Over the years, many extreme diets have grown in popularity by appealing to people’s desire to rapidly lose weight or instantly increase physical health. While many of these diets may offer short term weight loss to healthy individuals, the lack of nutrition makes long term use of such diets an issue for those with chronic disease, such as cancer. Research suggests that implementation of a very low calorie diet or restricted calorie diet is beneficial in the treatment and prevention of cancer.
In very low calorie and restricted calorie diets, individuals significantly reduce caloric intake while maintaining the recommended daily allowance of macro and micro nutrient levels. Veronica Pons of Spain’s Olympic Training Center, Sport Nutrition and Physiology Dept, points out that, “reducing energy intake (calories) while maintaining nutrition, so-called caloric restriction, is one of the most robust interventions for increasing lifespan in a variety of species of insects and rodents, as well as in Rhesus monkeys and for inhibiting and delaying the onset of most age-related diseases” (Pons et al.
). A very low calorie or restricted calorie diet is best suited for individuals looking to reduce the likelihood of developing cancer, individuals with cancer looking to assist existing anticancer therapies, as well as individuals with cancer looking to maintaining nutrition and increasing over all physical fitness.
A very low calorie or restricted calorie diet is an effective way for individuals to reduce their chances of developing chronic disease and cancer. In a 2017 study, Dr. Ciara H O’Flanagan, a PhD in Cancer Biology at the University of North Carolina, Chapel Hill, observed that a calorie restricted diet in mice “displayed a 75.
5% reduction in tumor incidence” (O’Flanagan, et al.). In the study, Dr. O’Flanagan injected mice with tumor cells and observed their progress while administering a calorie restricted diet. The study concluded that dietary restrictions were an inexpensive anticancer therapy that reduced inflammation as well as improved metabolism. Although the study was conducted on mice and not humans, the difference in tumor development is staggering, and highlights the benefits of a very low calorie or restricted calorie diet in aiding chronic disease prevention. Additionally, Dr. Ciara O’Flanagan makes note of “longitudinal studies at the National Institute of Ageing and the University of Wisconsin showed a significant reduction in the incidence of cancers in rhesus monkeys fed a CR diet compared to a control diet” (O’Flanagan, et al.). Therefore, based on research conducted on mice and rhesus monkeys, an individual seeking to decrease his or her chances of developing cancer should consider a very low calorie diet as an essential, low cost method of cancer prevention and reduction.
In addition to reducing an individual’s chances of developing various cancers, a very low calorie or calorie restricted diet is complementary therapy to the existing anticancer treatments a cancer patient may employ including chemotherapy and radiation. For example, Dr. O’Flanagan observed that using “intermittent fasting” (or spacing meal time) as a method of introducing a very low calorie diet to the mice “had been shown to enhance treatment with both chemotherapy and radiation therapy” (O’Flanagan, et al.). These finding are encouraging for individuals experiencing an advanced stage of cancer and where cytoxic treatments are necessary. Furthermore, in a separate study, Shilpa Joshi of the Department of Nutrition & Dietetics, Mumbai Diet & Health Centre, reported the effects of a very low calorie diet as “leading to remission of type 2 diabetes” (Joshi and Mohan). Although, type 2 diabetes acts immensely different than cancer in the body, the claim is significant because “most cancer cells require higher levels of glucose than normal cells to proliferate and survive” (Ho et al.). this means that both type 2 diabetes and cancer can be combated by dramatically reducing glucose availability to cells. Furthermore, according to O’Flanagan, “in response to decreased caloric intake, metabolic alterations foster health promoting characteristics, including increased insulin sensitivity and decreased blood glucose” (O’Flanagan, et al.). Ultimately, the studies suggest that the advantage observed in a very low calorie or restricted calorie diet that contribute to regulating type 2 diabetes and by decreasing blood glucose are also beneficial to cancer patients by reducing the availability of glucose for cancer cells to proliferate or metastasize.
