Transcript Diet and Health Guidelines to Lower Risk of Cardiovascular Disease

Diet and Health Guidelines to Lower
Risk of Heart Disease
Presented by
Janice Hermann, PhD, RD/LD
OCES Adult and Older Adult Nutrition Specialist
Cardiovascular Disease
 Cardiovascular disease describes diseases of
the heart and blood vessels
 Coronary heart disease
 Stoke
 Hypertension
 Congestive heart failure
Cardiovascular Disease
 Coronary heart disease is the most common
form of cardiovascular disease
 Usually caused by atherosclerosis
 Stroke is the second most common form of
cardiovascular disease
Atherosclerosis
 Thickening of the blood vessel walls due to
plaque formation (accumulation of lipids,
smooth muscle cells, minerals and fibrous
connective tissue)
Atherosclerosis Development
 Initiated by minimal but chronic injuries that
damage the blood vessel lining
 Oxidized LDL cholesterol accumulates in blood
vessel wall
 Blood vessel damage causes inflammation
 Immune system responds sending white blood
cells
 White blood cells enter blood vessel wall,
engulf LDL cholesterol, forming foam cells
 Foam cells visible as fatty deposits along blood
vessel wall, known as fatty streaks
Atherosclerosis Development
 Smooth muscle cells from blood vessel tissue
stimulated to divide, engulf LDL cholesterol
and form fibrous connective tissue
 Plaque accumulates calcium and cholesterol
in lipid core can crystallize and harden
 Sometimes the blood vessel may expand
outward to accommodate the plaque volume;
other times plaque narrows the blood vessel
lumen
Atherosclerosis Development
 Atherosclerosis
Development
 Injury
 Oxidized LDL accumulates
 Damage causes
inflammation
 Immune system responds
with white blood cells
 Engulf LDL cholesterol forming
foam cells
 Smooth muscle
proliferation
 Lipid, mineral accumulation
 Maturation of lesion
Inflammation and Infection
 As mentioned plaque formation is initiated by
an inflammatory response to injuries that
damage the blood vessel lining
 There is also evidence that persistent
infection may contribute to plaque formation
 This has led to the use of markers indicating
artery wall inflammation
 A promising marker is a protein known as C-
reactive protein (CRP), which is produced during
the acute phase of inflammation
Plaque
 Plaque can exist in two forms:
 A stable form
 Has a thicker barrier between its lipid core and the blood
vessel lumen
 Blood vessels that accommodate plaque only by
narrowing may impede blood flow, but generally have
more stable plaque
 An unstable plaque
 Has a thin barrier which is highly susceptible to rupture
resulting in blood clot formation
 Blood vessels that accommodate plaque by expanding
are less likely to interfere with blood flow but generally
have unstable plaque
Blood Clots
 Blood clots can enlarge over time
obstructing blood flow or a clot may break
free and travel through the circulatory
system until it lodges in a narrowed artery
and obstruct blood flow
 When blood flow is obstructed the
surrounding tissue is deprived of oxygen
which results in cell death
 Heart – heart attack
 Brain – stroke
 Lung – pulmonary embolism
 Kidney – acute renal failure
Aneurysm
 Atherosclerosis also is a risk factor for
aneurysms
 An aneurysm is an abnormal enlargement within
the blood vessel
 Plaque can weaken the blood vessel wall, allowing
it to expand and balloon out
 Aneurysms that go undetected can rupture and
lead to massive bleeding and death
Coronary Heart Disease Risk Factors
 Some factors initiate atherosclerosis by:
 Causing direct damage to the artery wall
 Allowing lipid materials to penetrate artery surface
 Other factors promote progression of
atherosclerosis and related complications by
inducing:
 Plaque rupture
 Blood clotting
Coronary Heart Disease Risk Factors
 Non modifiable risk factors:
 Increasing age
 Gender
 Family history of premature heart disease
 Modifiable risk factors:
 High LDL cholesterol
 Low HDL cholesterol
 High blood pressure
 Diabetes
 Obesity (especially abdominal obesity)
 Physical inactivity
 Cigarette smoking
 Diet high in saturated fat, trans fat, and
cholesterol and low in fruits, vegetables and
whole grains
Preventing Coronary Heart Disease
