinking. The HPA axis is more likely to produce cortisol - our stress hormone - even when we’re not drinking if we are a chronic drinker.

But again, this HPA axis is modifiable. It can change over time. If you decrease your drinking habits, you are less likely to experience as much stress during times when you’re not drinking. 

Our hypothalamic pituitary adrenal axis or HPA axis for short is our link between perceived stress and our physiological response to stress. It’s the axis responsible for what stress hormones are released inside of our body given our experience with the outside world.

Studies show that if we are chronic alcohol drinkers, which Dr. Huberman defines as drinking on average 1-2 drinks per night or 7-14 per week, then our HPA axis is more likely to produce more stress hormones like epinephrine and cortisol even during times when we’re not drinking. Which leads to greater levels of stress and anxiety.

When you hear the words gut microbiome, you should think about a colony of millions upon millions of bacteria inside of your gut. 

Alcohol impacts our gut microbiome in 4 ways:

- Dysbiosis

- Leaky Gut

- Overconsumption

- Nutrient Absorption

Let's start with dysbiosis.

Some of these bacteria are good bacteria and some are bad.

At any given point in time, we want the population of good bacteria to be much higher than the population of bad bacteria.

If we have a higher population of bad bacteria, then we are said to have dysbiosis. If we have dysbiosis, then we are more likely to experience inflammation, digestive issues, cognitive decline, and more.

Alcohol is in cleaning products because of its ability to kill bacteria. And when we drink alcohol, it also kills bacteria inside of our body. And it is indiscriminate as to which bacteria it kills. And that results in alcohol killing a lot of the good bacteria inside of our gut. And overtime this can lead to this state of dysbiosis.

The other way alcohol impacts our gut is our gut lining. The lining of our gut is made of up millions and millions of cells that act as a barrier or a security system. And it decides what gets absorbed into the bloodstream and what doesn't.

If we have a healthy gut lining, then we are able to properly regulate what gets absorbed into the bloodstream and what does not. We are able to keep out harmful bacteria or particles from going into the bloodstream and wreaking havoc.

But, if we have what’s called leaky gut, or intestinal permeability, that means we have holes in our gut lining, that makes our security system weaker. It leads to harmful particles to leak out of the gut and into the bloodstream leading to a cascade of negative effects. And alcohol can poke these kinds of holes into our gut lining. 

Those are two ways that alcohol directly impacts our gut health, but unfortunately it doesn’t stop there. Our brain and our gut are in constant communication by way of the vagus nerve. And when we drink, our gut communicates to our brain that we want more of it and can cause us to want to drink more. Leading to overconsumption. 

Lastly, consuming alcohol decreases our ability to absorb nutrients from the food that we eat. 

When we eat, our body will either digest and absorb the nutrients in our food or it will excrete it in our urine or stool. Digestive enzymes and the presence of stomach acid are responsible for the absorption of these nutrients, but when we consume alcohol we are lowering our digestive enzymes and lowering the amount of stomach acid that we have. Therefore, instead of absorbing some of the healthy nutrients from our food, we will be excreting it.

Consuming alcohol will kill the good bacteria and our gut and will help populate the bad bacteria leading to dysbiosis. Alcohol will cause a breakdown in our gut lining, leading to leaky gut. 

Our gut, when consuming alcohol, will communicate to our brain that we want more of it. And if we drink more of it, then obviously all of the other negative effects are heightened. 

When we consume alcohol, our body becomes less and less effective at absorbing healthy nutrients from the foods we eat.

When we say alcohol tolerance, that refers to the reduced effects of alcohol with repeated exposure.

If we say our tolerance is high, we mean that we have to drink more to feel the effects of alcohol.

And if our tolerance is low, we will start feeling tipsy or drunk more quickly.

Our tolerance level is really impacted by the neurotransmitters released in our brain and the levels of alcohol dehydrogenase that we have in our system.

Let’s start with the latter - alcohol dehydrogenase. If you remember back to the beginning of the blog, alcohol dehydrogenase is what converts alcohol into acetaldehyde. When we have greater levels of alcohol dehydrogenase we are able to metabolize and clear alcohol more quickly, therefore not experiencing the tipsy or drunk feeling as soon.

And when we drink more alcohol, our body will have greater levels of alcohol dehydrogenase therefore increasing our so-called tolerance.

Another way our tolerance is impacted is through the neurotransmitters of dopamine and serotonin. These neurotransmitters are largely responsible for motivation and mood. When we drink alcohol, we experience a spike in the production of both dopamine and serotonin followed by a long slow decrease. 

If we have a lower tolerance, we experience a larger spike in dopamine and serotonin.

If we have a higher tolerance, we experience a smaller spike. This leads people with a high tolerance to drink more to seek out the elevation in mood that they desire.

This is another one of those systems that is modifiable over time - as a lot of you know. Your tolerance can go up or down in a relatively short period of time. 

Just try being someone who drinks 7-14 drinks a week and then go without a alcohol for a month and see what happens...

Our alcohol tolerance will impact how much we consume or don’t consume. If we have more alcohol dehydrogenase in our bodies, we’ll have a higher tolerance. And if we have a high tolerance, our mood spike won't come as quickly therefore causing us to drink more to seek out that elevation in mood. 

Okay, take a deep breath.

I know it sounds like I just went on and on and on about the negative health effects from alcohol. 

And well ya, I did. 

And no...red wine is not healthy for you either. Resveratrol, the component of red wine that some people claim to be healthy, is a compound that yes, is healthy for our bodies. But the amount of resveratrol in red wine is very low compared to the amount we would need to experience the benefits resveratrol provides.

We would have to drink tons and tons of red wine to get to the beneficial effects of resveratrol, and by that time, you’d probably be passed out face down in a ditch somewhere. 

Given all I’ve said, does that mean that I personally am going to stop drinking alcohol altogether? No.

At least I don’t plan on stopping now.

But does it make me reconsider how much I drink? Yes.

I’m someone who wants to live a super healthy life, but I also want to have a high-quality life. And sometimes that means that I’m okay with doing unhealthy things every now and then. 

And alcohol is one of those unhealthy things that I’m okay with doing every now and then because of the enjoyment I get from it.

And I know a lot of you feel the same way. I know a lot of you reading are similar to me - you enjoy drinking alcohol from time to time, but when you drink too much you sometimes wake up the next morning thinking, why did I do that? Was that even worth it?

And while you enjoy drinking, you don’t want it to cause excess weight gain and you don’t want it to cause a rapid decline in your brain health and metabolic health. 

Given the science that I discussed today, I’ll provide you with tools and tips that I’ve either applied in the past, will apply in the future, and things I’ve learned to lessen the negative impacts of alcohol on our health.

I hope to provide you with a realistic approach that will allow you to enjoy your alcohol when you want to, and have the discipline to abstain from it when you’d like.

I know for some people, not drinking alcohol altogether is the right way to go. And if that’s you, more power to you. That’s just not me at this current time.

I hope the science provided today empowers you to make better decisions when it comes to drinking.

Stay tuned for next week’s blog on how to manage your alcohol consumption to keep your health in check.

If reducing alcohol consumption is something you know you need to do in order to hit your health and fitness goals, I’m here to help. I’ve coached over 600 people through the 10-Week Transformation and at least ⅓ of these people have set goals to reduce alcohol consumption and I can help you, too.

The next 10-WT starts April 22nd, but it’s not open for registration until March 7th. In the meantime, sign up for the 1-Week FREE Trial at www.nickcarrier.com/freetrial.

To getting closer to your Best You,