Environmental
Drivers
of
Chronic Disease
Based on the report
Environmental Threats to
Healthy Aging
by
Jill Stein MD, Ted Schettler MD, MPH,
Maria Valenti and Ben Rohrer
2010
Greater Boston Physicians for Social Responsibility (www.psr.org/Boston)
and
The Science and Environmental Health Network (www.sehn.org)
What We Will Cover

Environmental factors are key drivers of many
common chronic diseases

Environmental factors alter key biological pathways
leading to chronic disease

Important environmental determinants of health
include:

-
Food system/nutrition and diet
-
Toxic chemicals
-
Built environment / physical activity
-
Psychological & socioeconomic stress
Examples of cross cutting solutions for healthy
people & a healthy environment
Scope & Context of the Problem
A
century of change in natural, built and social
environments has caused major changes in the
patterns and distribution of diseases.
 We
are seeing dramatic increases in chronic diseases,
and at younger ages, many of which, such as diabetes,
are themselves risk factors for dementia.
 The
over- 65 population will nearly double by 2030 to
more than 71 million, sharply increasing the number of
people at risk of chronic diseases of aging like
Alzheimer’s and Parkinson’s diseases, among others.
 Environmental
factors play a key role in health across
the lifespan. Thus they offer a major prevention
opportunity.
The Changing Environment and
Disease Patterns

During the past century, human activity has altered
virtually all aspects of the world’s ecosystems:
–
–
–
–

Pervasive spread of synthetic chemicals; air and water pollution.
Industrialized food supply.
Destruction of critical natural habitats, stressing ecosystems.
Climate change.
How we live, eat, work, play and socialize have
substantially changed:
–
–
–
Built environments have increased social
isolation for many people; reduced
physical activity.
Growing income gap increases disease risk.
Diseases of civilization - obesity, diabetes,
cardiovascular disease, hypertension.
Environment Drives Chronic Disease
Chronic
Disease
Environmental
Factors
Altered Pathways
•Food
system/Diet
•Fossil Fuels
•Socioeconomic Stress
•Chemicals
•Built Environment/
Transportation
•Inflammation
•Disrupted Insulin
Signaling
•Oxidative Stress
Parkinson’s
Western Disease Cluster
•Diabetes
•Obesity
•Abnormal Lipids
•Metabolic Syndrome
•Cardiovascular Disease
Alzheimer’s
Profound Public Health Impact
Of Environmentally-Driven Western
Disease Cluster

Obesity/overweight – 2/3 US adults, prevalence x2 in
~25 yrs http://www.cdc.gov/chronicdisease/resources/publications/AAG/obesity.htm

Pre/Diabetes – 40% US adults, prevalence DM ~x2
over 20 yrs Cowie 09, http://apps.nccd.cdc.gov/DDTSTRS/default.aspx

Cardiovascular disease – still leading cause of death.
Hypertension increasing. http://www.cdc.gov/nchs/FASTATS/lcod.htm, Hajjar 03

Metabolic syndrome = early signs of other cluster
diseases; 35% adults, ~55%>60 yrs Ford ES 05

Alzheimer’s disease – ½ >84 yrs old, 5.3M Alzheimer’s Assoc.
Alzheimer’s Disease/dementia

Not an inevitable feature of normal aging.

Progressive impairment of memory and multiple
other cognitive functions, severe enough to interfere
with daily functioning.

Expected to triple by mid-century
to over 13 million.

Likely caused by varying
combinations of genetic and
environmental factors.

Annual costs in US over $150 billion.
Parkinson’s Disease

Progressive movement disorder that includes tremors,
stiffness, and slow movement. May lead to severe
disability.

Likely caused by variable combinations of genetic and
environmental factors.

About 50,000 new cases
annually in US.*

Prevalence in US expected to
double by 2030.*
* Due to the lack of registries and baseline data on Parkinson’s Disease,
the figures used here are estimates.
Alzheimer’s and Parkinson’s
Diseases

Characterized by:
-

abnormal protein deposits
chronic inflammation
abnormal oxidative stress
Many neuroscientists are beginning to think
of some neurodegenerative diseases along a
continuum, without clearly distinct
boundaries in clinical or pathological
manifestations
Continuum of Age-Associated
Cognitive Impairment
Environment Drives Chronic Disease
Basic Principles

Early life experiences can influence later-life health
and disease.

Multiple factors interact to influence health & disease.

Environmental factors can alter natural pathways which
in turn can lead to chronic disease.

