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http://tinyurl.com/kc2tk was a convenient entry into this
message.
Examining the figure in a perspective, it was noted that the
absolute risk
of dying from obesity was even greater at greater ages,
whereas the relative
risk was lower in some body mass index categories, in the below
paper and the reports to which it refers.

Focus on Research: Overweight and Mortality among Baby
Boomers - Now We're
Getting Personal

T. Byers

New Engl J Med 355:758-760 2006.

"I am a baby boomer, and my body-mass index (BMI) is 27.3. I
am also an
epidemiologist, so for both personal and professional
reasons, I have
closely followed the sometimes divergent conclusions about
the health risks
associated with growing older and being a little overweight.
As reported in
this issue of the Journal, trials involving more than half a
million
Americans (Adams et al., pages 763-778) and more than a
million Koreans (Jee
et al., pages 779-787) are the latest in a series of cohort
studies
published in recent years on the risks associated with
excess adiposity. Now
that studies are beginning to describe the risk of death
associated with
even modest levels of adiposity among baby boomers, this
issue is getting
more personal for me.

At first glance, the new study involving members of
the AARP (formerly
the American Association of Retired Persons) looks
reassuring for those of
us who are not obese, but only overweight. Among the entire
cohort of AARP
members, the risk of death seems to be substantially
increased only for
those whose BMI is over 30, the cutoff defining obesity.
However, we have
learned in recent years that only studies of the
relationship between
adiposity and the risk of death that properly account for
tobacco use and
chronic medical conditions can be truly informative about
the risk caused by
lesser degrees of adiposity. The AARP study clearly shows
that if the
effects of smoking are set aside, at age 50, when the
prevalence of chronic
disease is low, there is also an elevated risk of death for
persons whose
BMIs are well below 30.

The study of adiposity and mortality among Korean
adults also shows a
graded relationship between BMI and death from atherosclerotic
cardiovascular disease across a very wide range of BMI
levels, including
what would be regarded as only modest levels of adiposity in
the United
States. This finding is a sobering reminder that because
obesity is now a
worldwide problem, the phenomenon of "global fattening" will
contribute to a
pandemic of chronic diseases for many years to come.

What are we to do about the epidemic of adiposity,
both collectively
and personally? As health care providers, we are all touched
by the personal
dimensions of the problem, sometimes because we are
ourselves overweight and
sometimes because of the many personal issues that arise as
we try to help
our patients. The medical management of hypertension,
hyperlipidemia, and
insulin resistance certainly helps, but the treatment of
these mediating
factors does not completely eliminate the excess risk
associated with
adiposity. Adverse consequences of adiposity are seen in
even quite
health-conscious cohorts, such as AARP members, insured
Korean patients,
American Cancer Society volunteers, and registered
nurses.1,2 Our inability
to negate these health risks may be due to the
irreversibility of some of
the biologic harm, our inability to achieve perfect control
over the known
mediating factors, or the effects of other
as-yet-uncontrollable factors,
such as the chronic inflammatory state of adiposity, as is
signaled by the
association between white-cell counts and BMI in the Korean
cohort study.

We baby boomers are now into the second half of our
lives. How will our
current excess weight, much of it gained after age 50 during
the ongoing
obesity epidemic, affect our health risks as we age? A 1999
study conducted
in an American Cancer Society cohort of more than a million
Americans1
provides a clear answer: among nonsmokers without chronic
medical
conditions, the risk of death is elevated even among the
modestly
overweight, and this elevated risk persists as age advances
(see graph).
Observations that the risk of death expressed as a ratio
(including the
relative risk in the AARP cohort and the hazard ratio in the
Korean cohort)
diminishes with advancing age cannot be taken as evidence
that the effects
of adiposity diminish. In fact, the absolute degree of
additional risk
associated with excess adiposity (the difference in risk
between overweight
persons and those of normal weight) substantially increases
with advancing
age, according to the analysis of the American Cancer
Society cohort. Risk
ratios diminish with advancing age simply because the ratios
are diluted by
the many other causes of death associated with aging, which
figure into both
the numerator and the denominator of the ratio.

Fig. Risk of Death Associated with BMI among Male
Nonsmokers without
Chronic Health Conditions, According to Age.

The annual risk of death is expressed as both the
relative risk (Panel
A) and the absolute amount of additional risk (risk
difference) (Panel B)
per 100,000 population, as reported in the American Cancer
Society Cancer
Prevention Study 2.1 Even though the excess risk of death
due to adiposity
increased with age, the relative risk decreased with age
because of dilution
by the many other causes of death associated with increasing
age.

As we baby boomers move past 50, we will have to
address the reality
that excess adiposity substantially increases with advancing
age.
Fortunately, evidence points to a substantial health benefit
from even small
changes in weight trajectory, so the achievement of an ideal
body weight
need not be the primary goal. There are many ways that
physicians can help
patients to make the critical first step of stopping weight
gain.3 Small
steps toward weight control, such as short bursts of
activity and discrete
changes in eating habits, need not require major lifestyle
modification.


In my own personal adiposity epidemic, small steps
seem to help. When I
turned 50, I began to gain weight, even though it seemed
that my eating and
activity habits had not changed. When I turned 55, I cut out
powdered
doughnuts and began to walk more. Now, at age 57, I am 10
pounds lighter, my
wife is happier that there is less powdered sugar on the
seat of the car,
and I have a little more energy. As I reflect on my BMI of
27.3, however, I
am now looking for more small steps. My office is located on
the fourth
floor of a building with both stairs and an elevator. Hmmm."