Blood pH
LabRat529
Posts: 1,323 Member
I hear over and over and over again about certain foods that can make blood more 'alkaline' or more 'acidic'. To the best of my knowledge, this is false. The pH of the blood is regulated by the respiratory system. The key component is carbon dioxide (CO2). The chemical equation for the bicarbonate buffering system in your blood is as follows:
(H+) + (HCO3-) <----> (H2CO3) <
> H2O + CO2
(sorry... had to improvise... that's not how you actually write a chemical equation, but that's as good as it gets on MFP)
You notice the CO2 in there? If you need to push the reaction to the right to get rid of excess acid (a.k.a. hydrogen atoms), you breath faster to get rid of CO2. You breath it off.
Conversely, if you need to push the reaction to the left to get rid of excess base, you breath slower.
This system is absolutely wonderful at keeping your body at a pH of 7.4
It CAN be over-powered... but usually it's by extreme metabolic stress (uncontrolled diabetes, for example).
If anyone can show me any scientific evidence (not hearsay, not testimonials, but real science where I can look at the graphs and experimental designs and see for myself if I agree with the scientists' interpretation of the data), I'd be thrilled. If I'm wrong, I'd really like to know.
(H+) + (HCO3-) <----> (H2CO3) <
> H2O + CO2
(sorry... had to improvise... that's not how you actually write a chemical equation, but that's as good as it gets on MFP)
You notice the CO2 in there? If you need to push the reaction to the right to get rid of excess acid (a.k.a. hydrogen atoms), you breath faster to get rid of CO2. You breath it off.
Conversely, if you need to push the reaction to the left to get rid of excess base, you breath slower.
This system is absolutely wonderful at keeping your body at a pH of 7.4
It CAN be over-powered... but usually it's by extreme metabolic stress (uncontrolled diabetes, for example).
If anyone can show me any scientific evidence (not hearsay, not testimonials, but real science where I can look at the graphs and experimental designs and see for myself if I agree with the scientists' interpretation of the data), I'd be thrilled. If I'm wrong, I'd really like to know.
0
Replies
-
I hear over and over and over again about certain foods that can make blood more 'alkaline' or more 'acidic'. To the best of my knowledge, this is false. The pH of the blood is regulated by the respiratory system. The key component is carbon dioxide (CO2). The chemical equation for the bicarbonate buffering system in your blood is as follows:
(H+) + (HCO3-) <----> (H2CO3) <
> H2O + CO2
(sorry... had to improvise... that's not how you actually write a chemical equation, but that's as good as it gets on MFP)
You notice the CO2 in there? If you need to push the reaction to the right to get rid of excess acid (a.k.a. hydrogen atoms), you breath faster to get rid of CO2. You breath it off.
Conversely, if you need to push the reaction to the left to get rid of excess base, you breath slower.
This system is absolutely wonderful at keeping your body at a pH of 7.4
It CAN be over-powered... but usually it's by extreme metabolic stress (uncontrolled diabetes, for example).
If anyone can show me any scientific evidence (not hearsay, not testimonials, but real science where I can look at the graphs and experimental designs and see for myself if I agree with the scientists' interpretation of the data), I'd be thrilled. If I'm wrong, I'd really like to know.
There was an issue about this a few months ago between a buff dude and another guy about chocolate milk being acidic.0 -
Rebekah, I am so glad you posted something about this. I've. Wondered about it for quite a while. My understanding was that the buffers keep our blood PH at a constant 7.4 regardless of what we ingest. So I have often wondered how the alkalai blood advocates could get away with preaching that. I will be interested to see if you get any valid response from them.0
-
Rebekah, I am so glad you posted something about this. I've. Wondered about it for quite a while. My understanding was that the buffers keep our blood PH at a constant 7.4 regardless of what we ingest. So I have often wondered how the alkalai blood advocates could get away with preaching that. I will be interested to see if you get any valid response from them.
I'm really hoping someone can explain the rational too... its possible I'm wrong, that I'm over-looking something. If that's the case, I'd like to know. Otherwise, I assume it's a myth.
