Not Harmful At All Series No3.
Stepped down from several works of Dr Chris Kresser, namely :
*What is the alkaline hypothesis?
* Why the Acid-Alkaline Theory is a Myth.
*The Acid-Alkaline Myth: Parts 1. &2,etc.
Now, take it( Excerpts only)
On Acid - Alkaline "Ash".
"’.... the basic claim is that the foods we eat leave behind an ‘ash’ after they are metabolized, and this ash can be acid or alkaline (alkaline meaning more basic on the pH scale).
... According to this theory , it is in our best interest to make sure we eat more alkaline foods than acid foods, so that we end up with an overall alkaline load on our body.
This will supposedly protect us from the diseases of modern civilization, whereas eating a diet with a net acid load will make us vulnerable to everything from cancer to osteoporosis.
To make sure we stay alkaline, they recommend keeping track of urine or saliva pH using handy pH test strips....'
Fact Number One:
Yes, Foods CAN INFLUENCE our urine pH! No doubt!
"... Before I start dismantling the above theory, I want to acknowledge a couple of things they got right:
I. In general, animal products and grains are acid forming, while fruits and vegetables are alkali forming.
ii. Pure fats, sugars, and starches are neutral, because they don’t contain protein, sulfur, or minerals.
iii. Foods do leave behind acid or alkaline ash. The type of ‘ash’ is determined by the relative content of acid-forming components such as PHOSPHATE and SULPHUR, and ALKALIS, such as CALCIUM, MAGNESIUM, and POTASSIUM.
iv. It’s also true that the foods we eat change the pH of our urine, but urine pH is not a good indicator of the overall pH of the body, nor is it a good indicator of general health...."
Fact Number Two:
No!, Foods DON'T INFLUENCE our blood pH. Never!
"...Proponents of the alkaline diet have put forth a few different theories about how an acidic diet harms our health. The more ridiculous claim is that we can change the pH of our blood by changing the foods we eat, and that acidic blood causes disease while alkaline blood prevents it....
This is not true!! Why?
...The body tightly regulates the pH of our blood and extracellular fluid, and we cannot influence our blood pH by changing our diet... regardless of what you eat or what your urine pH is, you can be pretty confident that your blood pH is hovering around a comfortable 7.4!..."
Note: However, a state of acidosis can be caused by pathological conditions such as chronic renal insufficiency, not by whether you choose to eat a salad or a burger..."
Will eating an alkaline diet make you and your bones healthier? Not likely!
On Acid-ash hypothesis of osteoporosis?
"...A more nuanced claim has been proposed specifically regarding bone health, and this hypothesis is addressed somewhat extensively in the scientific literature. It supposes that in order to keep blood pH constant, the body PULLS MINERALS FROM THE BONES to neutralize any excess acid that is produced from our diet. Thus, net acid-forming diets (such as the typical Western diet) can cause bone demineralization and osteoporosis. .
"...Nothing can be further from the truth!
See!: The kidneys – not bone – regulate blood pH...the acid-ash hypothesis seems to completely disregard the vital role the kidneys play in regulating body pH.
The kidneys are well equipped to deal with ‘acid ash.’ When we digest things like protein, the acids produced are quickly buffered by bicarbonate ions in the blood. This reaction produces carbon dioxide, which is exhaled through the lungs, and salts, which are excreted by the kidneys. During the process of excretion, the kidneys produce ‘new’ bicarbonate ions, which are returned to the blood to replace the bicarbonate that was initially used to buffer the acid. This creates a sustainable cycle in which the body is able to maintain the pH of the blood, WITH NO INVOLVEMENT OF BONES WHATSOEVER...
...Thus, our understanding of acid-base physiology DOES NOT SUPPORT THE THEORY that net acid-forming diets cause loss of bone minerals and osteoporosis. ...
What the Studies say.
".... even though the hypothesis holds that higher intakes of protein and phosphate are acidifying and therefore detrimental to bone health, multiple studies have shown that increasing protein or phosphate intake has POSITIVE effects on calcium metabolism and on markers for bone health....
... Summarizing the clinical evidence, two different meta-analyses and a review paper all concluded that randomized controlled trials do not support the hypothesis that acidifying diets cause loss of bone mineral and osteoporosis.
... For example, there’s a 2009 trial in the American Journal of Clinical Nutrition that found that in postmenopausal women, increasing protein from 10% of calories to 20% of calories improved intestinal calcium absorption and also decreased urinary DPD, which is a marker of bone breakdown, and an increased IGF-1, which, .. has several different positive effects on bone health.
....there was a really exhaustive review on this topic published in the Nutrition Journal in 2011 that looked at 55 different trials, 22 of them randomized clinical trials, and the authors’ conclusion was this: “A causal association between dietary acid load and osteoporotic bone disease is not supported by the evidence, and THERE IS NO EVIDENCE that an alkaline diet is protective of bone health. .
... Hopefully I’ve given you a decent understanding of how our bodies handle pH balance, and have reassured you that you don’t need to worry about the ACIDITY OF YOUR URINE with regards to bone health"
How about other diseases?
