What is Alkaline Diet

Much has been written in the lay literature as well as many online sites expounding on the benefits of the alkaline diet. This post is an attempt to balance the evidence that is found in the scientific literature.

Life on earth depends on appropriate pH levels in and around living organisms and cells. Human life requires a tightly controlled pH level in the serum of about 7.4 (a slightly alkaline range of 7.35 to 7.45) to survive ¹. The ‘acidity’ of human blood is highly stable (pH = 7.35–7.45) in healthy individuals and cancer patients ². The pH is a number that shows how acidic or alkaline a substance is. A pH of less than 7 is acidic, and greater than 7 is alkaline. The pH of blood is about 7.4. Acidosis also called acidemia is a condition in which there is a shift in the acid-base balance of your body to have more acid than normal, often causing the pH of your blood and body tissues to fall below pH 7.35 (the healthy normal range of pH is between 7.35-7.45, with the average at 7.40). Acidosis occurs when acid builds up or when bicarbonate [HCO3^–] (a base) is lost.

Acidosis can be due to increased acid or decreased base:

• Increased acid production within the body
• Consumption of substances that are metabolized to acids
• Decreased acid excretion
• Increased excretion of base

Acidosis may also be caused by decreased carbon dioxide (CO₂) elimination in respiratory disorders such as emphysema, by metabolic problems such as kidney disease and diabetes, or as the result of ingesting poisons (ethlylene glycol, methanol) or overdosing on certain medication (salicylates); it can also be caused by losing bicarbonate (HCO₃^–), as in diarrhea.

Alkaline diet refers to the idea that as foods are digested and metabolized, they create a more alkaline environment in the body ³, ⁴. For example, animal protein is a major source of sulphur-containing amino acids that create a higher acid load in the body. The amount of acids released is related to the type of amino acids they contain. In fact, amino acids can be divided into neutral (alanine, phenylalanine, glycine, isoleucine, leucine, methionine, proline, tryptophan, valine, asparagine, glutamine, serine, threonine, cysteine, and tyrosine), acidic (aspartate and glutamate), and alkaline (arginine, histidine, and lysine). Specifically, lysine, arginine, and histidine form hydrochloric acid, while cysteine and methionine are converted to sulfuric acid ⁵. Moreover, foods containing phosphorus, both of natural origin or from food additives, further increase the acid load introduced with the diet ⁶. On the other hand, vegetables and fruits are major sources of certain minerals, especially potassium, after being metabolized, produce alkali species that are able to neutralize acids ⁷.

The proponents of alkaline diet believe that an acidic environment promotes ill health whereas an alkaline environment is beneficial and promotes good health, based on the “acid–ash” hypothesis developed over 100 years ago ⁸, ⁹. The acid–ash hypothesis suggests that to achieve a more alkaline load, you must consume more fruit and vegetables with only a moderate intake of protein. The diet also calls for avoiding added sugars. They claimed that the food you eat can affect your body’s pH and that as your blood that is naturally alkaline (pH 7.4) is being upset by eating acid foods. By trying to change your blood pH to be more alkaline through eating mostly alkaline foods, followers of alkaline diet believe that they can cure disease, including cancer. Proponents of the Alkaline Diet say that when you load up on excess amounts of protein, sugar, caffeine and other highly processed foods, your pH levels are thrown off track, your bodies become more acidic, and that can lead to weight gain and disease. The remedy, they say? Eat fresh vegetables, fresh fruit and other “alkaline-promoting foods” such as soy products, legumes, and certain nuts and grains. “Acid-promoting foods”, which include meat, fish, poultry, dairy products, processed foods, white sugar, white flour, and caffeine, are discouraged. Because alkaline promoting foods has a higher pH level than does acid promoting foods, proponents of the alkaline diet say that it can neutralize acid in your bloodstream, boost your metabolism and help your body absorb nutrients more effectively. Some even say that alkaline promoting foods can help prevent disease and slow the aging process. Researchers haven’t verified these claims. Despite this, many of those following an alkaline diet insist on testing the pH of their urine multiple times per day to make sure that their bodies aren’t too acidic. Moreover, marketers of alkaline diet imply that the diet changes will raise your blood pH, but a well-conducted randomized trial of alkaline diet changes altered only your blood pH by 0.014 units, while the urine pH increased by 1.02 units ¹⁰. Another study reported that high fruit and vegetable consumption and low meat intake could significantly alkalinize the urine pH in healthy men and women of ages up to 79 years ¹¹. While diet and other metabolic processes can affect the pH level of your urine, what you eat does not determine your blood’s pH level. And the pH of your urine has no effect on weight loss and no correlation with the risk of cancer or inflammation-related medical conditions.

