February 2021 Issue
CPE Monthly: Cancer and the Alkaline Diet — Making Sense of the Hype
By Dianne Piepenburg, MS, RD, CSO
Vol. 23, No. 2, P. 44
Suggested CDR Performance Indicators: 4.1.2, 4.2.5, 6.2.5, 8.1.3
CPE Level 2
A cancer diagnosis often is associated with a multitude of feelings, including a loss of control. This can lead patients to look for treatment beyond traditional cancer therapies; they may reach out to friends, family, or other health practitioners, or search bookstores and the internet. As a result, they may receive a significant amount of information regarding many complementary and alternative treatments.
One common alternative cancer therapy is the alkaline diet. A Google search for “alkaline diet and cancer” results in millions of links, including websites for authors trying to sell their books and companies attempting to sell their products. Because this information can seem like a viable alternative for treating or curing a disease, it’s crucial that patients receive proper guidance from a nutrition professional who can help them sort the truth from the fallacy using evidence-based guidelines.
This continuing education course examines the relationship between cancer and the alkaline diet. It reviews the basics of metabolism and identifies differences between normal cellular metabolism and cancer cell metabolism, within the concept of pH balance. This course also will highlight common alkaline diet restrictions and compare those with evidence-based recommendations.
Efficacy of the Alkaline Diet
The alkaline diet is based on the premise that eating or avoiding certain foods can alter one’s systemic, or internal, pH, and that this may reduce, prevent, or cure various diseases. While no standardized alkaline diet exists, many companies and authors base their recommendations off the potential renal acid load table developed by researchers Remer and Manz.1 Using this table, authors have written their own versions of the alkaline diet, and companies have used this research to sell various products, including water treatment machines and urine and/or saliva litmus test strips.2
A common theme in the alkaline diet includes avoidance of animal-based proteins such as meat and dairy products. These foods are considered acidic due to the high amount of acid byproducts they send to the kidneys. Other foods some sources recommend avoiding include plant-based items such as potatoes, beans, simple sugars, and most grains.2
Research studying the alkaline diet’s possible benefits for cancer and other conditions has been ongoing for decades. The alkaline diet usually is discussed in opposition to the typical Western diet, which is considered “acidogenic.”
A review article by Robey describes an acidogenic diet as one that’s rich in animal proteins, salt, sugar, and fat and deficient in alkaline/base-forming foods such as fruits and vegetables. According to this theory, acidogenic diets induce hormonal changes such as upregulation of insulinlike growth factor 1, cortisol, leptin, and adiponectin, which are thought to then increase the body’s acidity. However, Robey concludes, while a Western-type diet may increase the acid load sent to the kidneys, it hasn’t been proven that these hormonal changes directly increase cancer risk. Furthermore, Robey asserts that patients shouldn’t modify their diet based solely on the perception that doing so will provide benefit.3
In a similar review article by Schwalfenberg investigating the alkaline diet’s relationship to cancer and other disease states, the author identifies long-term changes to dietary habits that have resulted in an eating pattern with less fiber and more saturated fat, simple sugars, sodium, and chloride. These changes have resulted in greater consumption of sodium vs potassium and an increase in chloride vs bicarbonate, which may be responsible for a diet-induced chronic acidotic state. Schwalfenberg says dietary habits don’t affect one’s internal pH but that they do change urinary pH and questions whether this shift may be detrimental to one’s health.4
With regard to cancer, it’s discussed that while certain chemotherapies (including epirubicin and Adriamycin) may be more effective in an alkaline environment, others (such as cisplatin and mitomycin C) are more effective in an acidic environment. The consensus is that current scientific literature doesn’t support a benefit of an alkaline diet for cancer prevention or treatment.4
In a systematic review by Fenton and Huang, only one study out of 8,278 on the alkaline diet and cancer met inclusion criteria. This study, which looked at urine pH and compared it with the incidence of bladder cancer, concluded that urine pH isn’t an identifiable risk factor for bladder cancer.5 These findings correlate with what’s known about the body’s ability to tightly regulate pH balance through a combination of respiratory, renal, and chemical buffers.6
In addition to having limited to no support, the alkaline diet comes with possible harms. Depending on the type of alkaline diet followed, there’s a risk of micronutrient deficiencies with long-term use. Because this diet typically restricts major food groups, including meat, nuts, seeds, dairy, and certain fruits, vegetables, and grains, it may be deficient in important vitamins and minerals, including iron, B vitamins, calcium, and vitamin D.
