The Importance of Nutrition During Cancer Treatment
The nutritional status of cancer patients is often compromised as a symptom of the cancer or as a side effect of conventional treatment (Usharani K et al 2004). Indeed, a significant number of patients recovering from cancer are malnourished (Guo Y et al 2005) or have suffered considerable weight loss (Colasanto JM et al 2005). The nutritional status of cancer patients has an impact on a variety of important factors, including:
-Survival and overall outcome
-Cancer development and progression.
Nutritional intervention as an integral (holistic) part of cancer treatment can be implemented by eating healthy foods and taking supplements
Nutritional intervention during cancer treatment may help patients to better tolerate cancer treatment, with less frequent adverse side effects (Bahl M et al 2004; Capra S et al 2001; Read JA et al 2004).
Survival and Overall Outcome.
Malnourished cancer patients are more likely to have longer periods of hospitalization, lower survival rates, and a higher frequency of medical complications (Colasanto JM et al 2005; Guo Y et al 2005).
Impaired nutritional status in cancer patients is associated with reduced numbers of white blood cells (most often neutropenia) and low red blood cell counts, or anemia (Usharani K et al 2004). Administration of a specialized formula enriched with nutrients (including arginine and omega-3 fatty acids) to cancer patients before surgery reduced the occurrence of infections and time spent in the hospital (Moskovitz DN et al 2004).
Cancer Development and Progression.
A study of patients with high levels of prostate-specific antigen (PSA), a widely accepted indicator of the risk of developing prostate cancer, showed that a diet of low fat and high soybean protein content induced a significant, though temporary, reduction in PSA levels (Tsutsumi M et al 2004).
Prevention of Cancer Development and Progression
Natural strategies known to prevent the development and progression of cancer include:
-Green and black teas
Calcium. In clinical studies involving more than 1000 colorectal cancer patients, calcium supplements reduced the risk of cancer recurrence (Shaukat A et al 2005). Other studies show that calcium supplements generally reduce the risk of developing colorectal cancer in the first place (Flood A et al 2005; Sandler RS 2005). This beneficial effect of calcium was noted for calcium obtained from both dietary sources and nutritional supplements (Flood A et al 2005).
Carotenoids. Clinical studies have found that supplementing with lycopene, a carotenoid that is abundant in tomatoes and tomato-based products, can protect against cancers of the prostate (Campbell JK et al 2004; Jian L et al 2005; Kucuk O et al 2002), colon (Nair S et al 2001), pancreas (Nkondjock A et al 2005), ovaries (Huncharek M et al 2001), breast (Toniolo P et al 2001), and bladder (Schabath MB et al 2004).
Curcumin, extracted from the spice turmeric ('kunyit'), has preventive and therapeutic anti-cancer properties (Aggarwal BB et al 2003; Sharma RA et al 2004).
Curcumin can stop the growth of cancers of the prostate (Dorai T et al 2000; Dorai T et al 2004), colon (Narayan S 2004), and breast (Inano H et al 2000).
Garlic has long been known to have anti-cancer properties (Das S 2002; Khanum F et al 2004) due to its ability to disrupt the function of cancer-causing agents (Das S 2002).
Green and Black Teas. Catechins and theaflavins, compounds found in green and black teas, have anti-cancer properties (Yang CS et al 2005).
Clinical studies have shown that consuming five or more cups a day of green tea reduces the risk of developing breast cancer, and may help reduce the risk of recurrence in breast cancer survivors (Seely D et al 2005).
Folic Acid. The use of folic acid dietary supplements, or the adoption of diets rich in fruits and vegetables containing folate, is associated with a reduced risk of developing cancer, particularly colorectal (Martinez ME et al 2004; Strohle A et al 2005) and lung cancers (Shen H et al 2003). Sufficient intake of folic acid is also thought to protect against breast cancer (Zhang SM 2004) because folic acid guards against DNA damage and promotes gene stability (Strohle A et al 2005).
Melatonin. The hormone melatonin, produced by the pineal gland during night-time hours, has anti-cancer properties (Anisimov VN 2003; Sainz RM et al 2005).
Selenium supplements have cancer-preventive properties (Combs GF, Jr. 2005), particularly in reducing the occurrence of lung, colorectal, esophageal, and prostate cancers (Mark SD et al 2000).
Silymarin, a milk thistle extract, demonstrates anti-cancer properties against prostate cancer cells and may be useful in preventing and treating prostate cancer (Singh RP et al 2004; vis-Searles PR et al 2005).
Vitamin A derivatives, known as retinoids, protect against the development of various cancers, including those of the skin, breast, and lung (Clarke N et al 2004; Khera P et al 2005). Dietary supplementation with synthetic vitamin A for 12 months in liver cancer survivors prevented recurrence of this cancer (Takai K et al 2005). In addition to preventing cancer, vitamin A derivatives have been used to cure acute promyelocytic leukemia (Clarke N et al 2004).
Vitamin C. Long-term human studies have shown that vitamin C dietary supplements, when used in conjunction with other antioxidants, can reduce the risk of developing cancer (Hercberg S et al 2004). Similar results were found for cancers of the prostate (Meyer F et al 2005) and lung (Mooney LA et al 2005; Wright ME et al 2004).
Vitamin D. Moderate sun exposure causes the synthesis of vitamin D in the skin. This micronutrient is known to play a role in cancer prevention (Holick MF 2004; Kimlin MG et al 2004). Indeed, medical literature dating back more than 50 years affirms that regular sun exposure is associated with a substantial decrease in death rates from certain types of cancers (Ainsleigh HG 1993). It is estimated that moderate sun exposure without sunscreen—that is, enough to stimulate vitamin D production but not enough to damage the skin—could prevent 30,000 cancer deaths in the United States each year (Ainsleigh HG 1993). The sun’s most damaging rays occur between 10 a.m. and 3 p.m., the hours demanding the greatest watchfulness.
Vitamin E. Clinical studies have shown that vitamin E can reduce the risk of prostate and lung cancers, particularly when used in combination with selenium supplements (Helzlsouer KJ et al 2000; Woodson K et al 1999). Regular and long-term (over 10 years) use of vitamin E reduces the risk of death from bladder cancer (Jacobs EJ et al 2002). Similarly, the use of vitamin E supplements for longer than three years slightly reduces the risk of recurrence among breast cancer survivors (Fleischauer AT et al 2003).
Vitamin K has been shown in laboratory and animal studies to have anti-cancer properties (Lamson DW et al 2003). Results from a small clinical study indicate that vitamin K may protect women with viral liver cirrhosis, a known risk factor for liver cancer, from developing the disease (Habu D et al 2004).
adapted from Life Extension articles
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