I am curious how the myth (if it is a myth) got started. Even if its based on pseudoscience, pseudoscience usually starts with a misunderstanding of real science... so where'd it come from?0 -
It's all very confusing... I had a problem with being too alkaline and my doctor told me it was because my body wasn't absorbing the vitamin C that I was eating. I think there are a lot of factors that go into this.0
-
My understanding is that - to simplify - meat and animal products (protein) make the blood more acidic, while vegetables and grains make it more alkaline. If I'm wrong, I'm sure someone will correct me.
0 -
My understanding is that - to simplify - meat and animal products (protein) make the blood more acidic, while vegetables and grains make it more alkaline. If I'm wrong, I'm sure someone will correct me.
My question is... why does this happen, if it does actually happen? I'm a nerd and I think on a biochemical level... I just want to know how these components defeat your bodies built-in freakin'-awesome buffering system :P If they do... and I'm a skeptic... but I suppose anything is possible. I just found out that sugar is an analgesic, which floored me.0 -
Nah, your right. I'd like to see how a food is going to change the acidity of the stomach......not going to happen. All food that leaves our stomach is acidic and when in the intestines the pancreas neutralizes that acid, basically all food in our stomach is acidic and alkaline in the intestines......the body controls our pH, like you say.0
-
You are correct. It is absolute, complete and utter nonsense.
I frequently test people's blood pH, and trust me, what they have had for dinner, does not and could not, affect blood pH one iota. (unless you are dining out on a couple hundred aspirin or tricyclic antidepressants)
Your henderson-hasselbach equation is right on the money, and unless you have a severe respiratory problem (affecting that CO2), or a severe metabolic/renal problem (affecting that HCO3) your pH doesn't change outside a tightly controlled range of 7.35-7.45. Even if you do have a severe renal/metabolic/respiratory problem your body STILL doesn't allow your pH to change if it can help it, and will compensate like crazy to get it back to where it should be. If the change is too severe to compensate for, then that person is SICK.
Besides if anyone wants alkaline blood, just hyperventilate for a couple of minutes and see how THAT makes you feel.0 -
The pH actually ranges from 7.35 to 7.45 with an average of 7.4
Average blood bicarbonate is 25 ranging 22-28
Average CO2 dissolved in blood is 40.
Ever wonder why you get tired after eating? It's because for every bit of acid you make in your stomach, you pump equal bicarbonate into the blood. It creates an "alkaline" tide in the blood that results in feeling tired.
As far as people saying food changing pH, it can be seen in the urine quite easily but the blood is heavily buffered and it takes alot to get it out of its range.
Reason you can see it in urine is the kidneys filter and secrete acid. Meats and protein digestion results in alot of Uric and Phosphoric acid being excreted in the urine making it much more acidic than normal. Other foods can do the opposite specifically nitrate containing foods such as legumes which induce the kidneys to form ammonia and making it less acidic.0 -
I was under the impression that the body DOES balance the blood pH, but it uses essential nutrients to do so. So that consistently eating foods that make your body have to continually adjust your blood pH robs your body of nutrients it needs for other functions. Is this true?0
-
Anyone who consumes meat products will have a more "acidic" blood pH e so often it is slightly below 7.4 .. but NOT MUCH!! Like you said, the bicarbonate buffering system keeps us in homeostatic control and the fluctuations are so little and nothing to worry about.0
-
I was under the impression that the body DOES balance the blood pH, but it uses essential nutrients to do so. So that consistently eating foods that make your body have to continually adjust your blood pH robs your body of nutrients it needs for other functions. Is this true?
That's what I'm trying to get at. A lot of people think that your body uses nutrients to balance pH and that it uses nutrients needed for other functions, but that was not what I was taught in basic human physiology. So I'd like to know where the idea comes from and whether it's backed by any science.0 -
What exactly are you looking for. This can be approached from different angles. A study of what?!?!
I'll take a look at the article you linked. Unfortunately, I used my lunch break to lift weights and i need to get back to work... so... I might not have time to read it in depth until tonight.
However... to answer the question quoted above, I'd like a study that shows cause-and-effect. I'll even take a study in an animal model, but something that shows that blood pH changes either acutely or chronically following a acid or basic diet.
