Everything You Need to Know About Hypoglycemia: Causes, Symptoms, and Treatment
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Updated 6/15/2024
Understanding Hypoglycemia
Hypoglycemia is low blood sugar. The clinical definition is having blood sugar (or blood glucose… same thing) below 70mg/dL. A lot of the people experiencing hypoglycemia are taking insulin or other glucose-lowering medications. I’m not going to be talking as much about this, specifically. If you are taking insulin, your diabetes educator is the best person to discuss this with. Medication recommendations are beyond the scope of this article, but you may still find some useful information here.
This article is to help build your awareness of all the OTHER causes of hypoglycemia so we can learn to identify and avoid it. Because not only does it cause unwanted symptoms, it can lead us on a cycle of snacking, overeating and worsening metabolic health.
What Does Hypoglycemia Feel Like?
Not everyone notices the symptoms of hypoglycemia when they drop below 70mg/dl. They are more likely to occur the closer you get to 60mg/dl. The symptoms include:
Dizziness
Sweating
Shaking
Rapid heartbeat
Hunger
Confusion, irritability
These are the signs of clinical hypoglycemia which tend to occur when blood glucose levels get closer to 58mg/dl. They are severe and can knock you flat.
Mild hypoglycemia symptoms
A state of subclinical reactive hypoglycemia (SRH) has also been described in the literature which is when blood glucose isn’t low enough to trigger the severe symptoms listed above, but it does trigger strong hunger cues which lead to an increased frequency of eating. (1) In fact, when a new client tells me they get hangry and snack a lot, that’s a red flag that their blood sugar is out of whack and they are experiencing at least a mild form of hypoglycemia.
When I say “strong hunger cues”, keep in mind this is a survival mechanism for the body. What I mean by that is that by the time you’ve got yourself in this subclinical hypoglycemic state, your body is HARD WIRED for survival and is telling you (under no uncertain terms) to eat a damn sandwich (2). Willpower doesn’t work here.
Why do I feel hangry?
Of course, for most of us, it’s not a sandwich we eat when we feel hangry. You’ll get cravings for whatever your brain and body have learned will get your blood sugar up quickly. That means simple sugars (and another blood sugar rollercoaster). It’s usually a craving for juice, soda, an iced mocha, a bagel, chips, or a Snickers. Yes, SNICKERS has created an entire (successful) ad campaign on this biological principle. When you get “hangry”, you can kiss your willpower goodbye. You need to eat.
Let’s use some images to better describe this.
Image shows a healthy blood sugar curve staying in range (70-140mg/dl) and not dropping down below 70mg/dl after meals for data from cgm non diabetic graph.
Image shows a high glycemic meal “spiking” blood sugar over 140mg/dl and a subsequent drop below 70mg/dl into subclinical hypoglycemia.
This is because low blood sugar is so dangerous to your body and brain, that your body has redundant mechanisms to prevent it.
First, you’re hard-wired to consume something to get your blood sugar back up.
Second, your pancreas secretes glucagon, which tells your liver to release stored glucose into the bloodstream.
Third, your adrenal glands will secrete adrenaline (your fight or flight hormone) which ALSO tells your liver to release stored glucose to help you survive.
See how that hangry campaign was so brilliant and effective?
I can usually tell this is an issue with a client from talking to them and looking at their food record. But it’s unmistakable when my clients are using a continuous glucose monitor (CGM) as the data shows it in black and white. You can refer back up to the second graph showing “Subclinical hypoglycemia”.
Notice that subclinical hypoglycemia is happening after a high-glycemic meal. “High glycemic” means the food caused a glucose “spike”. A glucose spike is when blood sugar shoots up too high. For some, that’s over 180mg/dl, for others, they need to keep it under 140mg/dl. Our body really hates those spikes and prefers a gently rolling hill that’s easier to recover from. Eating a meal or drink that causes glucose/sugar to enter the bloodstream rapidly causes blood glucose levels to skyrocket. Then, depending on your body’s programming, your insulin response might have a tendency to overshoot the mark and bring it down too low. It’s understandable, really. Human bodies still haven’t caught up to modern food. In many ways, we’re out of our league with modern food products. This leads to hypoglycemia.
After your blood sugar plummets, you get the hangry sensation (or worse) which cues more high-glycemic eating or drinking and the cycle starts all over again.
If this cycle sounds and feels like an addiction to you, you’re not far off. The good news is there are pretty simple ways of avoiding the triggers which will make it way easier for you to stop the food addiction cycle.
How to Recover from Hypoglycemia
Remember, this article is NOT specifically for people with type 1 diabetes or others with severe hypoglycemia caused by taking too much insulin. We are focused more on subclinical hypoglycemia. But the strategy is much the same.
To recover, you’ll need to listen to your body. It needs glucose and it needs it now.
