Acid-Base Balance and Bone Health

Many people consider calcium as the only nutrient of importance for bone health, and whilst calcium is important, bone health is much more complex than simply one nutrient. There’s research to support other nutrients such as protein, and other micronutrients including potassium and vitamin K are also important for bone health.

For several years, there has been discussion about the influence foods can have on the acid-base balance (or pH level) of blood in the body and on health, especially bone health. The theory is that a diet consisting mostly of food metabolised to acids—such as protein, processed foods, and cereals—may increase the acidity of blood. There’s no evidence to support that you can change your body’s pH level through what you eat, as your body carefully maintains its pH balance through a process known as homeostasis. pH is tightly regulated at pH 7.4 (+/- 0.05), and almost every process in the body depends on this acid-base balance.

The pH can be kept constant at the expense of bone, as bone delivers alkaline calcium compounds to maintain the pH balance. Whilst this may seem like the perfect solution, an overstimulation of this process over time can lead to dissolution of the bone mineral content, and therefore reduced bone mass. This can lead to negative health effects in later life, such as osteoporosis.

Thus, the dietary advice would be to eat a diet high in alkaline-producing foods—such as fruits and vegetables, which are metabolised to alkaline bicarbonates—to maintain a healthy pH level and preserve bone mass and density.

To explore the ideas behind the alkaline-acid balance theory, let’s start by reviewing some science about bones. Bones are a dynamic type of dense connective tissue that is in a constant cycle of degradation and regeneration. There are many factors that stimulate the building and breakdown of bones including intakes of calcium and vitamin D, as well as the amount and type of physical activity.

Bone breakdown is also used to regulate the pH balance of blood. Bones are the storage banks for calcium and the degradation of bone results in the release of calcium, which has alkaline, or acid-neutralising, properties. In other words, when the pH of blood starts to decrease or become more acidic, calcium can assist in increasing the pH or making it more alkaline.

What the research says

A study published in the Journal of Clinical Endocrinology found that subjects who received an alkaline compound (bicarbonate) in an amount equivalent to nine servings of fruits and vegetables daily experienced lower levels of calcium lost in urine as well as loss of N-telopeptide, a marker for bone resorption (1). This finding supports the notion that following an alkaline diet decreases calcium loss through urine, thus preserving bone.

Interestingly enough, other studies have shown that “acidic” high-protein diets, especially those comprised of dairy protein, actually have beneficial effects on bone mineral density (2-4). One study published in the Journal of Clinical Endocrinology and Metabolism concluded that diets higher in dairy protein in premenopausal women favourably affected important bone health markers (4). Another study provided evidence that milk and dairy products, although considered acidic by some, neither produce acid upon metabolism nor cause a change in the acid-base balance of the body (5).

What’s the take-home message? While the science may have some conflicts, it is important to note that a diet high in fruits and vegetables is a safe and easy way to support bone health as well as other aspects of health. Additionally, diets higher in protein, especially dairy protein, have been shown to be beneficial for maintaining bone health.

Alkaline-acid balance with Isagenix

By including IsaLean Shake and a combination of fruits and vegetables into your diet, it is possible to follow an acid-base balanced diet as part of an Isagenix system. Fruits and vegetables are rich in potassium, and so can help to balance the excess acidity. Additionally, Isagenix products contain minerals like calcium and phosphorous, as well as vitamin D, which are all important for bone health.

It is also important to clarify that the content of a food doesn’t determine whether it is acid- or alkaline- producing in the body. For example, some foods (such as eggs) are alkaline in nature, yet acid-producing. Likewise, some acidic foods (such as citrus) are alkaline-producing. This is the reason why foods containing citric acid—such as Ionix® Supreme and Nourish for Life^TM—are actually considered alkaline-producing.

So whilst you can’t change the body’s pH level through what you eat, you can consume a healthy, balanced diet to support your body’s natural ability to maintain a neutral pH balance and in turn, maintain healthy bones.

 

References

1. Ceglia L, Harris SS, Abrams SA, Rasmussen HM, Dallal GE, Dawson-Hughes B. Potassium bicarbonate attenuates the urinary nitrogen excretion that accompanies an increase in dietary protein and may promote calcium absorption. J Clin Endocrinol Metab 2009;94:645-53.
2. Darling AL, Millward DJ, Torgerson DJ, Hewitt CE, Lanham-New SA. Dietary protein and bone health: a systematic review and meta-analysis. Am J Clin Nutr 2009;90:1674-92.
3. Fenton TR, Lyon AW, Eliasziw M, Tough SC, Hanley DA. Phosphate decreases urine calcium and increases calcium balance: a meta-analysis of the osteoporosis acid-ash diet hypothesis. Nutr J 2009;8:41.
4. Josse AR, Atkinson SA, Tarnopolsky MA, Phillips SM. Diets higher in dairy foods and dietary protein support bone health during diet- and exercise-induced weight loss in overweight and obese premenopausal women. J Clin Endocrinol Metab 2012;97:251-60.
5. Fenton TR, Lyon AW. Milk and acid-base balance: proposed hypothesis versus scientific evidence. J Am Coll Nutr 2011;30:471S-5S.