A recent systematic review identified that individuals who consumed a strict vegetarian diet, similar to that of an alkaline diet, had lower iron store levels than nonvegetarians.7 In one case study, an individual who followed a very restrictive, primarily vegan diet experienced protein-calorie malnutrition and pellagra. Symptoms resolved with supplementation and consumption of the identified deficient micronutrients.8
Basic Cellular Metabolism and Alkalinity/Acidity
To understand the rationale behind using the alkaline diet as an alternative cancer treatment, it’s important to first review the basics of normal cellular metabolism and compare that process with the metabolic alterations that occur in cancer cells. This comparison sheds light on what makes the diet appear to consumers to be a plausible treatment, identifies the theory behind the diet’s flaws, and makes it possible to understand the rationale for using evidence-based diet recommendations for patients with cancer.
The process of energy production in a normal cell begins within the cytoplasm. This is called glycolysis, and this process uses glucose to create the substrate necessary for energy. In the presence of oxygen (ie, an aerobic state), this substrate (ie, pyruvate) enters the mitochondria to generate the maximum amount of energy.9
When a cell is deprived of oxygen (ie, an anaerobic environment), the cell’s ability to efficiently produce and use energy is hindered. In this environment, pyruvate isn’t transported into the mitochondria for further conversion to energy. Instead, it’s converted into lactate (ie, acid).10 Scientists have theorized that overproduction of this acid plays a part in cancer cell proliferation.
Approximately 100 years ago, it was thought that cancer cells produced greater amounts of lactate than healthy cells, even in the presence of oxygen. Scientists at that time thought that in order for cancer cells to grow and divide, lactate would be transported from inside the cell to outside the cell. This would provide an environment within the cell that enables efficient growth and replication of more cancer cells, and the lactate outside the cell would make one’s body more acidic. This theory is known today as the Warburg Effect, named after the Nobel Prize–winning German scientist Dr. Otto Warburg.11,12
Warburg sought to better understand cells’ use of energy and was instrumental in helping researchers begin to understand the cellular workings of cancer. However, it’s now known that cancer cell metabolism is considerably more complex than Warburg theorized.12 While it seems logical that a cancer patient’s body is more acidic because cancer cells produce and excrete lactate, this isn’t the case. Under both cancerous and normal conditions, the body maintains its pH within a very small, near-neutral range—approximately 7.35 to 7.45—despite the complex processes it continually undergoes (eg, eating, drinking, respiration, digestion, elimination).
During extreme conditions—such as restrictive lung diseases, diabetic ketoacidosis, or disturbances of the central nervous system, which interrupt the body’s ability to maintain homeostasis—pH may be altered and result in an acidotic or alkalotic state (either respiratory or metabolic). In these cases, medical attention, including hospitalization, may be required to restore pH balance.13
Nutrition Recommendations for Cancer Prevention
Nutrition professionals are well aware of the challenges to performing high-quality, evidence-based nutrition research, such as the inability of an individual to consume only one food or take one supplement. Many studies also rely on subjective information such as food frequency questionnaires or diet histories, which may or may not be accurate representations of actual intakes. These factors and others increase the difficulty in determining which foods may be beneficial or harmful to health. Despite these challenges, research has been ongoing for decades to determine whether and how what we eat affects our health.
The American Institute for Cancer Research (AICR), the World Cancer Research Fund (WCRF), and the American Cancer Society (ACS), are three prominent organizations that continuously seek to perform and review the latest research regarding cancer and nutrition.14,15 Research findings from these organizations, and their subsequent recommendations, are considered the gold standard and have identified diet as one of the cornerstones of cancer prevention.
The AICR/WCRF estimate that approximately 40% of cancers may be preventable by incorporating their recommended diet and lifestyle practices. These organizations’ guidelines don’t focus on “alkaline” or “acidic” foods but are based on high-quality research and encourage consumption of a wide variety of foods. Also, they’re intended not only for cancer prevention but also to reduce risk of other diseases, including diabetes and CVD.16,17
Limiting Processed Meat and Red Meat
The alkaline diet includes avoidance of all meat due to the belief that it produces acidic byproducts that may negatively impact one’s health. The AICR/WCRF and ACS also indicate there’s evidence to support an increased risk of adverse outcomes with consumption of red and processed meat. However, current research doesn’t suggest a need to eliminate all meat, nor all red meat.
