It Pumps Oxygen into Your Tissues and Helps Chase Away Cancer
Exercise—an Important Component of
Cancer Treatment and Dementia Prevention
April 10, 2015
Story at-a-glance
Exercise can help slash your risk of cancer; help
cancer patients recuperate faster; and diminish your
risk of cancer recurrence. It also helps diminish
your risk of dementia
Being fit in middle age cut men’s risk of lung
cancer by 55 percent, and bowel cancer by 44
percent. It also reduced their risk of dying from
lung, bowel, and prostate cancer by nearly one-third
In seniors who are at high risk of dementia,
cognitive decline can be reduced with a
comprehensive program addressing diet, exercise,
brain training, and managing metabolic and vascular
risk factors
By Dr. Mercola
When you think of reducing your risk of devastating diseases
such as
dementia and cancer,
is exercise at the top of your list? If it isn’t, you may want
to reconsider.
Compelling evidence suggests
exercise can not only
help slash your risk of cancer, it also helps cancer patients
recuperate faster, and diminishes your risk of cancer
recurrence.
There’s also plenty of research demonstrating that exercise
benefits your brain as much as it does your body, and with rates
of dementia rising precipitously, this is another significant
reason to make sure you stay more active, regardless of your
age.
Middle-Age Fitness Cuts Men’s Cancer Risk
One of the
benefits of exercise is that it decreases your insulin
resistance, and this is a profoundly effective strategy to
reduce your cancer risk. This creates a low sugar environment
that discourages the growth and spread of cancer cells.
Exercise also improves circulation, driving more oxygen into
your tissues, and circulating immune cells in your blood.
Previous animal research1,2
suggests regular exercise may be the key to significantly reduce
your chances of developing liver cancer, which is among the most
common types of cancer.
More recently, research3,4
published in the journal JAMA Oncology found that being
fit in middle age cut men’s risk of being diagnosed with lung
cancer by 55 percent, and bowel cancer by 44 percent.
High levels of cardiorespiratory fitness (CRF) in middle age
also helped men survive cancer, reducing their risk of dying
from lung, bowel, and prostate cancer by nearly one-third (32
percent). Not surprisingly, it also reduced their risk of dying
from cardiovascular disease by 68 percent.
Other Studies Show 20-40 Percent Reduced Cancer Risk with
Regular Exercise
Earlier research has also found that exercise—in this case
weight training—cut men’s risk of dying from cancer by 40
percent. Similar findings have been reported in other studies.
According to a 2003 paper5
published in the journal Medicine & Science in Sports &
Exercise, "more than a hundred epidemiologic studies on the
role of physical activity and cancer prevention have been
published." The authors noted that:
"The data are clear in showing that physically active
men and women have about a 30-40 percent reduction in the
risk of developing colon cancer, compared with inactive
persons…
With regard to breast cancer, there is reasonably
clear evidence that physically active women have about a
20-30 percent reduction in risk, compared with inactive
women.
It also appears that 30-60 min·d-1 of moderate- to
vigorous-intensity physical activity is needed to decrease
the risk of breast cancer, and that there is likely a
dose-response relation."
Exercise Boosts Effectiveness of Breast Cancer Treatment
Another recent study6
reported in the New York Times7
found that aerobic exercise slowed the growth of breast cancer
tumors in mice. By increasing tissue oxygenation, it also
improved the effectiveness of chemotherapy. As noted in the
article:
“The results raise the possibility that exercise may
change the biology of some malignant tumors, potentially
making them easier to treat.”
In one part of the trial, mice with breast cancer were
divided into four groups. One group received no treatment and
remained sedentary; one group ran on wheels but received no drug
treatment; a third group received chemotherapy treatment while
remaining sedentary; and the fourth group received both
chemotherapy and exercise.
At the end of the trial, the sedentary mice had large,
hypoxic tumors. Hypoxia is a condition in which your body, or a
region of your body, is deprived of oxygen, which is known to
make tumors less responsive to chemotherapy.