Dr Chris Kresser continues. Excerpts still:
"... In Part 1 of this series, I talked about why the basic premise of the acid-alkaline theory is flawed, and I showed that the evidence doesn’t support the idea that a net acid-forming diet is harmful to bone health.
Now I want to look at the effect of dietary acid load on other health conditions., like Muscle wasting, Cancer, Hypertension, Diabetes,etc.
I. On Muscle Wasting
" There is some research claiming that acid-forming diets cause muscle wasting, and the proposed mechanism is similar to that of the acid-ash hypothesis of "calcium loss" (osteoporosis)
Some researchers hypothesize that in order to eliminate excess acid and maintain homeostasis, the KIDNEYS MUST STEAL AMINO ACIDS from muscle tissue...
... Yes, Just as a higher acid load increases calcium in the urine, it also increases nitrogen in the urine, leading some to believe that an acid-forming diet causes net nitrogen loss.
However, some of these studies neglect to measure nitrogen balance, so this is not necessarily true....
This theory also does not acknowledge that protein, although it’s acid forming, actually INCREASES THE BODY'S ABILITY to excrete acid.
Finally, the one observational study concluding that alkaline diets improve lean muscle mass DIDN'T EVEN MEASURE the overall acid load of the diet.
Instead, they used potassium intake as an approximate measure, and just assumed that the observed improvement in muscle mass was due to the diet being more alkaline... This is not correct."
II. On Cancer
"... One of the more popular claims of the alkaline diet is that it can cure cancer.
Proponents say that because cancer can only grow in an acidic environment, a net-alkaline diet can prevent cancer cells from growing, and can eliminate existing cancer cells.
This theory is incorrect for a few reasons.
1. First of all, the hypothesis depends on the ability of food to substantially change the pH of the blood and extracellular fluid, which I’ve already shown is not the case.
2. Second, cancer is perfectly capable of growing in an alkaline environment.
The pH of normal body tissue is 7.4, which is slightly alkaline, and in almost every experiment done with cancer cells, they are grown in an environment at that pH.
Now, cancer cells do tend to grow better in an acidic environment, but the causality is reversed. Once a tumor develops, it creates its own acidic environment through up-regulated glycolysis and reduced circulation, so the pH of the patient’s blood NO LONGER determines the pH of the cancer....
A Fact: It’s not the acidic environment that causes the cancer; it’s the cancer that causes the acidic environment....
III On Other Effects
There are a few observational studies attempting to link acid-forming diets with hypertension, but the results are mixed.
There’s also limited observational data associating higher acid loads with things like high cholesterol, obesity, and insulin resistance, but THERE ARE NO PROPOSED MECHANISMS OR CLINICAL STUDIES to validate the hypotheses.
... If you read these papers, you’ll notice that whenever they cite trials showing the deleterious effects of acidosis, those trials were done on patients with chronic kidney disease or diabetes-induced acidosis.
In the studies done on healthy people, they’re given ammonium chloride to induce acidosis.
What you won’t see are clinical trials showing health consequences from purely ‘diet-induced’ acidosis. (Perhaps because 'DIET - INDUCED' ACIDOSIS DOES NOT EXIST!)
" I don’t deny that many people have seen significant health improvements when switching to an "alkaline diet", but there are many possible reasons for this NOT HAVING TO DO with pH balance, namely:
1. Eating more fresh produce is
rarely a bad idea, especially when it displaces nutrient poor processed foods. 2. A person switching to an alkaline diet would significantly reduce their consumption of grains , which could cause dramatic health improvements for somebody with a leaky gut or gluten sensitivity.
3. Dairy would also be minimized, which would help those with dairy sensitivities.
4. And although pure sugar isn’t an acid-forming nutrient, many lay people claim that it is, so alkaline diets tend to contain far less sugar than a standard Western diet...."
Warning! ... If you try to maximize the alkaline-forming quality of the diet, then you’ll pretty much be eschewing all animal proteins. And if you do that, you’re going to put yourself at higher risk for things like B12 deficiency, calcium deficiency, zinc deficiency, vitamin D deficiency, EPA and DHA deficiency, and all of the health problems that are associated with that..."
But, Please Note: ... For those with renal failure or similar conditions that affect kidney function, it’s a different story—there’s certainly room for manipulation of urine pH in the treatment of those conditions.
But for someone with functioning kidneys, there should be NO CONCERN THAT ACID - FORMING DIET WILL HARM HEALTH ...."
End of Discussion, from Dr Kresser.
With these "OUR" few points..(as "Debates" normally end!), we can safely say that:
Between the scientific evidence (or lack thereof) and the anthropological research, we can be confident that the acid load of our diets DOESN'T NEGATIVELY IMPACT HEALTHY PEOPLE. I rise!
Editor's Addendum: Included here is the book "pH Miracle"(written by Dr Robert Young decades ago), which, effectively, created the Acid - alkaline " Market"
Also showcased are a plethora of other books, gadgets & products spawn solely by the same ALKALINE " Business".
Are they still relevant?