Proponents of the alkaline diet claim that eating certain foods influences the body’s acid-base homeostasis, or pH levels. It’s believed that encouraging a healthy, pH balanced environment within the body can produce favorable effects on one’s health. It sounds like a good idea, and it is true that tissues and fluids must maintain a certain pH level to function properly. However, your body has mechanisms to keep pH levels in check — regardless of what you eat. Let’s take a closer look at the alkaline diet and break it down.
Much of the discussion surrounding the alkaline diet focuses on the significant changes in the human diet over the last 10,000 years. Until a recent point on our evolutionary timeline, humans mostly consumed fruit, vegetables, and small amounts of lean protein. Once the food industry came into existence, we began eating more refined grains, fattier sources of meat, and processed foods that are high in sodium, saturated fat, and refined sugars — all of which cause inflammation and contribute to serious, chronic diseases. The alkaline diet discourages such foods.
If you’re researching the alkaline diet, you may have noticed some sources describe it using lofty words like “miraculous.” In reality, there are many variables, diet-related and otherwise, that affect your health. In many ways, the alkaline diet is excellent. It’s balanced and encourages the consumption of raw fruits and vegetables. It’s definitely a healthy plan that may reduce your risk of developing chronic, diet-related diseases. But, does it live up to all the claims?
What Is the Alkaline Diet?
Also called the acid-ash diet, the alkaline diet promotes foods alleged to influence acid-base homeostasis in the body. Specifically, whole, raw, organic fruits and vegetables. These foods are thought to produce a “net alkaline effect.” Advocates of the diet say that an alkaline environment within the body helps weight loss efforts, increases energy, and can boost the immune system. However, despite its popularity, the data has not substantiated such claims. In actuality, it’s difficult to say if the alkaline diet has any real effect on the body’s pH balance.
How pH Affects Your Health
To understand how the body’s internal pH levels affect your health, it helps to have an elementary understanding of what pH is. The pH scale runs from 0 (acidic) to 14 (basic or alkaline); 7 is neutral. Pure water has a pH of 7. Sulphuric acid has a pH of almost 0, and is both extremely acidic and highly corrosive. At the opposite end of the scale, lye has a pH of nearly 14. Lye is also highly corrosive, but that’s because it’s extremely alkaline. The acidity or alkalinity of a substance can be balanced with a buffer that resists changes in pH. Alternatively, you can add a substance with a pH on the opposite side of the scale to try and get closer to a pH of 7; i.e. adding a base to an acid, or vice versa.
The human body needs to maintain a pH in a narrow range, between 7.35 and 7.45, to function properly. This pH range provides the ideal working environment for the body’s fluids and tissues. Your stomach is acidic, about 3.5 on the pH scale, and it must remain so in order to break down food. Blood is mostly neutral—a characteristic that enables it to transport various substances around the body without affecting or reacting to them.
The wrong pH in a given system or organ can seriously affect your health. For instance, the inside of your stomach is lined with a thick layer of mucus that protects it from being digested along with your lunch. But, the small intestine isn’t as well protected. Instead, alkaline bile is released into the small intestine to buffer and balance the acidity of the gastric acid secreted from the stomach.
Health and the Body’s pH
Clearly, proper pH is critical to your health and an extreme pH imbalance can be fatal. Alkalosis occurs when your blood and other fluids become too alkaline. It’s a condition that can be caused by liver or lung disease, low oxygen levels, or a sudden loss electrolytes. Symptoms include confusion, lightheadedness, twitching and spasming muscles, seizure, tingling in the extremities and face, and respiratory distress.
Conversely, acidosis is characterized by a high acid load in the body’s fluids. There are several different types of acidosis: metabolic, respiratory, lactic, and renal (kidneys). Symptoms include confusion, fatigue, shortness of breath, and lethargy. Metabolic acidosis is the one you usually hear about with regard to the alkaline diet, but there are other causes of the disorder, such as kidney disease and dehydration.
Diet-induced metabolic acidosis results when too many animal products, and not enough fruits and vegetables, are consumed. Metabolic acidosis increases your risk of developing cardiovascular disease, diabetes, insulin resistance, and kidney stones. It causes kidney damage, which contributes to metabolic acidosis.
How Your Body Compensates for Unbalanced pH Levels
The kidneys are one of the body’s primary defenses against acidosis. They accomplish this by sending excess metabolically-produced acids to your bladder to be eliminated via urine. They also maintain tight control over bicarbonate, which can act as either a base or an acid depending on what it reacts with. When kidney function is compromised the body is less equipped to control its acid load, which leads to an even higher acid load. This condition may worsen with age if kidney function continually decreases.
