Life Extension Magazine April 2004
Exercise May Help Prevent Breast Cancer
|LE Magazine April 2004|
|Exercise May Help Prevent Breast Cancer|
Regular exercise, even when begun later in life, can reduce a woman’s chance of developing breast cancer by approximately 20%, according to a study published in the Journal of the American Medical Association.
Researchers followed nearly 75,000 women aged 50 to 79 as part of the Women’s Health Initiative Cohort Study. The women were questioned about their current and past levels of physical activity, and this information was compared to their reported development of breast cancer. The study found that women who engaged in the equivalent of 1.25 to 2.5 hours per week of brisk walking had an 18% lower risk of breast cancer compared with inactive women during the nearly five-year study period. Women who engaged in 10 or more hours per week of brisk walking had a slightly greater reduction in risk. This reduction in breast cancer risk was evident even in women considered to be at higher risk for the disease, such as those with a strong family history of the disease and those who take hormone replacement therapy.
Lead researcher Anne McTiernan, MD, PhD, of the Fred Hutchinson Cancer Research Center in Seattle, WA, noted: “The good news is that even though hormone replacement therapy increases the risk of breast cancer, exercise is something women can do to lower this risk if they choose to continue taking hormone replacement therapy to manage the symptoms of menopause or to prevent osteoporosis.”
—Marc Ellman, MD
McTiernan A, Kooperberg C, White E, et al. Women’s Health Initiative Cohort Study. Recreational physical activity and the risk of breast cancer in postmenopausal women: the Women’s Health Initiative Cohort Study. JAMA. 2003 Sep 10;290(10):1331-6.
|Selenium Concentration Tied to Esophageal, Stomach Cancer Risk|
Higher serum concentrations of the mineral selenium are related to a lower incidence of esophageal squamous cell carcinoma and gastric cardia (upper stomach) cancer, according to the results of a study recently published in the American Journal of Clinical Nutrition.*
Chinese and US researchers studied 1,103 subjects who were selected from the Nutrition Intervention Trial of Linxian, China, which enrolled 29,584 adults aged 40 to 69. Serum selenium levels were measured at the study’s onset and participants were followed for next 15 years.
During the follow-up period, 516 deaths were recorded, including 116 from heart disease, 167 from stroke, 75 from esophageal squamous cell carcinoma, and 36 from gastric cardia cancer. Advanced age, male gender, low body mass index, and cigarette smoking emerged as factors that were more likely to be found in those who died compared to survivors. Significant associations were observed between higher serum selenium levels at the start of the study and a lower risk of death from esophageal squamous cell carcinoma and gastric cardia cancer. Subjects whose selenium concentrations were in the top 25% had a 69% reduction in gastric cardia cancer mortality risk compared to those whose selenium concentrations were in the bottom 25%. Those whose selenium concentrations were in the top 25% had a 65% lower risk of dying from esophageal squamous cell carcinoma compared to those with selenium concentrations in bottom 25%. Researchers found a similar but smaller association between higher selenium levels and lower incidence of heart disease, but found no trends associating selenium levels with stroke or total deaths, respectively.
Wei WQ, Abnet CC, Qiao YL, et al. Prospective study of serum selenium concentrations and esophageal and gastric cardia cancer, heart dis- ease, stroke, and total death. Am J Clin Nutr. 2004 Jan;79(1):80-5.
|Folate Deficiency Causes Radiation-Like Damage to DNA|
A deficiency in the B vitamin folate is more damaging than ionizing radiation in its effect on DNA strand breaks, according to a report published online by the Federation of the American Societies for Experimental Biology.*
DNA damage can lead to chromosomal aberrations and cancer. Folate and other vitamin and mineral deficiencies can cause DNA double-strand breaks, which are the most serious DNA lesion caused by ionizing radiation. Researchers irradiated human lymphocytes (white blood cells) at several doses, and cultured other lymphocytes in low concentrations of folate for 10 days. They found that folate deficiency and high doses of ionizing radiation caused DNA breaks and apoptosis. Ionizing radiation and folate deficiency also caused changes in cell cycle and gene expression. While radiation activated DNA double-strand break repair genes, folate deficiency was not found to do the same.
