Alkaline Diet Guidelines For Osteoporosis Prevention And Treatment
Alkaline diet guidelines emphasize fruit and vegetables and discourage excessive meat consumption. This is common sense, but is there more to it?
Both the National Osteoporosis Foundation (NOF) and the National Institute of Arthritis and Musculoskeletal and Skin Diseases (NIAMS) warn that excessive meat consumption can contribute to bone loss.
Acid/alkaline balance is one of the most puzzling concepts in the area of osteoporosis treatment.
The terms "acid, acidifying and alkalinizing" have been so misused that most of us are desperately seeking some alkaline diet guidelines. Some of this confusion is due to the fact that there are four distinct acid/alkaline factors in human health and nutrition.
Substances are rated as acidic or alkaline based on a pH scale in which water is neutral and holds a pH value of 7. Values less than 7.0 are acid and the stronger the acid, the lower the pH.
Common acids include acetic acid (vinegar), and hydrochloric acid-the digestive fluid secreted by the lining of your stomach. Acids taste sour and will turn a litmus paper red.
Alkaline substances (also called base substances) have a pH value greater than 7 up to 14. Common bases are sodium hydroxide (lye) and sodium bicarbonate (baking soda). They taste bitter and will turn litmus paper blue.
Both acidic and alkaline substances have important roles to play in the human body. The four factors of acid/alkaline balance related to osteoporosis are:
- The acid/alkaline quality of certain foods before they are eaten
- The acid/alkaline balance of the blood and body fluids
- The acid and alkaline chemistry of digestion
- The effect of foods after they are digested and metabolized- often referred to as acid/alkaline residue or ash.
A book that provides a clear overview of alkaline diet guidelines and how to balance different foods is Building Bone Vitality.
The acid/alkaline balance in our blood is not affected by the acid content of a food. In fact, the metabolism of most fruits results in an alkaline residue or ash... with the exception of cranberries and some varieties of plums.
Negative effects experienced from eating citrus fruits are most likely due to a food allergy; fermentation in the gastrointestinal tract due to maldigestion; or localized irritation from the citric acid in the fruit.
Fruits are sometimes classified as either acid, sub-acid, or sweet to help with the botanical description of the food. For example, oranges, grapefruit, lemons, limes, tangerines and kumquats are citrus fruits containing citric acid. Apples (sometimes classified as sub-acid) contain malic acid while cranberries contain benzoic acid.
Acid/alkaline balance refers to the relative pH of the blood, which must be kept within a narrow range around 7.4 (slightly alkaline). This vital function is accomplished largely by automatic buffer systems in the blood and the pH regulating action of the lungs and kidneys.
Acidosis Or Acidemia
The condition acidosis or acidemia refers to blood that is too acidic (less than 7.35) and is not caused by eating acidic foods such as lemons and oranges. It is usually the result of impaired metabolism caused by conditions such as diabetes, starvation (anorexia), kidney disease, or respiratory disorders that limit the release of CO2 from the lungs.
The blood buffer systems will adjust towards alkaline and the rate of breathing will increase to remove carbonic acid via the exhalation of carbon dioxide (CO2). Next, the kidneys increase the acidity of the urine and balance is quickly restored.
Alkalosis Or Alkalemia
Alkalosis or alkalemia is less common than acidosis but can result from hyperventilation (too rapid breathing); loss of stomach acid due to excessive vomiting; or over-use of antacids and/or ulcer medications. In this case, blood buffer systems adjust toward acid and breathing becomes more shallow to conserve CO2 and raise carbonic acid levels in the blood. Once again, the kidneys contribute to the balancing act by excreting more alkaline urine.
The Acid/Alkaline Chemistry Of Digestion
Contrary to popular advertising which encourages us to buy an array of antacid products, upset stomachs and heartburn are rarely caused by excess stomach acid.
They are more commonly caused by poor food selection, overeating, eating too fast or insufficient stomach acid, which causes maldigestion.
Research has shown that in the majority of cases the problem is too little stomach acid, especially in the elderly.
Antacids can help with the acidic by-products of food fermentation but may disguise the problem of poor eating habits. They may also cause malnutrition if used for prolonged periods because adequate stomach acid is needed to absorb most minerals, vitamin B12 and folic acid.