An ecological health framework considers the individual
in the context of family, community, society and
ecosystem.
Early life experiences can influence
later-life health, disease
Obesity, hypertension,
Cardiovascular disease,
diabetes
Toxic exposures
oxidative
stress
Low birth
weight
Aging begins at conception
Alzheimer’s,
dementia,
Parkinson’s
Multiple Factors Interact to Influence Health & Disease
nutrients
built
environment
disease
chemicals
energy
stress
An ecological health framework considers
the individual in the context of family,
community, society, and ecosystem.
Environment Drives Chronic Disease
Chronic
Disease
Environmental
Factors
Altered Pathways
Mechanisms of Action
Inflammation
Disrupted Insulin Signaling
Oxidative Stress
The New Concept of Inflammation
CLASSICAL CONCEPT
OF INFLAMMATION
Defined by microscopic
characteristics & laboratory test:
inflammatory cells & mediators
Defined by appearance.
“Calor, dolor, rubor, tumor.”
Heat, pain, redness, swelling.
“Atherosclerosis is an
inflammatory disease.”
(2) Ross, Russell. Atherosclerosis – An Inflammatory Disease. NEJM 1999, 340(2); 115-126.
Insulin Signaling =
Normal Metabolism
Insulin
signaling
•↓
blood sugar
•↓ artery disease
•↓ triglycerides
Disrupted Insulin Signaling =
Inflammatory Metabolism
Inflammation
Oxidative
stress
Insulin
signaling
• ↑ blood sugar
• ↑ artery disease
• ↑ triglycerides
Environment Drives Chronic Disease
Chronic
Disease
Environmental
Factors
Altered Pathways
Food System/Diet
Novel Nutrients Are Pervasive,
Promote Inflammatory Metabolism
mg/day
% of calories from fat
What’s “Novel” in the Western Diet?
Years
“Hypothetical scheme of fat, fatty acid (ω6, ω3, trans and total) intake (as percentage of calories from fat) and intake of vitamins E and C (mg/d). Data
were extrapolated from cross-sectional analyses of contemporary hunter-gatherer populations and from longitudinal observations and their putative
changes during the preceding 100 years [75].” From AP Simopoulos, The importance of the ratio of omega-6/omega-3 essential fatty acids.
Biomedicine & Pharmacotherapy 56 (2002) 365-379.
High Glycemic Carbohydrates
Increase the Risk of Chronic Disease
High glycemic carbohydrates break down quickly during digestion,
rapidly releasing glucose (sugar) into the bloodstream.
Δ Plasma Insulin,mg/dl
INSULINEMIC RESPONSE
Low glycemic food
High glycemic food
Time, mins
Properties of Fatty Acids
Omega-3
Omega-6
Saturated
Perishable
Short shelf life
Increased in
pasture- fed
animals
Durable
Processed foods
Long shelf life
Increased in
factory farmed
animals
Immune
Anti-inflammatory
Properties
Inflammatory &
Anti-inflammatory
Inflammatory
Evolutionary Recent marked
Recent marked
increase
Recent marked
increase
Food
System
Context
decline
Novel Nutrients Disrupt Insulin Signaling,
Drive Inflammatory Metabolism
↓Omega-3,
(↑Omega-6)
Saturated fat
Inflammation
Oxidative
stress
↓Antioxidants
Insulin
signaling
• ↑ blood sugar
• ↑ artery disease
• ↑ triglycerides
High Glycemic
Carbohydrates
Fructose
Influence of Nutrition
on Chronic Disease

Increase risks
-

saturated and trans fats
high glycemic carbohydrates
lack of fruits/vegetables/omega 3s
excess omega 6s?
Reduce risks
-
fruits, vegetables
omega 3s
low glycemic carbohydrates
Mediterranean diet
Benefits of Mediterranean-Type Diet
on Chronic Disease Risk
Clinical intervention studies
 70% ↓ heart attacks, cardiac death & total mortality
 60% ↓ cardiac events in CVD patients*
 ~50% ↓ metabolic syndrome
 39% ↓ in CRP
 ↓insulin resistance
 ↓ weight
DeLogeril 94
Ornish 98
Esposito 04
Esposito 04
Esposito 04
Esposito 04
Prospective observation studies
 80% ↓ diabetes
 ~31% ↓ all-cause & cardiovascular mortality, 22% ↓ cancer
mortality**
73% Alzheimer’s mortality
 25-30% ↓ Parkinson’s disease
 78% ↓ childhood asthma maternal diet
Martinez-Gonzalez 08
calculated from Sofi 08
Scarmeas 07
Gao 07
Chatzi 08
*10% low fat, vegetarian diet + exercise, stress reduction
**For every 2 point increase in adherence (on a 9 point scale), risk reductions were observed of 0.91 for all cause mortality, 0.91 for CV mortality, 0.94 for occurrence
and mortality from neoplasm. To convey the implications of these findings, we have applied the risk reductions across a 9 point adherence scale to yield a calculated
~31% ↓ all-cause & CV mortality and a 22% ↓ in cancer mortality.
Benefits of
Sustainably-Produced Food
Nutritional benefits:
Generally
higher levels of vitamins,
minerals and phytochemicals
(often dependent on soil quality)
Higher
Omega-3 content
Organic
samples contained higher
concentrations of polyphenols and
antioxidants in 75% of the matched
pairs representing those nutrients
Benefits for farm workers and
communities:
Reduced exposure to pesticides
Environment Drives Chronic Disease
Chronic
Disease
Environmental
Factors
Altered Pathways
Toxic Chemicals
Air pollution, Lead and other heavy metals,
some Pesticides,
Bisphenol A and other Endocrine Disruptors
Lead
Cumulative occupational exposure
 ↑ cognitive impairment Shih 2007
 2x risk Parkinson’s Coon 2006
Cumulative community exposure


