Public Health; obesity; health; diet; chronic diseases

1. NUTRITION AND CHRONIC
DISEASE
Overweight and obesity
Cardiovascular disease (CVD)
Coronary Heart Disease and Stroke
Diabetes mellitus

2. 2
Chronic Disease
• A long-term condition
• e.g., obesity, diabetes, and cardiovascular disease
• May be prevented or delayed with lifestyle changes
• e.g., healthier eating and more physical activity
• Projections show that chronic diseases will be the
predominant global source of morbidity and death in the
21st Century.
―…by 2020, chronic diseases will
account for almost three-quarters of all deaths worldwide, and that
71% of deaths due to ischaemic heart disease (IHD), 75% of
deaths due to stroke, and 70% of deaths due to diabetes will occur
in developing countries. The number of people in the developing
world with diabetes will increase by more than 2.5-fold, from 84
million in 1995 to 228 million in 2025. On a global basis, 60% of the
burden of chronic diseases will occur in developing countries.‖
• According to the WHO

3. Lancet 2005; 366: 1578–82

4. Interrelationships among Chronic
Diseases

5. Risk Factors for Chronic Diseases

6. Nutrition and Chronic Illness
• Historical Focus on Undernutrition
• Nutrition Transition Today
• Globalization and changing food habits
• Non-communicable diseases can be prevented and
controlled
• Chronic diseases are a major global burden
• Policies and health services should promote healthy diets

7. 7
Nutrition for Chronic Disease
Prevention and Treatment
• Dietary factors associated with 4 of the 10 leading
causes of death: coronary heart disease
(CHD), some types of cancer, stroke, and type 2
diabetes
• Nutrition is a widely accepted tool for prevention
of chronic diseases
• also very important for management and treatment of a
chronic diseases

8. Worldwide Obesity Epidemic
• Obesity now classified as a disease by AMA
• 2.5 million deaths can be attributed to overweight/obesity
worldwide
• Nearly 70% of cases of CVD associated with obesity
• Worldwide, more than 1.1 billion overweight adults
• At least 312 million of them are clinically obese
• By the end of 2010, an estimated 43 million children under five will be
overweight
• Obesity levels range from 20-30% in European
countries, to over 70% in Polynesia
• By 2015, the worldwide obese population will reach
1.5 BILLION
8

9. 9
Obesity and Nutrition Transition
“Obesity in the developing world can be seen as a
result of a series of changes in diet, physical
activity, health and nutrition, collectively known as
the 'nutrition transition.' As poor countries become
more prosperous, they acquire some of the benefits
along with some of the problems of industrialized
nations.”

10. 10

11. • Since mid-
seventies, prevalence of
overweight and obesity
has increased sharply for
both adults and children.
• Now more than 2/3 of U.S
adults are overweight or
obese
• Obesity rates are expected
to increase

12. Classification
BMI(kg/m�)
Principal cut-off points
Underweight
12
Additional cut-off points
<18.50
<18.50
<16.00
<16.00
Moderate thinness
16.00 - 16.99
16.00 - 16.99
Mild thinness
17.00 - 18.49
17.00 - 18.49
Severe thinness
Normal range
Overweight
18.50 - 24.99
≥25.00
Pre-obese
25.00 - 29.99
Obese
≥30.00
Obese class I
30.00 - 34-99
Obese class II
35.00 - 39.99
Obese class III
≥40.00
http://apps.who.int/bmi/index.jsp?introPage=intro_3.html
18.50 - 22.99
23.00 - 24.99
≥25.00
25.00 - 27.49
27.50 - 29.99
≥30.00
30.00 - 32.49
32.50 - 34.99
35.00 - 37.49
37.50 - 39.99
≥40.00

13. What causes obesity? Inside-the-Body
Theories
• Set-point theory
• Body organs regulate body fatness
• Thermogenesis
• Brown adipose tissue (BAT)
• Genetics and obesity
• Influence tendency to gain weight or stay lean
• Environmental factors
• Microbes in gut?