 For most people, preventing coronary heart
disease focuses on lowering modifiable risk
factors
 Studies have suggested that 80 to 90 percent
of people with severe heart disease have at
least one of the four classic risk factors:
 High LDL cholesterol
 High blood pressure
 Diabetes
 Smoking
Age
 Aging strongly associated with atherosclerosis
due to:
 Cumulative exposure to risk factors
 Degeneration of blood vessels with age
 Aging becomes a significant risk factor for:
 Men at age 45 or older,
 Women at age 55 or older as they reach
menopause
Gender
 Gender difference in age of coronary heart
disease onset has been attributed to:
 A protective effect of estrogen in women
 Men also tend to have other possible risk factors:
 Higher homocysteine levels
 Higher risk of iron overload
 Ultimately, coronary heart disease kills as
many women as men
Family History
 Family history of early coronary heart disease
in one’s immediate family members is an
independent risk factor, independent of other
risk factors
LDL cholesterol
 LDL cholesterol is easily oxidized
 Oxidized LDL cholesterol is actively taken up
and retained in the blood vessel wall
 Oxidized LDL has other damaging effects:
 Activate proliferation of smooth muscle cells
involved in plaque formation
 Induce vasoconstriction (increase blood pressure)
 Simulate blood clotting
 Inhibit some normal protective functions of HDL
LDL cholesterol
 High levels of a variant form of LDL called
lipoprotein(a) has been found to accelerate
progression atherosclerosis and double the
risk of coronary heart disease
 Abnormally high levels are largely genetically
determined and have been associated with
premature development of heart disease
LDL Cholesterol Levels
 High LDL cholesterol ≥ 160 mg/dL
 Recommended LDL cholesterol < 100 mg/dL
HDL Cholesterol
 HDL carries cholesterol from body cells to the
liver to be removed and thus protects against
atherosclerosis
 Low HDL cholesterol is a risk factor for
coronary heart disease
 Low HDL cholesterol levels often coexist with
other risk factors such as high triglycerides
 Some factors that increase coronary heart
disease risk such as obesity, smoking,
inactivity and male gender also reduce HDL
HDL Cholesterol
 Low HDL < 40 mg/dL
 Recommended HDL ≥ 60 mg/dL
Blood Pressure
 The stress of blood flow along the blood
vessel walls (shear stress) can cause
mechanical damage within the blood vessel
 Plaque tends to develop at points where blood
vessels branch or bend disturbing blood flow
 High blood pressure intensifies the stress of
blood flow on arterial walls
 Plaque protruding inward can reduced blood
flow and raise blood pressure even further
 Thus, hypertension and atherosclerosis
become mutually aggravating conditions
Blood Pressure
 For people over 50 years of age, a high
systolic blood pressure is more predictive of
coronary heart disease risk than diastolic
blood pressure
 High blood pressure is ≥140/ ≥90 mm Hg
 Recommended blood pressure is <120/<80
Diabetes
 High blood glucose can attach (glycate) to
proteins forming glycoproteins
 These proteins can damage blood vessels and
worsen atherosclerosis
 Other effects of diabetes promote blood clot
formation
Diabetes
 High fasting blood glucose is ≥ 126 mg/dL
 Recommended fasting blood glucose is < 100
mg/dL
 High 2 hr OGT blood glucose is ≥ 200 mg/dL
 Recommended 2 hr OGT blood glucose is
< 140 mg/dL
Obesity (Especially Abdominal)
 Obesity, especially abdominal obesity,
increases the risk of coronary heart disease by:
 Increasing blood pressure
 Increasing insulin resistance
 Increasing risk of diabetes
 Increasing LDL cholesterol
 Increasing triglycerides
 Lowering HDL cholesterol
 Alters concentration and activity of blood clotting
factors promoting blood clotting
Obesity (Especially Abdominal)
 Overweight = BMI 25.0-29.9
 Obese = BMI ≥ 30
 Recommended BMI = 18.5 – 24.9
 Recommended waist circumference is:
 Men: <102 cm (<40 in)
 Women: <88 cm (<35 in)
Obesity
 The initial goal of a weight-loss program is no
more than 10% of original body weight
 For some, avoiding additional weight gain
may be a desirable starting point
Physical Inactivity
 Physical inactivity can increase risk of:
 Low HDL cholesterol
 Obesity