The recommendation to limit consumption of red meat (eg, beef, pork, lamb) came, in part, as a result of the large, prospective National Institutes of Health–AARP Diet and Health Study, which identified a correlation between red meat intake and increased risk of cancer.18 Of the approximately 500,000 participants, a statistically significant 20% to 60% increased risk was evident for cancers of the esophagus, liver, colon and rectum, and lung in those who consumed the most red meat vs the least. In addition, higher intakes of processed meat (eg, lunchmeat, sausage, bacon) were associated with increased risk of colorectal (20%) and lung (16%) cancers.19
Subsequent studies have confirmed these risks in those with a history of colorectal cancer. These research findings have led to the conclusion that a diet pattern including a high intake of red meat decreases survival rates in individuals with a previous diagnosis of stage III colorectal cancer.20
Research has found that one doesn’t have to avoid red meat entirely, but it’s recommended to reduce consumption, as evidence has shown that a high intake of red and processed meat is associated with poorer health outcomes. While a diet rich in red meat may increase one’s risk of certain cancers, it isn’t recommended to limit intake due to the acid it produces within the body.
The mechanisms of the relationship between red meat and cancer risk aren’t known, but the association is thought to be partly due to the saturated fat, heme iron, and mutagens within these foods. Due to its caloric density, saturated fat contributes to increased calorie consumption, thereby increasing one’s risk of overweight or obesity. It’s thought that heme iron plays a role in carcinogenesis by increasing free radical production and oxidative stress. Mutagens, including N-nitroso compounds (NOCs), heterocyclic amines (HCAs), and polyaromatic hydrocarbons (PAHs), also are thought to increase risk of malignancy.18
NOCs are associated with red, cured, and processed meats (eg, salted or smoked) and have been found to increase risk of colorectal cancer and esophageal cancer. PAHs and HCAs develop when red meat is cooked at a high temperature. Therefore, the increase in the body’s acidity isn’t the risk factor for cancer; rather, it’s the changes in body composition and formation of these potentially harmful byproducts that may increase one’s risk of adverse health effects.18
Red meat is a rich source of many nutrients, including protein and iron, making some intake potentially beneficial to one’s health. However, the AICR/WCRF recommend limiting one’s intake to no more than 12 to 18 oz per week and avoiding consumption of processed meats altogether.21 The ACS doesn’t identify a quantity to limit one’s red or processed meat intake but encourages incorporation of other proteins, including a variety of fish, poultry, and beans.17
Beans, nuts, seeds, and legumes also are often restricted within the alkaline diet due to the acid load they theoretically produce. However, the AICR/WCRF, ACS, and Academy of Nutrition and Dietetics (the Academy) all agree that a diet high in plant foods that’s rich in these protein sources may decrease one’s risk of cancer and other diseases.15,22,23
Restrict Sugary Drinks and Maintain a Healthy Weight
In the alkaline diet, simple sugars are considered acidic and should be avoided. The AICR/WCRF and ACS thoroughly have reviewed the large body of evidence concerning sugar and cancer and have determined that sugar consumption doesn’t increase the risk of cancer, nor has it been proven to increase the body’s acidity.24
However, there’s evidence that overconsumption of nutrient-deplete, calorie-rich foods and beverages made with simple sugars (eg, cookies, candy, soda) may result in overconsumption of calories, increasing one’s risk of overweight and obesity. Overweight and obesity are known risk factors for some cancers, including breast, colorectal, and stomach, in addition to other comorbidities, including diabetes and CVD.14,16,17
Eat a Diet Rich in Fruits and Vegetables
As discussed, there’s no standardized alkaline diet, and, depending on which version of the diet one follows, certain fruits and vegetables may be recommended to include or avoid due to their acidity or alkalinity. This can result in confusion for consumers, as they’re left without the evidence-based knowledge to make informed decisions regarding
what fruits and vegetables they should incorporate or avoid.