While chronic disease prevention and assisting in the efficacy of existing cancer therapies are both important consequences of a very low calorie or restricted diet, ultimately, maintaining an individual’s recommended daily nutrition levels and increasing overall physical fitness is the most influential feature of a very low calorie diet in relation to cancer. It is vital for a cancer patient to maintain the recommended daily values of micro and macro nutrients to maintain physical health and a healthy body weight. As noted by Shilpa Joshi in a study conducted in Mumbai, India, “obesity leads to type 2 diabetes, hypertension, cardiovascular disease, non-alcoholic fatty liver disease, cholelithiasis, osteoarthritis, sleep apnoea and even some forms of cancer” (Joshi and Mohan). For those seeking reduce development of cancer and other chronic diseases, weight management and proper nutrition are vital component of physical health. In the same study, a very low calorie diet “lead to rapid weight loss. Lean body mass is preserved by providing adequate dietary protein in the form of milk, soy or egg-based powder which is mixed with water and consumed as a liquid. Such diets provide 80g carbohydrate and 15g fat per day. Recommended daily allowance (RDA) of essential vitamins and minerals is also ensured” (Joshi and Mohan). In order for an individual to fully utilize the benefits of a very low calorie or restricted calorie diet there must also be an emphasis on maintaining recommended daily allowance of all macro and micro nutrients increase therapeutic advantages and to prevent malnutrition. Having the appropriate amount of nutrition is essential for any individual regardless of the presence of chronic disease
Many researchers believe that ketogenic diets are more effective in preventing chronic disease than a very low calorie or restricted calorie diet. While this may be true in the short term, evidence suggests that very low calorie or calorie restricted diet is the most beneficial for long term use, as well as, for treatment of a variety of disease other than cancer. Consequently, an argument against the very low calorie diet theory comes from Dr. O’Flanagan where she states that a “chronic calorie restriction is challenging to employ in cancer patients, and therefore intermittent fasting, calorie restricted mimetic drugs, or alternative diets (such as a ketogenic diet or low carbohydrate diets), may be more suitable” (O’Flanagan, et al.). On the other hand, Dr. O’Flanagan used the method of ‘intermittent fasting’ in her research as a way to implement a calorie restricted diet in mice, which lead to reduction in the occurance of tumors. A ketogenic diet consists of limiting the intake of carbohydrates and increasing the intake of protein and fats. Considering the relationship between carbohydrates, sugars and glucose a ketogenic diet offers similar benefits to individuals with cancer by limiting the available glucose for cancer cells that helps cancer cells proliferate. Conversely, in an analysis of ketogenic diets, A. Paoli of The Physiological Laboratory, Department of Biomedical Sciences, University of Padova, in Italy, claims that “authors have subsequently stated instead that dietary protein restriction is neither necessary nor useful over the long term” (Paoli, A, et al.). This empasiszes that a ketogenic diet is not meant to be a long term dietary option. Moreover, with the support of family and medical professionals an individual with cancer can maintain a very low calorie diet or calorie restricted diet just as easily as maintaining a ketogenic diet. Furthermore, if using a very low calorie diet produces the same effects as a prescription drugs, one would assume a diet that reduces the dependency on pharmaceuticals would be preferred over taking a prescription drug. Additionally, Shilpa Joshi writes that “instead of resorting to such extreme diets, correction of obesity is best achieved with balanced, healthy, nutritious diets which are low in calories, combined with adequate physical activity” (Joshi and Mohan). While this claim over simplifies the steps necessary for already healthy individuals to maintain health, it does not account for dietary needs of a cancer patient undergoing anticancer therapies.
In conclusion, there is substantial research on very low calorie and restricted calorie diets and the benefits in regards to cancer. The focal point of the evidence, is in the accompaniment of a very low calorie diet and with anticancer treatments, and as a means to reduce occurrence of malignant tumors. While a very low calorie or restricted calorie diet may be seen as an extreme diet, one cannot discount its effectiveness as a low cost anticancer therapy. The anticancer benefits observed in mice, rhesus monkeys and human is a result of glucose reduction at the cellular level. In addition, researchers claim that “calorie restriction (CR) is the most effective and reproducible intervention for increasing lifespan in a variety of animal species, including mammals. Dr. Hursting, a Professor in the Department of Nutrition and the Lineberger Comprehensive Cancer Center at the University of North Carolina at Chapel Hill continues that “calorie restriction is also the most potent, broadly acting cancer-prevention regimen in experimental carcinogenesis models” (Hursting et al.). Finally, when implemented correctly, a very low calorie or restricted calorie diet has been proven to maintain micro and macro nutrient levels, increase overall physical fitness, reduce body weigh, prevents proliferation in tumors as well as improves effectiveness of cytoxic cancer treatments (such as chemotherapy and radiation therapy). Health minded individuals that seek to prevent chronic disease and maintain health should consider implementing a very low calorie or calorie restricted diet along with regular physical activity to utilize ultimate health benefits.