The ability of the kidneys to filter acid is not the body’s only mechanism to control its acid load; the lungs assist as well. Carbon dioxide is a product of cellular metabolism and it becomes acidic in the blood. The lungs are able to increase or reduce respiratory function to maintain acid-base homeostasis.
What Makes a Diet Alkaline?
According to the acid-ash theory, certain foods allegedly promote either alkalinity or acidity in the body. Cruciferous vegetables are supposed to be among the best options for promoting alkalinity. Peas, berries, citrus fruits, and melons are also supposed to be base-producing. Processed oils, nuts, refined grains, alcohol, and animal protein are believed to have a net acidic effect.
Top 10 Alkaline Forming Foods
- Mustard Greens
- Apple Cider Vinegar
- Pumpkin Seeds
- Green Tea
Top 10 Acid Forming Foods
- Peanut Butter
- White Pasta and Bread
- Corn Oil
- Beer & Hard Liquor
Measuring the Diet’s Results
The acid-ash hypothesis asserts that our bodies steal calcium from our bones to restore acid-base homeostasis when blood becomes too acidic. Advocates claim its success can be determined by examining the pH of urine. It’s true that the food you eat changes the pH of your urine. Meats and cheeses, for example, make it more acidic, while fruits and veggies make it less.
However, research doesn’t support the totality of this hypothesis. Yes, it’s true that eating a very acidic diet will cause your kidneys to excrete more acid, but that doesn’t necessarily reflect the pH levels within your body.[14, 15] A study published in the British Journal of Nutrition suggests urine pH is an unreliable measurement. Urine tests only reveal how much acid you’ve excreted. They don’t provide complete information on the internal pH levels throughout your body. You have a lot of different fluids in your body and they all have different pH levels. Urine pH can range from 4.6 to 8; blood typically hovers around 7.4.
Does the Alkaline Diet Work?
To determine if a diet “works,” it’s important to establish the specific goals and indicators of success. Is it an attempt to lose weight? Feel more energetic? Build muscle?
From a purely nutritional standpoint, the alkaline diet is strong. It centers heavily around fruits and vegetables, rather than meat and grains. Researchers suggest the absence of plant foods, excessive consumption of meat, saturated fat, simple sugars, and starchy foods contributes to many common health problems.[18, 19] Any diet that includes more health-promoting foods will better support your health than a diet that doesn’t. However, eating healthy, natural foods, may not change your internal acid levels, which is the entire point of the alkaline diet.
Unintentional Benefits of the Diet
The foods you eat may alter the pH of your urine, but they do little to alter your body’s pH otherwise. But, the alkaline diet does offer some good dietary recommendations. A Tuft’s University study of 400 men and women over 65 who followed the alkaline diet revealed that one explanation may simply be the potassium content of healthy foods, rather than any net alkaline load. Those who ate potassium-rich fruits and vegetables had more lean muscle mass than the control group after the conclusion of the trial.
Many of the foods recommended by the alkaline diet are nutrient-dense, low-calorie alternatives to traditional dietary choices. The diet promotes eating mostly organic plant-based foods high in vitamin C, selenium, iron, and zinc; all of which support gut health and the immune system. Sweet red peppers, broccoli, and carrots promote healthy skin due to their high concentrations of vitamin A.
When you avoid foods high in omega-6 fatty acids, you reduce your levels of arachidonic acid, which causes the inflammation associated with heart disease and joint pain. The alkaline diet also encourages you to avoid processed foods and refined sugars; neither offer any nutritional benefits and both are common causes of diet-related diseases.
The Role of Proper Nutrition in a Healthy Life
The “efficacy” of the alkaline diet may have little to do with pH levels and more to do with the many benefits of eating whole, organic food. In fact, nutrition affects gut health and overall wellness more than any other factor. Combining solid, consistent nutrition with regular body cleansing will help your body be its best. If you’re looking for a plan for healthy eating, I recommend the Body Cleansing Diet. It encourages raw, organic fruits and vegetables, like the alkaline diet. It wasn’t intentional, but many of the foods recommended by the alkaline diet also happen to be the best for cleansing and nourishing your body.
No matter what you eat, remember that a diet isn’t a “lose twenty pounds and quit” kind of commitment. A proper “diet” is part of your lifestyle. You can’t do it for three months then go back to eating unhealthy food.
Have tried the alkaline diet? What did you think? Leave a comment below and share your thoughts.
by Dr. Edward Group DC, NP, DACBN, DCBCN, DABFM
- “What is PH.” Brooklyn College. Brooklyn College, n.d. Web. 24 Mar. 2016.
