Complementary Alternative Cancer Therapies

Natural Strategies for Boosting Resistance to Cancer

Prevention of Cancer Development and Progression

Natural strategies known to prevent the development and progression of cancer include:

• Calcium
• Carotenoids
• Curcumin
• Garlic
• Green and black teas
• Folic acid
• Melatonin
• Selenium
• Silymarin
• Vitamin A
• Vitamin C
• Vitamin D
• Vitamin E
• Vitamin K.

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).

According to the American Journal of Clinical Nutrition, individuals seeking broad spectrum colon protection should also include foods rich in lutein (another type of carotenoid) in their diet (Slattery ML et al 2000). These include spinach, broccoli, lettuce, tomatoes, oranges, carrots, celery, and greens.

Curcumin, extracted from the spice turmeric, 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).

In a phase I clinical study of colorectal cancer patients, curcumin in doses of up to 3.6 grams a day improved some clinical markers and was not associated with any toxicities (Sharma RA et al 2004). Clinical studies have shown that curcumin in doses of up to 10 grams a day had no adverse effects in humans (Aggarwal BB et al 2003).

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).

Garlic consumption lowers the risk of developing a range of cancers, including those of the stomach, colon, mammary glands, cervix (Khanum F et al 2004; Sengupta A et al 2004), and prostate (Hsing AW et al 2002). Garlic-derived allitridum, taken in combination with selenium, protects against the development of gastric cancer (Li H et al 2004).

Various other garlic extracts, including aged garlic extract, allicin, and ajoene, have a range of cancer-preventive and therapeutic capabilities (Oommen S et al 2004; Tanaka S et al 2004; Xu B et al 2004).

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).

Consumption of green tea also significantly improves the survival of ovarian cancer patients (Zhang M et al 2004) and reduces the risk of developing cancers of the lung, breast, and prostate (Bonner MR et al 2005; Doss MX et al 2005).

Such is the strength of data demonstrating green tea’s potential in preventing cancer that Japanese researchers are trying to develop a strategy, based on green tea consumption, for delaying cancer onset in the Japanese population, as well as reducing the risk of recurrence in cancer survivors (Fujiki H 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).

The use of melatonin (20 mg a night) during chemotherapy improves survival and quality of life in lung cancer patients (Lissoni P et al 2003). Melatonin also reduces the growth potential of prostate and breast cancer cells (Sainz RM et al 2005; Shiu SY et al 2003).

Further evidence supporting melatonin’s role as a cancer-preventive agent comes from studies showing an elevated risk of breast cancer in night-shift workers and others who have lower levels of melatonin due to the disruption of their waking and sleeping cycles (Anisimov VN 2003). Interestingly, blind people, who generally have higher melatonin levels, have lower rates of cancer (Coleman MP et al 1992; Feychting M et al 1998).

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). Indeed, low selenium levels are associated with a four- to fivefold increase in the risk of developing prostate cancer (Brooks JD et al 2001). Higher selenium levels are associated with a reduced risk of prostate cancer (Brooks JD et al 2001). Because selenium levels decline with age, selenium supplements may be of particular benefit to elderly men (Brooks JD et al 2001).

However, the benefits of selenium supplements in preventing cancer appear to be cancer-specific, as some clinical studies have shown supplementation to be ineffective in protecting against basal and squamous cell carcinomas of the skin (Clark LC et al 1996). Indeed, selenium supplements may increase the risk of squamous cell carcinoma (Duffield-Lillico AJ et al 2003b).

In addition to their cancer-preventive potential, selenium supplements may enhance the effectiveness of conventional chemotherapy treatment (Vadgama JV et al 2000) and improve quality of life for patients undergoing radiation therapy (Hehr T et al 1997).

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.