Surprisingly, a large prospective cohort study (>500,000 participants) found that consumption of fruits and vegetables isn’t strongly associated with an overall decreased risk of cancer.25 However, according to the AICR, more recent evidence has shown a positive association between fruit and vegetable intake and reduced breast cancer incidence. Because plant-based foods may lower risk of colorectal cancer and help maintain a healthy weight, the AICR recommends filling at least two-thirds of one’s plate with plant-based foods, including fruits and vegetables.16,26
Similarly, the Academy recognizes the healthfulness of a diet high in plant foods, including vegan and vegetarian diets. As discussed within their 2016 position paper, “appropriately planned vegetarian, including vegan, diets are healthful, nutritionally adequate, and may provide health benefits in the prevention and treatment of certain diseases.”23
Curb or Eliminate Alcohol
Alcohol typically is considered acidic, and the alkaline diet discourages consumption. In 2018, The Lancet published the findings from the Global Burden of Diseases, Injuries, and Risk Factors Study, which found that no intake of alcohol is considered safe, and even small intakes can increase the risk of various diseases, including cancer.27
The AICR/WCRF and ACS also have extensively reviewed the available literature and agree that alcohol doesn’t provide significant health benefits and increases cancer risk.15,28 The National Cancer Institute confirms these findings, stating, “Based on extensive reviews of research studies, there is a strong scientific consensus of an association between alcohol drinking and several types of cancer.”29
For this reason, AICR/WCRF and ACS suggest individuals refrain from consuming alcohol. However, for those who choose to consume alcohol, recommendations are to limit intake to one drink per day for women and two drinks per day for men. One drink may be 12 oz of beer, 5 oz of wine, or 1.5 oz of spirits (hard alcohol).15,28
Select Whole Grains vs Refined Grains
AICR/WCRF’s most recent report shows that eating whole grains every day reduces the risk of colorectal cancer, and that the more one eats, the lower their risk. Consumption of about three servings (90 g) of whole grains each day is associated with a 17% reduction in colorectal cancer risk.15,30 Interestingly, proponents of the alkaline diet consider many whole grains, including brown rice, oats, and whole wheat, to be acidic and recommend avoiding them or consuming them in limited quantities.31
That said, refined grains such as cereals, baked goods, white or enriched flour, and white rice are considered acidic and also aren’t recommended by the AICR/ WCRF or ACS because they lack dietary fiber and nutrients that may help prevent cancer. In addition, refined and processed grains also can lead to overconsumption of calories, increasing one’s risk of overweight or obesity.14,30
Reduce Intake of Salty Foods and Foods Processed With Salt
Many foods commonly consumed in the standard American diet are high in salt, including pickled foods, cured meat and fish, and some highly processed packaged items. Older evidence suggested that consuming high-sodium foods can harm the stomach lining and increase stomach cancer risk. The AICR/WCRF confirm that more recent evidence doesn’t strongly support this theory, but they still recommend limiting sodium intake to less than 2,400 mg per day.32 Furthermore, many high-sodium items are nutrient deplete, contributing to overconsumption of calories and subsequently increasing the risk of overweight or obesity.
As discussed previously, the modern diet is high in sodium and chloride and may contribute to chronic acidosis, increasing the acid load processed by the kidneys.3 However, the detriment this increased acid load may have on health hasn’t been proven.
Marketing of the Alkaline Diet
Despite the lack of evidence to support the restriction of certain foods and that the body maintains a tightly regulated pH balance, companies aren’t dissuaded from preying on consumers and touting the benefits of their versions of an alkaline diet. These companies may imply that in order for individuals to monitor their progress in making their system more alkaline, they must purchase litmus strips and use either saliva or urine to monitor their pH. The claim is that if urine or saliva pH is increased, consumers ultimately will reduce or remove harmful cancer-causing acids from their body.33
However, the pH of saliva and urine may be affected by many factors, including consumption of various foods, fluids, and medications. For example, if individuals drink orange juice or have lemon juice on their salads, testing the pH of saliva wouldn’t be an accurate measurement of their actual pH. The same is true for monitoring one’s urine pH, as it, too, is vulnerable to variations in acidity and alkalinity due to food, hydration status, kidney function, etc. Therefore, although a cancer cell’s environment may be more acidic or urine or saliva may be identified as acidic, these factors don’t make the body more acidic as a whole.
