Fruits and Vegetables are Good for Bones

A Plant-Based Diet has Multiple Health Benefits

Mar 21, 2009

Calcium and vitamin D have always been credited for strong bones. A new study suggests a diet rich in fruits and vegetables offers similar advantages.

Several studies have reported that diets high in protein and cereal grains produce an excess of acids in the body disrupting its acid-base balance. When this occurs, the body restores equilibrium by breaking down bone and using the minerals as buffering agents. Unfortunately, this compromises bone architecture and strength which can lead to increased risk of bone fractures.

Dr. Dawson-Hughes and her colleagues showed that a high fruit and vegetable diet supplemented with an alkali pill strengthens bones. Their study was published in the 2008 issue of The Journal of Clinical Endocrinology and Metabolism.

After the domestication of animals and introduction of agriculture, humans began consuming a diet that generates higher levels of metabolic acids. This diet contain high protein and fat, cereal grains, and less"wild" fruits and vegetables - akin to the modern Western diet.

The Importance of Acid-Base Balance in the Human Body

The human body tightly regulates its level of acidity or alkalinity. When blood pH level drops below 7.35, it will initiate several mechanisms to restore balance. Human blood is slightly alkaline with a pH range of 7.35 - 7.45. When acidosis occurs, osteoclasts initiate bone resorption - a process where osteoclasts break down bone and release the minerals resulting in a transfer of calcium from the bone fluid to the blood. Acidosis denotes high levels of acid in the body.

The body also stores excess acid in connective tissues; causes the lungs to expel more carbon dioxide, and the kidneys to excrete more uric, ketones, and other acids. The results of these strategies are systemic inflammation and degeneration, and decreased lung and kidney functions.

Acids are normal by-products of living (metabolism), but acidemia - a condition in which the blood contains too much acid - can occur due to certain diseases, inflammation, poison ingestion such as methanol, ammonium chloride etc., high meat and cereal grain intake and low fruit and vegetable consumption. Age is also a factor in acidosis. As people age, they are less able to excrete metabolic acids due to the normal decline in kidney function.

How Fruits and Vegetables Inhibit Bone Loss

Fruits and vegetables are rich sources of bicarbonates - alkaline compounds that neutralize acidity. A consumption of 3-7 servings of fruits and vegetables everyday reduces urinary calcium losses by about 50 mg per day. Fruits and vegetables also contain vitamins and minerals such as vitamin D, calcium, phosphorus, and magnesium that are known to modulate skeletal health.

Health Canada recommends that Canadians consume a wide variety of fruits and vegetables everyday.

Dawson-Hughes B et al. " Treatment of Potassium Bicarbonate Lowers Calcium Excretion and Bone Resorption in Older Men and Women" The Journal of Clinical Endocrinology and Metabolism

Vortmann J & Renner T "Dietary, Metabolic, Physiologic and Disease-Related Aspects of Acid-Base Balance" Foreword to the Contribution: The Second International Acid-Base Symposium The Journal of Nutrition February 2008;138:413S -414S

Renner, Thomas "Influence of Diet on Acid-Base Balance" Seminars in Dialysis July/August 2000;13(4):221-226

The copyright of the article Fruits and Vegetables are Good for Bones in Nutrition is owned by Alicia Richardson. Permission to republish Fruits and Vegetables are Good for Bones in print or online must be granted by the author in writing.