The exercise- and chemotherapy-only groups both revealed a
slow-down in tumor growth, compared to the sedentary, untreated
mice. The group that fared the best, however, was those who
exercised in combination with chemotherapy treatment. As noted
in the article:
“That result suggests, Dr. Dewhirst says, that
exercise had made the breast cancer tumors in the mice more
amenable to the chemotherapy. By making the tumors less
hypoxic — and paradoxically healthier, he says — exercise
‘also had made those tumors easier to kill.’
At the same time, exercise seems to have fought the
tumors independently of the chemotherapy drugs. In the
animals that ran but did not receive chemotherapy, Dr.
Dewhirst says, the scientists found blood markers indicating
a high degree of tumor cell death...”
Exercise Needs to Be Part of the New Standard of Care for Cancer
Mounting research suggests that exercise is a really
important part of cancer care and prevention, and Macmillan
Cancer Support8
has made strong arguments for its inclusion in standard cancer
care. I personally believe it is negligent malpractice to not
seek to include it nearly everyone’s cancer plan.
The British organization recommends that all
patients getting cancer treatment should be told to engage in
moderate-intensity exercise for two and a half hours every
week, stating that the advice to rest and take it easy
after treatment is an outdated view.
Macmillan offers loads of helpful information about the
benefits of exercise for cancer patients on their website, and
also has a number of videos on the subject, available on their
YouTube channel.9
According to Ciaran Devane, chief executive of Macmillan Cancer
Support:10
"Cancer patients would be shocked if they knew just
how much of a benefit physical activity could have on their
recovery and long term health, in some cases reducing their
chances of having to go through the grueling ordeal of
treatment all over again..."
Indeed, the reduction in risk for recurrence is quite
impressive. For example, previous research has shown that breast
and colon cancer patients who exercise regularly have half
the recurrence rate than non-exercisers.11
Macmillan Cancer Support also notes that exercise can help you
to mitigate some of the common side effects of conventional
cancer treatment, including:
A Fit and Healthy Lifestyle Also Improves Cognitive Function in
Seniors
According to a recent randomized controlled trial,12,13
in seniors who are at high risk of dementia, cognitive decline
can be reduced with a comprehensive program addressing diet,
exercise, brain training, and managing metabolic and vascular
risk factors. A total of 1,260 adults in Finland, aged 60-77
years, participated in the Finnish Geriatric Intervention Study
to Prevent Cognitive Impairment and Disability. Half were
randomly assigned to the intervention group, while the other
half served as controls.
All participants were at high risk of dementia. The
intervention consisted of attending regular meetings over the
two-year trial period with various health professionals to
address diet, exercise, brain training exercises, and metabolic
risk factors. At the end of two years, the intervention group
scored 25 percent higher overall on the Neuropsychological Test
Battery (NTB)—a standard test to evaluate mental
functioning—than the control group. They scored even higher on
certain parts of the test.
“[F]or executive functioning (the brain's ability to
organize and regulate thought processes) scores were 83
percent higher in the intervention group, and processing
speed was 150 percent higher. According to Professor
Kivipelto, ‘Much previous research has shown that there are
links between cognitive decline in older people and factors
such as diet, heart health, and fitness. However, our study
is the first large randomized controlled trial to show that
an intensive program aimed at addressing these risk factors
might be able to prevent cognitive decline in elderly people
who are at risk of dementia.’"
Other Research Shows Exercise Boosts Brain Growth and
Regeneration
Scientists have been linking physical exercise to brain
health for many years. In fact, compelling evidence shows that
physical exercise helps build a brain that resists shrinkage and
increases cognitive abilities.15
For example, we now know that exercise promotes a process known
as neurogenesis, i.e. your brain’s ability to adapt and grow new
brain cells, regardless of your age. According to John J. Ratey,
a psychiatrist who wrote the book Spark: The Revolutionary
New Science of Exercise and the Brain, there’s overwhelming
evidence that exercise produces large cognitive gains and helps
fight dementia.
