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HR surges after meals - blood sugar or MCAS?

Bergkamp

Senior Member
Messages
145
Hi all,

It's now been over 3 months since my major crash in June and my nervous system is still completely out of whack. Sometimes it seems to calm down but then the smallest trigger just makes it running again.

On days where my ANS is out of control, my HR is low in the morning before breakfast, in the evening before sleep and between meals. However, shortly after eating meals my HR goes up a lot and then stays high for about 2-3 hours. It often goes accompanied with an adrenaline rush and a rushed, nervous feeling. This doesn't happen every time, when my ANS is very calm my HR stays low. It happens 80% of the time though (I also have rushes during the night). It never happened before this crash. My question is: could this be due to MCAS or blood sugar rushes? I am diagnosed with MCAS but I eat a very low histamine diet and I take a high dose of sodium cromoglycate before every meal. My GP says that I still can get mast cell reactions though despite these measures. Could this be the case? My GP wants me to take an antihistamine to see what happens but I've had bad experiences with mast cell meds in the sense that when I take them I feel no benefit but then when I stop I crash so I become dependent to them.

What do you think?
 

Mimicry

Senior Member
Messages
179
I sometimes have similar problems after eating. It became worse after I had Covid in February, and is getting better little by little and I rarely get that racing heart/lightheaded feeling after eating anymore.

I thought it was due to unstable blood sugar and cutting out sugar from my diet for a couple months actually helped. I also started taking H1 and H2 antihistamines and think that probably helped a little bit for a while. Now I'm also thinking it could partly be a vagus nerve thing, since I've had weird anxiety/nausea/stomach issues for the last four months. Vagus nerve literally controls blood pressure and heart rate as well as digestion so I'm pretty sure disordered or damaged vagus nerve could cause the sort of crashes you're describing. Especially when you're having a bad ANS day it could just be that your vagus nerve is acting up.

Do you have benzodiazepines and/or beta blockers? They might help with the heart rate thing.
 

Bergkamp

Senior Member
Messages
145
I sometimes have similar problems after eating. It became worse after I had Covid in February, and is getting better little by little and I rarely get that racing heart/lightheaded feeling after eating anymore.

I thought it was due to unstable blood sugar and cutting out sugar from my diet for a couple months actually helped. I also started taking H1 and H2 antihistamines and think that probably helped a little bit for a while. Now I'm also thinking it could partly be a vagus nerve thing, since I've had weird anxiety/nausea/stomach issues for the last four months. Vagus nerve literally controls blood pressure and heart rate as well as digestion so I'm pretty sure disordered or damaged vagus nerve could cause the sort of crashes you're describing. Especially when you're having a bad ANS day it could just be that your vagus nerve is acting up.

Do you have benzodiazepines and/or beta blockers? They might help with the heart rate thing.

Thanks for your reply. I cut out sugar too from my diet. There is definitely something wrong with my vagus nerve, I have severe dysautonomia. But I didn'thave this type of reactions to food before my crash in June. I do take a beta blocker, 80mg propranolol. I ake Ativan for sleep and rarely Xanax to combat an adrenaline rush but can't take that too often.
 

xebex

Senior Member
Messages
840
it might not be reaction to the individual foods but a reaction to eating - all your blood is going to the gut which will make dysautomomia worse, if your blood volume has lowered some how this could be a cause, i would say dysautonomis is the likely culprit.

you could rule out blood sugar issues by gettign BG monitor, its hard to say otherwise.

could also be MCAS as that is implicated in dysautonomia but without other mcas type symptoms id be more inclined to say dysautonomia.
 
Messages
79
I have 100% same symptom, if I eat too much, my HR will rise up to 90-100. And my heart beats stronger, so I can feel pounding. And yes, I feel nervous and wired when this happens. It calms down only after a few hours.
Avoiding too much food calms down my ANS, and I feel so much better between meals.
At first I thought it was NAC that calmed down my HR, but no, it was avoiding too much food is what helped me the most
I don't know why this happens, and what can help it in the long term.
 

xebex

Senior Member
Messages
840
I have 100% same symptom, if I eat too much, my HR will rise up to 90-100. And my heart beats stronger, so I can feel pounding. And yes, I feel nervous and wired when this happens. It calms down only after a few hours.
Avoiding too much food calms down my ANS, and I feel so much better between meals.
At first I thought it was NAC that calmed down my HR, but no, it was avoiding too much food is what helped me the most
I don't know why this happens, and what can help it in the long term.
I think it’s due to low blood volume. It’s normal for the blood to be directed to the gut after eating but if you have low blood volume the nervous systems going to start freaking out that there’s not enough blood flow in the rest of your body.
 

Atlas

"And the last enemy to be destroyed is death."
Messages
117
Location
New Zealand
I get a similar thing with HR if I'm in a crash and eat large meals. I also have severe POTS.

I saw Dr. Vallings before she retired and she said to eat little and often because it's common for blood to pool in the stomach if you eat large meals. That could be causing the fast HR like xebex noted.

