Food For Your Bones

By Susan E. Brown, PHD, CNS, Natural Solutions

Despite our society’s seemingly obsessive focus on calcium intake, studies repeatedly show that the cultures with the highest dairy consumption, and thus the highest calcium intake, exhibit the greatest incidence of osteoporotic fracture. This observation has led to the identification of a mysterious “international calcium paradox.” How is it that in the U.S. 1,000 to 1,500 mgs or more of calcium daily are considered necessary for maintaining bone health, while many other populations maintain strong bones with a calcium intake of 400 mg or less?

It turns out that calcium intake is only part of the equation, and that an appropriate dietary reference intake (DRI) for a given population depends on coexisting dietary, lifestyle and environmental factors. These include the balance between the total intake of other nutrients and the consumption of potentially bone-damaging substances such as excess salt, protein, alcohol, tobacco, fat, processed foods and sugar. The use of certain bone-depleting medications, the lack of sunlight, the presence of environmental toxins and even stress have deleterious effects on bones.

The most overlooked, however, and perhaps the most important of all the culturally created bone-depleting factors is known as “diet-induced chronic, low-grade metabolic acidosis.” In other words, our nutrient-deficient and imbalanced diet produces an excess of acids in the body that damages and, in effect, “eats away” our bones.

This occurs because our biological systems are genetically hard-wired to maintain the body’s chemical balance–its slightly alkaline pH level–at all costs to ensure minute-to-minute survival. And when we consume a diet high in acid-forming substances and fail to supply the body with sufficient base, or acid-neutralizing nutrients such as potassium, it goes in search of the next available sources. It looks first in the bloodstream, then to the cells and tissues, and then to its rainy-day alkali reserves in the bones.

Bones and the Defense of the Acid-Alkaline Balance
You likely know that bone stores the vast majority of the body’s three-plus pounds of calcium. When blood calcium declines to dangerous levels, the body draws calcium out of the bones to replenish it. If the body withdraws more calcium from bone than it deposits, over time it depletes the bones’ reserves, and the resultant loss of bone mass leads to osteoporosis. But bone also holds most of the body’s essential alkali reserves. These mineral compounds take the form of alkalizing calcium salts and are capable of buffering, or detoxifying, acids. They stand by in the blood, body fluids, cells, tissue and bone to buffer any excess acids produced by the body’s biochemical workings–neutralizing them through spontaneous biochemical reactions that keep the acids from accumulating.

A diet that balances base- and acid-forming foods maintains the body’s systemic pH balance. If acid-forming foods predominate, however, as is the case in the typical Western diet, the first-line alkali reserves in the blood and cells are soon exhausted and the body starts using minerals stored in the bones.

The body’s goal here is basic survival, and if it becomes even slightly acidic, it willingly sacrifices the structural integrity (strength) of the bones in order to recover the systemic acid-base balance. Simply put, the body places its short-term need to survive above a long-term need for strong bones.

Diet and the Acid-Base Balance
Diet is clearly a major influence on the body’s acid-base balance. Certain foods, such as proteins, grains, beans, coffee, white sugar and many processed foods, generate free acid as they are metabolized. Other foods contain mineral compounds such as potassium citrate and magnesium salts that generate bicarbonate, the body’s main compound for detoxifying and removing metabolic acids from the body.

A diet balanced in base-forming and acid-forming foods creates little or no acid buildup and no threat to bone alkali reserves. A base-forming diet is familiar to humans; in fact, scientists calculate that during the vast majority of human evolution our diet was, indeed, overall base forming. The contemporary diet of industrialized countries, however, is uniformly acid forming or “acidogenic.” Returning to an alkali-rich, base-forming diet provides the cornerstone of a new diet for healthy bones.

Back to Basics
Our prehistoric past provides key insights for a modern healthy bones diet. Our ancestral diet was nutrient dense–rich in vitamins, minerals, phyto-compounds, omega-3 fatty acids and protein. This balanced diet provided sufficient alkaline-forming foods to buffer the acids produced as a by-product of eating lots of animal flesh. Ancestral bones, it appears, were only infrequently sacrificed in order to maintain critical systemic pH balance.

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