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Test fast 72 hours

R

Ruthbcn

Member
Messages
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Hi @Lamont D !

my endocrine has proposed to me to test the fast of 72 hours in a hospital. I have reactive hypoglycaemia for 3 years, and the test is very scary because I do not think I can take it. My glucose After 3 hour in ogtt is 3.How could I resist 72 hours? I'm also very scared of the results. Can you give me some recommendation? thank you.

sorry for my bad english
 

Hi @Ruthbcn,
I can only tell you of my own experience of having the 72 hour fasting test.
You don't have a glucose tolerance test, a fasting test is different, it is to determine if you go hypo without food, or not, if you do have RH, you should not go hypo!
I wasn't in hospital for the full four days, my fast started the evening previous, so the first twelve hours were at home, then due to organisational problems, I was kept busy, having bloods done and getting a bed. I found that after the first day, as long as I kept myself occupied, walking, reading, watching television, it wasn't so bad, I knew that hospital food was awful, so I didn't mind missing it!
I did find the constant overnight blood testing a bit annoying, but other than that, the actual fasting was easy. You may be using a continuous glucose monitor. I was apprehensive and anxious but to no avail, I learned a lot from fasting, and I now find fasting helps me cope daily.
Unfortunately, the test is a necessary part of diagnosis, to find or eliminate what condition you do actually have.
I would recommend it, especially if the care is good. Getting to the cause of what is happening to you is really important and of course, the right treatment.
Let us know how you get on.

Best wishes
 
Thanks a lot @Lamont D !

my fear is how I will be able to endure 72 hours, since I need to eat something every three hours to avoid hypoglycemia ...
 
Ok, I have RH!
The true reactive hypoglycaemia diagnosis is Hypoglycaemia caused by food converted to glucose rapidly, then an overshoot of insulin forces your blood sugar levels down into hypo levels.
If you wake up in normal levels, and you don't eat, then a RH er will not react. It is food that causes the trigger for the hypers then the hypos! Carbs, hypos, no carbs or no food at all, no hypos!
The reason why you are recommended to eat every three hours is to stop the hypos, but if you don't have the carbs for breakfast, then the rest of the day, you will not get the reactive part. No rises in blood sugar, no trigger, no hypos!
Do you have normal blood sugar levels before breakfast?
Have you noticed that you get ill after a carb laden or starchy foods?
If you have a salad with protein, you don't get the symptoms. It is food that causes the symptoms!

So if you are fasting, you should not need to eat every three hours because you won't have to stop you going hypo!

That is why a long fasting test is necessary, to see wether you go hypo or not!

I was recommended on diagnosis to eat every three hours, I couldn't do it! Then found I didn't need to if I reduced my carbs, I found having stable blood sugar levels, all the time, got rid of symptoms, made me healthy, and the hypos stopped. You only have to eat every three hours if you eat carbs earlier.

I haven't had a hypo in about five years, because I don't eat the foods that causes the symptoms and the hyper/ hypo rollercoaster ride of fluctuating blood sugar levels.

Reactive Hypoglycaemia means you are carb intolerant. It is this intolerance that causes the horrible symptoms, that causes the blood sugar levels go up and down.
An intolerance means you should avoid these foods, just as if you are allergic to them.

Try not having carbs as much as possible, you will see the difference.

Best wishes.
 
Thanks a lot @Lamont D !
You have helped me a lot and I will follow all your good advice.
Your explanation has encouraged me a lot. It is exactly what happens to me.
Gracias!,
 
Ruthbcn said:
Thanks a lot @Lamont D !
You have helped me a lot and I will follow all your good advice.
Your explanation has encouraged me a lot. It is exactly what happens to me.
Gracias!,
Click to expand...

De nada!
Muchas gracias!
 

Hi Lamont D,
I became confused..

You said, “Reactive Hypoglycaemia means you are carb intolerant. It is this intolerance that causes the horrible symptoms, that causes the blood sugar levels go up and down.”

That is so true !!
‍

But you said, “So if you are fasting, you should not need to eat every three hours because you won't have to stop you going hypo!”


This means if we do not eat carb, we do not have hypo, right ?

But my case, if I did not have breakfast, I got hypo ..
now I have breakfast everyday, so I do not have hypo....


I am confused...

