The alkaline diet has been credited with numerous health benefits from preventing osteoporosis to curing cancer and everything in between. But is there scientific evidence to back it up?
You may recall from high school chemistry that the pH scale measures how acidic or alkaline an environment is. The scale runs from 0-14 with 7 being neutral. Scores from 0-7 are considered acidic and above 7 are alkaline.
Different parts of our bodies have a different pH. For example, our stomachs are extremely acidic (1.5 to 3.5 pH) in order to break down food and ward off harmful bacteria and microbes that we may consume. Our blood is slightly alkaline with an average reading of 7.4 and a range of 7.35-7.45.
The premise behind the theory is that our western diet is rich in acid-forming foods like meat, dairy, eggs, as well as, sugar and grains while it is low in alkaline-forming foods such as vegetables, fruits, lentils, beans and nuts. True enough. As our body aims to buffer the acidic-load of the food, it must draw on our alkaline reserves from our blood, tissues and, most importantly, our bones. It is believed that the continuous consumption of high-acid foods leads to the chronic robbing of precious minerals like calcium, magnesium and potassium thereby increasing our risk of osteoporosis among other conditions.
It has been shown that after consuming a diet rich in acid-forming foods the pH of our urine (not blood) does becomes more acidic. Further, urinary calcium levels were increased which has led to the assumption that this was as a result of the resorption (breakdown) of calcium from our bones to buffer the acid.
As much as diet may affect our urinary pH, our blood pH is tightly regulated through our kidneys and respiration. True metabolic acidosis, that is reduction in blood pH, only occurs in serious disease states or kidney failure. While a chronic poor diet may lead to some robbing of our minerals, particularly calcium, studies have shown that the pH of urine does not predict bone fractures or bone mineral density. Further, urinary losses of calcium are not a direct measure of osteoporosis. It is believed that the loss of calcium through the urine is compensated for by the increase in absorption which is trigged by the consumption of protein.
Protein is integral to both bone health and to prevent muscle loss (sarcopenia) that occurs with aging. Adequate intakes of calcium, protein and vitamin D are essential in order fully realize the benefit of each nutrient on bone and muscle.
Although the evidence is not there to justify eating less protein for bone health; nor is there scientific evidence that the alkaline diet prevents cancer. However, there are numerous health benefits in increasing the consumption of alkalizing vegetables, fruit, nuts and legumes in the diet.
Our western diets tend to be sodium rich and potassium poor. Sodium has been shown to exacerbate bone and muscle loss as well as increase the risk of high blood pressure and heart disease. A diet rich in alkalizing vegetables and fruits will provide plentiful potassium which will help increase the potassium to sodium ratio which has been shown to preserve muscle mass in older men and women as well as mitigate the risk of heart disease and stroke.
The research studies may not back up all the promises made by proponents of the alkaline diet; however, it cannot be denied that eating plentiful vegetables and fruits will reap numerous health benefits particularly for bone, muscle and heart health. Although diet is unlikely to change our meticulously regulated blood pH, one benefit of alkalizing urine is that it can reduce the risk of kidney stones.
Swiss chard is one of the richest sources of potassium. Lentils also provide potassium, protein and magnesium which are all vital for bone, muscle and heart health.
- 1 tablespoon olive oil
- 1 small onion, finely chopped (3/4 cup)
- 1 leek, whites finely chopped
- 1 tablespoon tomato paste
- 2 cloves garlic, minced
- Pinch of dried chillies
- 1 teaspoon dried oregano
- 1 cup lentils, rinsed
- 1 can (14.5 ounces) diced tomatoes with juice
- 2 bunches (about 1 1/2 pounds total) Swiss chard, stalks cut crosswise into 1-inch pieces, leaves torn into 2-inch pieces (keep stalks and leaves separate) (see photo)
- Coarse salt and ground pepper
- Fresh basil & drizzle of balsamic vinegar
- In a large saucepan with a lid, heat oil over medium-high. Add onion and leeks and sauté until translucent, about 3 minutes. Add tomato paste, oregano, thyme, garlic and chillies, salt and pepper. Stir to combine.
- Add lentils, 5 cups water and tomatoes with their juice; bring to a boil. Reduce heat to medium and simmer, partially covered, 20 minutes.
- Add chard stalks and cook until beginning to soften, about 5 minutes. Add chard leaves and cook until lentils and chard are tender, about 10 minutes.
- Garnish with fresh basil & drizzle of good quality balsamic vinegar.
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