Have you heard of the alkaline diet?
The aim is to avoid foods that leave an “acidic ash” (based on the theory that certain foods like meat, dairy, eggs, grains and processed foods may cause the body to produce more acid). Conversely, other foods — including fruits, vegetables and legumes — contribute to the production of alkaline by-products.
Supporters of an alkaline diet claim that it can optimize health and help with weight loss by reducing production of acid, though the results will likely be comparable to other diet plans. But this diet does emphasize healthy foods that may benefit your bone and kidney health.
Alkaline diet basics
Here’s a quick reminder: the pH (“power of hydrogen”) scale is a measure of the acidity or alkalinity of substances. The scale runs from 0 to 14, with 7 considered neutral. Acidic is below 7; alkaline is above 7.
The body has tightly controlled systems for maintaining a narrow window for pH levels. The kidneys maintain blood pH by absorbing or excreting compounds. Because of this buffering system, the acid load of your diet won’t significantly change your blood pH — but, over time, a high-acid diet may have health consequences.
The alkaline diet and your health
Alkaline diet and your bones: Bone density is the amount of bone mineral in your bones (and is a measure of bone strength). Any reduction in bone density raises your risk for osteoporosis — fragile bones that are susceptible to fractures. Some research has suggested that high-acid diets cause calcium to be leeched from the bones, likely accompanying a reduction in bone density.
Alkaline diet and your kidneys: High-acid diets may also contribute to kidney stone formation as well as to a greater risk for kidney failure. In a 2015 study (Journal of the American Society of Nephrology) involving 1,486 people with chronic kidney disease, those who consumed a high-acid diet were three times more likely to develop kidney failure than those with low-acid diets.
An alkaline diet can be healthy overall
The body’s mechanism for maintaining its pH balance is highly regulated, and it also varies throughout the body For example, the pH of the stomach is acidic whereas blood is more alkaline. Keep in mind that certain foods will affect pH differently if combined with certain other foods, meaning that a food’s individual pH scale might not be particularly relevant.
That said, the dietary pattern promoted in the alkaline diet — rich in vegetables, fruits and legumes, and lower in animal proteins and sodium-laden processed foods — happens to be one most health experts recommend for optimal health, as long as you don’t take it too far. As always, talk with your doctor or dietitian before beginning a new dietary regimen to decide if it is right for you.
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