14. What causes obesity? Outside-the-Body
Theories
• External cues to
overeating
• Available foods
• Human sensations
• Larger portions
• Food supply
• Addictive?
• Dopamine
• HFCS???
• Physical inactivity
• Screen time
• Sedentary jobs
• Neighborhoods
• Built environment
• Food deserts

15. Estimated intakes of total fructose (•), free fructose (▴), and high-fructose corn syrup
(HFCS, ♦) in relation to trends in the prevalence of overweight (▪) and obesity (x) in the United
States.
Bray G A et al. Am J Clin Nutr 2004;79:537-543
©2004 by American Society for Nutrition

16. The role of genetics in body weight
• Epidemiological evidence shows that obesity, excess
energy (Calorie) intake, and sedentary lifestyle are
primary contributors to the chronic disease epidemic
• 40% of BMI is attributable to independent genetic influences
16

17. Nutritional Genomics Research
• Nutritional genomics
• Epigenetics
• Nutritional genomics researchers
strive to:
• Identify genes
• Explain the mechanisms
• Develop practical applications

18. Epigenetics
• Epigenome
• Proteins and other molecules
that regulate expression of
genes
• Turning genes “on” and “off”
• Inherited or altered
• Cell differentiation
• Regulation
• Histones
• Methyl groups

19. 19
Value of waist circumference
• Risks of visceral fat/Subcutaneous
fat
• Increases risk of death from all
Higher risk body
shape
causes
• Metabolic syndrome
• Location of excess fat is important
• If excess fat is mainly around
midsection = more likely to develop
health problems than if excess fat is
mainly around hips and thighs
• Apple vs. Pear shapes
• True even if BMI falls within the normal
range
• Women: waist measurement of
more than 35 inches (88 cm)
• Men: waist measurement of more
than 40 inches (102 cm)
Lower risk body
shape

20. Visceral Fat and Subcutaneous Fat

21. Nutrition and CVDs
• Coronary vascular disease (CVD) Caused by disease of
the blood vessels (atherosclerosis) of the heart, usually
as part of the process which affects blood vessels more
generally
• Stroke and heart disease are the main cardiovascular
diseases
• Stroke is the main cardiovascular disease in many east
Asian countries

22. Major Risk Factors for Heart Disease

23. Atherosclerosis and CVD
• Atherosclerosis is a generalized and progressive
disease that effects the arterial circulation
• major result of atherosclerosis is heart attack and stroke,
• myocardial infarctions, and angina.

24. Atherosclerosis epidemilogy
• World Health Report documents that CVD has
overtaken infectious disease as leading cause of
death worldwide representing 23% of all deaths.
• In US CVD , affects over 71 million individuals
with an annual mortality exceeding 900,000 per
year.
• costs taxpayers approximately 400 billion dollars per year

25. How Does It Start?
• Atherosclerosis usually begins with the epithelium, the
inner most layer of the artery.
• Damage can occur because of elevated
cholesterol, high blood pressure, tobacco smoke, and
diabetes.
• Buildup occurs thickening the arterial wall, decreasing
blood flow, and reducing the oxygen in the blood.

26. The Five Phases of Atherosclerosis
• Phase One: LDL deposits into
cells of inner wall of the artery
• Phase Two and Three:
inflammatory cells move into
vessel wall and the plaque
continues to grow, a fibrous
cap formed
• Phase Four: smooth muscle
cell proliferation changes and
begins to break down, the
fibrous ruptures or the plaque
is exposed to the blood
stream, the plaque contains
materials which encourage
clotting
• Phase Five: platelets are
attracted to this prothrombotic
material and a clot forms in the
vessel which may interrupt
blood flow and damage tissues

27. Heart Disease is NOT a Man’s Disease
• Women tend to develop heart disease about ten years
later than men.
• Many public health initiatives have relied on studies
comprised disproportionately of men.
• In 1991, NHI launched the Women’s Health Initiative to
study the affects of different treatments, dietary
modifications, and supplements on generally healthy post
menopausal women.

28. Stroke
• occurs when blood flow to the brain is interrupted by a clot
in a artery or other vessel. When this occur brain cells
begin to die and brain damage occurs.
• U.S., approximately 700,000 new strokes per year and
500,000 new transient ischemic attacks (TIAs).
• Stroke is 3rd leading cause of death in US and leading
cause of disability.
• Stroke cost US an estimated $62.7 billion dollars in 2007.