↑cognitive impairment
Shih 2006
Up to 15 years cognitive aging Weisskopf 2004
Animal studies of early life exposure
 Late-life Alzheimer’s markers Basha 2005, Lahiri 2007
Pesticides

Parkinson’s Disease
– Human studies - 24/31 studies show ↑ risks for PD. (OR 1.6-7) Brown 2006
– Animals - Rotenone & paraquatdamage dopaminergic neurons in
striatal region of brain Uversky VN 2004
- Combinations of maneb and paraquat; prenatal
exposure “primes” the brain, increasing adult
susceptibility Cory-Slechta 2005

Cognitive decline/dementia
– Low level fungicides in vineyards 3.5x poor attention, memory Baldi 2001
– Occupational exposure in men associated with 2x risk of
developing AD Baldi 2003

Insulin Resistance, metabolic syndrome Lee 2006, 2007, 2007
– Some persistent pesticides show strong
dose-response relation to insulin resistance
and metabolic syndrome.
Bisphenol A
Found in polycarbonate plastic,
resins, sealants.


Exposures are nearly ubiquitous.

Endocrine disruptor, oxidative stress.
polycarbonate
Causes fat accumulation & insulin
resistance at low levels (animals).

Alanso-Magdelena 2006, Wada 2007

3-fold ↑ Cardiovascular disease. Lang 2008

2-fold ↑ Insulin Resistance. Lang 2008
Environmental Factors Disrupt Insulin Signaling,
Drive Inflammatory Metabolism
↓Omega-3
Saturated fat
Inflammation
Oxidative
stress
↓Antioxidants
Lead, other
heavy metals
Some
Pesticides
Air
Pollution
Insulin
signaling
Endocrine
Disruptors BPA, dioxins, PCBs,
some pesticides
• ↑ blood sugar
• ↑ artery disease
• ↑ triglycerides
High Glycemic
Carbohydrates
Fructose
Environment Drives Chronic Disease
Chronic
Disease
Environmental
Factors
Altered Pathways
Built Environment
Physical Activity
Health Benefits of Physical Activity
Increasing physical activity at any age improves
physical and emotional wellbeing.

Reduced ongoing levels of oxidative
stress and inflammatory burden.
Brooks 2008, Attipoe 2008

Inversely associated with the
risks of Alzheimer’s/dementia and
cognitive decline. Rovio 2005

Subjects at risk for AD who walked 150 min. per
week showed improvements in cognition while the
control group showed no net change from baseline
at 1.5 yrs. Lautenschlager 2008
Livable Communities Enhance Healthy Aging
Walkable Cities Projects
 Community Gardens
 Farmer’s Markets
 Rails to Trails

Sustainable Food & Transportation Solutions:
The Cuba Example
Cuba- lost fossil fuels
↑biking, walking, local plant-based food
↑physical activity 50%
↓obesity 50%
↓mortality: DM 51%, CVD 35%, stroke 20%, all cause 18%
Franco M et al. Impact of Energy Intake, Physical Activity, and Population-wide Weight Loss on Cardiovascular
Disease and Diabetes Mortality in Cuba, 1980-2005. AJE 166, 12; Sept. 19, 2007
Green Space
Reduces Stress, Mortality, Improves Cognitive Function
Shortens
post surgical
recovery time, reduces
need for pain medications.
Ulrich ‘84
Attention
deficits improve
after a walk in the park.
Effect = methylphenidate.
Taylor ’08
Access
to green space
reduces the effect of
poverty on mortality by
~50%. Mitchell ‘08
Environmental Factors Disrupt Insulin Signaling,
Drive Inflammatory Metabolism
↓Omega-3
Saturated fat
Obesity
Inflammation
Oxidative
stress
↓Antioxidants
Inactivity
Lead, other
Air
Pollution
Insulin
signaling
Endocrine
Disruptors BPA, dioxins,
PCBs, some pesticides
• ↑ blood sugar
• ↑ artery disease
• ↑ triglycerides
heavy metals
Some
Pesticides
High Glycemic
Carbohydrates
Fructose
Environment Drives Chronic Disease
Chronic
Disease
Environmental
Factors
Altered Pathways
Socio-Economic
Stress
Depression, poverty, violence,
inadequate health care
Socioeconomic, Psychosocial Stressors