The alkaline diet proponent suggests that eating an alkaline diet can create a hostile alkaline environment and therefore kill cancer. Interest in an alkaline diet mostly stems from laboratory studies suggesting that cancerous tumor cells have an acidic environment  (pH ~6.5) surrounding them, which promotes the invasiveness of the cancer cells (e.g., by activating proteolytic enzymes and digesting their surroundings) whilst inhibiting the growth of the normal host cells ¹², ¹³, ¹⁴. However, neither cancer cells nor healthy cells can survive in an alkaline environment. Scientists are investigating whether this acidic environment promotes cancer development or enhances metastasis ¹⁵.

Your blood pH (7.4) is tightly regulated by your kidneys and respiratory system. Any excess acid is excreted in the urine. Your blood pH is not altered by your dietary intake. The only situation in which blood pH is altered is during metabolic acidosis, when an individual is critically ill. Furthermore, there is no scientific literature establishing the benefit of an alkaline diet for the prevention of cancer at this time ¹⁶. A 2016 systematic review of studies on alkaline diet and cancer found that an alkaline diet could change the pH of urine to be more alkaline, but not that of the whole body ¹⁶. The body regulates the pH of blood through several internal processes. Food does not affect it. This systematic review of the literature revealed a lack of evidence for or against diet acid load and/or alkaline water for the initiation or treatment of cancer ¹⁶. Promotion of alkaline diet and alkaline water to the public for cancer prevention or treatment is not justified ¹⁶. Additionally, a review of the body of evidence regarding the acid–ash or alkaline hypothesis for bone health found that the hypothesis is not supported and there is no evidence that altering the diet acid load improves bone health ¹⁷.

Since the 2016 review ¹⁶, a 2019 observational study ¹⁸ found that diets categorized as more acid-producing were associated with increased risk, and alkaline diets were associated with decreased risk, of estrogen receptor-negative (ER-) and triple-negative breast cancers. Another observational study ¹⁹ found that scores suggesting a more acidic diet were linked with increased markers of inflammation and poorer outcomes among some early-stage breast cancer survivors. Diet scores associated with blood and urine pH are derived from calculations based on total animal protein consumption and levels of one or a few minerals.

Current scientific evidence points to the benefits of alkaline diet for people with chronic kidney disease ²⁰, ²¹, ²², ⁵. Many studies have shown that a diet high in acid load is associated with an increased incidence of chronic kidney disease (CKD), CKD progression ²³, ²⁴, ²⁵ and diabetes ²⁶. Chronic kidney disease (CKD) means that your kidneys are damaged and can’t filter blood as they should. This damage can cause toxin and wastes to build up in your body ²⁷. Chronic kidney disease (CKD) can also cause other problems that can harm your health ⁵. Chronic kidney disease (CKD) common complications include hyperkalemia, metabolic acidosis, calcium-phosphorus metabolism impairment, water and sodium metabolism alterations, changes in the composition of the gut microbiota, oxidative stress, hyperhomocysteinemia, chronic low-grade inflammation, and normocytic normochromic anemia ²⁸, ²⁹, ³⁰, ³¹, ³². Diabetes and high blood pressure are the most common causes of chronic kidney disease (CKD). If left unchecked, chronic kidney disease (CKD) can evolve into end-stage renal disease (ESRD). At this stage, the kidneys are no longer able to remove enough wastes and excess fluids from the body. At this point, you would need dialysis or a kidney transplant.