Also I had night sweats
( my pajama became wet
a lot even in a cold winter time ) sometimes, is this the symptom of hypo ?

I am having very low carb diet..., but I am craving for sugar and carb... very difficult to keep continue.. what do I need to do ??

The other day I had a small cup noodles, then my blood glucose became 13.5 and after that I had a hypo..
I ate chocolate
straight away.

I eat cheese
and cream
to compensate my sugar and carb craving, then I have got weight... ( once I reduced to 51kg, but now I have 53kg )

It is hard to lose weight, because my adequate weight is 54kg and hard to lose weight.. I was aiming 48kg, but I failed.. low carb diet is not easy for long run..

How do you manage the sugar craving ?

I am in trouble at the moment..

Your experience and knowledge is extremely helpful!

Thank you very much.
‍
 

Hi again, hope you are coping better now you have reduced your carbs, it will make a difference, you just have to stick with it, have the episodes of Hypoglycaemia reduced?

An intolerance is a food, that causes your blood sugar levels to go up and down, it also triggers the brain to compensate for low glucose and low insulin as the imbalance of hormones effect blood sugar levels.
The symptoms are the effect of the roller coaster ride of blood sugars fluctuating up and down.
This is how I stay away from going hypo, no carbs, intermittent fasting, it does work for me. You are still in that transitional phase from carbs to no carbs. So you body is craving carbs. I would still ask why you are having hypos after breakfast if you are still eating something that you are intolerant to. I have lactose intolerance, so anything dairy, though if full fat dairy it is low carb, but most dairy products still effect me. You may not know it, that is why food diary is so important. If you would have told me that I'm potato intolerant, I would have laughed at you!
Again, noodles are bad for me, so it would not surprise me that you had a hypo.
In my experience, it took a good couple of months to start losing weight, again, you have just started low carb, so be patient and it will change. Then after trying very low carb and fasting, it fell off me, I went from nearly 18 stone down to twelve stone, I've been around that weight for a few years now.
I don't have sugar craving! Don't feel hungry! I feel better most of the time not eating!
It's called Keto adapted, when you try to get into ketosis, you can get Keto flu, which is still getting symptoms as you describe, your body has not adapted to being in ketosis, then without realising you find symptoms alleviating, you get good energy, your brain fog goes, you feel better and you should not go hypo! It is really hard and getting use to, you need strong will power. You need to get your family and friends to support you. Planning, organising, keeping temptation away, and the most important, getting your head around, that this condition can be controlled, it will not get worse, if you avoid the hypos, and if you get control, you will lose weight, your symptoms will go, you will get healthy!
This lifestyle is so important to your future health!
It is sustainable, it is doable, and it should not be a burden to your life's goals.
You can get your life back!

Best wishes, let us know how you are getting on!
 

Hi Lamont D,

Thank you very much for your reply !! Very valuable for me !!!!

So I should be patient...

I am lactose intolerant as well. Also gluten intolerant, but I can eat sometimes..

I used to live on rice... so low carb diet is very hard for me... I do not feel full in my stomach, so I feel hungry ..

Usually my diet is like this:

Breakfast : 1 boiled egg and half bowl
of cooked buckwheat.
This does not raise my blood glucose.

Snack : another half bowl
of buckwheat as a snack.

Dinner : big bowl of salad and meat.


Snack : cheese
with crackers.

I used to eat rice
or gluten free pasta
with dinner.. but now I do not eat any..

But I have a carb craving.
This is a problem.

My body is struggling, but I should keep doing this low carb diet.

I will let you know how it goes , I hope I will feel better.


You do not have hypo !
Amazing !
I still have ..


Thank you again for your valuable advice !! It makes me feel better , I am not the only one .. we can support each other.. great group !!
‍I sincerely appreciate !!

‍
‍
 

Can I ask a question about this?

I recently had a GTT (postpartum follow up after having gestational diabetes) and my results were:
Fasting - 4.4 mmol
1h - 12.1 mmol
2h - 6.5 mmol

On my own metre, which I used before, during and after that same GTT I got:

Fasting 5.0 mmol (on waking a couple of hours earlier)
1h - 13.8
2h - 8.5 and 7.5 a minute on either side of the lab's blood draw.
3h - 3.4 (at home) with some dizziness / mild shaky feeling

The doctor said I don't have diabetes but the note on the lab report said "may have glucose intolerance - test again in one year"
The doctor also didn't know about the 3.4 I got 3 hours after the GTT.

