The Alkaline Diet has been all the rage lately, with celebrities like Kate Hudson and Elle Macpherson touting the benefits of high-alkaline diets versus acidic ones. Claims have also been made that a such a regimen can be helpful for weight loss, cancer, osteoporosis, and other diseases and ailments, but many people are confused by the concept or explain it inaccurately. Today’s post is dedicated to analyzing if there are any real benefits to this type of diet—and what it is in the first place.
First Thing’s First… What is The Alkaline Diet (And What Do We Mean by “Acid” and “Alkaline”?)
If you think back to your high school chemistry days, you might remember the pH scale, which essentially measures how acidic or alkaline/basic a substance is. The pH scale ranges from 0 - 14. Anything with a pH below 7 becomes increasingly acidic, anything with a pH above 7 becomes increasingly alkaline (or basic), and 7 is neutral.
Different foods leave different byproducts behind after they’re metabolized called their “ash.” Some substances produce acidic ashes while others make alkaline ashes. Proteins produces acidic ashes like phosphates, sulfates, and uric acid, while foods that contain minerals like calcium, magnesium, and potassium produce an alkaline ash.
Because our blood comes into contact with almost every cell in our body, it’s critical that its pH level falls somewhere between the narrow window of 7.35 and 7.45. If your blood pH were to dip below 7.35, the hemoglobin in your blood wouldn’t be able to carry as much oxygen to your cells and you could die. Thankfully, however, our kidneys, lungs, and chemical buffers in our bodily fluids help to excrete excess acids or bases so that our body is never too acidic or alkaline. And if you were to die from having “acidic blood,” it would be due to a medical condition, not because you ate a burger.
The Alkaline Diet say that even slight changes to our pH toward the more acidic side of 7.35 are harmful, stating that an excess of acid-forming foods leave your body with no choice but to leech minerals like calcium from your bones or teeth to achieve balance.
“Acidic” versus “Alkaline” Foods
According to an article in the American Journal of Clinical Nutrition, fish, meat, poultry, eggs, shellfish, cheese, milk, cereal grains, and salt produce more acid whereas fresh fruit, vegetables, tubers, roots, and nuts are more alkaline-producing. Legumes are neutral. You’ll note that the higher the protein content of a food, the more acidic it is (generally speaking).
Something called the Potential Renal Acid Load (PRAL) score has also been created precisely to help people figure out just how acid- or alkaline-forming different foods are.(Check out this website for a detailed list of each food’s score.)
So, Is There Any Merit to the Acid-Alkaline Diet?
Kinda. According to a study in the American Journal of Clinical Nutrition, the typical Western diet leaves behind a high amount of acidic ash, which can result in chronic, low-grade metabolic acidosis that worsens with age—a condition where your kidneys aren’t removing enough acid from the body. And interestingly, long before the Industrial Era—where people ate a lot more fruits, vegetables, and healthy meats—diets were mainly alkaline. Known benefits of this include preventing and treating: osteoporosis, age-related muscle wasting, calcium kidney stones, hypertension, and exercise-infused asthma.
A study in the Journal of Environmental and Public Health also stated that increased fruits and vegetables in an alkaline diet would improve the potassium to sodium ratio and may benefit bone health and reduce muscle wasting, which, in turn, would improve outcomes for cardiovascular health, memory, and cognition. In this case though, it sounds like the benefits are associated with the vegetable and fruits themselves, not with their effect on your body’s pH levels.
In terms of people who claim it helps them lose weight, I’m not surprised. Considering acid-forming foods are meat, dairy, some nuts, and a lot of grains, all you’re really left with are vegetables, fruits, some legumes, and soy products, which typically aren’t associated with weight gain.
Of course, not everyone always agrees on nutritional matters. In their analysis of 55 different studies, the Nutrition Journal confirmed that “there is no evidence that an alkaline diet is protective of bone health.” Additionally, they confirmed that randomized studies did not provide evidence for an adverse role of milk and grain foods on osteoporosis.
The Bottom Line