The idea that acid-alkaline balance in the body can affect health has been around for many decades. According to this theory, our modern American diet makes our bodies more acidic. A more acidic body, in turn, will lead to chronic diseases such as cancer and heart disease. But does this theory hold water? Why would being “acidic” be so bad? Is there anything you can do to address the problem? It’s true: in some cases being too acidic can indeed kill you! Just not in the way you think.
The idea that acid-alkaline balance in the body can affect health has been around for many decades. According to this theory, our modern American diet makes our bodies more acidic. A more acidic body, in turn, will lead to chronic diseases such as cancer and heart disease. But does this theory hold water?
Consider the example of cancer. A Google search on the phrase “acid diet cancer,” will give you a listing of 1.9 million links. Search “diet acid cancer” and the number of links jumps to 6.6! Clearly, this is a hot topic. Unfortunately, hot does not always equal true.
Working in Reverse
As with most nutrition myths, there is a grain of truth regarding cancer and acid. But the concept that cancer is caused by an “acid body” comes from a misreading of the science. In fact, it comes from reading the science backwards.
Cancer cells can create acid. This may cause a small area in and around cancer cells, called the microenvironment, to become more acidic (1-3). But this process does not necessarily make the entire body more acidic.
Saying that an acidic environment causes cancer is sort of like saying, “Bonnie is a nurse. Therefore, all nurses are named Bonnie.” Obviously, that’s ridiculous. Science simply cannot work in reverse. Flipping the cancer-acid relationship around is not good science.
Do You Have a Knowledge Base on Acid?
Our bodies regulate acidity within a very tight range. Normal blood acidity levels range between a pH of 7.35 and 7.45 (4). A pH of 7.0 is completely neutral. It is neither acidic nor alkaline. A pH below 7.0 is acidic. The lower the number, the more acidic a substance is. A pH above 7.0 is alkaline. The higher the number, the more alkaline a substance is. This means that blood, at pH 7.35 to 7.45, is slightly alkaline, or “basic.”
The body can become dangerously acidic (acidosis) or far too alkaline (alkalosis). What happens when our pH is knocked out of the healthy range? In a word, it’s mayhem.
When people experience acidosis or alkalosis, they are very, very sick. They may even need the help of a respirator to breathe and a dialysis machine to function for their kidneys. They may be in a coma. I have spent time in an intensive care unit (ICU), working with patients who were experiencing acidosis or alkalosis. Believe me, it’s nothing any of us ever want to experience.
When I began working with people with chronic disease concerns, I learned about the myth of body acidity as a cause of disease. I was intrigued. Moreover, I was amazed that anyone would attempt to dramatically alter the acid-alkine (base) balance of his or her body, because doing so is such a bad idea!
Does Your Diet Pass the Acid Test?
Is it a good idea to nudge the body toward the less acidic end of normal? There is no evidence that this will reduce chronic disease, but it won’t hurt. And it just so happens that the foods that make the body less acidic are the same foods that fight disease. You won’t be surprised to learn I’m talking about plants.
One effective way to decrease acidity in the body, albeit slightly, is to eat more plants. In general, plant foods, especially vegetables and fruit, make the body less acidic. Meat and protein foods tend to make the body more acidic. This can be measured in the blood and urine. In fact, vegetarians have less acidic urine than people who eat meat (5).
Bear in mind that while eating more plants can decrease acidity in the body, we don’t know that decreasing acidity actually does anything to prevent disease. Fortunately, we do know eating plants is good for our bodies in other ways.
From Acid to Alkaline
When thinking about acid-alkaline balance, don’t be fooled by the acidity of the food itself. Some very acidic foods, such as oranges and other citrus fruit make the body less acidic. Due to complicated body chemistry, acidic foods often do not create acid in the body.
Also keep in mind that most vegetables and fruit decrease acid production in the body, but a few can increase it. I’m sure by now you’ve figured out that I wouldn’t recommend you avoid these “acid producing” plants. It’s really more of a curiosity than anything else. But it’s worth mentioning before I give you the following list of acid and alkaline foods (6).
Make the Body More Acid
|Meat||All meat (beef, chicken, pork, lamb), fish, fowl (duck, goose), shellfish, eggs, all types of cheese, peanut butter, peanuts|
|Fats||Bacon, nuts (brazil nuts, filberts (hazel nuts), walnuts)|
|Starch||All types of bread, cereal, crackers, pasta, noodles|
|Fruits||Cranberries, plums, prunes|
|Sweets||Plain cakes, cookies|
Make the Body Less Acid (More Alkaline)
|Milk||Milk and milk products, cream, buttermilk|
|Fats||Nuts (almonds, chestnuts, coconut)|
|Vegetables||All types (except corn & lentils); especially good are beets, beet greens, Swiss chard, dandelion greens, kale, mustard greens, spinach, turnip greens|
|Fruits||All types (except cranberries, plums, prunes)|
|Fats||Butter, margarine, cooking fats, oils|
|Sweets||Plain candies, sugar, syrup, honey|
Food for Thought
In the end, being “less acid” may not have much of an impact on your health, but here’s something interesting to consider. Researchers are studying how we might improve cancer treatments by changing the acidic microenvironment in tumors using medications and other techniques. The latest data suggest that increasing cancer cell acidity will cause those cells to self-destruct (7)!
- Tong Z, Luo W, Wang Y, Yang F, Han Y, Li H, et al. Tumor tissue-derived formaldehyde and acidic microenvironment synergistically induce bone cancer pain. PLoS One. 2010;5:e10234.
- Schornack PA, Gillies RJ. Contributions of cell metabolism and H+ diffusion to the acidic pH of tumors. Neoplasia. 2003;5:135-45.
- Webb SD, Sherratt JA, Fish RG. Mathematical modelling of tumour acidity: regulation of intracellular pH. J Theor Biol. 1999;196:237-50.
- Merck Manual Online. Disorders of Nutrition and Metabolism. Acid-Base Balance. Accessed June 6, 2010. Available at: https://merck.com/mmhe/sec12/ch159/ch159a.html.
- Dwyer J, Foulkes E, Evans M, Ausman L. Acid/alkaline ash diets: time for assessment and change. J Am Diet Assoc. 1985;85:841-45.
- Wilkens KG. Nutritional Care In Renal Disease. In: Mahan LK, Escott-Stump S, eds. Krause’s Food, Nutrition, & Diet Therapy. 9th ed. Philadelphia, PA: W.B. Saunders Company; 1996:771-803.
- Laihia JK, Kallio JP, Taimen P, Kujari H, Kähäri VM, Leino L. Protodynamic Intracellular Acidification by cis-Urocanic Acid Promotes Apoptosis of Melanoma Cells In Vitro and In Vivo. J Invest Dermatol. Published online ahead of print. Jun 3, 2010.