What You Should Know About the Alkaline Diet Before You Try It

Updated: Dec. 13, 2021

A-listers like Jennifer Aniston, Gwyneth Paltrow, and Kelly Ripa are big fans of the alkaline diet: What exactly is it and can this way of eating really promote weight loss and prevent cancer?


What is an alkaline diet?

The alkaline diet’s premise is this: Replace acidic foods with alkaline foods and your health will improve. Why would that work, you ask? The theory is that by controlling your body’s pH level (pH is a scientific scale on which acids and bases are measured), you can lose weight and avoid chronic diseases like cancer and heart disease. Also a consideration in some skin care routines, pH levels are measured on a scale from 1 to 14; under seven are the more acidic foods like vinegar, animal fats, and dairy. Over seven are alkaline foods—these mostly include healthful, plant-based foods. When you digest a food, the leftover residue is ash, which can be acidic or alkaline. This is why the alkaline diet is sometimes called the alkaline ash diet. According to proponents of the alkaline diet, acidic ash can be dangerous to your health. By the way, this is what alkaline water does to your body.

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Can changing my diet affect my pH levels?

Yes and no. Many experts are quick to point out that you can’t change the pH in your blood by what you eat. “The body is very well tuned to keep the proper pH level throughout—more acidic in the stomach, more neutral or alkaline in the blood—but the body does this on its own and no evidence indicates that diet has much impact, other than short-term during digestion,” says Connie Diekman MEd, RD, LD, FADA, director of University Nutrition at Washington University in St. Louis past president of the American Dietetic Association (now the Academy of Nutrition and Dietetics). You can change the pH of your urine, but urine pH fluctuates quickly and easily and is influenced by many factors other than diet. It is also possible to change the pH level of your saliva by what you eat.

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Is the alkaline diet healthy?

Processed meats rank high on the list of foods cancer doctors never eat, and are also frowned upon in an alkaline diet because of their high acidity. “An alkaline diet is one that tries to balance the pH level of the body by increasing consumption of alkalizing foods, such as fruits and veggies, and reducing/eliminating most acidic foods, such as processed meats and refined grains,” explains says Josh Axe, DNM, author of Eat Dirt and co-founder of Ancient Nutrition. These are the best and worst days to start a diet, according to science.


Will I lose weight on an alkaline diet?

Yes, but it’s not magic, says Diekman. “An alkaline diet can lead to weight loss since it limits many higher calorie foods and focuses on lots of fruits and vegetables,” she says. There’s a catch. “The problem is that it is extreme in what you must avoid making it hard to follow the diet in the real world and it can lead to nutrient gaps due to the elimination of foods that it classifies as too acidic.” If you are trying to lose weight, these tiny diet changes can help.

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Is an alkaline diet good for teeth?

Smile-friendly alkaline foods raise the pH level in your mouth via saliva and may improve your oral health as a result. Smile-challenging foods are acidic can erode your teeth. Live with acid reflux? If so, this may also affect the health of your smile. That’s the main message of a study in General Dentistry, which linked acid reflux to the erosion of tooth enamel. See a dentist if you are concerned.

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Can an alkaline diet improve bone health?

Many alkaline diet state that consuming a lot of acid-forming foods can causes calcium to be leached out of bones to maintain the body’s pH balance. This is true-ish, experts say. Calcium is a base, which neutralizes acidity. The more acid you consume or make, the more calcium (base) you need to neutralize it, but many other factors play a role in how and when calcium is released from bones. There is no hard-and-fast evidence that an alkaline diet protects the bones, but certain foods and beverages that are restricted on this diet do in fact decrease calcium absorption and lead to bone loss, namely caffeine and alcohol, according to the National Osteoporosis Foundation.


Can an alkaline diet improve heart health?

There are many habits that can make for a heart-healthy day, and eating a diet that is largely plant-based (like the alkaline diet) is known to be good for the heart. The alkaline diet is also low in animal protein and processed meats which are loaded with sodium and can increase blood pressure in some people. The alkaline also eliminates such waistline saboteurs as processed foods and sweets. High blood pressure and obesity are major risk factors for heart disease. These are the best and worst diets for heart health.


Can an alkaline diet lower cancer risk?

Many cancer-fighting foods are also alkaline diet foods, but at this point, there is no evidence for or against the role that an alkaline diet can play in cancer prevention. A plant-based diet, however, is believed to help lower risk for cancer and is even recommended for cancer survivors, according to the American Cancer Research Institute. New research out the University of Alabama at Birmingham shows that a plant-based diet may make it easier to treat one of the more the most lethal breast cancers. Though the evidence is a bit conflicting: Certain chemotherapy drugs kill more cancer cells in an alkaline environment and others work better in an acidic one, according to a review study in the Journal of Environmental Public Health. This is something to discuss with your doctor if you are being treated for cancer.


Will an alkaline diet improve back pain?

There are many surprising causes of back pain, and an acid-rich diet may be one of them. In fact, a study of 82 people with chronic low back pain showed that those who took an alkaline supplement that contained magnesium had less pain than their counterparts who didn’t. This alkaline mineral neutralizes the acid and helps muscles relax and may relieve pain as a result. Learn about the best diet for every decade of life.


Getting started on an alkaline diet plan

Add at least some fresh fruits and veggies to all your meals and snacks, Axe says. Try a “meatless Monday” as you aim for more plant-based protein and less meat, especially processed meats. Lower your intake of sodium from processed, canned or frozen foods. Add pH drops, fresh lemon or lime juice, or even baking soda to your water in order to boost its alkalinity. “Don’t over-consume alcohol or caffeine by sticking to one alcoholic or caffeinated drink per day or less,” he says. These 11 baby steps will help you ease into a plant-based diet.