which can increase the risk of:
 Diabetes
 High blood pressure
 Regular physical activity can lower coronary
heart disease risk:
 Increase HDL
 Lower LDL cholesterol
 Lower triglycerides
 Promote weight loss
 Improve insulin sensitivity
 Lower blood pressure
 Strengthen heart muscles
Physical Activity
 Aerobic activities help the heart the most
 Goal is to expend at least 2,000 calories in
physical activity per week
 Dietary Guidelines physical activity
recommendations:
 For substantial health benefits
 150 minutes of moderate-intensity per week or
 75 minutes of vigorous-intensity per week
 For additional health benefits
 300 minutes of moderate-intensity per week or
 150 minutes of vigorous-intensity per week
Cigarette Smoking
 Substances in smoke:
 Induce vasoconstriction
 Increase blood pressure
 Damage blood vessels
 Injure blood vessel walls
 Increase oxidative stress
 Promote LDL cholesterol oxidation
 Damage platelets
 Promote blood clotting
 Decrease oxygen carrying capacity of blood
 Promote lipid accumulation in blood vessel walls
Cigarette Smoking
 Passive smoke has similar effects
 Recommendations are to not start smoking or
to quit smoking and to avoid second hand
smoke
 Quitting smoking can improve coronary heart
disease risk almost immediately, and people
who stop smoking can eventually reverse the
damage from smoking
Diet
 A diet high in saturated fat, trans fat, and
cholesterol and low in fruits and vegetables,
and whole grains is associated with increased
coronary heart disease risk, even more than
might be expected based on risk factors such as
LDL cholesterol alone
 High in nutrients that increase coronary heart
disease risk such as saturated fat, trans fat and
cholesterol
 Low in nutrients that decrease coronary heart
disease risk such as fiber, omega-3 fatty acids, and
antioxidants
Saturated Fat
 Saturated fat has the strongest effect of all
lipids on blood LDL cholesterol levels
 Clinical trials suggest every 1% increase in calories
from saturated fat raises LDL cholesterol 2%
Saturated Fat
 Replacing saturated fat with
monounsaturated or polyunsaturated fats can
lower LDL cholesterol levels
 Polyunsaturated fats have a slightly greater effect
on lowering LDL cholesterol, but can also promote
a slight reduction in HDL cholesterol
Saturated Fat
 Average American diet provides 11% of total
calories from saturated fat
 Main sources of saturated fat are whole-milk
products, high fat meats, and baked goods
 Recommendations are to choose lean meats or
fish, use fat-free or low-fat milk products, limit
snack foods and bakery products high in saturated
fat
Saturated Fat
 Replacing saturated fats with carbohydrates
can also reduce LDL cholesterol but may
lower HDL cholesterol and raise triglycerides
 This effect can be offset somewhat by limiting
added sugars and including fiber-rich foods;
generous amounts of whole grains, legumes, fruits
and vegetables
 DRI recommended carbohydrate intake is 45-65%
of total calories
Saturated Fat
 Dietary Guidelines recommendations are:
 Total fat
 20 to 35% total calories
 Saturated fat
 < 10% total calories
Saturated Fat - Tropical Oils
 Although, liquid a room temperature, tropical
oils are highly saturated
 Coconut oil (92% saturated)
 Palm kernel (82% saturated)
 Palm oils (50% saturated)
Saturated Fat - Steric Acid
 Stearic acid is a saturated fatty acid that is
mainly in animal products, and some plant
foods like chocolate
 Studies have shown saturated fatty acids raise
blood cholesterol
 However, other studies show that some
saturated fatty acids like stearic acid may not
affect or ay even lower total blood cholesterol
 Further research is needed
Saturated Fat - Hydrogenated Fats
 Process of hydrogenation changes a liquid oil,
naturally high in unsaturated fatty acids, to a
more solid and more saturated fat
 The greater the degree of hydrogenation, the
more saturated the fat becomes
Trans Fat
 Trans fat result from hydrogenation of
vegetable oils
 Unsaturated bonds change from a cis to trans
configuration
 Trans fats are unsaturated, but they can raise
LDL cholesterol
 When trans fats replace saturated fats in the
diet they can lower HDL cholesterol
Trans Fat
 Most sources of trans fats are products made