In summary, eating a diet with plenty of fruits and vegetables – which is what some people mean when referring to an alkaline diet –  gives many health benefits and can help maintain a healthy weight. A study from more than 100,000 people starting in the mid-1980s until 2014 found that eating an average of five servings of fruits and vegetables a day is linked to a reduced risk of death from heart and respiratory diseases. Eating more fruit is also associated with a lower risk of cancer. Most types of fruits and vegetables led to these results, except fruit juices and starchy vegetables such as peas, corn, and potatoes. Try to eat about 3 to 5 servings every day. Fruit is also a good source of fiber, vitamins, and minerals. You should try to eat about 2 to 3 servings of fruit each day. However, the average American adult only eats about one serving of fruit and 1.5 servings of vegetables a day.

The Role of pH in Various Cells, Organs, and Membranes

The pH in our body may vary considerably from one area to another with the highest acidity in the stomach (pH of 1.35 to 3.5) to aid in digestion and protect against opportunistic microbial organisms. But even in the stomach, the layer just outside the epithelium is quite basic to prevent mucosal injury.

The skin is quite acidic (pH 4–6.5) to provide an acid mantle as a protective barrier to the environment against microbial overgrowth. There is a gradient from the outer horny layer (pH 4) to the basal layer (pH 6.9). This is also seen in the vagina where a pH of less than 4.7 protects against microbial overgrowth.

The urine may have a variable pH from acid to alkaline depending on the need for balancing the internal environment. Foods can be categorized by the potential renal acid loads.

• Fruits, vegetables, fruit juices, potatoes, and alkali-rich and low phosphorus beverages (red and white wine, mineral soda waters) having a negative acid load.
• Whereas, grain products, meats, dairy products, fish, and alkali poor and low phosphorus beverages (e.g., pale beers, cocoa) have relatively high acid loads.

How your body maintains a healthy and stable blood pH

The pH of blood is about 7.4 (a slightly alkaline range of 7.35 to 7.45). Your blood pH is highly stable within a normal range of pH 7.35 to 7.45 and it’s tightly regulated by your kidneys and respiratory system. The primary pH buffering system in the human body is the bicarbonate (HCO₃^–) and carbon dioxide (CO₂). Bicarbonate (HCO₃^–) functions as an alkalotic substance. Carbon dioxide (CO₂) functions as an acidic substance. Therefore, an increase in serum bicarbonate (HCO₃^–) or a decrease in CO₂ (carbon dioxide) will make blood more alkaline. The opposite is also true where decreases in bicarbonate (HCO₃^–) or an increase in carbon dioxide (CO₂) will make blood more acidic. Acidosis also called acidemia is a condition in which there is a shift in the acid-base balance of your body to have more acid than normal, often causing the pH of your blood and body tissues to fall below pH 7.35 (the healthy normal range of pH is between 7.35-7.45, with the average at 7.40). Acidosis occurs when acid builds up or when bicarbonate [HCO3^–] (a base) is lost. The carbon dioxide (CO₂) levels are physiologically regulated by the pulmonary system through respiration, whereas the serum bicarbonate (HCO₃^–) levels are regulated through your kidneys by two mechanisms: bicarbonate [HCO₃^–] (a base) reclamation mainly in the proximal tubule and bicarbonate [HCO₃^–] (a base) generation predominantly in the distal nephron. Elevated pH above 7.45 and elevated plasma bicarbonate (HCO₃^–) level above 30 meq/L characterize metabolic alkalosis. When bicarbonate (HCO₃^–) is elevated the arterial partial pressure of carbon dioxide (PaCO₂) must also be elevated to maintain pH to its normal range. Therefore with metabolic alkalosis, the compensation is to decrease alveolar ventilation (hypoventilation) in order to increase the arterial partial pressure of carbon dioxide (PaCO₂).