Many companies also recommend consuming alkaline water, which has undergone an ionizing process to increase its pH, instead of standard drinking water as a way to boost health and prevent or cure various diseases, including cancer.34 Certain companies may falsely identify alkaline water as superior to standard water due to the antioxidant properties incurred during this ionization process. They claim alkaline waters can destroy or inhibit the growth of cancer cells and detoxify the body and neutralize potentially harmful free radicals.
While there are references on various websites to support these claims, they usually rely on small, nonhuman, in vitro or in vivo studies. In fact, a literature review has concluded that the purported health benefits of alkaline water lack support.4 Health professionals understand they shouldn’t expect the same outcome that occurs within an in vitro or in vivo study to be replicated in humans. However, the general consumer may be unaware of this and expect the same results in their bodies.
Despite the lack of evidence behind the alkaline diet, some celebrities have embraced it, thereby influencing consumers to do so as well.35 For example, Dr. Mehmet Oz, a well-known cardiologist turned talk show host and author, claims that consumption of acidic foods can be toxic and inflammatory and increase risk of a host of diseases.36
According to information on his website, it’s possible to “negate acid’s negative effects on the body by balancing your diet with foods that promote an alkaline body environment.” The website lists 25 foods (listed from neutral to most alkaline) to incorporate into the diet, including white wine, potatoes, and draft beer (most neutral). However, Oz doesn’t identify how the diet works or what disease states it may prevent. There also are no evidence-based resources available to support his recommendations.
Putting It Into Practice
How can health care professionals counsel clients who ask about or would like to follow an alkaline diet? First, it’s important to identify the benefits, such as incorporating ample fruits and vegetables, which are high in fiber and low in calories, and contain an abundance of vitamins and minerals, including vitamins A and C. Another positive aspect is that the diet is low in sodium, added sugars, saturated fat, and alcohol.
However, professionals should inform clients that this diet is highly restrictive and can be difficult to maintain long term. The diet also doesn’t provide adequate protein, calcium, B vitamins (especially B12), vitamin D, and iron. If individuals continue to feel strongly about following an alkaline diet, they should be educated about ways to ensure they obtain adequate nutrients. They may require vitamin/mineral supplements and/or need to incorporate plant-based proteins such as tofu or tempeh.
Discussions about the pros and cons of the alkaline diet, or other diets, can be an opportunity for dietitians to not only educate but also empower individuals who desire to make positive diet and lifestyle choices. Evidence-based diet and lifestyle recommendations may align with some aspects of the alkaline diet; however, dietitians can help clients distinguish truth from fallacy and realize that a cancer-fighting diet is more than a matter of acidic vs alkaline foods. Rather, it’s incorporation of a diet rich in a variety of foods that have shown to provide the greatest benefit.
— Dianne Piepenburg, MS, RD, CSO, is an oncology dietitian at the Malcolm Randall VA Medical Center. She’s a board member of the Academy of Nutrition and Dietetics’ Oncology Nutrition Dietetic Practice Group. Piepenburg has written various articles for publication and is coauthor of the chapter “Nutrition and the Cancer Survivor” within the text Supportive Cancer Care. She’s also been a public speaker about cancer and nutrition at the local, state, and national level.
After completing this continuing education course, nutrition professionals should be better able to:
1. Explain the premise of the alkaline diet.
2. Assess the differences between cellular, blood, and urine/saliva pH.
3. Discuss evidence that supports and refutes the alkaline diet theory.
4. Educate health professionals, patients, and the public about evidence-based dietary recommendations for cancer patients and survivors.
CPE Monthly Examination
1. According to the American Institute for Cancer Research (AICR) and World Cancer Research Fund (WCRF), approximately how many cancer deaths can be prevented by healthful diet and lifestyle habits?