with partially hydrogenated oils
 Baked goods like crackers, cookies, and doughnuts,
and fried foods like french fries and fried chicken
 Soft margarines and other products are now
available with little, or no, trans fat
 Current trans fat intakes average about 2.6%
of calories
 Dietary Guideline recommendations are to
keep trans fat intake as low as possible
Dietary Cholesterol
 Although saturated fat is the main culprit in
raising blood cholesterol, dietary cholesterol
plays a part
 Dietary cholesterol also raise LDL cholesterol, but
not as much as saturated fat
Dietary Cholesterol
 People get cholesterol in two ways:
 Liver production
 About 1,000 mg/day
 Foods also contain cholesterol
 Average intake 331 mg/day men and 211 mg/day
women
 Animal products (egg yolk, meat, poultry, fish seafood,
whole milk dairy products) contain cholesterol
 Plant foods (fruits, vegetables, grains, nuts and seeds) do
not contain cholesterol
Dietary Cholesterol
 Dietary Guideline recommendations are:
 Limit dietary cholesterol intake to < 300 mg/day
Soluble Fiber
 When eaten as part of a diet low in saturated
fat, trans fat and cholesterol, soluble fiber has
been shown to help lower blood cholesterol
 Soluble fibers can:
 Reduce cholesterol and bile absorption by binding
them in the intestinal tract
 May also influence the liver’s production of
cholesterol by other means
Soluble Fiber
 Dietary sources of soluble fiber include oats,
barley, legumes, and fruits
 The soluble fiber from psyllium seed husks is
also effective for lowering cholesterol levels
Fiber
 Dietary fiber intake in the United States
averages about 15 g/day
 Many organizations recommend dietary fiber
intake should be 20 – 30 g/day
 DRI for fiber is 14 g/1,000 calories
 Would be 28 g for a typical 2,000 calorie diet
Omega-3 Fatty Acids
 Fatty fish are high in two omega-3 fatty acids:
 Eicosapentaenoic acid (EPA)
 Docosahexaenoic acid (DHA)
 Fatty fish
 Mackerel
 Lake trout
 Herring
 Sardines
 Albacore tuna
 Salmon
Omega-3 Fatty Acids
 Omega-3 fatty acids may be beneficial by:
 Suppressing inflammatory response
 Reducing blood clotting time
 Stabilizing heart rhythm
 Lowering triglyceride levels
 Large intakes of EPA and DHA, however, may
raise LDL cholesterol in some people
 Increasing omega-3 fatty acids through foods
is preferred to supplements
 Not all studies with fish oil supplements have
reported positive outcomes
Omega-3 Fatty Acids
 Omega-3 fatty acids found in flaxseeds and
other land plants have lesser or different
effects than omega-3 fatty acids from marine
sources
 Although limited evidence suggests these plant
sources of omega-3 fatty acids may lower coronary
heart disease risk, more research is needed to
confirm their benefits
Antioxidants
 Oxidized LDL is especially atherogenic
 Epidemiological studies suggest an
association between diets rich in antioxidants
(fruits, vegetables and whole grains) and
lower coronary heart disease risk
 However, antioxidant rich diets are often
linked with a healthy lifestyle and lower body
weight making it difficult to determine which
factor is responsible for the effect
Antioxidants
 Controlled trials with single antioxidant
supplements (vitamin C and E), combinations,
or multivitamins have produced results too
weak or inconsistent to conclude that they
offer any significant benefit for preventing
coronary heart disease, and several studies
have suggested possible harm
 Recommendations are to eat a diet rich in
fruits, vegetables and whole grains
Alcohol
 Coronary heart disease risk is lower for
people who drink moderate amounts than
nondrinkers
 Moderate amounts of alcohol has favorable
effects on:
 HDL cholesterol levels
 Atherosclerosis
 Inflammation
 Blood clotting activity
Alcohol
 Moderate intake defined as:
 1 drink for women or 2 drinks for men/day
 One drink is:
 1 ½ fl oz of 80 proof
 1 fl oz 100 proof
 4 fl oz wine
 12 fl oz beer
Alcohol
 Too much alcohol:
 Raise blood pressure
 Raise blood triglycerides
 Contribute to obesity
 Associated with certain types of cancer
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

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Gastrointestinal tract
Liver
Breast
Ovarian