To understand acid-base buffering system, it is important to recall that pH is governed by the ratio bicarbonate [HCO₃^–] (a base)/arterial partial pressure of carbon dioxide (PaCO₂) (an acid). So long as the ratio is normal, pH will be normal.

Normal body functions and metabolism generate large quantities of acids that must be neutralized and/or eliminated to maintain blood pH balance. Most of the acid is carbonic acid (H₂CO₃), which is created from carbon dioxide (CO₂) and water (H₂O). Carbon dioxide (CO₂) is produced as the body uses glucose (sugar) or fat for energy. In its normal state, the body maintains carbon dioxide (arterial partial pressure of carbon dioxide [PaCO₂]) in a well-controlled range from 35 to 45 mm Hg by balancing its production and elimination. Lesser quantities of lactic acid, ketoacids, and other organic acids are also produced.

• Carbon dioxide (CO₂) + water (H₂O) -> H₂CO₃ (carbonic acid) -> HCO₃^– + H⁺

According to the Henderson-Hasselbalch equation (Figure 1), maintaining physiological pH depends on arterial partial pressure of carbon dioxide (PaCO₂), which in turn depends on alveolar ventilation (hypoventilation causes acidosis and hyperventilation causes alkalosis). The kidneys participate in maintaining the stable pH by reabsorption of bicarbonate (3,600 mmol of bicarbonate is filtrated in glomeruli during 24 hour) and excretion of hydrogen ions from nonvolatile acids (including sulfur and phosphate) as titratable acidity (0.3 mmol hydrogen ions/kg/day) and in the form of ammonium ion (0.7 mmol hydrogen ions/kg/day) ³³, ³⁴.

Serum bicarbonate (HCO₃^–) concentration can be calculated from a blood gas sample using the Henderson-Hasselbalch equation, as follows (see Figure 1 below):

• pH = 6.10 + log (HCO₃^– ÷ 0.03 × PaCO2)
• Alternatively, bicarbonate (HCO₃^–) = 24 × PaCO₂ ÷ [H⁺]

Because pH and arterial partial pressure of carbon dioxide (PaCO₂) are directly measured, bicarbonate (HCO₃^–) can be calculated.

Another means of assessing serum bicarbonate (HCO₃^–) concentration is with the total carbon dioxide content in serum, which is routinely measured with serum electrolytes obtained from venous blood. In this method, a strong acid is added to serum, which interacts with bicarbonate in the serum sample, forming carbonic acid. Carbonic acid dissociates to carbon dioxide and water; then, carbon dioxide is measured.

Note that the carbon dioxide measured includes bicarbonate and dissolved carbon dioxide. The contribution of dissolved carbon dioxide is quite small (0.03 × PaCO₂) and is usually ignored, although it accounts for a difference of 1-3 mEq/L between the measured total carbon dioxide content in venous blood and the calculated bicarbonate in arterial blood. Thus, at an arterial partial pressure of carbon dioxide (PaCO₂) of 40, a total carbon dioxide (CO₂) content of 25 means a true bicarbonate concentration of 23.8 (ie, 25 – 0.03 × 40).

Your lungs and kidneys are the major organs involved in regulating blood pH. And to compensate for the metabolic acidosis, you increase your breathing rate (hyperventilation) to increase carbon dioxide (CO₂) elimination ³⁵, ³⁶.

1. The lungs flush acid out of your body by exhaling carbon dioxide (CO₂). Raising and lowering the respiratory rate alters the amount of carbon dioxide (CO₂) that is breathed out, and this can affect blood pH within minutes ³⁷.
2. The kidneys excrete acids in the urine, and they regulate the concentration of bicarbonate (HCO3^–, a base) in blood. Acid-base changes due to increases or decreases in bicarbonate [HCO3^–] concentration occur more slowly than changes in carbon dioxide (CO₂), taking hours or days. Bicarbonate (HCO₃^–) reabsorption occurs in the kidneys in every part of the tubules. About 85–90% of the filtered bicarbonate is reabsorbed in the proximal tubules, 10% in the ascending arms of the Henle loop, 6% in the distal tubules, and 4% in the collecting tubules ³³, ³⁴.