Use the 15-15 rule
The 15-15 rule helps us recover from low blood sugar but keeps us from overdoing it. You start by first eating some quick carbs… but just a little bit. Don’t go overboard with the sugar or you’ll be playing catch-up all day long. Here, we take a page from the diabetes playbook and follow their 15-15 rule. Consume 15 grams of carbohydrates to raise blood glucose and check again after 15 minutes. When it’s back to normal, eat a more balanced snack with protein and fat to even things out. If you don’t have a glucometer or a CGM, then you’ll need to go by your symptoms. If you feel symptoms improve in that 15 minutes, then it’s time to switch to a balanced snack.
Consume 15 grams of carbohydrates to raise blood glucose and check again after 15 minutes.
15 grams of rapidly-absorbing carbohydrates can be from:
4 ounces (1/2 cup) of fruit juice or sugary soda (not diet)
8 ounces (1 cup) of fat-free milk (the fat slows down the blood sugar and you don’t want that right now)
1 Tablespoon of honey, sugar, or corn syrup
Jellybeans, gumdrops, hard candy (refer to food label for amount)
Half a banana
15 grapes
2 Tbls. raisins
A small apple or orange
Glucose tablet
Remember, if you overdo it on these, you can cause a rebound effect. So start with a small serving, wait 15 minutes, then repeat until you feel better and follow that with some protein and complex carbohydrates, and fat. Like a balanced meal or snack.
People who take insulin follow the same advice. If this is you, then you probably carry glucose tablets for these emergencies.
Why does Hypoglycemia happen?
That’s the important question to ask. Because once you know this, you can avoid getting into this situation. There are a few ways I see hypoglycemia happening in my patients. They include:
Wrong dose of insulin (or other diabetes medication)
A procedure (like gastric bypass) done on your stomach changed your physiology
Incorrect fueling prior to exercise
A high-glycemic meal
Wrong dose of medication 💊 🧁
This is an obvious one that really deserves its own post. But something to keep in mind is that when you are embarking on a health journey to improve your blood sugar, you need to keep a close eye on your medications. When you are getting better control of your blood sugar using diet, exercise and better sleep, your need for blood sugar medication is going to go DOWN. When we use a CGM, we can see in real-time the need for medication adjustments so they can be dosed more accurately. Most of the time, it helps people taper off while minimizing unwanted symptoms of hyper- or hypoglycemia.
For example, a recent client used insulin to manage his type 2 diabetes then started taking Ozempic. We had him use a continuous glucose monitor so that as he made diet and exercise changes, he could gradually reduce his insulin dose every week or 2 to avoid hypoglycemia.
Surgery-induced hypoglycemia 🏥
I will often get patients referred to me by endocrinologists for hypoglycemia. They already have a CGM but don’t know how to stop their hypoglycemia symptoms or why it’s happening. The most common situation is a person who has had bariatric surgery in the past. Sometimes, months or years down the road, the person will start experiencing hypoglycemia. The research on this is unclear, but it appears that a small percentage of people experience this. They seem to have a rush of glucose into the bloodstream along with higher-than-normal insulin and gut peptides. This leads to severe hyperglycemia. These people effectively have reactive hypoglycemia and need to be much more careful with their blood sugar.
I spoke to Piera Carubia RD, CDN, IFNCP about this. She works with patients after their gastric bypass procedures in Rochester, NY. She finds that many of her patients start reverting back to old dietary habits that include more refined carbohydrates (like Wheat Thins). They also tend to eat less protein because it’s harder to digest with a smaller stomach. The combination of a low-protein diet that includes more refined carbohydrates is a recipe for disaster. After helping them develop an emergency plan for hypoglycemia, she helps them find the root cause of their hypoglycemia which often includes stress management, mindfulness (to help them catch the early signs of hypoglycemia) and a more balanced eating plan.
I’ve seen a very similar phenomenon occur in other people who have had surgical procedures involving the stomach including gastro-esophageal surgery for Barrett’s Esophagus and fundoplication. When I first looked at their CGM data, it looked just like the data from the bariatric patient. When I asked if they’d had any surgical procedures done on their stomach, their answer was a surprised, “Yes.”
Prior to being prescribed a CGM by their doctor, one patient assumed it was a symptom of a heart irregularity they had and ignored it. They mistook dangerously low blood sugar for a side effect of their heart issues and didn’t seek help.
It’s unclear to me the exact mechanism for this, but the solution is always the same: Tighter blood sugar control.
Incorrect fueling before a workout 🚴
The food you eat before your workout is important. Some people prefer to fast before exercising, but many eat 1-3 hours beforehand. The timing and macronutrient makeup can affect your blood sugar levels. Get it wrong and anything from a brisk walk to heavy squats can land you on your back with blurry vision and the shakes.
