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Does low carb reduce blood pressure?

S

Skinny43

Well-Known Member
Messages
75
Hi,

I felt dizzy today when walking down stairs. This was 2 hours after meal so I did glucose test it was 5.6 and blood pressure was 91/61. And I have felt dizzy for a couple of times in the last few weeks already.

I historically suffer from low blood pressure. But usually it’s fine after meal. Usually 90/60 before meal and 110/70 after meal. Could it be the low carb diet causing my lower than normal blood pressure?

I have been on low carb high fat for about a month now. Weight has dropped by 2-3kg despite eating regularly. I am 164cm tall and am ~50kg now. I do eat a lot of meat and fat but still lost weight. Could the low blood pressure mean I need to eat more and maintain my weight? BG usually is 6-7 after meal. So maybe I just ate too litter carb today (5.6 2 hours after meal)

Thanks and please help!
Ruiyan
 
Low carbing and or weight loss caused my BP to drop causing dizzy spells, to the point where I had to halve my BP meds! As you’re not on BP meds that’s not an option for you. I would suggest you check you are drinking enough but also get a check up with your GP. Getting giddy on the stairs doesn’t sound great.
 

Thank you! Good point to keep water intake. I don’t think I drank anything for the morning then tea with lunch. I don’t normally do tea (normally just water). Maybe I should try drinking more water and see. I’m very notorious for not drinking enough water!
 
Most people of the thin side of the scales need to eat more proteins and fats to maintain or gain weight. Eating more carbs is likely to raise the bgl as well as the kgs. I think increase the water (and electrolytes importantly), protein and fats and if that doesn’t work quickly then I’d get checked over by the dr.
 
From personal experience, yes. Mine is now on the low side of normal having been 158/102 on diagnosis: no meds just a ketogenic diet. There’s also this recently published research paper by Dr David Unwin and colleagues:

https://www.mdpi.com/1660-4601/16/15/2680
 
Yes, I would suggest there is some correlation too. I recently lost a little bit more weight, on top of the 4st I've lost over the past few years, and for no apparent reason, my blood pressure was really low, I felt faint and dizzy and struggled with lack of energy etc.

After a few weeks, went to GP who reduced, by half, my Blood Pressure meds that I'd been on for a few years. However, I decided not to take the lower dose until my blood pressure came up again (having stopped BP meds just before seeing GP). In fact, my blood pressure has stayed at a good, acceptable level so currently not on any meds for blood pressure
 
Thanks all for your kind replies and advices. I have increased my water intake and have not felt dizzy in the last few days. I haven’t measured blood pressure yet so can’t be sure but I feel better. So hopefully it’s resolved now.
 
It certainly did in my case. I have staged down my BP medication to half I was on a year ago. It has enabled me to do that.

Carefully though to avoid it dropping too low, which it hasn’t yet.
 
My understanding of it is that insulin influences a receptor on the surface of certain kidney cells (think of the receptor as a lock in a door that insulin helps to unlock) and that the more insulin in the blood in this case the that lock is opened and the less salt that can escape into the urine. More salt retained in the blood, the higher the Blood pressure.
With low carb diet there is less insulin secreted or needs injecting so the more unlocked the receptor is and the more salt passes into the urine leading to lower BP. See youtube videos of Dr Steven Phinney, particularly Nutritional ketosis and Keto-Adaption.
 

Thank you for a detailed explanation of the mechanism. I’ll check out the video later. Sounds like It might help if I take slightly more salt.
 
This time last year I was in difficulty. I had a long-standing heavy cold, my diabetes symptoms were becoming more entrenched. My blood pressure was increasing (home monitor). I visited one of my GP’s and asked to be referred to a dietician but was refused as I wasn’t overweight enough. He then increased my blood pressure medicine.

The key thing that worked for me bringing my blood pressure down, was a lower carb higher fat diet.
 

Hi skinny,
There are very complex feedback systems to maintain blood pressure in the human body.
Perhaps, if you have changed you're diet to lowcarb it may stabilise eventually if you don't have a defective feedback system.

The hormone that maintains blood pressure is generated in the adrenal glands and is called aldosterone.

Too much insulin, according to some authorities hacks the renin/angiotensin/aldosterone system and puts up blood pressure. If someone reduces insulin it may reduce blood pressure.
Normally low sodium would cause that system to increase blood pressure in humans low in sodium. It's a survival mechanism from the days when food was not reliable in early man to maintain BP by increasing aldosterone.

I have Conn's syndrome and my right adrenal has a tumour that produces 20x the normal aldosterone, so I have difficulty getting my BP down and getting rid of sodium.
My feedback system doesn't work.

Some adrenals produce too little adosterone and this results in low blood pressure.
There are many other reasons for BP anomalies and they need expert attention by perhaps an endocrinologist. GPs cannot sanction all the tests.
I hope you do not have a serious problem.
Best wishes
Derek
 
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Thank you so much Derek for explaining the science of it and your story. I should definitely keep an eye on my BP over a period and see the GP if needed. When I checked yesterday it was SLIGHTLY higher than what it was so perhaps it’s on its way to mend .

Thanks again and all the best to you.

Ruiyan
 
And, @Skinny43 I might need to lower my carb intake to eliminate all dependence on blood pressure medicines, even though my blood sugar levels are at normal levels.
 
My blood pressure dropped a lot on low carb.

From morning average 144/92 down to morning average 105/65. The drop happened rapidly too - over a couple months.

I have to make sure I get enough electrolytes.
My best method is drinking kettle and fire bone broth, but that is expensive! Sometimes I just add salt to my warm water. Not too tasty, but keeps the dizziness away.
 

Very good point! I shall remember to drink more water and get enough electrolytes. I’m thinking bone broth too!
 
I think that stock cubes dissolved in hot water (perhaps with a knob of salted butter) might make a useful electrolyte drink.
I enjoy it, anyway.
 
My blood pressure was normal, 120/80 usually when I started LCMF. It has decreased after 5 years to about 110/68. However, I have also lost 30 pounds and increased my exercise considerably during that time. Also during that time I have had a couple of alarming spells of dizziness during which I have been close to fainting. It has taken hours to feel normal again. Overall though my health is hugely improved!!
 
I really enjoy Miso soup. Is it a good candidate for electrolytes by any chance? If it is it’s a win-win!
 
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