Both of these processes are always at work, and they keep the blood pH in healthy people tightly controlled. The absolute quantities of acids or bases are less important than the balance between the two and its effect on blood pH.

Buffering systems that resist changes in pH also contribute to the regulation of acid and base concentrations. The main buffers in blood are hemoglobin (in red blood cells), plasma proteins, carbon dioxide (CO₂), bicarbonate (HCO₃^–) and phosphates.

Carbon dioxide (CO₂) plays a remarkable role in the human body mainly through pH regulation of the blood. The pH is the primary stimulus to initiate ventilation. In its normal state, the body maintains carbon dioxide (CO₂) in a well-controlled range from 38 to 42 mm Hg by balancing its production and elimination. In a state of hypoventilation (breathing that is too shallow or too slow to meet the needs of the body), the body produces more carbon dioxide (CO₂) than it can eliminate, causing a net retention of carbon dioxide (CO₂). The increased carbon dioxide (CO₂) is what leads to an increase in hydrogen ions (H⁺) and a slight increase in bicarbonate (HCO₃^–), as seen by a right shift in the following equilibrium reaction of carbon dioxide:

• Carbon dioxide (CO₂) + water (H₂O) -> H₂CO₃ (carbonic acid) -> HCO₃^– + H⁺

The buffer system created by carbon dioxide consists of the following three molecules in equilibrium: carbon dioxide (CO₂), H₂CO₃ (carbonic acid), and bicarbonate (HCO₃^–). When hydrogen ions (H⁺) is high, bicarbonate (HCO₃^–) buffers the low pH. When hydroxide (OH^–) is high, H₂CO₃ (carbonic acid) buffers the high pH. In respiratory acidosis, the slight increase in bicarbonate  (HCO₃^–) serves as a buffer for the increase in hydrogen ions (H⁺), which helps minimize the drop in pH. The increase in hydrogen ions inevitably causes the decrease in pH, which is the mechanism behind metabolic acidosis.

Figure 1. Henderson-Hasselbalch equation

[Source ³⁸ ]

Figure 2. Acid-base buffering system

Figure 3. Kidneys control of plasma bicarbonate (HCO₃^–)

Abbreviations: CCD = cortical collecting duct; IMCD = inner medullary collecting duct

[Source ³⁴ ]

Respiration

The pulmonary system adjusts pH using carbon dioxide (CO₂); upon expiration, carbon dioxide (CO₂) is projected into the environment. Due to carbon dioxide (CO₂) forming carbon dioxide (CO₂) in the body when combining with water (H₂O), the amount of carbon dioxide (CO₂) expired can cause pH to increase or decrease. When the respiratory system is utilized to compensate for metabolic pH disturbances, the effect occurs in minutes to hours ³⁹.

Renal adaptation

The renal system affects pH by reabsorbing bicarbonate (HCO₃^–) and excreting fixed acids ³⁹, ⁴⁰. Whether due to pathology or necessary compensation, the kidney excretes or reabsorbs these substances which affect pH. The nephron is the functional unit of the kidney. Blood vessels called glomeruli transport substances found in the blood to the renal tubules so that some can be filtered out while others are reabsorbed into the blood and recycled. This is true for hydrogen ions and bicarbonate. If bicarbonate (HCO₃^–) is reabsorbed and/or acid is secreted into the urine, the pH becomes more alkaline (pH increases). When bicarbonate (HCO₃^–) is not reabsorbed or acid is not excreted into the urine, pH becomes more acidic (pH decreases). The metabolic compensation from the renal system takes longer to occur, days rather than minutes or hours.

The renal adaptations are extensive ⁴¹:

• Increased urinary excretion of sulfate, phosphate, urate, and chloride;
• Increased urinary excretion of calcium;
• Decreased urinary excretion of citrate;
• Increased urinary excretion of ammonium ions; and
• Kidney vasodilatation and increased glomerular filtration rate.