If I were to design such a study... I might feed fasted (and therefore hungry) rats a bunch of oranges and then measure their blood pH immediately after and at different time-points for the next 24 hours. Alternatively, I might round up a bunch of college kids, give them 20 bucks to fast, then eat some oranges, and let me take some blood. So something like that... something that reduces variables and shows cause and effect.0 -
Oh. That's urinary pH. That's a whole different ball of wax. As another poster mentioned, the kidneys concentrate things like uric acids, which are bi-products of protein metabolism, which can be due to normal protein turn over or due to eating an excess of proteins. That doesn't mean the blood or the interstitial fluid is outside the normal physiological pH range.
Still... that article definitely helps. Maybe the myth that food can regulate blood pH started with the observation that food can effect urinary pH? If so, the author of the myth missed a critical aspect of biology: the kidneys' job is to concentrate and eliminate waste. Just because its in high concentration in the urine doesn't mean it's concentrated in the blood.0 -
This is an interesting video:
1.13 - pH - Foundation of Wellness
The pH balance in your body is directly effected by your diet. Learn the science behind acid and alkaline diets. For more bite-sized lessons, click the Learn button.
https://wellnessworks.bloomfire.com/posts/1956-1-13-ph-foundation-of-wellness/public0 -
The pH actually ranges from 7.35 to 7.45 with an average of 7.4
Average blood bicarbonate is 25 ranging 22-28
Average CO2 dissolved in blood is 40.
Ever wonder why you get tired after eating? It's because for every bit of acid you make in your stomach, you pump equal bicarbonate into the blood. It creates an "alkaline" tide in the blood that results in feeling tired.
As far as people saying food changing pH, it can be seen in the urine quite easily but the blood is heavily buffered and it takes alot to get it out of its range.
Reason you can see it in urine is the kidneys filter and secrete acid. Meats and protein digestion results in alot of Uric and Phosphoric acid being excreted in the urine making it much more acidic than normal. Other foods can do the opposite specifically nitrate containing foods such as legumes which induce the kidneys to form ammonia and making it less acidic.
Thanks for sharing!
Is the alkaline tide measurable? As in, can you actually pick up a drop in pH in the blood? And do you know where I could find the studies that show this effect?
As for the urine... yes, I absolutely agree with you. That makes perfect sense to me.0 -
Unless you have a medical condition i have only one word to say Homeostasis!0
-
Unless you have a medical condition i have only one word to say Homeostasis!
Exactly! If you eating a well balanced diet keeps you in homeostasis, thus not overtaxing your body.
http://drbenkim.com/ph-body-blood-foods-acid-alkaline.htm0 -
Unless you have a medical condition i have only one word to say Homeostasis!
This x 11ty billion. Let's not overthink this. Your body, if you are healthy is fully capable of managing minor changes in blood pH and relatively quickly. This is really a non-issue for anyone who isn't hospitalized for other reasons.0 -
This x 11ty billion. Let's not overthink this. Your body, if you are healthy is fully capable of managing minor changes in blood pH and relatively quickly. This is really a non-issue for anyone who isn't hospitalized for other reasons.
But I LIKE to over-think things
Seriously... I get that these types of threads aren't for everyone. I didn't post it 'cause I want people to obsess over diet and blood pH. Exactly the opposite. I'd rather people stop obsessing and stop making the claim that <insert miracle food> is making their blood more alkaline.0 -
This x 11ty billion. Let's not overthink this. Your body, if you are healthy is fully capable of managing minor changes in blood pH and relatively quickly. This is really a non-issue for anyone who isn't hospitalized for other reasons.
But I LIKE to over-think things
Seriously... I get that these types of threads aren't for everyone. I didn't post it 'cause I want people to obsess over diet and blood pH. Exactly the opposite. I'd rather people stop obsessing and stop making the claim that <insert miracle food> is making their blood more alkaline.
Oh I understand the intent of your post. We're essentially saying the same thing. The fact is people mess with their blood gas way more with 15 mins of hard working out and the body brings you back into stasis quickly. So not sure why anyone would even be concerned about the pH of their food. It's a complete non issue.0 -
Oh I understand the intent of your post. We're essentially saying the same thing. The fact is people mess with their blood gas way more with 15 mins of hard working out and the body brings you back into stasis quickly. So not sure why anyone would even be concerned about the pH of their food. It's a complete non issue.
