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Acid-Alkaline Foods Made Simple
Remember, it’s not whether the food itself is acidic or alkaline, but how the food’s content of potassium, sodium, bicarbonate, and chloride shift the body’s pH. The key is to eat sufficient alkaline-forming foods to offset acid-producing foods. Fresh fruits and vegetables are the alkaline-forming foods, so eat plenty of them. Here’s a quick and simple guide.
Alkaline-yielding foods: All fresh fruits and vegetables
Acid-yielding foods: Dairy (milk, cheese, yogurt); eggs; fish; fowl; grains (including breads, cereals, bagels); legumes; meat; nuts; rice; sugars
Maintaining a normal body pH, or acid-alkaline balance, is one of the most important aspects of health. It’s also one of the most misunderstood-and most ignored. In fact, many dietitians scoff at the role of pH, partly because the subject has had, at times, a checkered past. But physicians know enough to take a strongly acidic pH very seriously. The reason is that “acidosis” can be dangerous, such as in cases of renal acidosis, a sign of kidney failure.
Acute forms of acidosis are relatively rare, but a far more common problem may be chronic “low-grade metabolic acidosis,” according to Anthony Sebastian, MD, of the University of California, San Francisco. Rather than causing immediate symptoms, health problems are often attributed to other causes, such as aging or not consuming enough calcium.
What does any of this have to do with nutrition?
Your eating habits influence your body’s pH in a big way. Over the years, a few self-styled experts have misinterpreted research on pH or confused acidic foods with an acidic body pH. For example, tomatoes and oranges are acidic, but they actually promote an alkaline pH.
How acid-yielding foods cause problems
If you’ve forgotten your high school chemistry, pH stands for “potential of hydrogen”-the activity of hydrogen atoms influences acidity and alkalinity. A pH below 7 is acidic, and a pH above 7 is alkaline. Water is neutral at 7, your car’s battery acid has a pH of 1, and bleach has a pH of 12.5.
The ideal body pH is 7.0 or slightly alkaline, such as 7.1. Low-grade metabolic acidosis develops when someone eats too many foods that promote an acidic pH. These acid-yielding foods include whole and refined grains, meats, dairy products, eggs, and seafood. That doesn’t mean these foods are unhealthful-just that they should be part of an overall pH-balanced diet.
When acid-yielding foods lower the body’s pH, the kidneys respond by coordinating metabolic activities to buffer that acidity. In turn, bones release calcium and magnesium to promote an alkaline pH, and muscles are broken down to produce ammonia, which is strongly alkaline.
On a day-to-day basis, you won’t notice that the body is breaking down bone and muscle. It takes decades for the consequences to become apparent in the form of osteoporosis and the loss of muscle, which contribute to the frailty associated with aging.
The good news is that you can eat to maintain a normal pH at any age. All fresh fruits and vegetables have an alkaline-yielding benefit, helping to shift the body toward a neutral pH. You just have to eat enough of them-about 35 percent of all your calories, according to Loren Cordain, PhD, of Colorado State University.
What causes an acidic or alkaline pH?
According to Sebastian and Cordain, several dietary factors determine the body’s pH. Diets high in sodium and chloride have an acid-yielding effect, whereas those high in potassium and bicarbonate have an alkaline-yielding effect.
Potassium vs. Sodium. Fruits and vegetables are rich in potassium compounds, which function as natural buffers. According to Cordain, humans evolved eating a 10:1 ratio of potassium to sodium, which he regards as our norm. Because of heavily salted processed and fast foods, combined with a low intake of fruits and vegetables, the ratio is now 3:1 in favor of sodium. That reversal, he says, shifts us toward an acidic pH.
Sodium, found in salt, is added to the vast majority of processed foods-that is, foods sold in boxes, bottles, jars, and cans, as well as those served in restaurants. Greatly reducing your consumption of salt-containing foods is an important step toward reducing an acidic pH.
Bicarbonate vs. Chloride. Because most Americans eat few fruits and vegetables, they don’t consume much naturally occurring bicarbonate, such as potassium bicarbonate. However, the modern diet is rich in chloride-again found in salt and most processed and packaged foods. Bicarbonate supports a healthy cardiovascular system, whereas chloride constricts blood vessels and reduces circulation, increasing the risk of heart disease, stroke, and dementia.
The problems associated with sodium and chloride can be exacerbated by either high-protein or high-grain diets, including cereals, breads, and pastas. The metabolism of protein releases sulfuric acid, which further promotes the breakdown of bone and muscle. Grains are the most widely consumed plant food in the United States, but they are acid yielding. The key to a neutral pH, again, is to balance protein and grains with large amounts of fresh fruits and vegetables.
Can supplements help with pH?
Some supplements, such as potassium citrate and bicarbonate, can also contribute to a normal or slightly alkaline pH. However, potassium supplements come with a caution: do not start taking large amounts of potassium. Stick with the 99 milligrams found in many supplements, unless a nutritionally oriented physician suggests that you take more. The reason is that sudden, large amounts of potassium can affect the body’s electrolyte balance (with sodium and other minerals) and lead to irregular heartbeats. This caution applies doubly if you take any kind of heart medication. High-dose potassium bicarbonate is sold as a prescription, not a nutritional supplement.
Again, potassium-rich foods are a safe alternative. A handful of raisins, two dates, or a small banana each provide more than 300 milligrams of potassium. Eleven ounces of coconut water provides more than 600 milligrams of potassium.
If you take mineral supplements, opt for the citrate form, such as calcium citrate and magnesium citrate. The body can convert citrate to bicarbonate, which promotes an alkaline pH. In one study, potassium citrate supplements protected against calcium losses, even when people ate a high-salt diet. Aspartates, fumarates, and succinate mineral compounds also have an alkalizing effect.
Third, remember that supplements are just that-supplements. No amount of supplements will offset poor eating habits. So combine your supplements with a diet that includes a lot of fruits and vegetables.
Measuring your pH
It’s easy to measure your pH. First, order a roll of pH test strips, which cost $10 to $16. You can find many difference sources at health food stores or by typing “pH test strips” into Google. Cut off a 3-inch strip of the paper and urinate over it. The paper will change color within seconds, and you can compare it to a chart that should come with the test strips. The normal pH range of urine is 6.5 to 7.5, though 7.0 or higher is best. Make a note of your pH over the course of a week, then calculate the average over this time.
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