Consistent pacing and eating the same amount but less at a time has helped me with this. For example for my lunch I just eat half of it, then wait about an hour or so to eat the rest. When I'm not in a crash I can sometimes eat the whole meal without a problem.
 

Bergkamp

Senior Member
Messages
145
I think it’s due to low blood volume. It’s normal for the blood to be directed to the gut after eating but if you have low blood volume the nervous systems going to start freaking out that there’s not enough blood flow in the rest of your body.
Thanks a lot. That does seem like the most logical explanation indeed.
Consistent pacing and eating the same amount but less at a time has helped me with this. For example for my lunch I just eat half of it, then wait about an hour or so to eat the rest. When I'm not in a crash I can sometimes eat the whole meal without a problem.
That makes sense - unfortunately difficult for me due to gastroparesis and SIBO, which means that I can only eat 3 meals per day and need to have sufficient time in between..
 
Messages
79
I think it’s due to low blood volume. It’s normal for the blood to be directed to the gut after eating but if you have low blood volume the nervous systems going to start freaking out that there’s not enough blood flow in the rest of your body.
I don't understand why it supposed to be low? I don't have hypotension. Moreover, my BP slightly increases on standing (not always, but there is a pattern).
My blood pools in my arms (but not in legs), maybe that's the explanation of low blood volume in brain? Raising my hands doesn't decrease HR unfortunately.
I think food digestion is decent task for ANS even for healthy people, so the brain is trying to help digest the food by raising sympathetic activity. Unfortunately, my ANS overreacting and there is too much fight or flight.

P.S. I want to add, that ANS overreacting basically to anything. Any stressful situation, or some heavy physical activity, and I can feel my heart pounding in my neck. And HR skyrockets instantly.
 
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xebex

Senior Member
Messages
840
I don't understand why it supposed to be low?

it’s just one theory and as you say you have blood pooling so that would be causing a type of low blood volume - hypoxia in the brain or other parts of the body.
Also I’m not sure if low blood volume necessarily causes low blood pressure - that’s why the HR goes up to keep blood pressure normal.

i also do not know why the blood volume gets low but if you do have low blood volume drinking oral rehydration solution could help.
 
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overtheedge

Senior Member
Messages
258
if i eat meals w sodium over 20%, several grams of saturated fat, high fat or high calorie my hr goes high fr several hours, it could be something like that in the food
 

Mimicry

Senior Member
Messages
179
i also do not know why the blood volume gets low but if you do have low blood volume drinking oral rehydration solution could help.

The blood volume gets low because our pituitaries, adrenal glands and hypothalamus (hypothalamuses? Hypothalami? I'm not fluent in Latin) are typically not producing enough hormones that keep the blood volume on a steady level - namely, aldosterone (salt hormone, keeps your kidneys from dumping sodium into the urine) and vasopressin (also known as ADH, antidiuretic hormone, which tells your kidneys to retain water in the body). Angiotensins are the hormones that stimulate aldosterone production and renin is the one that stimulates angiotensin production, and the whole system is out of whack in the bodies of pwME. In other words, we pee our blood away. I need 1-3 tsp of extra salt in salt water per day to keep hydrated, because if I drink plain water, it just goes straight through me and I feel like I have a hangover 24/7 (I can't drink alcohol anymore, but it's ok, I get the hangover even without drinking. Saves a lot of money!). It's very common for pwME to pee like a racehorse and be thirsty all the time.

https://www.healthrising.org/blog/2...onic-fatigue-syndrome-pots-renin-aldosterone/
 

xebex

Senior Member
Messages
840
@minicry ahhh! You know I’ve researched into it a lot and not once found a decent explanation! Guess I wasn’t reading the right stuff! Thank you!
 

Haley

Senior Member
Messages
1,178
Location
NSW Australia
Like others, my heart rate rises after eating a large meal. My resting heart rate also rises by 30-50 bpm for anywhere between 4 and 10 hours after eating anything that is moderate to high carb content. The length of the rise spend a on exactly what I've eaten and how much.
Needless to say I eat a low carb diet because trying to rest with a heart rate at that level is almost impossible.
 

hapl808

Senior Member
Messages
2,052
Yep, happens to me. My HR jump isn't huge (maybe up 10bpm-20bpm for awhile), but it's pretty common after meals and seems more related to how my overall symptoms are going rather than what I eat. Since my baseline is usually high (80-100), it's quite irritating and obviously not very restful. Not sure that it's MCAS for me as cromolyn, zyrtec, pepcid, quercetin, vit C, etc didn't seem to make a big impact on it.
 

gregh286

Senior Member
Messages
976
Location
Londonderry, Northern Ireland.
Hi
This happens me.also and coincendentally just took a new face.last 4 weeks.
I now get skipped beats and heart pauses.
You can really feel it because your heart is pounding hard at same.time.so a flutter is really noticeable. Sugar and fast carbs like rice and choc really do a number on it. Red wine as well if you drink over 2.or 3 glasses.