At the moment I am breastfeeding a 3 month old but usually in the morning if I skip breakfast my fastings of high 4s when eating low carb tend to rise into the 5s. Today I ended up in the 3s (3.4) after being up and hour and a half, from 4.4 on rising. I expected to see 5s. Could be the breastfeeding taking me down.

Anyway, my question!

With the 72 hour fast, what does it mean if you go into low 3s VS if you stay higher? Is one a diagnosis of diabetes VS reactive hypoglycaemia?
And is low carb the solution for both anyway?
 
Cocosilk said:
Anyway, my question!

With the 72 hour fast, what does it mean if you go into low 3s VS if you stay higher? Is one a diagnosis of diabetes VS reactive hypoglycaemia?
And is low carb the solution for both anyway?
Click to expand...

Here is a link you may find interesting.
http://www.endobible.com/investigation/supervised-72-hour-fast/
As described here, the 72 hour fast is not to diagnose RH, since it does not start with a glucose tolerance test.
Diabetes is not diagnosed by low blood glucose.
So the 72 hour fast is to diagnose non-reactive hypoglycaemia, which may have a number of causes.

The 5 hour glucose tolerance test is useful in diagnosing insulinomas
https://www.ncbi.nlm.nih.gov/pubmed/2096054
and in diagnosing RH
https://www.medscape.com/answers/12...the-diagnosis-of-hypoglycemia-low-blood-sugar
however there seems to be quite a variation in the level at which different health care teams diagnose these things.
https://www.hindawi.com/journals/crim/2013/273957/
There has been considerable debate regarding the level of glucose that defines hypoglycaemia, and this has ranged between 2.2 mmol/L and 4.0 mmol/L [3].

My own view is that the test results have very limited usefulness where RH is concerned (and incredibly valuable usefulness in diagnosing other conditions).
They may give handily comparable test results for health care professionals to base clinical RH diagnosis on, but in real life... totally different story.

In my case, a 75g glucose test will produce a very different result from a 75g mixed meal test, or a test containing gluten, or a test containing rice rather than glucose.

Since I live in a world where I do not ever drink 75g glucose on an empty stomach and then sit around waiting for a hypo, I think the OGTT is a waste of my time, and will not willingly ever have another test.

On the other hand, I can replicate RH hypos from 15g of gluten containing carbs, or prevent one by eating those 15g carbs without gluten and with a protein/fat meal. For me, real life trumps the laboratory every time, and I have no intention of chasing a diagnosis when a simple diet adjustment (in my case, gluten free low carb) can keep me well and not in need of that diagnosis.
 
Last edited:

Thanks for explaining all that!

I think it's sensible not to bother with the tests. I wouldn't like to do another GTT ever again. Maybe a HbA1c sometime just to have peace of mind.

As far as chasing a diagnosis goes, I was just curious because I haven't read much about RH and had no idea how those fasting tests work or how they even diagnose you. I wouldn't be doing a 72h fast in any case as I'm breastfeeding still and I doubt my dips into the 3s is non-reactive. Mine have been in the presence of breastfeeding or a carb hit, so I guess they lean mor eto the reactive side, which must mean I would never hypo from starvation (is that right??).
I was wondering if low carb is always the solution to these metabolic disorders, and it sounds like it is so you are right, there's no need to test really - as you say, you just need to eat accordingly.

It's really interesting how you discovered the way gluten containing carbs do that to you (and probably to many others).
I'm still on and off with certain foods that I am finding hard to let go of - sourdough bread for one, and I was just using the same rye flour to make crepes. Something else I love to have. If I eat a few crepes and see 5.9 mmol at 90 mins, I tell myself it's okay to have them every now and then. I'm not fully committed to eliminating anything for good yet, well, except for pretty much all processed foods. One day, when I'm done breastfeeding, I'll probably try some more elimination diets and do keto more strictly again.
 
Cocosilk said:
I was wondering if low carb is always the solution to these metabolic disorders.
Click to expand...

