Cancer And Weight Gain
We hear it all the time...lose weight for your health. Few
people however, realize the extent to which this is critical to
their physical well-being and ultimately their life expectancy.
In January 2003, the Journal of the American Medical Association
featured a study finding that obesity appears to lessen life
expectancy, especially among young adults. The researchers
compared Body-Mass Index (BMI) to longevity and found a
correlation between premature death and higher BMIs. For
example, a 20-year-old white male, 5'10" weighing 288 pounds
with a BMI of greater than 40 was estimated to lose 13 years of
his life as a result of obesity.
Jamie McManus, M.D., F.A.A.F.P. and author of "Your Personal
Guide to Wellness" notes that while this study referenced
extreme levels of obesity, there are still millions of
overweight people in developed countries with a life expectancy
rate that is three to five years less than their healthy-weight
counterparts. Australia is following the US trends where an
alarming 600,000 obesity related deaths occur each year.
Just how does obesity shorten our lifespan? The answer to this
question is complex, yet there is a clear link between obesity
and the development of cancer. An extensive study conducted by
the American Cancer Institute involving 750,000 people showed
that obesity significantly increased the risk of cancer
developing in the following organs: breast, colon, ovaries,
uterus, pancreas, kidneys and gallbladder.
Michael Thun, MD, vice-president of epidemiology and
surveillance research for the American Cancer Society (ACS) says
one reason obesity may raise cancer risk is because fat cells
produce a form of estrogen called estradiol that promotes rapid
division of cells, increasing chances of a random genetic error
while cells are replicating, which can lead to cancer. In
addition, fat centered around the abdomen may increase insulin
and insulin-like growth factors in the blood, which may increase
cancer risk. "Women who are obese after menopause have a 50%
higher relative risk of breast cancer," notes Thun, "and obese
men have a 40% higher relative risk of colon cancer....
Gallbladder and endometrial cancer risks are five times higher
for obese individuals".
There is evidence that cancer rates in developed countries are
increasing at 5 to 15 times faster than developing countries. A
major contributor to this alarming reality has proven to be
diet. In populations where the diet consists mostly of fresh
fruit and vegetables and whole grains - in contrast to the
typical Western diet of fatty meats, refined flours, oils and
sugars - the risk of cancer is much lower.
The interaction of diet and the development of cancer is an
active field of research and Dr David Heber, M.D., Ph.D. and
author of "What Color is Your Diet", says "It appears that diet
has its most significant effects after the cancer has already
formed, acting to inhibit or stimulate the growth of that
cancer". At the risk of oversimplifying a complex set of
interactions, the typical Western diet that leads to obesity may
actually act to stimulate the growth of cancer cells.
It is never too late to improve your health through healthful
eating and adopting a more health-giving lifestyle.