The kidneys mitigate but do not eliminate all the excess acidity. As the kidneys lose function with aging (when GFR is lower than 30 mL/min/1.73 m²), their ability to excrete acid becomes impaired, which may be another explanation for the loss of bone with aging ⁴². In fact, counteracting metabolic acidosis helps to preserve muscle mass and to improve bone metabolism ⁴³, ⁴⁴, ⁴⁵.

Bone for acid buffering

The major reservoir of base is the skeleton (in the form of alkaline salts of calcium), which provides the buffer needed to maintain blood pH and plasma bicarbonate concentrations when renal and respiratory adaptations are inadequate. Acid-promoting diets are associated with increased urinary excretion of both calcium and bone matrix protein and decreased bone density ⁴⁶. Neutralizing acid intake with diet or alkalinizing supplements decreases urine Calcium and bone matrix protein excretion. Also, to a much smaller degree, skeletal muscle can act as a buffer.

Other buffer systems

Other buffer systems in the human body include the phosphate buffer system, proteins, and hemoglobin. All of these contain bases which accept hydrogen ions which keep the pH from plummeting. The phosphate buffer system, while present globally, is important for the regulation of urine pH. Proteins assist with intracellular pH regulation. Red blood cells use the reaction above to help hemoglobin buffer; carbon dioxide can diffuse across red blood cells and combine with water. This alone would cause an increase in hydrogen ions; however, hemoglobin can bind hydrogen ions. Hemoglobin also can bind carbon dioxide without this reaction. This depends on the amount of oxygen that is bound to hemoglobin. This is called the Haldane effect and the Bohr effect. When hemoglobin is saturated with oxygen, it has a lower affinity for carbon dioxide (CO₂) and hydrogen ions and is able to release i

The Alkaline Diet: Is There Evidence That an Alkaline pH Diet Benefits Health?

There is some good news for fans of alkaline eating. The Alkaline Diet is a plant-based and discourages added sugar, so it may help your weight and health, although not because of the pH. People who eat balanced, plant-based diets tend to have lower risks of chronic diseases like high blood pressure and diabetes. There is also research indicating that vegetarian diets may lead to lower risk for some types of cancer. However it is not clear yet if these lower cancer rates are due to diet alone, or other lifestyle factors that often go in tandem with plant-based diets (like not smoking).

As for weight, a diet rich in whole grains and fruits and veggies, and low in processed foods may be a good way to get or stay slim, however you’ll still need to pay attention to portion sizes, total calorie intake and exercise regularly.

• Chronic Acidosis and Bone Disease

There is online information promoting an alkaline diet for bone health as well as a number of books. However, a recent systematic review of the literature looking for evidence supporting the alkaline diet for bone health found no protective role of dietary acid load in osteoporosis  ⁴⁷.

There is evidence that in healthy humans the increased sodium in the diet can predict the degree of hyperchloremic metabolic acidosis when consuming a net acid producing diet ⁴⁸. As well, there is evidence that there are adverse effects of sodium chloride in the aging population. A high sodium diet will exacerbate disuse-induced bone and muscle loss during immobilization by increasing bone resorption and protein wasting ⁴⁹. Excess dietary sodium has been shown to result in hypertension and osteoporosis in women ⁵⁰, ⁵¹. As well, dietary potassium which is lacking in the modern diet would modulate pressor and hypercalciuric effects of excess of sodium chloride ⁵².

Excess dietary protein with high acid renal load may decrease bone density if not buffered by ingestion of supplements or foods that are alkali rich ⁵³. However, adequate protein is necessary for prevention of osteoporosis and sarcopenia; therefore, increasing the amount of fruit and vegetables may be necessary rather than reducing protein ⁵⁴.