29. Racial/Ethnic Considerations
• In the US, African Americans have a nearly 2
times higher occurrence of first time stroke than
Caucasians and have 1.5 times greater death
rates from stroke than Caucasians.
• Atherosclerosis also affects different groups at
different sites.
• Caucasians: common site is carotid artery in neck.
• African Americans: intracranial arteries more commonly
involved.

30. Pathophysiology
• When blood flow is interrupted the brain can not get the
glucose or oxygen it needs.
• The mitochonria that rely on O2 can not maintain the
electrical state of the neuron.
• This change in the electrical state cause communication
between cells to cease, as well as trigger apoptosis.

31. Two Major Types of Strokes
• Ischemic stroke: blood flow
to brain region is interrupted
due to a artery blockage
• Accounts for the
majority, approximately 80-85%.
• Caused by direct blockage
or a clot from elsewhere
• Hemorrhagic stroke: due to a
rupture of blood vessel; result of
hypertension, bleeding
disorders, tumors, vascular
disease.2 types:
• intracerebral
hemorrhage(ICH)
• subarachnoid hemorrhage
(SAH)

32. Symptoms of Stroke
• Inability to move or feel parts of the body
(face, arm, hand or leg) on one side
• Inability to speak or understand speech
• Any loss of vision (in one eye or to one
side)
• Double vision
• Dizziness/vertigo
• Confusion
• Sudden severe headache

33. Stroke Treatment: Time is Tissue
• If caught early (3-6 hours) can be treated with clot
dissolving medication tPA (tissue plasminogen activator).
• At present, only about 5-10% of acute stroke patients will
receive tPA therapy.

34. Recommendations for Reducing CVD
Risk

35. Recommendations for Reducing CVD
Risk
• Diet to reduce CVD risk
• Reduce fat intake
• Saturated and trans fats
• Limit refined starches and added sugars
• Eat fruits, vegetables, and whole grains
• Diet rich in omega-3 fatty acids
• Other dietary factors

36. American Heart Association (AHA) 2006
Diet and Lifestyle Recommendations for
Cardiovascular Disease Risk Reduction
• Balance calorie intake and physical activity to achieve
or maintain a healthy body weight.
• Consume a diet rich in vegetables and fruits.
• Choose whole-grain, high-fiber foods.
• Consume fish, especially oily fish, at least twice a week.
• Limit intake of saturated fat to 7% of energy, trans fat to
1% of energy, and cholesterol to 300 mg per day by:
— choosing lean meats and vegetable alternatives;
— selecting fat-free (skim), 1%-fat, and low-fat
dairy products;
— minimizing intake of partially hydrogenated fats

37. Nutrition and Hypertension
• One of most prevalent forms of CVD
• According to American Heart Association (2007) 1 in 3 U.S.
adults has high blood pressure, but because there are no
symptoms, nearly 1/3 rd of these people don't know they have
it.
• Uncontrolled high blood pressure can lead to stroke, heart
attack, heart failure or kidney failure.
• high blood pressure is often called the "silent killer.―
• In a healthy adult blood pressure is 120/80 mmHg
• Systolic pressure: refers to the level of blood pressure while
heart is contracting; is represented by top number (120 mmHg).
• Diastolic pressure level of blood pressure in between heart
contractions; represented by the bottom number.

38. Factors Contributing To Blood Pressure
• 2 factors,
• cardiac output, volume of blood pumped by heart each minute,
• resistance to blood flow in the vessels, primarily the arterioles.
Vascular resistance is result of friction as blood
flows through vessels
< diameter of vessels the > resistance.
Relationships among pressure, flow and
resistance quite simple: Pressure = flow X
resistance

39. Kidney – Blood Pressure Relationship
• By regulating the total volume of the extracellular fluid
(ECFV), kidneys control blood volume.
• If ECFV and blood volume increases, blood pressure increases
• ECFV regulated, in large part, by total body sodium
levels, which are regulated by variable sodium excretion in
urine.
• Sodium ion (Na+) balance determines ECFV, blood volume
and blood pressure
• To stay in balance, Na+ eaten must equal Na+ lost
• most Na+ is lost in urine.
• 70% of Na+ reabsorbed in the proximal tubule
• Fine regulation of Na+ excretion takes place in distal tubule and
collecting ducts
• Renin-angiotensin hormone system (RAAS) regulates sodium
excretion.
• RAAS activated by reduced blood volume or low blood sodium
concentration

40. Water Balance
• Water is added to ECF by drinking and oxidative
metabolism.
• lost mostly in expired air, sweat and urine.
• amount of water lost in urine is controlled by antidiuretic
hormone vasopressin.
• Vasopressin decreases urinary water loss.
• Vasopressin levels increase in response to
dehydration, blood loss and angiotensin II.