One of the mechanisms by which your brain benefits from
physical exercise is via a protein called Brain Derived
Neurotrophic Factor (BDNF). Exercise initially stimulates the
production of a protein called FNDC5, which in turn triggers the
production of BDNF. BDNF is a remarkable rejuvenator in several
respects. In your brain, BDNF not only preserves existing brain
cells,16
it also activates brain stem cells to convert into new neurons,
and effectively makes your brain grow.
Research17
confirming this includes a study by Kirk Erickson, PhD, in which
seniors aged 60 to 80 who walked 30 to 45 minutes, three days
per week for one year, increased the volume of their hippocampus
by two percent. The hippocampus is a region of your brain
important for memory. Erickson also found that higher fitness
levels were associated with a larger prefrontal cortex. He
called exercise as "one of the most promising nonpharmaceutical
treatments to improve brain health." Two additional mechanisms
by which exercise protects and boosts your brain health include
the following:
Reducing plaque formation: By altering
the way damaging proteins reside inside your brain, exercise
may help slow the development of Alzheimer's disease. In one
animal study,18
significantly fewer damaging plaques and fewer bits of
beta-amyloid peptides, associated with Alzheimer's, were
found in mice that exercised.
Decreasing BMP and boosting Noggin:
Bone-morphogenetic protein (BMP) slows down the creation of
new neurons, thereby reducing neurogenesis. If you have high
levels of BMP, your brain grows slower and less nimble.
Exercise reduces the impact of BMP, so that your adult stem
cells can continue performing their vital functions of
keeping your brain agile.
In an animal research,19,20
mice with access to running wheels reduced the BMP in their
brains by half in just one week. In addition, they also had
a notable increase in another brain protein called Noggin,
which acts as a BMP antagonist. So, exercise not only
reduces the detrimental effects of BMP, it simultaneously
boosts the more beneficial Noggin as well. This complex
interplay between BMP and Noggin appears to be yet another
powerful factor that helps ensure the proliferation and
youthfulness of your neurons.
Exercise—an Important Component of Cancer and Dementia
Prevention
There’s no denying that exercise can have a profound impact
on your health, and a major part of its benefit lies in its
ability to prevent disease. Dementia and cancer are but two in
an inordinately long list of health problems that can arise as a
result of
chronic inactivity. Your metabolic and cardiovascular health
is also largely dependent on exercise. In fact, one of the
primary benefits of exercise is that it improves your insulin
and leptin sensitivity, and insulin/leptin resistance is a
hallmark of most chronic diseases, including cancer.
Ideally, you’ll want to establish a
comprehensive exercise program that includes
high-intensity exercises and
strength training—both of which have been shown to be of
particular benefit for brain health and cancer prevention. I
also urge you to consider walking more, in addition to
your regular workout regimen. Ideally, aim for 7,000 to 10,000
steps per day. Also avoid sitting as much as possible—ideally
limiting your sitting to three hours a day or less. Naturally,
if you have cancer or any other chronic disease, you will need
to tailor your exercise routine to your individual
circumstances, taking into account your fitness level and
current health.
Often, you will be able to take part in a regular exercise
program -- one that involves a variety of exercises like
strength training, core-building, stretching, aerobic, and
anaerobic -- with very little changes necessary. However, at
times you may find you need to exercise at a lower intensity, or
for shorter durations. Always listen to your body and if you
feel you need a break, take time to rest. But even exercising
for just a few minutes a day is better than not exercising at
all, and you'll likely find that your stamina increases and
you're able to complete more challenging workouts.
If your immune system is severely compromised, you may want
to exercise at home instead of visiting a public gym. But
remember that exercise will ultimately help to boost your immune
system, so it's very important to continue with your program
even if you suffer from chronic illness or cancer.