- Jew S1, AbuMweis SS, Jones PJ. Evolution of the human diet: linking our ancestral diet to modern functional foods as a means of chronic disease prevention. J Med Food. 2009 Oct;12(5):925-34. doi: 10.1089/jmf.2008.0268.
- Sebastian A1, Frassetto LA, Sellmeyer DE, Merriam RL, Morris RC Jr. Estimation of the net acid load of the diet of ancestral preagricultural Homo sapiens and their hominid ancestors. Am J Clin Nutr. 2002 Dec;76(6):1308-16.
- “What Is pH?” EPA.gov. United States Environmental Protection Agency, 22 Feb. 2016. Web. 24 Mar. 2016.
- Waugh A, Grant A. Anatomy and Physiology in Health and Illness. 10th edition. Philadelphia, Pa, USA: Churchill Livingstone Elsevier; 2007. Print.
- Policy, Privacy, et al. A primer on pH. n.d. Web. 3 Oct. 2016.
- “Alkalosis.” 28 Sept. 2016. Web. 3 Oct. 2016.
- “Acidosis.” 28 Sept. 2016. Web. 3 Oct. 2016.
- Adeva, MM, and G Souto. “Diet-Induced Metabolic Acidosis.” Clinical nutrition (Edinburgh, Scotland). 30.4 (2011): 416–21. Web. 3 Oct. 2016.
- “Diet-Induced Metabolic Acidosis.” Clinical nutrition (Edinburgh, Scotland). 30.4 (2011): 416–21. Web. 3 Oct. 2016.
- Hamm, Lee L., Nazih Nakhoul, and Kathleen S. Hering-Smith. “Acid-Base Homeostasis.” 10.12 (2015): n.pag. Web. 3 Oct. 2016.
- “A list of Acid / Alkaline Forming Foods.” 2011. Web. 26 Sept. 2016.
- Remer, Thomas, and Friedrich Manz. “Potential Renal Acid Load of Foods and Its Influence on Urine pH.” Journal of the American Dietetic Association 95.7 (1995): 791-97. Web.
- Fenton, TR, et al. “Meta-Analysis of the Effect of the Acid-Ash Hypothesis of Osteoporosis on Calcium Balance.” Journal of bone and mineral research : the official journal of the American Society for Bone and Mineral Research. 24.11 (2009): 1835–40. Web. 3 Oct. 2016.
- Saito, M., and K. Marumo. “Collagen Cross-links as a Determinant of Bone Quality: A Possible Explanation for Bone Fragility in Aging, Osteoporosis, and Diabetes Mellitus.” Osteoporosis International Osteoporos Int 21.2 (2009): 195-214. Web.
- Bonjour, Jean-Philippe. “Nutritional Disturbance in Acid–base Balance and Osteoporosis: A Hypothesis That Disregards the Essential Homeostatic Role of the Kidney.” British Journal of Nutrition Br J Nutr 110.07 (2013): 1168-177. Web.
- Brooks, David W. “Ph Of The Blood – Control Mechanisms.” University of Nebraska–Lincoln. University of Nebraska–Lincoln, n.d. Web. 12 Mar. 2016.
- Katz DL. Plant Foods in the American Diet? As We Sow…. The Medscape Journal of Medicine. 2009;11(1):25.
- Guenther, Patricia M., Kevin W. Dodd, Jill Reedy, and Susan M. Krebs-Smith. “Most Americans Eat Much Less than Recommended Amounts of Fruits and Vegetables.” Journal of the American Dietetic Association 106.9 (2006): 1371-379. Web.
- De Santo, NG, G. Gapasso, G. Malnic, P. Anastasio, L. Spitali, and A. D’Angelo. “Effect of an Acute Oral Protein Load on Renal Acidification in Healthy Humans and in Patients with Chronic Renal Failure.” Journal of the American Society of Nephrology 8.5 (1997): 784-92. Web. 24 Mar. 2016.
- “Plant foods for preserving muscle mass: USDA ARS.” 8 Dec. 2016. Web. 14 Sept. 2016.
- Kirkpatrick, Kristin, MS, RD, LD. “Eat These Foods to Boost Your Immune System – Health Essentials from Cleveland Clinic.” Health Essentials. Cleveland Clinic, 15 Jan. 2015. Web. 24 Mar. 2016.
- Pappas, Apostolos. “The Relationship of Diet and Acne: A Review.” Dermato-endocrinology 1.5 (2009): 262–267. Print.
- Sears, Barry, and Camillo Ricordi. “Anti-Inflammatory Nutrition as a Pharmacological Approach to Treat Obesity.” Journal of Obesity 2011 (2011): 431985. PMC. Web. 24 Mar. 2016.