Rather than obsessing over an acid-alkaline food chart, simply eat a diet rich in plant foods, along with adequate protein, writes nutritionist Carrie Dennett.

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On Nutrition

Should you worry about the acidity of your diet?

Is the ticket to good health and disease prevention an “alkaline” diet? Proponents of this type of diet claim that so-called “acid-forming” foods can contribute to everything from osteoporosis to heart disease to cancer.

Your body maintains the pH of your blood within a very narrow range (7.35-7.45 on a scale of 1-14, with a pH of less than 7 being acidic). This is crucial, because a large fluctuation in pH would make your body stop working. Your lungs and kidneys work together to maintain tight pH control, counteracting the acid load you get from food and from the waste products of normal metabolic processes.

An acid-forming diet does not literally make your body full of acid, and acidic foods like lemons are not necessarily acid forming. Rather, foods are classified as acidic or alkaline depending on the minerals they release into your urine.

Potentially acidic foods include many protein foods (meat, fish, shellfish, poultry, eggs, cheese, peanuts), grains, certain fats (bacon, nuts and seeds), coffee and alcohol. Potentially alkaline foods tend to be rich in potassium and magnesium. They include vegetables, fruit, lentils, spices and herbs, molasses, brown sugar and cocoa powder. Neutral foods include butter, oils, milk, corn, white sugar, honey, water and tea.

Advocates of alkaline diets say that the modern diet — typically high in animal protein and salt and low in fruits and vegetables — produces excess acid, contributing to modern diseases. It’s true that if your dietary acid load is very high, your body’s regulatory mechanisms can’t maintain balance. However, even the typical less-than-ideal American diet doesn’t produce that high of an acid load.

The average person can maintain normal acid-base balance through a wide range of acid intake from foods. Within minutes of an imbalance, your body compensates by adjusting how fast you breathe (and how much carbon dioxide you exhale). Your kidneys react more slowly, adjusting how much bicarbonate they release (bicarbonate is an electrolyte that helps buffer excess acid).

The theory is that an acid-forming diet leads to disease because it forces your body to use key minerals — like calcium, magnesium and potassium — as acid buffers, instead of using them for bone health, heart health and prevention of other diseases. Scientific research does not support this idea.

Research from several decades ago indicating that cancer cells thrive in an acidic environment has also been overridden by more recent discoveries that cancer cells likely create that acidic environment themselves.

Much of the research on the acid-alkaline balance of the diet is in relation to bone health, specifically osteoporosis. However, there is no solid evidence that dietary acid load causes osteoporosis or that an alkaline diet protects bones. In fact, recent research suggests that we need adequate protein to maintain healthy bones.

Many foods that have been classified as acid forming have not been specifically evaluated for their effects on bone health or other diseases. Instead, researchers have measured the pH of urine, which is not a reliable indicator of blood pH, let alone disease risk.

The bottom line is that while a diet rich in vegetables and fruits has been shown to have health benefits, it may be for reasons that have nothing to do with the alkaline nature if these foods. Rather than obsessing over an acid-alkaline food chart, simply eat a diet rich in plant foods, along with adequate protein.

Oh, and drink plenty of water (special alkaline water not necessary), as dehydration may be acid forming, too.