Once a woman reaches her mid-20s, she immediately catches cancer's attention. Breast cancer particularly prays on slower easier targets, especially those women with more meat on their bones.
-Christine Horner, MD
Christine Horner, MD, a board-certified surgeon and author of Waking the Warrior Goddess, reminds us that breast cancer is a killer beast. This disease doesn't care about race, religious beliefs or social economic status. As Dr. Horner expressed, once a woman reaches her mid-20s, she immediately catches cancer's attention.1
Dr. Horner also notes that breast cancer tends to develop in slower, easier targets, especially those women who are obese, overweight and/or older and inactive.2 Henry S. Lodge, MD, a professor at Columbia Medical School and author of Younger Next Year, states that when we don't exercise, our muscles let out a steady trickle of chemicals that tell every cell to decay, day after day.3
Exercise acts as the master switch that instructs the cells to grow, recharge, detoxify and maintain homeostasis. The more the body receives signals from positive chemical messages induced by exercise, the more this message of "recharge" and "renew" is transmitted at the cellular level. Exercise makes cells stronger and keeps them youthful and better able to defend themselves.3
Breast cancer researchers now know that excess fat cells pose a definitive breast cancer risk. These fat cells accelerate the production of estrogen and insulin, which can increase cancer cell production.4
Although breast cancer can strike any woman, knowing how to counter its negative force is key to stopping an enemy intent on causing destruction.3 To that end, new research has revealed that exercise is cancer's most powerful adversary. Medical and health officials are encouraging women to run, walk, jog and to participate in aerobics, yoga and strength training classes. Such exercise awakens many dormant hormones, immune fighting chemicals and surveillance systems to beat breast cancer at its own game.5
This new approach is the result of recent pioneering studies conducted by Michelle Holmes, MD, at Boston's Brigham and Women's
Hospital. Dr. Holmes and colleagues reported that women with breast cancer who walk three or more hours a week (or exercise more strenuously for shorter periods) have a lower risk of dying from breast cancer than those who exercise less.5
October is Breast Cancer Awareness Month.
Don't miss these upcoming features in Healthy Aging's Patient Resource Center:
- Hear survivors' stories in an audio slideshow.
- Learn about early detection techniques.
- Read about life after breast reconstruction.
And visit ADVANCE's Healthcare Shop to purchase Breast Cancer Awareness merchandise.
In the past, doctors focused on the importance of women resting, rather than moving. New studies, however, show that women who have breast cancer can increase their survival rate by 20 percent to 50 percent based on the duration of their exercise routine.5
In a study of 2,900 female registered nurses who were diagnosed with stage I to III breast cancer, women who engaged in 3 to 8.9 metabolic equivalent task (MET) hours of activity per week reduced their risk of death by 20 percent. When activity levels rose to 9 to 14.9 MET hours of activity per week, women reduced their risk of death by 50 percent. Rates of physical activity of 15 to 23.9 and up to 24 MET hours resulted in death rate reductions of 44 percent and 40 percent, respectively. This study, which was conducted from 1984 through 2002, revealed that 92 percent of the women who were still alive had exercised at least three to fives times a week.5
Another fascinating study appeared in the February 2008 edition of Cancer Epidemiology Biomarkers and Prevention. Researchers examined the relationship between physical activity after breast cancer diagnosis and survival of women ages 20 to 79. Physical activity was based on MET hours per week. Data collected from this study indicated that women who engaged in 21 MET hours of physical activity a day vs. those engaged in 2.8 MET hours of physical activity a day had a significantly lower risk of dying from the disease. Similar results were seen in all age groups, regardless of disease stage and body mass index.
Investigators at the Fred Hutchinson Cancer Research Center in Seattle concluded that women who actively participated in moderate physical activity after a breast cancer diagnosis reduced their overall mortality and mortality.6
Improving Quality of Life
In addition to extending life and survival rates, physical activity also improves quality of life issues for women with breast cancer. Researchers at the University of Alberta in Edmonton, Canada, conducted a multicenter randomized controlled trial of 242 breast cancer patients. The study sought to evaluate the merits of aerobic and resistance exercise on body composition, psychosocial functioning and quality of life among women who were in chemotherapy treatments for 24 weeks.7
At the end of the study, investigators reported that aerobic exercise was superior for improving self-esteem and body fat percentages. They also found that resistance exercise significantly improved self-esteem, muscular strength and lean body mass. None of the women in the study showed signs of developing lymphedema.7
Researchers at the School of Human Movement and Exercise Science at the University of Western Australia conducted a randomized controlled trial to examine the effects of aerobic and resistance exercise on breast cancer survivors. In this study, 58 women were randomly assigned to either an immediate exercise group (29) and a delayed exercise group (29). The women in this study had survived breast cancer for two years and had recently completed adjuvant therapy.