There are two stages to our digestion of food. During the first stage, we break our food down with stomach acid and an important enzyme called pepsin. Without sufficient hydrochloric acid, pepsin is inactive and maldigestion results.
The normal acid level of the stomach (between pH 1.5 and 2.5) is neutralized somewhat by the food we eat; but the stomach is able to re-acidify during the meal to complete its digestive function.
By the time our food is ready to pass into the small intestine, it is far less acidic – in the range of 3.5 to 5.0.
Digestion continues in the small intestine where 90% of all absorption takes place. Here the alkaline environment needed for absorption is created by the pancreas, which secretes the necessary quantity of bicarbonate.
Digestion is a complex and delicate process involving feedback mechanisms between stomach and pancreas to maintain optimal acid/alkaline levels.
Excessive use of medications that alter this balance may be harmful while following alkaline diet guidelines will help to maintain the balance.
Acid-Forming And Alkaline-Forming Foods
After food has been digested and absorbed it leaves a residue or ash that is either alkaline, acid or neutral depending on the mix of minerals found in the food.
Acid-forming foods are those that contain sulfur, phosphorus and iron which are found primarily in protein such as meat, fish, poultry, eggs, grains and most nuts. Soft drinks contain no protein, but lots of phosphate and thus are very acid-forming.
Alkaline-forming foods are those that contain potassium, calcium, magnesium and sodium... which are found primarily in fruits and vegetables.
But it is all a matter of balance. Milk is a high protein food, rich in sulfur and phosphorus (so you would expect it to be acid-forming) but it contains enough calcium (alkaline) so that it balances out to about neutral. Simple sugars and fats don't contain minerals of either category.
The North American Diet
Meat and soda consumption is decreasing in Canada but has increased in the U.S. far beyond recommended levels for osteoporosis prevention.
There is growing consensus that excessive acid-forming foods (meat and soft drinks) are a risk to bone health. North American consumption of these foods may be a partial cause of the high incidence of osteoporosis relative to other countries.
In “Strategies for Osteoporosis,” the National Osteoporosis Foundation warns that this excessive protein consumption can be damaging to bone health.
"Excessive protein and sodium intake can increase calcium loss through the kidneys. In fact, an individual's daily calcium requirement increases in direct proportion to the amount of protein and sodium in his/her diet."
The National Institute of Arthritis and Musculoskeletal and Skin Diseases (NIAMS) repeats this warning:
"Although a balanced diet aids calcium absorption, high levels of protein and sodium (salt) in the diet are thought to increase calcium excretion through the kidneys. Excessive amounts of these substances should be avoided, especially in those with low calcium intake."
Soft Drinks And Coffee
Medical research has identified a clear link between cola and osteoporosis but in the United States, soft drink consumption continues to increase.
A study conducted at the University of North Carolina at Chapel Hill, showed that energy intake from soft drinks in the United States increased 135 percent between about 1977 and 2001. Young adults ages 19 to 39 drank the most soft drinks, increasing their intake from 4.1 percent to 9.8 percent of total daily calorie consumption during that period.
Among coffee drinkers (i.e. not per capita) the average coffee consumption in the United States is 3.1 cups of coffee per day (National Coffee Association) and consumption is increasing.
According to Agriculture and Agri-Food Canada, per capita consumption of soft drinks in Canada has declined during the past decade but was still almost 110 liters per capita in 2006. (Canadian consumption of bottled water increased 132% during this period... to the great detriment of our environment and landfill.)
Soft drinks still hold the largest market share of all beverages that are sold (15%) although coffee consumption is increasing and was over 14% of the beverage market in 2006. Together these two acid producing drinks comprise almost 30% of beverages consumed by Canadians.
Research now suggests that people who are concerned about bone loss avoid cola drinks and drink decaffeinated coffee. if they can't live without their java. An even healthier choice would be to follow alkaline diet guidelines that protect bone health.
Meat consumption is declining in Canada but steadily increasing in the U.S. to an extraordinary 101 kg (223 pounds) per capita in 2007.
The Recommended Dietary Allowance (RDA) of protein for men is 56 grams/day and for women 46 grams/day from all food sources including meat, tofu, eggs, grains, legumes and dairy products.
