Have you heard this claim before: “Cancer cells only grow in an acidic environment, therefore you should drink alkaline water and eat an alkaline diet.”
If you have heard this before you are not alone. Literally every day in my office I get asked “hey doc, what do you think about alkaline water and alkaline diets?”
There are certainly many health claims on the internet claiming that alkaline water cures just about every medical problem (including cancer). When I hear claims like this my quack meter goes into full tilt.
If you search Google for “alkaline water” you will see many articles telling you that it’s a scam…But is it?
So, after discussing the topic of alkaline water and diets with patients for years I figured it’s about time I finally sat down and wrote a short IOE article on the subject.
Before I dive into trying to shed light on this it helps to review what is considered alkaline and acidic in terms of the diet.
- Alkaline diets are predominantly plant-based (see the chart below for specific details) as they generally have an alkaline impact on the body after they are consumed, broken down and absorbed. When all is said and done, after most plant foods are metabolized their final metabolite is bicarbonate (an alkaline compound). Alkaline water can be made by simply dissolving bicarbonate (baking soda) in water.
- In contrast, acidic diets contain a fair amount of meat, eggs and dairy (i.e. standard American diet). Most animal products are full of sulfur-containing amino acids (i.e. methionine, cysteine), which get metabolized and converted into sulfuric acid.
These are broad generalizations (there are exceptions as you can see in the chart below) but they serve as a reasonable background on the two diets. You can click on the food chart below to enlarge:
For my fellow skeptics out there: Regardless of whether there is or is not a cancer-specific effect of the acidity or alkalinity of the diet, we know that diets rich in plants are full of anticancer phytonutrients and are anti-inflammatory. Many studies have shown that consuming plant-based diets are associated with a reduced risk of cancer and cancer-related death, while diets that are heavy in animal products are more often associated with increased risks of cancer and cancer-related death.
Can Alkaline Food or Water Change Blood or Tissue Acidity or Alkalinity?
The physiology is complex, but it boils down to this:
- No matter how much alkaline water or foods you drink or eat your blood and kidneys are able to prevent significant changes in pH (a measurement of how alkaline or acidic something is) in the blood by almost instantaneously neutralizing any consumed alkaline liquids or food.
- There is one caveat: If your kidneys or lungs are not functioning properly due to disease, injury or aging they will not be able to efficiently neutralize and eliminate these alkaline or acidic chemicals. This can lead to changes in the blood and tissue pH.
- The only places you will find a significant increase in the alkalinization after you consume alkaline water or foods will be in your urine and stool, as the kidneys and intestines eliminate the majority of the alkaline molecules through these routes.
- However, some suggest (and I am starting to see the plausibility of this too) that even ‘tiny’ changes in pH may be all that is needed to make your body more or less conducive to cancer growth or progression. The pH scale is not linear but rather logarithmic (meaning a change of one pH unit corresponds to a ten-fold change in acid concentration (see pH scale). Therefore what sounds like a ‘tiny’ change in a pH value is actually a very large change in acid or alkaline concentration. Here are examples of the order of magnitude of pH change that we are talking about:
- Most humans have a venous blood pH of 7.46 (median value)
- A shift from 7.46 to 7.48 is a huge shift towards alkalosis
- A shift from 7.46 to 7.43 is an enormous shift towards acidosis
You can read much more about the science of this here.
Does Cancer Prefer To Grow In Acidic Tissues?
Yes, we have known for many years that tumors like to grow in acidic tissues.
Acidity serves as a signal to the cancer and the surrounding tissues to produce growth hormones (i.e. vascular endothelial growth factor) that instruct the body to form new tumor blood vessels (this process is called “angiogenesis”).
It is well known that if you measure the pH level around a cancerous tumor you will often discover that it is more acidic than the surrounding normal tissues. Tumors also contain areas that are more acidic than others.
Where does the acidity in and around tumors come from?
- Rapidly dividing cancer cells are very metabolically active. The main byproducts of cellular metabolism (i.e. glycolysis) are acidic molecules (i.e. carbon dioxide, lactic acid, etc.)
- The farther away cancer cells are from tumor blood vessels (see the image above) the less access they have to fresh oxygen and they have less ability for their acidic metabolic end products to leave the tissues and enter the bloodstream (leading to increased acidity).
Mouse studies have shown that when fed alkaline water (using sodium bicarbonate or baking soda) mice with cancer develop significantly fewer metastases (tumors spread around the body) compared with the mice drinking regular, non-alkalinized water.