41. Treatment Of Hypertension- Drugs That Target
Kidney Function
• Diuretics such as Lasix – Block sodium reabsorption
and increases urine volume
• Spironolactone and Eplerenone block aldosterone
action
• ACE inhibitors block conversion of Angiotensin I to
angiotensin II
• Losartan blocks binding of angiotensin II to cellular
receptors

42. Nutrition and Hypertension
Guidance to prevent or
reduce high blood pressure
• Choose and Prepare Foods
with Little or No Salt
• In some people, sodium
increases blood pressure
because it holds excess fluid in
body, creating an added burden
on the heart
• Dietary Approaches to Stop
Hypertension (DASH)
• Health benefits beyond blood
pressure
• Weight control
• Physical activity
• Alteration of hormones

43. The DASH Diet: Preventive Medicine
• Dietary guidelines
• Fruits and vegetables
• More Matters
• Make only a few dietary
changes at a time

44. 44
Diabetes
• Characterized by increased blood glucose (sugar)
levels
• Due to
1. a lack of insulin (a hormone), which controls
blood glucose levels
And/Or
2. an inability of the body’s tissues to respond
properly to insulin (a state called insulin
resistance)
• The most common type of diabetes is type 2
• Diabetes can benefit from good nutrition

45. Diabetes Epidemiology
• 4th leading cause of death by disease globally
• Prevalence has doubled since 1991
• 7.0 million to 14.6 million (2005)
• 6.2 million people unaware they have diabetes
• Almost 10 % of population aged 20 years or older has
diabetes
• 1.5 million new cases were diagnosed in 2005.
• Projected prevalence will exceed 29 million in year 2050

46. 46
Types of Diabetes
• Type 1 diabetes
• an autoimmune condition resulting in the need for
lifelong insulin therapy
• Type 2 diabetes
• Progressive disease related to insulin resistance
• May be managed with just diet and exercise, or may
require oral medication and/or insulin injections
• Most commonly seen in overweight/obese people, but can
also develop in normal weight people
• Gestational Diabetes
• Diabetes that develops during pregnancy

47. Relative Risk of Diabetes for race/ethnicity population as
compared to non-Hispanic whites among people age 20
years or older in the United States, 2005
Non-Hispanic white
1.0
American Indians and Alaska Native
2.2
African Americans
1.9
Mexican Americans
1.7
Asians, native Hawaiians and Pacific Islanders in Hawaii
2.0
California Asians
1.5
CDC Diabetes, National Diabetes Fact Sheet: United States, 2005. Accessed March 2007
at http://www.cdc.gov/diabetes/pubs/pdf/ndfs_2005.pdf

48. Complications
• Macrovascular complications
• coronary artery disease
• stroke
• peripheral vascular disease
• Microvascular complications
• retinopathy
• nephropathy
• neuropathy
EVERY 24 HOURS
• New Cases - 4,100
• Deaths - 810
• Amputations - 230
• Kidney Failure - 120
• Blindness – 55

49. Nutrition and Diabetes
Nutrition-related risk factors of Diabetes
•
•
•
•
BMI 25 or more
Prediabetes: Impaired glucose tolerance and
impaired fasting glucose
Lack of regular exercise
Abnormal lipid levels

50. Diabetes prevention: 5 steps
•
•
•
•
•
Losing extra weight
Eating plenty of fiber
Skipping fad diets
Choosing whole grains
Getting more physical activity

51. 51
Overall Preventing Chronic Diseases
• Nutrition in the Management of Dietary Changes
• Energy density
• Nutrient-rich foods
• The right carbohydrates
• Limit sweets and reduce fat
• Portion sizes and count calories
• Increase Physical Activity
• Maintain a healthy body weight
• The WHO goals are
• For an adult median BMI of 21 to 23 kg/m2
• For individuals, the recommendation is to maintain a BMI in the
range 18.5 to 24.9 kg/m2 and to avoid a weight gain greater than 5
kg (11 pounds) during adult life