I also agree its low blood volune and blood divert to gut during glucose digestion makes it much worse and insulin is a massive dilator i can see the hand veins standing up.

I think the chamber in the heart doesnt get full up enough when i get this heart 'pause' so definerly not enough blood returning to heart in time for next beat

Then body panics and atart beating faster etc. Total ciculatory confusion.
Unnerving at start but once you had it a dozen times you can put it on the fck it list of just another symptom.
My normal baseline HR is 55. It can jump to 80.
 

gregh286

Senior Member
Messages
976
Location
Londonderry, Northern Ireland.
The blood volume gets low because our pituitaries, adrenal glands and hypothalamus (hypothalamuses? Hypothalami? I'm not fluent in Latin) are typically not producing enough hormones that keep the blood volume on a steady level - namely, aldosterone (salt hormone, keeps your kidneys from dumping sodium into the urine) and vasopressin (also known as ADH, antidiuretic hormone, which tells your kidneys to retain water in the body). Angiotensins are the hormones that stimulate aldosterone production and renin is the one that stimulates angiotensin production, and the whole system is out of whack in the bodies of pwME. In other words, we pee our blood away. I need 1-3 tsp of extra salt in salt water per day to keep hydrated, because if I drink plain water, it just goes straight through me and I feel like I have a hangover 24/7 (I can't drink alcohol anymore, but it's ok, I get the hangover even without drinking. Saves a lot of money!). It's very common for pwME to pee like a racehorse and be thirsty all the time.

https://www.healthrising.org/blog/2...onic-fatigue-syndrome-pots-renin-aldosterone/

Couldnt agree more
Pee like a racehorse and drink liie a fish.
Always parched.
We are peeing away our ""volumisers""... the minerals and fluids that bulk up our volumes.
 

gregh286

Senior Member
Messages
976
Location
Londonderry, Northern Ireland.
Hi all,

It's now been over 3 months since my major crash in June and my nervous system is still completely out of whack. Sometimes it seems to calm down but then the smallest trigger just makes it running again.

On days where my ANS is out of control, my HR is low in the morning before breakfast, in the evening before sleep and between meals. However, shortly after eating meals my HR goes up a lot and then stays high for about 2-3 hours. It often goes accompanied with an adrenaline rush and a rushed, nervous feeling. This doesn't happen every time, when my ANS is very calm my HR stays low. It happens 80% of the time though (I also have rushes during the night). It never happened before this crash. My question is: could this be due to MCAS or blood sugar rushes? I am diagnosed with MCAS but I eat a very low histamine diet and I take a high dose of sodium cromoglycate before every meal. My GP says that I still can get mast cell reactions though despite these measures. Could this be the case? My GP wants me to take an antihistamine to see what happens but I've had bad experiences with mast cell meds in the sense that when I take them I feel no benefit but then when I stop I crash so I become dependent to them.

What do you think?

Unlikely anti histamine will do any good.
I take 3 a day for angioedema.and still this issue is as.obbvious with or.without it.
This is a sugar...low volune...dehydration.....blood.pooling issue.
Low carb cures it.
Little and often cures it.
My threshold.seems.to be around 20g carb max in one sitting. Anymore asking for trouble.

Mineral wafers should help it also but many have so much added crap.
I did use simplynatural wafers a few years ago and they were brill but just got too expensive to maintain.
May order them again.
 
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sb4

Senior Member
Messages
1,654
Location
United Kingdom

This video goes into it a bit. It's focused on POTS but most people with ME/CFS have POTS like issues.

The gist is blood pooling / low blood volume resulting in diabetic like glucose issues. The solution on the video is low carb and small regular meals, a solution that I would have imagined most of us would have already gravitated too. Still it was interesting in the vid how lean pots patients responded like obese diabetics post prandially.
 

Husband of

Senior Member
Messages
313
Hi all,

It's now been over 3 months since my major crash in June and my nervous system is still completely out of whack. Sometimes it seems to calm down but then the smallest trigger just makes it running again.

On days where my ANS is out of control, my HR is low in the morning before breakfast, in the evening before sleep and between meals. However, shortly after eating meals my HR goes up a lot and then stays high for about 2-3 hours. It often goes accompanied with an adrenaline rush and a rushed, nervous feeling. This doesn't happen every time, when my ANS is very calm my HR stays low. It happens 80% of the time though (I also have rushes during the night). It never happened before this crash. My question is: could this be due to MCAS or blood sugar rushes? I am diagnosed with MCAS but I eat a very low histamine diet and I take a high dose of sodium cromoglycate before every meal. My GP says that I still can get mast cell reactions though despite these measures. Could this be the case? My GP wants me to take an antihistamine to see what happens but I've had bad experiences with mast cell meds in the sense that when I take them I feel no benefit but then when I stop I crash so I become dependent to them.

What do you think?
This sounds like my experience with COVID (including now, four weeks in, though ti a lesser extent to what it was in previous weeks). So I'd guess whatever the reason it's what happens when you are sick, and the reason you are noticing it now is that you are more sick than you used to be)