2. What metabolic process occurs to produce lactic acid?
a. Overproduction of pyruvate
b. Transport of pyruvate to the mitochondria
3. What is the name of the process of lactate (eg, acid) overproduction that occurs during cancer cell metabolism and was theorized to increase the body’s acidity?
a. Ostergren effect
b. Lactate effect
c. Warburg effect
d. Pyruvate effect
4. The AICR/WCRF recommend limiting red meat intake to what amount?
a. 2 oz per day
b. 4 oz per day
c. 12 oz per week
d. 18 oz per week
5. Which of the following foods is considered acidic?
6. What is the name of the table that lists foods according to the acids or bases they produce?
a. Perceived kidney alkaline load
b. Present renal acid list
c. Potential renal acid load
d. Particulate renal injury load
7. Which nutrient may be inadequate when following the alkaline diet?
b. Vitamin A
c. Vitamin C
8. Monitoring pH using one’s saliva or urine isn’t recommended for what reason?
a. Results vary due to exercise, medications, and cardiac function.
b. It’s not an accurate marker of blood pH.
c. Results remain consistent despite changes in food intake, digestion, hydration, etc.
d. Litmus strips are difficult to use.
9. Which of the following is not a recommendation of AICR/WCRF and the American Cancer Society?
a. Incorporate a diet rich in fruits and vegetables.
b. Select whole grains instead of refined grains.
c. Consume alcohol daily; it’s acceptable to consume more than two drinks per day.
d. Limit red meat intake to 18 oz per week or less.
10. Added sugars are thought to contribute to cancer risk in what way?
a. Providing cancer cells with energy
b. Increasing the risk of consuming excess calories
c. Contributing to the Warburg Effect
d. Interfering with the metabolism of protein and fat
1. Remer T, Manz F. Potential renal acid load of foods and its influence on urine pH. J Am Diet Assoc. 1995;95(7):791-797.
2. Acid alkaline food chart. The Acid Alkaline Association Diet website. http://www.acidalkalinediet.net/acid-alkaline-food-chart.php. Accessed August 31, 2018.
3. Robey IF. Examining the relationship between diet-induced acidosis and cancer. Nutr Metab (Lond). 2012;9(1):72.
4. Schwalfenberg GK. The alkaline diet: is there evidence that an alkaline pH diet benefits health? J Environ Public Health. 2011;2012:727630.
5. Fenton TR, Huang T. Systematic review of the association between dietary acid load, alkaline water, and cancer. BMJ Open. 2016;6(6):e010438.
6. Lewis JL 3rd. Acid-base balance. Merck Manual Professional Version website. https://www.merckmanuals.com/professional/endocrine-and-metabolic-disorders/acid-base-regulation-and-disorders/acid-base-regulation. Updated January 2020. Accessed September 25, 2018.
7. Haider LM, Schwingshackl L, Hoffmann G, Ekmekcioglu C. The effect of vegetarian diets on iron status in adults: a systematic review. Crit Rev Food Sci Nutr. 2018;58(8):1359-1374.
8. Ng E, Nuff M. Recognising the return of nutrient deficiencies: a modern pellagra puzzle. BMJ Case Rep. 2018;11(1):e227454.
9. Devlin TM. Eukaryotic cell structure. In: Devlin TM, ed. Textbook of Biochemistry With Clinical Correlations. 6th ed. Hoboken, NJ: John Wiley and Sons; 2006:1-22.
10. Luengo A, Gui DY, Vander Heiden MG. Targeting metabolism for cancer therapy. Cell Chem Biol. 2017;24(9):1161-1180.
11. Koltai T. Cancer: fundamentals behind pH targeting and the double-edged approach. Onco Targets Ther. 2016;9:6343-6360.
12. Yaojie Fu, Liu S, Yin S, et al. The reverse Warburg effect is likely to be an Achilles’ heel of cancer that can be exploited for cancer therapy. Oncotargets. 2017;8(34):57813-57825.
13. Brandis K. Acid-base physiology. Anaesthesia Education website. http://www.anaesthesiamcq.com/AcidBaseBook/ABindex.php. Updated August 30, 2017. Accessed November 19, 2017.
14. Serving up better health. American Institute for Cancer Research website. https://www.aicr.org/cancer-prevention/healthy-eating/. Accessed November 24, 2017.
15. American Cancer Society guidelines for nutrition and physical activity for cancer prevention. American Cancer Society website. https://www.cancer.org/healthy/eat-healthy-get-active/acs-guidelines-nutrition-physical-activity-cancer-prevention.html/acs-guidelines-on-nutrition-and-physical-activity-for-cancer-prevention-common-questions.html. Accessed November 24, 2017.