 For these reasons, nondrinkers are not
encouraged to start drinking in an effort to
decrease coronary heart disease risk
Soy
 Several studies have shown diets low in
saturated fat and cholesterol and high in soy
protein can reduce LDL cholesterol levels,
especially when soy protein replaces foods
that contain animal fats
 Approximately 25 grams of soy protein daily
appears to be needed for significant benefit
 Whether the LDL lowering effect is due to soy
protein alone or to other components of soy, such
as isoflavone or sapoinins, remains unclear
Plant Sterols
 Plant sterols can lower blood cholesterol
 Reduce intestinal absorption of cholesterol, both
dietary cholesterol and cholesterol in bile
 Clinical trials have shown a little more than one
tablespoon of margarine daily (containing about 2
grams of plant sterols) can lower LDL cholesterol
by 6-15% without lowering HDL cholesterol
 One concern is plant sterols may also reduce
absorption and blood levels of carotenoids
 Unknown if eating more fruits and vegetables could
compensate
Plant Sterols
 Plant sterols are extracted from soybeans and
pine-tree oils
 They can be hydrogenated to produce plant
stanols, which are compounds typically found in
commercial products
 Food manufacturers have designed
margarines, cheese, and other products with
added plant sterols
Folate acid, B6 and B12
 High homocysteine levels related to
atherosclerosis and coronary heart disease
risk
 Folate, B6 and B12 help break down and lower
homocysteine in the body
 Use of folate, B6 and B12 supplements to reduce
coronary heart disease risk is not recommended
 Recommendations are to get enough folate, B6 and
B12 in the diet from fruits and green leafy
vegetables
Emerging Coronary Heart Disease
Risk Factors
 There are other emerging physiological
factors that appear to influence coronary
heart disease risk:
 Metabolic syndrome
 Hypertriglyceridemia
 Homocysteine
 Iron Overload
Metabolic Syndrome
 Metabolic syndrome is a condition of having
three or more of the following abnormalities:
 Abdominal obesity
 Waist circumference > 40 inches (men)
 Waist circumference > 35 inches (women)
 Serum triglycerides ≥ 150 mg/dl
 HDL < 40 mg/dl in men or < 50 mg/dl in women
 Blood pressure ≥ 135/85 mm Hg
 Serum glucose ≥ 110 mg/dl
Metabolic Syndrome
 Each of these factors increases the likelihood
of developing coronary heart disease
independently, but when they occur together,
they elevate risk synergistically
 Estimates are that approximately 24% of the
population have metabolic syndrome
Metabolic Syndrome
 Recommendations for people with metabolic
syndrome are:
 Weight loss to achieve BMI less than 25 to support
reduced abdominal obesity, reduce triglycerides,
and reduce blood pressure
 Increased physical activity to support weight loss,
glucose control, reduce triglycerides, reduce blood
pressure and increase HDL cholesterol
 Healthy eating habits that support weight loss,
glucose control, reduce blood pressure and reduce
triglycerides
Triglycerides
 Whether high triglycerides are an
independent risk factor for coronary heart
disease remains debatable
 High triglycerides is common in people with
metabolic syndrome and diabetes
 High triglycerides are associated with low HDL
 Overweight, sedentary lifestyle, and cigarette
smoking all may raise triglyceride levels
 Dietary factors that influence triglycerides the
most are high intakes of carbohydrate (≥60%
of total calories) and alcohol
Triglycerides
 High blood triglycerides is ≥ 200 mg/dL
 Recommended blood triglycerides is < 150
mg/dL
Triglycerides
 High blood triglycerides is ≥ 200 mg/dL
 Recommended blood triglycerides is < 150
mg/dL
Homocysteine
 High homocysteine related to atherosclerosis
and coronary heart disease risk
 Damage blood vessel walls
 Increase oxidative stress
 Increase blood clotting activity
 Uncertain whether harmful effects caused by
homocysteine or something associated with it
 Folate, B6 and B12 help break down
homocysteine in the body
Iron Overload
 Iron overload, more common in men, is
associated with increase coronary heart
disease risk
 Iron overload increases oxidative stress
 More research is needed to understand iron’s
role in coronary heart disease