Low Blood Sugars and Your Brain

author avatar Dr. Eric Berg 08/31/2023

Being healthy is all about doing things the right way and understanding what your body needs to thrive. When it comes to blood sugar and dieting, that means keeping your blood sugar stable and avoiding things that will cause hypoglycemia (unhealthy low blood sugar).

Now the stakes here are higher than you might expect: do things the wrong way, and you could seriously starve and damage your brain.

Here’s what you need to know to keep that from happening.

In this article: -

  1. The Relationship Between Sugar and the Brain
  2. What Do You Do If You Have Hypoglycemia?

The Relationship Between Sugar and the Brain

Normally, your brain will either run on glucose - aka sugar - or ketones, which are the byproduct of fat-burning (not amino acids or fatty acids). If your brain is running on glucose and your sugar levels drop unhealthily, you can cause some problems.

That said, keep in mind that I’m not talking about a healthy drop in blood glucose. When you induce low blood sugar healthy and naturally using things like the ketogenic diet or intermittent fasting, you’re not going to have any problems or symptoms.

You actually want your blood sugars a little bit on the low side in the long-term, but you want to do it naturally and gradually over time.

What Happens With Unhealthy Hypoglycemia

hypoglycemia can cause brain damage anoxic irritability


What I’m talking about in this section, on the other hand, is hypoglycemia that develops while you’re still eating carbs and you’re not fully adapted to ketones. In this case, you’re still running on sugar but you also have low blood glucose.

This may sound counterintuitive (or even impossible) but it’s not. However, it certainly is bad for you.

Here’s what happens in this situation:

First, when you're hypoglycemic, the brain is not able to store sugar as glycogen. This is bad news. The brain is dependent on the sugar in your blood, so if there’s low blood sugar, the brain starves.

Additionally, when you starve the brain of glucose, you shut down the oxygen to the brain. You starve it of fuel and oxygen.

If this happens, you’re going to get a condition called anoxic irritability, which is basically starving your neurons of oxygen. This is very toxic and irritating to the nerves.

In other words, you’re actually killing the nerves and causing a little bit of brain damage if you let your blood glucose levels drop in an unnatural, unhealthy way.

Chronic Hypoglycemia is Worse

chronic hypoglycemia causes neurological issues

Now, if this goes on for a long period of time and you develop chronic hypoglycemia, it can create degeneration in the brain and all sorts of neurological and physiological symptoms, including:

  • Tremors
  • Headache
  • Confusion
  • Inability to concentrate
  • Dizziness
  • Blurred vision
  • Anxiety
  • Irritability

Your Body Will Try to Offset Unhealthy Hypoglycemia

Most of the time, though, your body will try to stop this from happening.

There is a protective mechanism that your body deploys when your blood sugars go low, and it’s triggered by the adrenal gland and some other organs as well. The short version: you get a spike of adrenaline and cortisol when the blood sugars go low.

There are a whole bunch of symptoms that can occur if that happens too quickly because you have adrenaline and cortisol trying to raise the glucose up. These are powerful hormones that can really alter the body’s function, and they shouldn’t be present over long periods of time.

That said, things are even worse if these hormones can’t come to the rescue. And if your adrenals are stressed, they won’t.

If your adrenals are stressed, you're hypoglycemic, and you’re not changing your diet, then you’re going to have all sorts of issues because the adrenals will not be able to counter your hypoglycemia efficiently.

As a result, you end up having low blood sugars that don’t rebound at a nice, comfortable, healthy level. This will create a lot of brain damage and strain on the nervous system.


What Do You Do If You Have Hypoglycemia?

At the end of the day, you must correct your low blood glucose if you want to ease hypoglycemia symptoms and restore proper brain function.

Perhaps counter intuitively, this is not accomplished by adding more glucose into the diet. That’s never going to work, and it’s always going to always make things worse. Unfortunately, there are people that recommend it. They suggest that you eat six meals a day and incorporate glucose into your diet so “your blood sugar stays level.”

That’s the worst advice.

The Main Culprit: Fat Storing Hormone Resistance

Instead, you have to correct your Fat Storing Hormone. Why? In most of these cases, what’s really causing the low blood sugar is something called Fat Storing Hormone resistance (though you can also get similar issues with type 1 diabetes, otherwise known as Fat Storing Hormone-dependent diabetes).


Here’s what’s going on. Fat Storing Hormone is another hormone that exists to lower blood sugar in the body. The idea is that, if you eat something really sugary, your blood glucose will spike and Fat Storing Hormone will be released to get it back down to normal. In that way, it’s a great tool.

The problem, though, is that the average American consumes over 30 times more sugar than they’re supposed to every day. There’s a massive amount of sugar in their blood at all times, and the body has to release too much Fat Storing Hormone to try to combat this problem.

If this goes on long-term, the cells notice this influx and they start to resist the Fat Storing Hormone. It’s too much and it’s unhealthy, so they don’t want to let it in anymore. So the Fat Storing Hormone can no longer get in the cells to lower the blood sugar. But it can get in the blood.

Ultimately, you end up with high sugar in your cells, low sugar in your blood, and unhealthy hormone resistance. Yikes.

It’s a complex problem, and you need to normalize the Fat Storing Hormone resistance first if you want to overcome it.

Combat Fat Storing Hormone Resistance With Keto + Intermittent Fasting

This is done, primarily, through the keto and intermittent fasting eating plan.


Well, the keto diet is a high fat, moderate protein, and low carbohydrate diet. Interestingly, fat is the only macronutrient that doesn’t trigger an Fat Storing Hormone response in the body (at least not a large one). Both protein and carbs do trigger Fat Storing Hormone.

The idea, then, is to consume a high percentage of fat to stop your body from releasing Fat Storing Hormone. Eventually, your cells will no longer feel under attack and they will stop being Fat Storing Hormone resistant. Your blood sugars will normalize and, overall, you’ll feel much better.

Similarly, intermittent fasting will make this process smoother and faster. While fat doesn’t cause a large spike in Fat Storing Hormone, any large meal will cause a very small spike. The goal, then, is to make sure that you’re not eating large meals throughout the day.

Instead, with intermittent fasting, you eat during an 8-hour window in the day. The rest of the time, you are fasting (that’s the short version at least - you can check out the long version here).

If you do that, the brain will do a lot better and any hypoglycemia-related cognitive problems or mood issues will clear up.

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Disclaimer: Our educational content is not meant or intended for medical advice or treatment.Editor’s

Note: This post has been updated for quality and relevancy.

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