The immediate group completed 12 weeks of supervised aerobic and resistance exercise three times per week. The delayed group completed the program over a 12-month time frame. Based on a functional assessment scale, the immediate exercise group showed an improvement of 20.8 points on the scale as compared to a decrease of 5.3 of the delayed group over a 12-week period.
At 24 weeks, quality of life issues (fatigue, social anxiety and physical fitness) improved in the immediate group by 29.5 points as compared to an improvement of 6.5 points in the delayed exercise group. The results of this study suggest that combined aerobic and resistance exercise after conventional breast cancer treatment produces large and rapid improvements in health-related outcomes.8
Researchers who conducted a 12-week collaborative study by four National Service Oncology clinics in Scotland reported that supervised exercise group programs provided functional and psychological benefits for cancer patients. The consensus among these institutions is that clinicians should encourage supervised physical activity for their cancer patients and should include exercise in cancer rehabilitation services.9
Identifying Early Biomarkers
Over the last several years, researchers have found that C-reactive protein is elevated in women who have breast cancer.10 Concurrent research of other cancers, such as colon, uterine and ovarian cancer, also have shown a link between elevated C-reactive protein and the development of cancer.11,12
Elevated levels of C-reactive protein are now reported as an independent risk factor in women and can cause heart disease and increased rates of mortality.13 All of the collective data indicate that exercise reduces the production of C-reactive protein and, in the process, can reduce the risk of breast cancer by 70 percent.14,15 Studies also show that exercise reduces the negative effects of radiation and chemotherapy, such as nausea and fatigue.16
Exercise Early in Life Reduces Cancer Risk
While many studies have focused on exercise's role in protecting postmenopausal women against breast cancer, scores of research have investigated its role in reducing the incidence of breast cancer in younger women.17 For example, researchers at the University of North Carolina examined the recreational and fitness habits of 1,264 women ages 20 to 54 who had been diagnosed with invasive breast cancer. The women who had participated in regular physical activity in the year leading up to their diagnosis had a much better chance of surviving breast cancer. In fact, those who did the most exercise and had a body mass index (BMI) of 25 or more during that period experienced survival rates that were 21 percent higher than those who did little or no exercise.18
The favorable results were more pronounced in the overweight or obese women. This may be a direct result of hormones being excreted from excess fat tissue. In fact, overwhelming evidence now shows that exercise greatly reduces estrogen levels in overweight women, increasing their chances of survival.18
Data collected from the Cancer Prevention Program at the Fred Hutchinson Cancer Research Center in Seattle followed 64,777 women participating in the Nurses Health Study II for six years. It showed that high levels of physical activity in women, ages 12 to 22 years, had the greatest long-term impact against cancer.19 Active women engaging in 39 or more MET hours per week of exercise over their lifetime had a 23 percent lower risk of developing breast cancer. The level of activity in this study equaled 3.25 hours a week of running or 13 hours a week of walking.19
Furthermore, researchers at the USC/Norris Comprehensive Cancer Center at the University of Southern California examined the relationship between breast cancer risk and age-specific measures of recreational exercise activity among white and black women, ages 35 to 64. The study reviewed detailed histories of 4,538 patients with newly diagnosed invasive breast cancer; 1,646 were black women and 3,033 were white women. An additional 4,649 controlled subjects were matched to case patients based on age and race.
The results showed that all women who increased their levels of lifetime physical activity equivalent to 15.2 MET hours a week reduced their risk of developing breast cancer by nearly 20 percent.20 Polish researchers reported similar findings and examined physical activity in four specific age groups of 250 women (14 to 20, 21 to 31, 35 to 50, and over 50). Lifetime total physical activity among all of the women in this study was linked with a reduction in breast cancer risk.21 However, these researchers found that women who started running or were engaged in recreational activity after age 20 had the highest risk of developing breast cancer than women who were active from age 14 to 20 and were inactive after age 20.21
In her research, Dr. Holmes found that women who benefited the most from exercise were those who were diagnosed with hormone-related cancers.5 Other studies have shown that women engaged in leisure-time or moderate- to vigorous activities reduced breast cancer risk, regardless of the underlying causes of the cancer's development.22
In addition, researchers at the University of Alberta and the Alberta Cancer Board in Canada compared more than 1,200 women who had recently been diagnosed with breast cancer with the same number of women who were cancer-free. In comparing lifestyles, researchers found that women who were active and exercised over a lifetime drastically reduced their risk of developing breast cancer, as opposed to those who didn't exercise.
Deepka Chopra, MD, the world-renowned expert on mind-body medicine, states that the force for healing lies somewhere within the patient.23 For all women-whether they're survivors, newly diagnosed with the disease or are genetically at risk for developing breast cancer-exercise is the key to remaining healthy for as long as possible. 24,25
Click Page 2 for a list of references.
George L. Redmon, PhD, ND, is a leading expert on nutritional supplements, herbal botanicals and holistic health care. He has authored six books on alternative ways to manage arthritis, chronic fatigue, sexual dysfunction, obesity and prostate disturbances.