Statistics Canada reports that Canadian consumption of red meat (including beef, pork, mutton and veal) and chicken has been slowly declining since 1999 to approximately 77 pounds (35 kg) per person in 2007 or 25 grams of protein a day. (This calculation is based on a conservative estimate of 25% protein for the combined meat groups. In Canada, red meat comprised 24.5 kg per person and poultry 10.6 kg per person.)
The USDA reported that Americans consumed 101 kg (223 pounds) of meat per person in 2007... or 72 grams of protein a day from meat alone... not including eggs, dairy, grain or legumes. As this includes every man, woman and child... adults are clearly consuming far more than the recommended level of animal-protein.
The current levels of meat and soda consumption in the United States are not supportive of osteoporosis prevention and are in direct opposition to alkaline diet guidelines.
The Research On Alkaline Diet Guidelines
A variety of research studies have warned us of the dangers of animal-proteins and the virtues of fruit and vegetable-based diets (alkaline diets) for osteoporosis prevention and treatment.
Cornell-China-Oxford Project (1996)
In 1996, the Cornell-China-Oxford Project on Nutrition, Health and Environment released its findings after studying the diets of 800 women in China.
The research concluded that increased levels of animal-based proteins, including protein from dairy products, "almost certainly contribute to a significant loss of bone calcium while vegetable-based diets clearly protect against bone loss."
Nutritional biochemist T. Colin Campbell and his colleagues concluded that reducing meat intake reduces the risk of losing bone density and that animal-protein, including that from dairy products, may leach more calcium from the bones than is ingested.
Nurses’ Health Study (1996)
The famous Nurses’ Health Study of 85,900 women over 12 years found that women who consumed five or more servings of red meat per week had a significantly increased risk of forearm fracture compared with women who ate red meat less than once per week.
This study is widely quoted by reputable institutions such as the Harvard School of Public Health. (Feskanich D, Willett WC, Stampfer MJ, Colditz GA. Protein consumption and bone fractures in women. Am J Epidemiol. 1996;143:472–9.)
Hip Fractures in Elderly Women (2000)
In 2000, a study on hip fracture in different countries found that incidence of fractures was directly related to high animal- protein intake. ("Worldwide incidence of hip fracture in elderly women: relation to consumption of animal and vegetable foods" PMID: 11034231 [PubMed - indexed for MEDLINE)
Fractures in Postmenopausal Women (2001)
In 2001, another study found that "a high ratio of dietary animal to vegetable-protein increases the rate of bone loss and the risk of fracture in postmenopausal women." (Sellmeyer DE, Stone KL, Sebastian A, Cummings SR. Study of Osteoporotic Fractures Research Group. Am J Clin Nutr. 2001;73:118–22.)
Calcium Supplements and Bone Loss (2009)
In 2009, a research program that provided 600 mg of calcium and 525 IU of vitamin D3 daily to 171 men and women found that those who also took sodium bicarbonate or potassium bicarbonate (which are alkaline substances) enjoyed better bone resorption and less calcium excretion.
This suggests that increased alkaline content in the diet may decrease bone loss in healthy older adults. (Dawson-Hughes B, et al "Treatment with potassium bicarbonate lowers calcium excretion and bone resorption in older men and women" J Clin Endocrinol Metab 2009.)
All of these studies suggest that a high intake of acid-forming foods (primarily meat, poultry, and eggs) threatens to accelerate the loss of alkaline minerals (calcium, magnesium, potassium) from the bones and contribute to osteoporosis.
We do not have to become vegetarians to prevent osteoporosis. But following alkaline diet guidelines by reducing our meat consumption and increasing vegetables and fruit in our diet is definitely indicated.
A general rule-of-thumb is to have a diet consisting of 20% acid-forming foods (grains and protein) and 80% alkaline-forming foods (fruits and vegetables).
A healthy goal would be to include at least two vegetable or fruit servings at every meal and to eat no more than two daily servings of carbs such as bread, cereal and pasta.
With mad cow disease, swine flu, avian flu, extensive use of antibiotics and hormones and unacceptable environmental damage from factory farms threatening us... eating more yummy leafy greens and fresh fruit is a great alternative.
To learn about supplements that reinforce a diet that follows alkaline diet guidelines... visit Osteoporosis Treatment Guidelines.
To purchase products related to acid/alkaline balance... visit our Osteoporosis Treatment Store.