Alkaline diet

Alkaline diet (also known as the alkaline ash diet, alkaline acid diet, acid ash diet, and the acid alkaline diet) describes a group of loosely related diets based on the belief that certain foods can affect the acidity (pH) of bodily fluids, including the urine or blood, and can therefore be used to treat or prevent disease. Due to the lack of credible evidence supporting the benefits of this diet, it is not recommended by dietitians or other health professionals.

Human blood is regulated at pH 7.35 to 7.45. Levels above 7.45 are referred to as alkalosis and levels below 7.35 as acidosis. Both are potentially serious, and the body has acid–base homeostasis mechanisms that generally ensure this does not happen. The idea that this diet can materially affect blood pH, or treat a range of diseases, is incorrect.

Diets avoiding meat, poultry, cheese, and grains can be used in order to make the urine more alkaline (higher pH). However, difficulties in effectively predicting the effects of this diet have led to medications, rather than diet modification, as the preferred method of changing urine pH. The "acid-ash" hypothesis was once considered a risk factor for osteoporosis, though the current weight of scientific evidence does not support this hypothesis. It is, therefore, widely dismissed as pseudoscience.

The term "alkaline diet" has also been used by alternative medicine practitioners, with the proposal that such diets treat or prevent cancer, heart disease, and low energy levels as well as other illnesses. These claims are not supported by evidence and make incorrect assumptions about how alkaline diets function that are contrary to human physiology.

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