This is because while insulin is typically required to get glucose into most of our cells, exercise will induce insulin-independent glucose uptake into skeletal muscle. Those muscles get hungry for glucose when you work them and they will absorb a lot of glucose during your workout without any help from insulin. We use this to our advantage when we’re trying to manage our blood sugar. But it can backfire if you do it wrong.
For example, if you eat within an hour of your workout, you’ll want mostly carbohydrates with a little protein. If you add too much fat, it will keep your glucose levels elevated and lead to hypoglycemia during your workout. In her book Next Level, exercise physiologist Stacy Simms recommends simple strategies like a banana with some peanut butter, granola, or whole grain toast with nut butter. I’ll sometimes have a very small bowl of oatmeal with a few walnuts. I used to experience severe hypoglycemia during my workouts! I often drank a protein smoothie before the gym and would often find myself on my back after my first heavy squat set or after 10 minutes of going hard on a stair machine. Once I was using a continuous glucose monitor (CGM), I could see that my smoothie was raising my blood sugar and keeping it up too long. Before it came down, my workout added that extra insulin-independent glucose uptake stimulus and it dropped my blood sugar like a rock. It was like I’d injected myself with a few units of insulin!
After talking with one of the trainers at the gym, they warned me about adding too much fat to my pre-workout meal. That’s when I realized that while adding some healthy fat at other times made good sense, adding it to a pre-workout meal did NOT. I wanted my blood sugar to come back down to baseline prior to starting my workout and the fat plus carbs got it up and kept it up longer.
After this, I was able to use my CGM to better tailor that pre-gym meal and time it better to make sure I was back in the fasted state before working out. My earlier smoothie was too high in fat and kept my blood sugar up too long. If I was eating that close to a workout, I had to drop the fat content.
High-glycemic meals 🧁
Many of us can get by with eating high glycemic meals and ultra-processed food without noticing the way our body is dealing with it. But for those of us who have more sensitive metabolisms, these meals are like kryptonite.
For the folks who have had a gastric bypass, it can drop them down into serious clinical hypoglycemia. For some of my patients with dysautonomia (like POTS), it can trigger POTS symptoms. For others, the effects are more subtle but real. We call it subclinical reactive hypoglycemia and it’s at the root of weight gain, poor sleep and anxiety for many of my clients.
Dysautonomia, POTS and EDS
Hypoglycemia is also a common occurrance in people with dysautonomia. Dysautonomia is any disorder of the autonomic nervous system (the part of your nervous system that regulates everything in the background like your digestion, blood pressure, blood sugar, temperature, etc.)
POTS is short for postural orthostatic tachychardia syndrome and is the most common form of dysautonomia. POTS is commonly seen in people with Ehler’s-Danlos Syndrome (EDS) and presents in a variety of ways including feeling dizzy when standing, feeling a really rapid heartrate, easy bruising, swelling, migraines, etc. I put many of my EDS patients on a CGM to help them manage their blood sugar better because it helps them avoid hypoglycemia and THAT helps them manage their other POTS symptoms.
In fact, through my work with blood sugar, I often help identify young people who have undiagnosed EDS/POTS because we see their unexplained reactive hypoglycemia and discover they also have hypermobility and POTS symptoms.
If this sounds like you, I encourage you to click through some of the links here to learn more.
Subclinical reactive hypoglycemia
Avoiding subclinical reactive hypoglycemia is a strategy many of my clients use to better manage their weight and improve sleep and energy levels.
Subclinical reactive hypoglycemia (SRH) is when your blood sugar drops rapidly and might even go below 70mg/dl. But it doesn’t go low enough to cause the more severe autonomic symptoms listed above. Instead, the body just quietly craves another high-glycemic food or drink to get your blood sugar back up… NOW.
In fact, the classic advice of eating small, frequent meals throughout the day has made it worse and led many to just develop diabetes, frankly. It’s not that the advice is outright wrong, it’s just not thorough enough.
Most people follow the “small, frequent meals” advice by snacking their way through the day on meals that are high in simple carbs and low in protein and healthy fats. The result is chronically elevated insulin levels, excess belly fat, low energy, high triglycerides, and excess weight they can’t lose.
The way you SHOULD follow the advice can vary. But my advice is to start by eating 3-4 well-balanced meals throughout the day and making sure you have 20-30 grams of protein at each meal. At least, that’s for starters.
Using a CGM to prevent hypoglycemia
When I look at the CGM data from my patients who have hypoglycemia, it always (always) happens after eating a high-glycemic meal. So the #1 strategy is to keep blood sugar stable. This means we look at how your body handles food and eat in a way that keeps blood sugar under 140mg/dl after meals and the best way to do this is to use a CGM and follow the data.
