Research findings presented at the American Association for Cancer Research meeting, held this year in San Diego, suggest that supplementing with vitamin D and calcium may reduce colon cancer risk, while consuming too much iron might increase it.
Veronika Fedirko of Emory University presented her team’s discovery that supplementing colorectal adenoma (polyp) patients with 2 grams calcium, 800 international units of vitamin D, or a combination of the two for six months was associated with an increase of Bax, a protein that controls apoptosis (programmed cell death), compared with placebo group levels. By increasing Bax levels in the colon’s mucosa, a greater number of precancerous cells (such as those that are found in polyps) may self-destruct. The trial found that the greatest increase in the ratio of Bax to Bcl-2 (an apoptosis inhibitor) occurred in the group that received both calcium and vitamin D.
"We were pleased that the effects of calcium and vitamin D were visible enough in this small study to be significant and reportable," Dr Fedirko stated. "We will have to fully evaluate each marker's strength as we accumulate more data."
In another study presented at the AACR meeting, Emory University Rollins School of Public Health professor of epidemiology Robert Bostick, MD, MPH and colleagues found that individuals who consume high amounts of vitamin D and calcium had increased expression of E-cadherin, a calcium-dependent glycoprotein that moderates the movement and proliferation of colon cells. Loss of E-cadherin expression has been associated with the progression of cancer. The study involved the comparison of biopsy samples from individuals with and without sporadic colorectal adenoma, and is part of a larger effort to identify biomarkers for the development of colon cancer. "We want to have the equivalent of measuring cholesterol or high blood pressure, but for colon cancer instead of heart disease," Dr Bostick remarked. "These measurements will describe the climate of risk in the colon rather than spotting individual tumors or cells that may become tumors."
An additional abstract coauthored by Dr Bostick reported the finding in the same study population that high levels of iron are associated with a reduction in a protein known as APC needed to control cell growth. “Clinical implications of these findings, if confirmed, could include lowering iron intakes in adenoma patients to prevent adenoma recurrence or colorectal cancer,” the authors conclude.
The current studies contribute more evidence for a protective role for calcium and vitamin D in colorectal cancer. Dr Bostick’s team is involved in a ten year study at several centers which will evaluate the effects of increased calcium and vitamin D as well as biomarker-guided treatment on the recurrence of colon cancer.
Interventions that can prevent the development of colorectal cancer include screening for adenomas, removal of polyps by endoscopic polypectomy, excision of the large bowel (in FAP) (Munkholm P 2003; Watson P et al 1998), and regular NSAID use (Reeves MJ et al 1996; Giardiello FM et al 1993), in addition to the following dietary interventions:
Fiber from bran and cellulose is effective in reducing the risk of colorectal cancer development (Gonzalez CA 2006b); Greenwald P et al 1986). In those with low intake of dietary fiber, doubling of total fiber intake could reduce the risk of colorectal cancer by 40 percent (Bingham S 2006). Fruit fiber consumption, as opposed to vegetable fiber, reduces the risk of colorectal adenomas (Platz EA et al 1997). High-fiber foods include legumes, beans, seeds, nuts, wild rice, and oatmeal.
Calcium reduces the growth rate of rectal and colon epithelial cells both directly and by binding bile acids and fatty acids in the stool, resulting in compounds that are less likely to adversely affect the colon (Rozen P et al 1989). Calcium’s beneficial effects may occur only in individuals who have a low level of fat intake (Cats A et al 1995). Oral calcium supplementation reduces benign tumor (adenoma) formation by 19 percent (Baron JA et al 1999) and slightly reduces cell proliferation in the rectum (Cats A et al 1995). Foods such as broccoli, kale, Chinese cabbage, milk, cheese, and yogurt are good sources of calcium.
Curcumin is currently being investigated in human clinical trials for the prevention and treatment of colorectal cancer (Jiao Y et al. 2006a). Curcumin may be effective in preventing the development of colon cancer related to APC mutations (Corpet DE et al 2003; Pierre F 2003; Reddy BS et al 1994, 2002). The suggested daily dose is 1.6 grams (Perkins S et al 2002). Curcumin is extracted from turmeric root and is used as a spice in cooking.
Multivitamin use reduces the risk of benign tumor (adenoma) formation in high-risk individuals (Whelan RL et al 1999). Vitamins C, E, and A reduce the risk of developing colorectal cancer (Howe GR et al 1992; Newberne PM et al 1990).
The second Life Extension Seminar at Sea will be a 7-night cruise on August 29, 2008. This time we will cruise the splendor of the Alaskan wilderness aboard Celebrity’s sumptuous Infinity. You’ll enjoy our Life Extension seminars, one-on-one consultations, a welcome aboard cocktail reception, exceptional personal service, award-winning cuisine, world-famous amenities, accommodations that are the most spacious at sea, and much more.
Experience the extraordinary: Celebrity
Travel press, such as Condé Nast Traveler, consistently rate Celebrity Cruises as one of the world's finest cruise lines. Celebrity offers an incomparable cruise experience aboard ships of uncompromising style and sophistication. From spectacular dining to indulgent spa treatments, you’ll find countless possibilities to satisfy body and soul. Sleep upon Egyptian cotton linens, enjoy butler service in all suites, or special amenities with Concierge Class staterooms, dine in award-winning restaurants, pay a visit to Fortunes Casino, experience Las Vegas-style shows or a movie in the cinema, be pampered by Celebrity's exclusive AquaSpa programs, and much more.
A Celebrity Alaska cruise represents a thoroughly researched and carefully orchestrated collection of spectacular ports of call and exciting shore and land excursions, all connected by routes through some of the area’s most stunning land marine environments. Your ports of call: Seattle, Washington; Sitka, Alaska; Hubbard Glacier (Cruising); Juneau, Alaska; Ketchikan, Alaska; Victoria, British Columbia; Seattle, Washington.
It is a myth that shampooing increases hair loss; gentle washing even on a daily basis will not damage the hair or lead to hair loss. Hair type, level of physical activity, and even a person's occupation, should determine the frequency of shampooing.
The quality and health of your hair is partly reflected in having a well-balanced diet containing protein, amino acids, and vitamins. Iron deficiency, due to a lack of meat products in the diet or heavy menstrual bleeding in women, could affect the health of the hair.
Life Extension Shampoo is a deep-cleansing shampoo, yet a gentle formula perfect for everyday use.
As type 2 diabetes, metabolic syndrome, and pre-diabetes reach epidemic levels in the U.S., patients and physicians alike desperately need an innovative new strategy for prevention and treatment. In an eye-opening new book, Life Extension’s medical director Dr. Steven Joyal reveals a groundbreaking, integrative program that links the core causes of metabolic disease to accelerated aging. Dr. Joyal’s innovative plan integrates cutting-edge discoveries in an easy-to-follow fashion. What Your Doctor May Not Tell You About Diabetes offers a groundbreaking new program to dramatically enhance metabolic health in patients with diabetes as well as aging people interested in controlling key metabolic factors linked to accelerated aging.