Thursday, October 9, 2008

Acid-Base Balance

Numerous health authorities have proposed that the acid-base balance of a diet contributes to its effects on health, including Dr. Loren Cordain. Here's how it works. Depending largely on its mineral content, food yields net acid or base as it's metabolized. This is not the same as the acidity of a food as you eat it; for example, lemons are base-yielding. The pH of the body's tissues and blood is tightly regulated, so it must find ways to resist pH changes. One way it deals with excess acid and base is by excreting it. Acidifying food causes the urine and saliva to become more acidic, while alkalinizing food has the opposite effect.

Another mechanism some believe the body uses to neutralize acidity is by drawing calcium from the bones. The modern diet tends to be acid-yielding. Vegetables and fruit are base-yielding while meat, refined carbohydrate, dairy and most other foods are acid-yielding. Some authorities believe this leads to osteoporosis, cancer and a number of other health problems. This is one of the reasons we're told to eat immoderate quantities of vegetables.

I've always been skeptical of the acid-base balance theory of health. This mostly stems from the fact that many hunter-gatherer societies were essentially carnivorous, yet they didn't suffer from osteoporosis, tooth decay or any other signs of calcium deficiency. Also, if acid-yielding diets strip calcium from the bones, how did calcium get into the bones to begin with? The body clearly has mechanisms for creating and preserving bone density in the face of an acid-yielding diet, it's just a question of whether those mechanisms are working properly.

I came across a gem of an article today on acid-base balance by none other than Dr. Weston Price. As usual, he hits it out of the ballpark. There are two tables in the article that sum it up beautifully. In the first, he compares the occurrence of cavities in healthy non-industrial groups to genetically identical groups living on modern foods (wheat flour, sugar). As you know by now if you've been reading this blog, the modern groups have 5-100 times more cavities than their non-industrial counterparts, along with crooked teeth, feeble frames and a number of other problems.

In the second table, he lists the acid-base balance of the same non-industrial and modern groups. There is no real pattern. Some of the non-industrial groups ate a diet that was heavily acid-yielding (Inuit, he calls them Eskimo), while others were fairly balanced or even base-yielding (South sea islanders). The unhealthy modern versions, ironically, were fairly balanced between acid and base-yielding foods. This is not consistent with the idea that acid-base balance contributes to the diseases of civilization.

There was one consistent trend, however. The non-industrial diets tended to be higher in both acid and base-yielding foods than their modern counterparts. That means they were richer in minerals. Just as importantly if not more so, their diets were rich in fat-soluble "activators" of mineral absorption and metabolism that ensure the proper use of those minerals. These are the fat-soluble vitamins A, D and K2. Here's what Weston Price says:
It is not my belief that [tooth decay, dental/skeletal deformity, general poor health] is related to potential acidity or potential alkalinity of the food but to the mineral and activator content of the nutrition during the developmental periods, namely, prenatal, postnatal and childhood growth. It is important that the very foods that are potentially acid have as an important part of the source of that acidity the phosphoric acid content, and an effort to eliminate acidity often means seriously reducing the available phosphorus, an indispensable soft and hard tissue component.
In other words, the acid-base balance isn't what matters, it's getting enough minerals and the vitamins you need to make good use of them.

Why were the diets of healthy non-industrial people so rich in minerals? It's simple: they ate whole foods. "Empty calorie" foods such as sugar, vegetable oil and refined grains constitute more than half of the calories in the modern diet. Eliminating those "foods" and replacing them with whole foods instantly doubles your mineral intake. Properly preparing grains and legumes by soaking, sprouting or fermenting further increases their mineral availability. Add some grass-fed dairy, organ meats, shellfish and eggs for the vitamins and you're in business!

1 comment:

  1. Order a Sparkling White Smiles Custom Teeth Whitening System online and get BIG DISCOUNTS!
    * Up to 10 shades whiter in days!
    * Professional Results Are Guaranteed.
    * Better than your dentist.
    * Same as dentists use.

    ReplyDelete