The same strategies do NOT work for everyone. For this reason, most health professionals might tell you to do ALL the things to make sure you reach your goal. When you follow it, you’ll do great for a few weeks! But you won’t know which strategies were the most effective for you and get overwhelmed by all the lifestyle changes.
Using a CGM, we can try out strategies and only do the ones that work. We find the minimum effective dose of change necessary to keep blood sugar in check. Why is this important? Because a change is only worth it if you can stick to it. And small changes are easier to stick to than big ones.
When we use CGM to do this, we can immediately see what doesn’t work (and avoid that). Try different strategies that DO work (do them more often). Then these small improvements compound (like interest) to equal big metabolic improvements and better blood sugar control.
Here are some of my easy-to-implement strategies to help keep your blood sugar in check:
Follow the order of eating; the order of eating means:
Start your meal with protein and/or non-starchy veg
Choose carbohydrates that are lower glycemic and higher in fiber, and eat them AFTER your protein and fiber
Avoid naked carbs:
You may have heard the advice to avoid “naked carbs”. This is similar to the order of eating. Eating refined carbohydrates by themselves causes the glucose to enter your bloodstream too quickly and you can get the rebound hypoglycemia.
Don’t drink your carbs.
You may as well be mainlining sugar by drinking carbohydrates. This includes fruit juice, soda, your overly sweet coffee drink from your favorite coffee bar, and milk. In fact, milk or even half ‘n half in your coffee on an empty stomach will typically cause quite a glucose spike.
How Using a CGM Can Help Prevent Hypoglycemia and Bonking
We’ve already touched on some of this above, but let’s bring it all together here.
Accurate medication adjustments
Find the root cause of hypoglycemia
Learn to gauge pre-workout meals and timing
We use a CGM all the time to more accurately dose medications. Sometimes it helps us know when to ADD a medication like metformin or insulin. But more often, we’re using it to reduce the dose. As our clients are finding ways to better control their blood sugar, they have less of a need for their medications. Using a CGM eliminates the guesswork and (with the advice of their prescribing physician) they can customize their taper to avoid dangerous side effects like hypoglycemia.
Finding the root cause is probably obvious now. When our clients can see in real-time how every single time they get a hypo event, it’s preceded by a big blood sugar spike, they get it. It’s time to balance their blood sugar. They use the CGM to determine what meals work best for them and how they can hack their favorites in safely by, say, eating protein first.
For athletes or even for us mortals trying to stay fit, we can see clearly what meals work best before a workout and see when we’ve returned to a fasted state so our workout won’t cause us to bottom out. Endurance athletes will also be able to track in real-time during a long training session to create fueling strategies that optimize their performance and prevent “bonking”.
We run an awesome group program every other month that helps people learn how to Hack their blood sugar using a CGM. If you’d like to join the waiting list, it will give you more information about the program, provide you with a letter for your doctor to help you get a prescription for it, and line you up for exclusive early-bird discounts. We have 1:1 programs too if you are not a group person.
Conclusion
No matter the cause of your hypoglycemia, the solution is the same. Get better control of your blood sugar.
If you are experiencing more severe autonomic symptoms like dizziness, shaking and sweating, it’s pretty clear that you need to make some changes. It will be less obvious if you are experiencing subclinical reactive hypoglycemia unless you are more tuned into your body and recognize the patterns and the tell-tale “hangry” feelings that can come up.
Most of the strategies are pretty common sense and don’t require special technology to implement. Avoid eating those “naked carbs”, follow the order of eating, and don’t drink your carbohydrates. Flatten that blood sugar curve. But if you’re having trouble getting a handle on how to make this happen, the short-term use of a continuous glucose monitor makes this very straightforward. With supervision, we can get a lot of information about what works and what doesn’t work in just 2-4 weeks of use. The monitors we use tend to run about $80-140 for 4 weeks of use, so it’s a good return on investment. However, it really helps to have an expert look at the data with you to help you interpret and create strategies around what you see. If you are interested in learning more, you can download my free guide, LEARN ABOUT USING A CONTINUOUS GLUCOSE MONITOR, to learn more about using a CGM or read an earlier article on it.
Remember, if you are experiencing the more severe hypoglycemia symptoms regularly, you need to seek medical attention. Don’t put this off. The solution can be very simple and can not only eliminate the hypoglycemia episodes but will probably also help you feel better in many other ways.
References:
Kishimoto I and Ohashi A. Subclinical Reactive Hypoglycemia is Associated with Higher Eating and Snacking Frequencies in Obese or overweight Men without Diabetes. Endocrines 2022, 3(3), 530-537
Kishimoto I. Subclinical REactive Hypoglycemia with Low Glucose Effectiveness - Why We Cannot Stop Snacking Despite Gaining Weight. Metabolites. 2023 Jun; 13(6): 754