There are metabolic disorders (many) where low carb won’t be beneficial.
There is a huge range of different disorders.
An insulinoma is one example. Thankfully, they are rare and can be identified by the both tests linked above.
 
As @Brunneria has said there are many conditions that are called metabolic syndrome and that is what you may have.
What I get, when I read from your glucose tolerance test is the 13mmols from the hour recording.
This could be 'gastric dumping'! This also happens in quite a lot of metabolic conditions because the initial insulin response is weak because of insulin resistance mainly. There are of course different reasons why you can get that reading, for example, low insulin response levels as in types of T2 and other conditions.
There is no true test for the condition of RH! It is a series of tests to eliminate other conditions such as insulinoma. Any metabolic imbalance especially from hormone response will of course give different results. The symptoms and results from tests could also give symptoms of hypoglycaemia but not the condition of RH.
Confusing, isn't it!
Glucose intolerance is another way of saying carbs intolerant, wheat intolerant, lactose intolerant and so on, if the result is your blood glucose levels go too high, or you get that rebound effect, and symptoms from the sudden rise, sudden drops in blood glucose levels, you will have and get the symptoms of a typical metabolic/diabetic patients, which includes the types of Hypoglycaemic conditions.
I have never as a RH patient, had a hypo fasting or not eating, RH is a condition that is a reaction to food.

I believe that the way you describe your fasting levels, I would not be overly concerned about having one or two mmols difference within normal levels range. Having a high three or a low six is in normal range, and I would advise to continue the tests as diagnosis is important to your future health and how you treat your condition whatever it is. If you have a condition such as RH, you would not want to be treated for a hypo as a T2 or T1!
Especially if it something more serious!
Which would be exposed during the 72 hour fasting test! If for example, insulinoma, pancreatitis or pancreatic cancer, the hypo is not food orientated.
From this fasting test, more tests are done to find the cause, which would include scans and invasive biopsies.
Because of not having a hypo in the 72 hours fasting test, RH is usually diagnosed, but more glucose tolerance tests are done and more blood work.

Hope that helps.
 
Hi. I was the same. They keep it going for 72 hours unless you sugars drop to 2.2 then they take bloods and stop the test. Mine went the whole 72 hours and dropped to 2.5 feeling like rubbish and freezing cold but recovered quickly after food
 
Discovery22 said:
Hi. I was the same. They keep it going for 72 hours unless you sugars drop to 2.2 then they take bloods and stop the test. Mine went the whole 72 hours and dropped to 2.5 feeling like rubbish and freezing cold but recovered quickly after food
Click to expand...

When during the tests did you go hypo?

Because if you did go hypo, it is not RH!
 
Lamont D said:
When during the tests did you go hypo?

Because if you did go hypo, it is not RH!
Click to expand...

I spent most of the second day around the 3.5 mark then dropped to the 2’s. They said it’s not a true hypo until it goes down to 2.2 which I found odd as I’ve always read that under 4.0 is classed as hypo. I usually start getting symptoms around 4 or just under
 
My specialist endocrinologist, who is also a professor of endocrinology at a big university, has quoted to me a few times, that a hypo is below 3.5mmols.
Of course, we get symptoms of a hypo at various blood sugar levels. I don't get full blown symptoms until under 3 (ish) mmols but I get the vision blurring and headache under 4(ish). But that was years ago now! I had a really bad experience in hospital during my first eOGTT, when I didn't know what was happening to me after the test was stopped, nor did the doctor, sister or nurse that was there to look after me, it took a phone call to my specialist to tell them to stop pushing carbs on me.
I really can't believe that someone who suffers from hypo symptoms and are under normal levels are not in a hypo episode! (Unbelievable!)
I went home after twelve hours in a state, going hyper then hypo because of the rebound effect of trying to stop the hypos!
That didn't happen again when I went hypo, I learnt a lot from my successive eOGTTs and fasting test, and I was in total control when I had my mixed meal test.
 

I may sound dumb but what is a mixed meal test...I’ve never had one of those or been offered one
 
Discovery22 said:
I may sound dumb but what is a mixed meal test...I’ve never had one of those or been offered one
Click to expand...
It is a test in hospital, where different types of food, protein, fat, carbs are used, it is similar to a smoothie, I think it's called a 'boost'.
It is used to test insulin response, and is a test also for type 1 diabetes.
 
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