[/quote]
like!!! AMEN0 -
The normal range of blood pH is 7.35-7.45, anything outside this range will quickly lead to death if not treated immediately. Normally your body has three mechanisms to regulate blood pH, 1) blood buffer system, which consists of molecules that take up and release hydrogen atoms as needed. When the blood buffer system becomes overwhelmed the 2) lungs compensate by blowing off C02. This works to raise pH, but will lead to imbalances if done for to long. 3) The kidneys can selectively secrete or reabsorb substances as needed to maintain blood pH. These systems will always keep your pH within the normal limits unless there is a serious disease process at work preventing them from working properly. Long story short is it really doesnt matter what you eat as far a pH goes.0
-
<
dead neuron.
>.>
Has nothing to do with pH, but I was excited and had to post.
Also... I'm reading more (including the links Pu posted. Thank you for those) and there DOES seem to be a need for dietary bicarbonate, specifically in regards to maintaining bone density. Apparently, your blood will steal bicarb sometimes from the bone (and potassium and calcium) if it is short on bicarb when regulating pH. I don't know how important that is to the average person. But it's probably that this is the source of the food-regulates-blood-pH myth.
It's a good reason to eat your veggies... but as far as I can tell, it's more the biochemicals (potassium, calcium, bicarbonate) that are important and not really the acidity or alkalinity of the veggies (even though bicarb does make the veggies alkaline).0 -
This x 11ty billion. Let's not overthink this. Your body, if you are healthy is fully capable of managing minor changes in blood pH and relatively quickly. This is really a non-issue for anyone who isn't hospitalized for other reasons.
But I LIKE to over-think things
Seriously... I get that these types of threads aren't for everyone. I didn't post it 'cause I want people to obsess over diet and blood pH. Exactly the opposite. I'd rather people stop obsessing and stop making the claim that <insert miracle food> is making their blood more alkaline.
This type if thread, with the respectful, scientific discussion is awesome! Far better than a lot of the other posts here thanks for posting! 0 -
0
-
I understand all the biochemical basis for this theory because I've trained in it and I work with people who have severe acid base imbalances daily, in the real world, in life and death situations. It's my job to maintain or improve that balance in real time with CRRT, ventilator manipulation, sedation, and titrating IV infusions, internal warming and cooling methods.
The fact of the matter is, yes theoretically you can affect the acid base balance by what you eat, minimally. However, unless you are going to down an entire bottle of Tums (or two) or other intentionally caustic substances, or otherwise have comorbidities you will not disrupt the system. We're built to handle minimal disruptions, such as larger swings produced by heavy exertional activity. Comparatively speaking running at top speed for 5 mins will tax your system more than 15 meals could. Yet we recover within minutes. Your body is perfectly capable of managing a slower rise in alkalosis or acidosis produced by food. Managing these fluctuations is normal physiological activity, much like regulating body temperature.
I must strongly disagree with the notion that eating acidic or alkaline foods taxes your bones and muscles and leads to disease. I'd like to see some recent meta-analysis supporting this hypothesis. My practice is heavily reliant on empirical evidence, and I've seen nothing of any value to support this.0 -
The issue with "body pH" that is touted by some alternative medicine folk, and I do believe "alternative medicine" isn't that pie-in-the-sky in many respects, is that "body pH" could mean anything...urine, skin, blood. Urine & skin pH have huge ranges compared with blood pH. I studied metabolic acidosis in-depth when my daughter kept getting it as a preschooler. Most of the posters are dead-on, the body compensates with blood pH. I was taught in nursing school that the body cannot much survive outside of 7.35-7.45. I have seen one paint huffer show up with a blood pH of 6.3. The MD in his 20 yrs of practice had never seen a pH so acidic alive (and the pt wasn't far from dead) & ordered repeat tests two times. I don't know what became of this man, he had the most unbelievable labs you'd ever see.