Insufficient vitamin D levels are particularly associated with increased risk of developing breast, colon, and prostate cancers (Chen TC et al 2003; Studzinski GP et al 1995). Increased vitamin D levels, obtained through sun exposure, are associated with a reduced risk of non-Hodgkin’s lymphoma (Hughes AM et al 2004). Vitamin D causes bones to release calcium and can thus lead to excessively high calcium levels (hypercalcemia); however, scientists are developing synthetic versions of natural vitamin D (deltanoids) that lack this adverse side effect (Agoston ES et al 2006; Guyton KZ et al 2003).

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).

In addition, animal studies indicate that vitamin E may have activity against colon cancer and melanoma (Barnett KT et al 2002; Malafa MP et al 2002b; Malafa MP et al 2002a).

Larger clinical studies are currently underway to further assess vitamin E’s protective role against prostate cancer (Fleshner N et al 2005; Lippman SM et al 2005).

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).

Preventing Tumor Spread (Angiogenesis, Invasion, and Metastasis)

Natural strategies that arrest the spread of tumors include:

• Alpha tocopherol
• Curcumin
• Green tea
• Pomegranate extracts
• Soy (genistein).

Alpha-Tocopherol supplementation, which provides the biological activity of vitamin E, reduces levels of vascular endothelial growth factor (VEGF), a tumor growth factor that plays a critical role in the formation of new blood vessels by cancer cells and subsequent tumor invasion of other organs (Woodson K et al 2002). Indeed, levels of this cancer growth factor decreased by 11 percent in the supplemented group but increased by 10 percent in the non-supplemented group (Woodson K et al 2002).

Curcumin is known to arrest the growth of established cancer (Furness MS et al 2005) by interfering with the production of growth factors that cancer cells need to establish new blood vessels and thus invade other organs, a process known as angiogenesis (Arbiser JL et al 1998; Dulak J 2005; Furness MS et al 2005).

Green Tea. Epigallocatechin in green tea has long been known to have cancer-preventive properties (Cooper R et al 2005). Epigallocatechin prevents cancer cells from forming new blood vessels and thereby spreading to other organs (Jung YD et al 2001).

Pomegranate Extract. A laboratory study has demonstrated that extracts of the pomegranate fruit can prevent human prostate cancer cells from invading new tissues (Albrecht M et al 2004).

Soy (Genistein). Present in soy, genistein prevents any cancer cells that persist after surgery from invading new organs and spreading (Vantyghem SA et al 2005). This potential to arrest the spread of cancer is linked to genistein’s ability to reduce production of the growth factor VEGF, a prerequisite for cancer spread and invasion (Ravindranath MH et al 2004).

Enhancing the Immune System

A range of CAM therapies have been shown to boost immune function in cancer patients. These include:

• Fermented wheat germ
• Garlic
• Herbal medicines
• Mushroom extracts
• Immunonutrition
• Melatonin
• Probiotic bacteria
• Relaxation techniques
• Vitamin E.

Fermented Wheat Germ. Neutropenia, a condition characterized by low numbers of white blood cells known as neutrophils, is a complication of chemotherapy that leaves patients dangerously susceptible to infections (Mego M et al 2005). Supplementing with fermented wheat germ extract during conventional treatment reduces the occurrence of neutropenia (Garami M et al 2004).

Garlic supplementation boosts immune function in cancer patients (Patya M et al 2004) by improving the function of natural killer cells and lymphocytes (Hassan ZM et al 2003; Patya M et al 2004; Tang Z et al 1997).

Herbal Medicines such as echinacea, ginseng, and astragalus strengthen the immune system and may be beneficial to cancer patients (Block KI et al 2003; Suh SO et al 2002). Indeed, red ginseng boosts the immune system of gastric cancer patients undergoing chemotherapy after surgery (Suh SO et al 2002). Patients taking red ginseng had significantly higher overall survival (76 percent) than non-supplementing subjects (39 percent) at five years (Suh SO et al 2002).

Mushroom Extracts increase the activity of natural killer cells in gynecological cancer patients undergoing chemotherapy (Ahn WS et al 2004). A Ganoderma lucidum polysaccharide extract known as ganopoly (1800 mg, three times daily before meals for 12 weeks) boosted natural killer cell numbers in advanced-stage cancer patients (Gao Y et al 2003).