Stress, depression risk for
CVD, AD Sesso, Kario, Ownby

People with lower SE status are at
risk for exposure to multiple
environmental hazards
↑damage.
– Lead + stress  ↑cognitive impairment
Glass 2009
–
Lead + air pollution ↑CV autonomic
dysfunction Park 2008
Effects of the Built Environment on Health
People who live in neighborhoods that lack social
cohesion, sidewalks, or safety limit their exercise and have
an increased risk of depression and possibly obesity.
Berke EM 07, Molnar BE 04
Environmental Factors Disrupt Insulin Signaling,
Drive Inflammatory Metabolism
Stress
↓Omega-3
Saturated fat
Obesity
Inflammation
Oxidative
stress
↓Antioxidants
Inactivity
Lead, other
Air
Pollution
Insulin
signaling
Endocrine
Disruptors BPA, dioxins,
PCBs, some pesticides
• ↑ blood sugar
• ↑ artery disease
• ↑ triglycerides
heavy metals
Some
Pesticides
High Glycemic
Carbohydrates
Fructose
Multiple
Factors
Interact to
Influence
Health
&
Disease
Environmental Factors Drive Chronic
Disease and the Climate Crisis
Climate Crisis
Environmental
Factors
Heat, drought, storms,
↑ Greenhouse fires, ice sheet
Gases
instability, sea level rise,
loss of glacial irrigation,
refugees, food
Altered
insecurity/starvation,
Biological
tropical diseases
Pathways
Chronic Disease
Solutions
for
Healthy People & A Healthy Planet
Major Illnesses Are Preventable
Personal Actions to Profoundly Reduce Risks
Personal Level – “Approaches to Healthy Living”
Eat healthy – whole, fresh, unprocessed, plant based
foods
 Avoid toxicants whenever possible


Exercise

Be socially engaged
Major Illnesses Are Preventable
Policy Initiatives to Profoundly Reduce Risks



Localized, diversified and sustainable food production
Clean, renewable energy  ↓ air pollution, chemical
exposures
Mass transit that connects with bike paths and sidewalks can
reduce air pollution & obesity

Chemical regulatory reform

“Safer substitute” programs and green product design  ↓
toxic exposures, ecosystem, wildlife contamination; job creation

Universal health care disease prevention & equitable health
care.
Major Illnesses Are Preventable
Policy Initiatives to Profoundly Reduce Risks
Examples of Specific Initiatives:
Nutrition – Reform agricultural subsidies to be directed toward
programs and practices that provide sufficient nutritious, sustainably
produced food and restore ecosystems that have been degraded by
agricultural activities.
Toxic Chemicals – Reform the national Toxic Substances
Control Act to include phase out of persistent, bioaccumulative, or
highly toxic chemicals.
Activity/Nature – Incorporate indoor and outdoor green spaces
and exercise areas into designs of nursing homes and assisted living
facilities
Acknowledgements
Based on the Report by Greater Boston Physicians for Social
Responsibility (www.psr.org/boston) and the Science and
Environmental Health Network (www.sehn.org) authored by Jill Stein
MD, Ted Schettler MD, MPH, Maria Valenti & Ben Rohrer
Primary authors of this presentation: Jill Stein MD, Ted Schettler
MD, MPH
Contributing Authors: Maye Thompson RN, PhD, Marybeth
Palmigiano MPH, Maria Valenti.
Illustrations by: Stephen Burdick Design
Permission is granted to use this presentation or individual slides with
proper acknowledgement and cited as from Environmental Threats to
Healthy Aging by Stein, Schettler et al. The authors of the presentation
do not authorize changes, and are not responsible for the accuracy of
material if changes have been made.
For more information contact:
Greater Boston
Physicians for Social Responsibility
www.psr.org/Boston
psrmabo@igc.org
Additional
References
For Mediterranean Diet Slide 28
Additional
Notes
What’s Novel in the Western Diet?
Slide 22