• Alkaline Diets and Muscle

As we age, there is a loss of muscle mass, which may predispose to falls and fractures. A three-year study looking at a diet rich in potassium, such as fruits and vegetables, as well as a reduced acid load, resulted in preservation of muscle mass in older men and women ⁵⁵. Conditions such as chronic renal failure that result in chronic metabolic acidosis result in accelerated breakdown in skeletal muscle ⁵⁶. Correction of acidosis may preserve muscle mass in conditions where muscle wasting is common such as diabetic ketosis, trauma, sepsis, chronic obstructive lung disease, and renal failure ⁵⁷. In situations that result in acute acidosis, supplementing younger patients with sodium bicarbonate prior to exhaustive exercise resulted in significantly less acidosis in the blood than those that were not supplemented with sodium bicarbonate ⁵⁸.

• Alkaline Supplementation and Growth Hormone

It has long been known that severe forms of metabolic acidosis in children, such as renal tubular acidosis, are associated with low levels of growth hormone with resultant short stature. Correction of the acidosis with bicarbonate ⁵⁹ or potassium citrate ⁶⁰ increases growth hormone significantly and improved growth. The use of enough potassium bicarbonate in the diet to neutralize the daily net acid load in postmenopausal women resulted in a significant increase in growth hormone and resultant osteocalcin ⁶¹. Improving growth hormone levels may improve quality of life, reduce cardiovascular risk factors, improve body composition, and even improve memory and cognition  ⁶². As well this results in a reduction of urinary calcium loss equivalent to 5% of bone calcium content over a period of 3 years ⁶³.

• Alkaline Diet and Back Pain

There is some evidence that chronic low back pain improves with the supplementation of alkaline minerals ⁶⁴. With supplementation there was a slight but significant increase in blood pH and intracellular magnesium. Ensuring that there is enough intracellular magnesium allows for the proper function of enzyme systems and also allows for activation of vitamin D ⁶⁵. This in turn has been shown to improve back pain ⁶⁶.

• Alkalinity and Chemotherapy

The effectiveness of chemotherapeutic agents is markedly influenced by pH. Numerous agents such as epirubicin and adriamycin require an alkaline media to be more effective. Others, such as cisplatin, mitomycin C, and thiotepa, are more cytotoxic in an acid media ⁶⁷. Cell death correlates with acidosis and intracellular pH shifts higher (more alkaline) after chemotherapy may reflect response to chemotherapy ⁶⁸. It has been suggested that inducing metabolic alkalosis may be useful in enhancing some treatment regimes by using sodium bicarbonate, carbicab, and furosemide ⁶⁹. Extracellular alkalinization by using bicarbonate may result in improvements in therapeutic effectiveness ⁷⁰. There is no scientific literature establishing the benefit of an alkaline diet for the prevention of cancer at this time.

Conclusion

Alkaline diets result in a more alkaline urine pH and may result in reduced calcium in the urine, however, as seen in some recent reports, this may not reflect total calcium balance because of other buffers such as phosphate. There is no substantial evidence that this improves bone health or protects from osteoporosis.

Alkaline diets may result in a number of health benefits as outlined below ⁷¹:

• Increased fruits and vegetables in an alkaline diet would improve the K/Na ratio and may benefit bone health, reduce muscle wasting, as well as mitigate other chronic diseases such as hypertension and strokes. There is some evidence that the K/Na ratio does matter and that the significant amount of salt in our diet is detrimental.
• The resultant increase in growth hormone with an alkaline diet may improve many outcomes from cardiovascular health to memory and cognition.
• An increase in intracellular magnesium, which is required for the function of many enzyme systems, is another added benefit of the alkaline diet. Available magnesium, which is required to activate vitamin D, would result in numerous added benefits in the vitamin D apocrine/exocrine systems.
• Alkalinity may result in added benefit for some chemotherapeutic agents that require a higher pH.

From the evidence outlined above, it would be prudent to consider an alkaline diet to reduce morbidity and mortality of chronic disease that are plaguing our aging population. One of the first considerations in an alkaline diet, which includes more fruits and vegetables, is to know what type of soil they were grown in since this may significantly influence the mineral content. At this time, there are limited scientific studies in this area, and many more studies are indicated in regards to muscle effects, growth hormone, and interaction with vitamin D.

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