In a randomized, double-blind, placebo-controlled study of 68 patients with advanced (stage III or IV) non-small cell lung cancer, polysaccharide peptides (PSP) isolated from the mushroom Coriolus versicolor (340 mg, three times daily for four weeks) significantly improved blood leukocyte and neutrophil counts, serum IgG and IgM, and percentage of body fat compared to the control group (Tsang KW et al 2003).

In a case series of eight patients with various cancers (mostly stage II-IV), a combination of maitake mushroom (Grifola frondosa) MD-fraction and whole maitake powder resulted in a positive response in 23 of 36 cancer patients. Cancer regression or significant symptom improvement was observed in 69 percent of breast cancer patients, 63 percent of lung cancer patients, and 58 percent of liver cancer patients. The study found a less than 10 percent to 20 percent improvement in leukemia, stomach cancer, and brain cancer patients. In addition, when maitake was taken in addition to chemotherapy, immune-competent cell activities were enhanced 1.2 times to 1.4 times compared to chemotherapy alone (Kodama N et al 2002).

Immunonutrition. Patients who undergo surgery to remove a tumor mass often suffer depressed immune systems following surgery, which slows their recovery and leaves them vulnerable to infection (Ates E et al 2004). Different forms of nutrition designed to boost the immune system assist the recovery of cancer patients after surgery (Ates E et al 2004; Braga M et al 2002; Song JX et al 2002). For example, patients administered nutrients containing fatty acids (with the aid of a feeding tube directly into the stomach) have a more rapid recovery of immune cell numbers (Ates E et al 2004). Oral supplements enriched with arginine and omega-3 fatty acids improved immune recovery and reduced infection rates (Braga M et al 2002; Song JX et al 2002).

Melatonin is a hormone with immune regulatory activities. Most cancer patients have low levels of melatonin (Bartsch C et al 1999). Melatonin supplements (10 mg a day) improve immune function in patients suffering from a variety of cancers, including gastric, renal, prostate, and bladder cancers, without any apparent adverse effects (Neri B et al 1998). Clinical studies support melatonin’s value, demonstrating that supplements of 20 mg a day can improve immune function in cancer patients, predominantly by enhancing the immunity driven by the two chief anti-tumor messengers, interleukin-2 and interleukin-12 (Lissoni P 2000, 2002).

Probiotic Bacteria. When cancer patients with neutropenia (low neutrophil counts) exhibit symptoms of infection such as fever, the condition of neutropenia is referred to as febrile neutropenia (Mego M et al 2005). The movement of bacteria through the intestinal lining is partly responsible for febrile neutropenia (Mego M et al 2005). Interestingly, scientists have demonstrated that colonizing the intestine with friendly probiotic bacteria reduced (by virtue of competition) infection from febrile neutropenia-causing bacteria (Mego M et al 2005).

Relaxation Techniques. Perhaps not surprisingly, clinical studies have now shown that humor and laughter have a positive effect on the immune system, characterized by increased numbers of natural killer cells (Bennett MP et al 2003; Berk LS et al 2001; Christie W et al 2005; Takahashi K et al 2001).

Other techniques such as massage and meditation that are designed to foster relaxation also improve immune system function in cancer patients (Hernandez-Reif M et al 2004, 2005; Hidderley M et al 2004). In fact, breast cancer patients participating in a massage therapy program had increased numbers of natural killer cells and lymphocytes (Hernandez-Reif M et al 2004, 2005).

Vitamin E. Short-term supplementation with high-dose (750 mg) vitamin E increases both the number and activity of lymphocytes in patients with advanced colorectal cancer (Malmberg KJ et al 2002). In addition, supplementation with vitamin E during chemotherapy reduces the loss of white blood cells (neutropenia) that is associated with chemotherapy (Branda RF et al 2004).