16. Improving diet quality reduces risk for type 2 diabetes. ScienceDaily website. https://www.sciencedaily.com/releases/2014/06/140614150313.htm. Published June 14, 2014. Accessed January 18, 2020.
17. The American Heart Association diet and lifestyle recommendations. https://atgprod.heart.org/HEARTORG/HealthyLiving/HealthyEating/HealthyDietGoals/Dictionary-of-Nutrition_UCM_305855_Article.jsp. Updated August 2015. Accessed January 18, 2020.
18. Knekt P, Järvinen R, Dich J, Hakulinen T. Risk of colorectal and other gastro-intestinal cancers after exposure to nitrate, nitrite and N-nitroso compounds: a follow-up study. Int J Cancer. 1999. 80:852-856.
19. Cross AJ, Leitzmann MF, Gail MH, et al. A prospective study of red and processed meat intake in relation to cancer risk. PLoS Med. 2007;4(12):e325.
20. Meyerhardt JA, Niedzwiecki D, Hollis D, et al. Association of diet patterns with cancer recurrence and survival in patients with stage III colon cancer. JAMA. 2007;298(7):754-764.
21. Eat no more than moderate amounts of red meat, such as beef, pork, and lamb. Eat little, if any, processed meat. American Institute for Cancer Research website https://www.aicr.org/cancer-prevention/recommendations/limit-consumption-of-red-and-processed-meat/. Published 2020. Accessed October 11, 2020.
22. Pulses: dry beans, peas, and lentils (legumes). American Institute for Cancer Research website. http://www.aicr.org/foods-that-fight-cancer/legumes.html. Updated December 20, 2019.
23. Melino V, Craig W, Levin S. Position of the Academy of Nutrition and Dietetics: vegetarian diets. J Acad Nutr Diet. 2016;116(12):1970-1980.
24. The sugar and cancer connection. American Institute for Cancer Research website. http://www.aicr.org/reduce-your-cancer-risk/diet/sugar-and-cancer-risk.html. Accessed November 24, 2017.
25. Bradbury KE, Appleby PN, Key TJ. Fruit, vegetable, and fiber intake in relation to cancer risk: findings from the European Prospective Investigation into Cancer and Nutrition (EPIC). Am J Clin Nutr. 2014;100(Suppl 1):394S-398S.
26. New study links plenty of fruits, veggies with reduced risk of certain breast cancers. American Institute for Cancer Research website. https://www.aicr.org/news/new-study-links-plenty-of-fruits-veggies-with-reduced-risk-of-certain-breast-cancers/. Published August 22, 2016. Accessed January 19, 2020.
27. Burton R, Sheron N. No level of alcohol consumption improves health.
28. Limit alcohol consumption. American Institute for Cancer Research website. https://www.aicr.org/cancer-prevention/recommendations/limit-alcohol-consumption/. Accessed November 24, 2017.
29. Alcohol and cancer risk. National Cancer Institute website. https://www.cancer.gov/about-cancer/causes-prevention/risk/alcohol/alcohol-fact-sheet. Updated September 13, 2018.
30. Whole grains. American Institute for Cancer Research website. https://www.aicr.org/cancer-prevention/food-facts/whole-grains/. Updated January 2, 2020.
31. Nutrition therapy. Believe Big website. https://believebig.org/nutrition-therapy/. Accessed January 19, 2020.
32. Stomach cancer. American Institute for Cancer Research website. https://www.aicr.org/research/the-continuous-update-project/stomach-cancer/. Updated January 9, 2020. Accessed January 19, 2020.
33. Acid and alkaline food chart. Chi Machine International website. https://www.chimachine4u.com/AA.html. Accessed November 20, 2017.
34. Is there proof or scientific evidence of alkaline water benefits? Alkalinewaterionizers.org website. http://www.alkalinewaterionizers.org/is-there-proof-or-scientific-evidence-of-alkaline-water-benefits/. Accessed May 24, 2018.
35. The alkaline diet. These celebrities love it, but what are the benefits? Healthista website. https://www.healthista.com/the-alkaline-diet-what-are-the-benefits/. Published March 25, 2015. Accessed October 11, 2020.
36. 25 alkaline-promoting foods. Dr. Oz website. https://www.doctoroz.com/article/25-alkaline-promoting-foods. Accessed November 18, 2017.