You can develop metabolic acidosis when certain aspects of the kreb's cycle are ineffective. In addition, read up on the 4 complexes of mitochondrial disorder, which is within the kreb's cycle. For example, many patients with mito disorders will have elevated lactic acid in their blood, or elevated pyruvate in their blood, yet their pH be relatively normal because the respiratory system is trying to make up for it. Urine organic acids are often used to discover markers for metabolic/mitochondrial problems.
My long-winded, not-much-scientific response is to simply say, notice in these infomercials the term "body pH" being used instead of specifying blood pH. "Body pH" makes it vague and more difficult to rationally discuss, which I believe is the purpose.0 -
I understand all the biochemical basis for this theory because I've trained in it and I work with people who have severe acid base imbalances daily, in the real world, in life and death situations. It's my job to maintain or improve that balance in real time with CRRT, ventilator manipulation, sedation, and titrating IV infusions, internal warming and cooling methods.
The fact of the matter is, yes theoretically you can affect the acid base balance by what you eat, minimally. However, unless you are going to down an entire bottle of Tums (or two) or other intentionally caustic substances, or otherwise have comorbidities you will not disrupt the system. We're built to handle minimal disruptions, such as larger swings produced by heavy exertional activity. Comparatively speaking running at top speed for 5 mins will tax your system more than 15 meals could. Yet we recover within minutes. Your body is perfectly capable of managing a slower rise in alkalosis or acidosis produced by food. Managing these fluctuations is normal physiological activity, much like regulating body temperature.
I must strongly disagree with the notion that eating acidic or alkaline foods taxes your bones and muscles and leads to disease. I'd like to see some recent meta-analysis supporting this hypothesis. My practice is heavily reliant on empirical evidence, and I've seen nothing of any value to support this.
Love this post... you made some great points.0 -
The issue with "body pH" that is touted by some alternative medicine folk, and I do believe "alternative medicine" isn't that pie-in-the-sky in many respects, is that "body pH" could mean anything...urine, skin, blood. Urine & skin pH have huge ranges compared with blood pH. I studied metabolic acidosis in-depth when my daughter kept getting it as a preschooler. Most of the posters are dead-on, the body compensates with blood pH. I was taught in nursing school that the body cannot much survive outside of 7.35-7.45. I have seen one paint huffer show up with a blood pH of 6.3. The MD in his 20 yrs of practice had never seen a pH so acidic alive (and the pt wasn't far from dead) & ordered repeat tests two times. I don't know what became of this man, he had the most unbelievable labs you'd ever see.
You can develop metabolic acidosis when certain aspects of the kreb's cycle are ineffective. In addition, read up on the 4 complexes of mitochondrial disorder, which is within the kreb's cycle. For example, many patients with mito disorders will have elevated lactic acid in their blood, or elevated pyruvate in their blood, yet their pH be relatively normal because the respiratory system is trying to make up for it. Urine organic acids are often used to discover markers for metabolic/mitochondrial problems.
My long-winded, not-much-scientific response is to simply say, notice in these infomercials the term "body pH" being used instead of specifying blood pH. "Body pH" makes it vague and more difficult to rationally discuss, which I believe is the purpose.
Also very interesting... I'll probably putter around with this stuff because I'm interested in it... I'm not surprised about the mitochondrial disorders. That's one of the things that happens in brain cells when they're under oxidative stress (or other types of stresses for that matter).
And... yes... body pH vs blood pH is ... well when you say 'body' it's harder to get at the truth. Body could include the gut and the urine even though I tend to think of those as "outside" the body... a separate compartment.0
This discussion has been closed.
Categories
- All Categories
- 1.4M Health, Wellness and Goals
- 393.4K Introduce Yourself
- 43.8K Getting Started
- 260.2K Health and Weight Loss
- 175.9K Food and Nutrition
- 47.4K Recipes
- 232.5K Fitness and Exercise
- 426 Sleep, Mindfulness and Overall Wellness
- 6.5K Goal: Maintaining Weight
- 8.5K Goal: Gaining Weight and Body Building
- 153K Motivation and Support
- 8K Challenges
- 1.3K Debate Club
- 96.3K Chit-Chat
- 2.5K Fun and Games
- 3.7K MyFitnessPal Information
- 24 News and Announcements
- 1.1K Feature Suggestions and Ideas
- 2.6K MyFitnessPal Tech Support Questions