- What is the physiologic mechanism behind this? We don’t know.
Human studies have not yet been conducted. One proposed study has a lot of potential, but the investigators decided to simply test the use of sodium bicarbonate to see if the can see tumors better. Ugh! Come on guys, your study could actually provide us with some very useful information if you are willing to look a little more deeply.
Earlier I mentioned that some folks believe that even a tiny, seemingly insignificant increase in alkalization may be all it takes to make the body less conducive to cancer growth or progression.
- We know that it is possible to induce a very small increase in alkalinization through consuming alkaline water or foods, but is that change sufficient to tip the balance in favor of reducing cancer growth or progression?
- Conversely, if you consume an acidic diet (i.e. standard American diet) might you tip the balance in favor of cancer growth?
…We simply don’t know the answers to these questions.
Additionally, as we age our kidney function begins to decline leading to a diminished capacity to maintain a normal blood and tissue pH when we consume an acidic or alkaline diet. Older individuals who consume acidic diets for many years may therefore expose themselves to a slightly more acidic tissue environment in their body.
- Might that acidic diet tip the balance of their body towards supporting cancer growth or spread?
- Might an alkaline diet (or water) reduce this risk?
…Again, we don’t know. Clearly studies in humans need to be conducted.
Acidity Increases The Growth Of ‘Bad’ Gut Bacteria:
One of the most interesting findings surrounding acidic versus alkaline diets comes from new research that found that when mice were fed water that was slightly acidic an unhealthful change in their gut bacteria developed- they had a significant increase in the growth of ‘bad’ bacteria and a decrease in their ‘good’ bacteria. This condition is called “intestinal dybiosis” and is now believed to be associated with an increased risk of developing numerous chronic inflammatory and immune related diseases (i.e. inflammatory bowel diseases, diabetes, obesity, colorectal cancer, etc.)
You can read more about dysbiosis and cancer in my recent blog.
One of the explanations for how intestinal dysbiosis causes so many deleterious health effects stems from the fact that the ‘bad’ bacteria make the intestinal lining inflamed and leaky (called “leaky gut”) enabling undesirable foreign substances (i.e. carcinogens, toxins, bacteria, food antigens) to be able to more easily enter the blood stream and wreak havoc throughout the body over time through chronic inflammatory and immune reactions.
- A good example of this comes from the above mentioned study, in which the mice that developed dysbiosis from drinking acidic water were found to have a significantly higher risk of developing type-1 diabetes (resulting from immune system activation against the pancreas).
Even if there is no benefit derived from the alkaline metabolites in a plant based diet, studies clearly show that if you eat a diet rich in plant foods you will not only increase the growth and balance of your ‘good’ intestinal bacteria but you will also reduce your risk of developing and dying from cancer and other chronic diseases.
The Bottom Line:
We have absolutely no idea if consuming alkaline foods or water reduces the risk of cancer development, growth or progression in humans.
This is what we do know:
- Tumors create their own acidic environments in which the acidity serves as a powerful growth signal telling the body to create new tumor blood vessels.
- When mice with cancer are fed alkaline water they have much lower rates of metastatic disease (cancer spread across the body).
- Plant based diets and alkaline water subtly change the blood pH making it slightly more alkaline.
- Consuming a plant based diet, rich in anticancer phytonutrients, is associated with lower rates of many chronic diseases and cancers.
There is only an upside to making the anticancer lifestyle change of incorporate a diet rich in plant foods (which happen to be alkaline) and lower in animal products (which happens to be acidic).
In terms of adding alkalinized water to the daily routine, I see few downsides unless you have kidney disease which can make it risky to consume too much alkaline water.
- But please don’t spend thousands of dollars on an expensive alkalinizing water machine. To me that is a scam when you can simply add 3/4 of teaspoon of baking soda to a liter or quart of filtered water for the same result.
Based on the limited information we know, I would say that it is plausible that an alkaline diet or water could be an additive factor (in addition to other lifestyle modifications) that may help to support an anticancer environment in the body.
Clearly human studies need to be done to determine what if any effect might be attributable to healthful changes in gut bacteria, reduced production of tumor blood vessel growth factors, reduced metastases or simply due to the fact that alkaline foods tend to be less inflammatory and full of anticancer phytonutrients.
Schedule an integrative oncology consult with me today to find out what you can do to make your body less conducive to cancer development, growth and progression. It’s not all about your pH. There’s much more to it.