Reactive Hypoglycemia
Reactive hypoglycemia is a condition in which the body reacts to a
perceived catastrophic drop in blood sugar. I say perceived because
during an episode, the blood sugar readings may be in the normal range,
but still "feel" like low blood sugar to the person having the reaction.
In my experience,
hypoglycemia happens to most people when first beginning a low carb, ketogenic diet.
It may be especially strong in people who have already developed
insulin resistance or pre-diabetes from a chronic excess of carbohydrate
intake. There are different types of low blood sugar causes.
Transient hypoglycemia normally happens when most people who
have been eating a high carb diet drastically reduce carbohydrate intake
for the first time. This type happens during the first several weeks
of carb reduction because the body has not had time to create the
enzymes or metabolic state to burn internal fat stores for fuel.
Basically there is a gap in the amount of carbohydrate available for
fuel, and the process of accessing fat stores for fuel. The lack of
fuel sources results in transient low blood sugar.
Reactive hypoglycemia
is more of an acute reaction to a very high carb meal. For instance,
when a person eats 2 or 3 glazed donuts, there is a huge spike in blood
sugar and compensating insulin secretion after such a meal. The large
insulin spike drives blood sugar very low several hours after the meal.
How Reactive Hypoglycemia Happens
Insulin, a hormone, is secreted from the pancreas in response to
eating food, especially foods high in carbohydrates. Its main job is to
move the sugar your body makes from the food you eat into your cells so
that this excess sugar can be broken down for energy or stored. Insulin
is a very powerful hormone, and it acts very quickly. The amount of
insulin your body secretes is closely tied to how much blood sugar is
being created from food.
Eating a high carbohydrate diet over a
long period of time will cause a chronic elevation of your blood sugar,
which results in a chronic elevation of your insulin levels. High
levels of insulin are associated with inflammation and obesity, mainly
because when insulin levels are elevated, fat storage is increased, and
burning stored fat for fuel is inhibited. It’s a sort of vicious circle
- the more carbohydrate eaten, the higher the insulin, the less stored
fat can be accessed to fuel the body, so more carbohydrate has to be
eaten to provide fuel instead.
One of the benefits of eating a
ketogenic diet is its ability to lower your average blood sugar and
insulin levels, and allow the body to burn stored fat. However, when
first starting the diet, your body might still be in high carbohydrate,
high insulin mode.
As you lower your carbohydrate intake, you
begin a process of retraining your body to burn stored fat instead of
carbohydrates for fuel. Normally, it takes from 1-3 weeks for the body
to adjust the new lower level of carbohydrate intake, and build the
enzymes needed to burn stored fat.
Meanwhile, during this
adjustment phase, your pancreas is still secreting enough insulin for
the older, higher level of carbohydrate consumption. And remember,
because insulin levels are high, the body is dependent on carbohydrate
for fuel, since stored fat can't be accessed.
Your body hums
along with less carb intake for a couple of days because it can tap into
the stored carb (glycogen) in your liver and muscles. But eventually,
the glycogen stores get low, more insulin is secreted than actually
needed, and
a couple of hours later, you have a severe episode of hypoglycemia.
Your
body perceives that your blood glucose is too low, and starts evasive
tactics to get that sugar from somewhere. It pumps out adrenalin
(epinephrine) to tell the liver to break down stored glycogen or amino
acids into glucose FAST and dump it in the blood stream, while the
nervous systems pumps out acetylcholine, a neurotransmitter which acts
on the sweat glands, causing profuse sweating.
The adrenalin and acetylcholine cause symptoms that are associated with reactive hypoglycemia:
- heart palpitations or fibrillation
- dizziness
- light-headedness
- sweating
- headaches
- nervousness
- irritability
- shaking and tremors
- flushing
- craving for sweets
- intense hunger
- nausea, vomiting
- panic attack
- numbness/coldness in the extremities
- fatigue and shakiness for hours afterwards
Generally,
drinking or eating something that is high in carbohydrate, like orange
juice or candy, relieves the majority of the symptoms after about 15
minutes. There may be some residual fatigue and shakiness for a time
afterwards. (I've have episodes of reactive hypoglycemia so bad I was
still shaky 6 hours later.)
In my experience,
eating 1-2 glucose tablets are an easier and faster way to relieve the symptoms.
When beginning a ketogenic diet, I highly recommend buying some glucose
tablets or glucose drinks like the ones below and carrying them around
with you. They are available at most discount stores in the diabetic
supplies section.
In addition, my friend Luke, who loves rock climbing, swears by a product called SuperStarch by UCAN.
He says it has helped him get past some hypoglycemic episodes when he
started a keto diet. He says the product is marketed as a gluten free
sports drink, and supplies sodium and potassium as well as carbohydrate
to help with low blood sugar. He writes "It has really saved my bacon
more than once and allows me to stay on my ketogenic diet with
confidence."
I have never used Superstarch, but Dr. Peter Attia at the Eating Academy blog
uses this product and he's pretty savvy about ketogenic diets and exercise.
How to Avoid Reactive Hypoglycemia
In the short term, when first starting a low carb diet, eating more frequently may help.
Long
term, the best way to avoid reactive hypoglycemia is to permanently
reduce the amount of carbohydrate that you eat on a daily basis.
This
will eventually lower your daily blood sugar and circulating insulin.
Once insulin returns to normal levels, your body can then access its fat
stores, and quickly switch over to burning fat for fuel when you go
without a meal or two.
During the first phases of eating a lower
carb, ketogenic diet, it’s a good idea to make sure you eat every 3-4
hours. Until you can retrain your body to burn fat, don’t try to go for
more than 4 hours without food.
Paradoxically, some people who
experience chronic hypoglycemic reactions report that waiting 5-6 hours
before the next meal actually helps reduce the reactions.
Be aware that mainstream physicians
aren’t generally knowledgeable about this condition because it is
rooted in nutritional causes. Doctors aren’t taught about the power of
nutrition, and so he or she may minimize your concerns about it.
But
if you having these reactions, it indicates you are becoming insulin
resistant, and that can mean you are on a path to diabetes, even if your
fasting blood sugar is normal.
You may have to reduce your
carbohydrate consumption slowly over a longer period of time to minimize
these reactions, but eventually, by continuing to consume a diet lower
in
high carb foods, you should be able to avoid reactive hypoglycemia completely.