The authors concluded that folate deficiency may be more detrimental than low doses of radiation and noted that insufficient dietary folate causes sperm damage. Because most individuals’ exposure to radiation is relatively low, radiation may pose a smaller cancer risk than that incurred by a poor diet. According to the researchers: “Our results suggest that research on the biological effects of low-dose radiation, in humans, should take into account the nutritional status of the subjects, because folate (and other vitamin and mineral) deficiency could confound the effects of low-dose radiation or could even have a synergistic effect and increase the sensitivity of cells to radiation.”
Courtemanche C, Huang AC, Elson-Schwab I, Kerry N, Ng BY, Ames BN. Folate deficiency and ionizing radiation cause DNA breaks in primary human lymphocytes: a comparison. FASEB J. 2004 Jan; 18(1):209-11.
|Folate Use Linked with Reduced Stroke Risk in Men|
Vitamin B12 intake was associated with a lower risk of ischemic stroke and consumption of folate was significantly associated with lower risk, according to the results of a recent study published in the American Heart Association journal Stroke.*
In seeking to determine the role of folate and vitamins B6 and B12 in stroke prevention, researchers studied 43,732 men between the ages of 40 and 75 who were enrolled in the Health Professionals Follow-Up Study. Dietary information was obtained through the use of food frequency questionnaires administered at the study’s onset and twice during the follow-up period ending in 2000.
The study found 455 ischemic strokes, 125 hemorrhagic strokes, and 145 strokes of unknown origin were recorded during the follow-up period. Analysis of dietary data associated vitamin B12 and folate intake with a lower risk of ischemic stroke. Men in the top one-fifth of folate intake had a 30% lower stroke risk than those in the lowest fifth. Multivariate analyses of the data confirmed that the benefit of folate was not explained by overall healthier lifestyles in those whose folate intake was high. Because vitamin supplements were the major source of folic acid, however, other components of supplement formulas could be responsible for the benefits observed.
The protective benefit of folate and vitamin B12 against stroke could be due to their association with blood homocysteine, which may damage the blood vessels by accumulating in the endothelial cells and generating free radicals. Earlier studies have determined that elevated plasma homocysteine is a risk factor for ischemic stroke. While vitamin B6 levels also have been correlated with homocysteine levels, the association is less strong than correlations between homocysteine and folate and between homocysteine and vitamin B12, respectively.
He K, Merchant A, Rimm EB, et al. Folate, vitamin B6, and B12 intakes in relation to risk of stroke among men. Stroke. 2004 Jan;35(1):169-74. Epub 2003 Dec 11.
|International Conference to Spotlight Anti-Aging Breakthroughs|
In just three years, the International Anti-Aging Conference (formerly the Monte Carlo Anti-Aging Conference) has established itself as one of the world’s premier learning conferences for health professionals and life extensionists who are dedicated to using cutting-edge science to improve longevity, attain optimal health, and prevent and treat age-related diseases and disorders.
The International Anti-Aging Conference attracts hundreds of physicians, scientists, organizations, and life extension enthusiasts from around the world. The most recent conference drew participants from 26 countries. The conference presents renowned speakers sharing the latest breakthroughs in anti-aging and life extension science, from nutrition and orthomolecular medicine to hormone replacement therapy and biotechnology. In addition to meeting and networking with speakers and other participants, attendees have the opportunity to interact with exhibitors displaying cutting-edge protocols and products of interest to both the anti-aging health professional and enthusiast.
Phil Micans, vice president of International Anti-aging Systems and chairman of the three previous conferences, notes that “while other conferences are geared to those who are new to anti-aging medicine, the International Anti-Aging Conference appeals to those who are active and involved, and has thus been able to demonstrate the latest anti-aging developments as well as forecast imminent breakthroughs. This conference aims to keep people who are practicing and interested in anti-aging medicine on the cutting edge.”
For more information about the 2004 Anti-Aging Conference, to be held September 2-4 in London, England, please contact the organizers directly by phone, fax, or email: