Diet and Health. 2 Introduction 2 main kinds of diseases afflict people worldwide: Infectious...

Diet and Health

2

Introduction2 main kinds of diseases afflict

people worldwide:• Infectious diseases

– Diseases that are caused by bacteria, viruses, parasites, and other microbes

– Can be transmitted from one person to another through air, water, food or contact; or through vector organisms such as mosquitoes and fleas

• Degenerative diseases – Chronic, irreversible diseases characterized by

degeneration of body organs– Due in part to such personal lifestyle elements as

poor food choices, smoking, alcohol use, and lack of physical activity

– Also called lifestyle diseases, chronic diseases, or the diseases of age

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Introduction• Infectious diseases have been major

killers of humankind since before the dawn of history– In any society not well defended against

them, infectious diseases can cut life short so that people die at 20, 30, or 40 years of age

• With the advent of vaccines and antibiotics, people in developed countries had become complacent about infectious diseases - until the threat of bioterrorism became an issue.

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Introduction• Individuals can take steps to protect

themselves from disease– Although nutrition cannot directly prevent or

cure infectious diseases, it can strengthen or weaken your body’s defenses against them•“immune-strengthening” foods, dietary

supplements, and herbs are hoaxes•The best help you can provide your

immune system is to nourish it properly to ensure that it works to its capacity every day

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•In developed nations, degenerative diseases far outrank infections as the leading cause of death and illness

•The longer a person lives, the more likely to occur!

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Introduction• Degenerative diseases do not arise

from a straightforward cause such as infection– But from a mixture of three factors

• Genetic predisposition• Personal medical history• Lifestyle choices

– As people age, their bodies accumulate the effects of the lifestyle choices• In the later years these impacts can make the

difference between a life of health or one of chronic disability

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Nutrition and Immunity

• Deficient intakes of many vitamins and minerals are associated with impaired disease resistance– As are some excessive intakes

• Immune tissues are among the first to be impaired in the course of a nutrient deficiency or toxicity

• Some deficiencies are more immediately harmful than others– The speed of the impact is affected by

• Whether another nutrient can perform some of the metabolic tasks of the missing nutrient

• How severe the deficiency is• Whether an infection has already taken hold• The person’s age

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• Once a person becomes malnourished, malnutrition often worsens disease, which, in turn, worsens malnutrition

• The cycle often begins when impaired immunity opens the way for disease– The disease impairs food

assimilation, and nutrition status suffers further

– Drugs become necessary, and many of them impair nutrition status even further

– Treatments, such as surgery, take a further toll

– Young, old, sick, poor, hospitalized most susceptible

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• Malnutrition can result not only from a lack of available food but also from diseases, such as AIDS and cancer, and their treatments

• These conditions alter the appetite and metabolism– Causing a wasting of the body’s tissues

similar to that seen in the last stages of starvation

– The body uses its fat and protein reserves for survival

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Lifestyle Choices and Risks of Degenerative Disease

• Degenerative diseases of adulthood have suspected contributors known as risk factors– Factors known to be related to (or

correlated with) diseases but not known to be causal•Environmental factors•Behavioral factors•Social factors•Genetic factors

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Many of these conditions are also risk factors for other degenerative diseases

Note: Obesity is linked to all of the degenerative diseases

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Lifestyle Choices and Risks of Degenerative Disease

• The exact contribution diet makes to each disease is hard to estimate– Many experts believe that diet accounts for

about a third of all cases of coronary heart disease

– The links between diet and cancer incidence are harder to pin down

• Some choices, such as avoiding tobacco, are important to almost everyone’s health

• Other choices, such as those relating to diet, are more important for people who are genetically predisposed to certain diseases– Be aware of family medical history and own

blood work values

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Cardiovascular Diseases

• Worldwide, CVD accounts for more deaths among people of developed nations yearly than any other single cause

• Not just for men, as more women die of yearly of CVD than men; first time heart attacks for women more likely to be fatal

• Atherosclerosis– The most common form of cardiovascular

disease– Characterized by plaques along the inner

walls of the arteries

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Cardiovascular Disease

• No one is free of atherosclerosis– The question is how far

advanced it is and what you can do to retard or reverse it

– Usually begins with the accumulation of soft, fatty streaks along the inner walls of arteries, especially at branch points

– These gradually enlarge and become hardened fibrous plaques (lipids mixed with smooth muscle and calcium

• Plaques damage artery walls– Making them inelastic– Narrowing the passage

through them– Most people have well-

developed plaques by the time they reach age 30

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What causes plaque formation?• A diet high in saturated fat is a major

contributor to the development and progression of the disease

• Atherosclerosis-Damage may begin from a number of factors interacting with the cells that line the arteries and produce inflammation

•High LDL cholesterol•Hypertension•Toxins from cigarette smoking•Elevated blood levels of the amino acid

homocysteine-causes inflammation•Or some viral and bacterial infections

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• Normally, the arteries expand with each heartbeat to accommodate the pulses of blood that flow through them

– Arteries hardened and narrowed by plaques cannot expand

– So blood pressure rises– The increased pressure damages the

artery walls further and strains the heart• Because plaques are more likely to form at

damaged sites, the development of atherosclerosis becomes a self-accelerating process

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• As pressure builds up in an artery, the arterial wall may become weakened and balloon out, forming an aneurysm (brain, abdomen)– An aneurysm can burst

• In a major artery, such as the aorta, the leads to massive bleeding and death

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Cardiovascular Diseases• Abnormal blood clotting can also

threaten life– Arterial damage, plaques in the arteries,

and the inflammatory response favor the formation of blood clots•Platelets normally cause clots to form

when they encounter injuries in blood vessels

• In atherosclerosis, when platelets encounter hardened plaques, they respond to them as to an injury - clotting blood

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Cardiovascular Diseases• A clot may remain

attached to a plaque in an artery and grow until it shuts off the blood supply to the surrounding tissue– That tissue may die

slowly and be replaced by nonfunctional scar tissue

– The stationary clot is called a thrombus

-If it grows large enough to close off artery, called thrombosus

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Cardiovascular Diseases• A clot can break loose becoming an

embolus– Which travels along the system until it

reaches an artery too small to allow for its passage

– There the clot becomes stuck and is referred to as an embolism• The tissues fed by this artery will be robbed of

oxygen and nutrients and will die suddenly• Such a clot can lodge in an artery of the heart,

causing a heart attack, or lodge in an artery of the brain, causing a stroke

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Cardiovascular Diseases• Opposing the clot-forming actions of platelets

are active products of omega-3 fatty acids– A diet lacking in seafoods that contain these

essential fatty acids may contribute to clot formation

• Occasionally, heart attacks and stroke occur without apparent blockage and are due to a spasm of the artery

• Arterial spasms may be caused by:– Taking certain drugs, such as cocaine – Emotional stress – Exposure to cold – Cigarette smoking

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• Hypertension – Hypertension worsens atherosclerosis because a

stiffened artery, already strained by each pulse of blood surging through it, is stressed further by high internal pressure

• Injuries multiply, more plaques grow, and more weakened vessels become likely to burst and bleed

– Since hardened arteries cannot expand, the heart’s beat raises blood pressure

– Hardened arteries also fail to let blood flow freely through the kidneys, which control blood pressure

• The kidneys sense the reduced flow of blood and respond as if the blood pressure were too low

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Major Risk Factors for Heart DiseaseFactors which can be modified include:• Poor lipid profile (low HDL, High LDL, High TG)• High blood pressure• Diabetes• Obesity• Physical inactivity• Cigarette smoking• Atherogenic diet (too much saturated/trans fat and

too little fruits, vegetables, whole grains)

Factors that cannot be modified:Aging, male gender, family history of early heart

disease

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Risk Factors for CVD• Age, Gender, and Family History

– The increasing risk associated with growing older reflects the steady progression of atherosclerosis in most people as they age• Men: age becomes a significant risk factor for

heart disease at age 45 or older• Women: age becomes a significant risk factor

after age 55 when estrogen levels decrease

• Family history– Early heart disease in immediate family

members is a major risk factor

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Risk Factors for CVDHDL and LDL factors:

– LDL carry cholesterol to the cells• Including the cells that line the arteries where

it can build up as part of the plaques of atherosclerosis

– HDL carry cholesterol away from the cells to the liver for other uses and disposal• Elevated HDL indicates a reduced risk of

atherosclerosis and heart attack• With growing evidence that it may prevent

stroke as well– High LDL and low HDL correlate directly with

heart disease– Low LDL and high HDL correlate inversely with

risk

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Risk Factors for CVD

• How elevated LDL increases the risk of heart disease remains unclear– One mechanism may be through reducing

plaque stability• As LDL is incorporated into plaques, the

plaques weaken and become unstable• When this happens, they can rupture, causing

heart attack• In advanced atherosclerosis, a goal of

treatment is to lower LDL cholesterol to stabilize existing plaques while slowing the development of new ones

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• Hypertension– Chronic hypertension worsens CVD

• The higher the blood pressure above normal, the greater the risk of heart attack or stroke

• The relationship between hypertension and disease holds for

– Men and women– Young and old

• Hypertension injures the artery walls and accelerates plaque formation

– Initiating or worsening the progression of atherosclerosis

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• Diabetes– A major independent risk factor for all forms of

cardiovascular disease– In diabetes, atherosclerosis progresses rapidly

• Blocking blood vessels and diminishing circulation

– For many people with diabetes, the risk of a future heart attack is roughly equal to that of a person with a confirmed diagnosis of heart disease• 2x-4x as high as that of a person without

diabetes– When heart disease occurs in conjunction with

diabetes, the condition is likely to be severe

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• Obesity and Physical Inactivity– Obesity, especially central obesity, and physical

inactivity amplify a person’s risk of CVD• Elevates LDL cholesterol• Lowers HDL cholesterol• Worsens hypertension• Worsens diabetes

• Weight loss and physical activity– Lower LDL– Raise HDL– Improve insulin sensitivity– Lower blood pressure

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Risk Factors for CVD• Routine physical activity

– Strengthens all muscles, including heart– Improves the heart’s response to everyday

demands– Stimulates the development of new arteries

to nourish heart muscle– Favors lean over fat tissue– Only 30 minutes of light, balanced exercise,

performed at intervals throughout the day, can improve the odds against heart disease• An hour a day, as recommended by the DRI,

benefits the heart even more

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Risk Factors for CVD• Smoking

– Cigarette smoking is a powerful risk factor for heart disease and other forms of CVD

– Smoking damages the heart directly with toxins and burdens it by raising the blood pressure.

• Deprives the heart muscle of the oxygen it needs to maintain a steady beat

• Damages platelets– Making blood clots likely

• Toxins in cigarette smoke directly damage the lining of blood vessels making atherosclerosis more likely

• When people quit smoking the risk of heart disease begins to drop within a few months

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• A well-chosen diet often lowers the risk of CVD– Does so to a greater degree than might be

expected from its effects on blood lipids alone

– Factors that might take credit•Vitamins•Minerals•Antioxidant phytochemicals•Omega-3 fatty acids

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Diet to Reduce CVD Risk• Diet’s effects are felt in two opposing ways

– A diet high in saturated fat and trans fatty acids contributes to high blood LDL cholesterol (promotes plaque instability)

– Reducing those fats in the diet lowers blood LDL cholesterol and may reduce the rate of CVD

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Diet to Reduce CVD Risk• Controlling Dietary Lipids

– Lowering intakes of saturated fat and trans fat lowers blood LDL cholesterol and reduces heart disease risk• Other authorities recommend: no more than

30% of total calories from fat• DRI recommendations: the diet should contain

no more that 35% of total calories from fat

• Healthy people should limit cholesterol intake to 300 mg a day (one egg yolk has 200-250 mg cholesterol)– Although cholesterol plays a lesser role than

saturated fat and trans fatty acids, it still elevates blood cholesterol

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Diet to Reduce CVD Risk

• Strictly limiting all kinds of dietary fats is probably not necessary to maintain the health of the heart– As long as the diet is low in saturated fat

and trans fat, energy intake is controlled– The diet is ample in fish, fruit, vegetables,

and low fat milk products• It matters what people choose to eat

instead of saturated fats– Simple carbohydrates seem to elevate

blood triglycerides and reduce HDL cholesterol

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Fish oils:– Rich in omega-3

polyunsaturated fatty acids

– Lower triglycerides

– Prevent blood clots

– May reduce the sudden death associated with CVD

-Other rich sources of omega-3 fatty acids include: walnuts, flaxseed, high omega-3 fatty acid eggs, canola and soybean oil

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Diet to Reduce CVD Risk• Effects of Fiber, Nutrients, and Phytochemicals

– The soluble fiber of oats, barley, legumes, and pectin-rich fruits and vegetables helps to improve blood lipids

• These fibers bind cholesterol and bile in the intestine, reducing their absorption; 5-10 gms of soluble fiber decreases cholesterol levels by about 5%

– A high-fiber diet may reduce a blood marker of inflammation thought to indicate an elevated risk of having a heart attack (C reactive protein)

– Foods rich in viscous or soluble fiber provide antioxidants and helpful minerals to help protect against LDL oxidation

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Diet to Reduce CVD Risk• Alcohol

– Research on middle-aged and older people who drink one or two drinks a day with no binge drinking supports the idea that moderate consumption of alcohol will reduce their CVD risk• For this group, moderate alcohol consumption

has been reported to raise HDL cholesterol levels or reduce the risk of blood clots

• May also raise triglyceride levels

• Heavy alcohol use, more than three drinks a day:– Elevates blood pressure, damages heart

muscle, elevates risk of stroke

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Other Dietary FactorsSterol and stanol esters• Block absorption of cholesterol from the

intestine• Dropping blood cholesterol by about

7%-10%• The effect may be as powerful as some

medication in lowering blood LDL cholesterol

• Sterol and stanol esters reduce the absorption of some potentially beneficial phytochemicals

• Use may be best reserved for those who fail to lower their elevated cholesterol by other means

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• Diet and exercise form a powerful and safe combination for improving health

• Needed weight loss often reduces blood pressure

• So does eating a diet– Low in fat– Restricted in cholesterol– High in complex carbohydrates, whole

grains, fruits, and vegetables– Normalizes blood glucose

• More Strategies against CVD– Don’t smoke and relax

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Nutrition and Hypertension• Chronic high blood pressure

(hypertension) remains one of the most prevalent forms of CVD– Affecting almost one-third of the entire

U.S. adult population• For people age 65 or older, the lifetime risk of

developing it approaches 90%

– Contributes to half a million strokes and over a million heart attacks each year

– Especially threatening when paired with atherosclerosis

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Nutrition and Hypertension• Blood pressure-120/80• 120 - (systolic-highest pressure during contraction

of left ventricle) 80 - (diastolic-lowest arterial pressure during

relaxation or between beats)

• Ideal resting blood pressure is 120/80

• High blood pressure presents no symptoms you can feel-”Silent Killer”– A reading of 130/85 can be considered borderline

normal– Above this level the risks of heart attacks and

strokes rise in direct proportion to increasing blood pressure

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Role of kidneys in blood pressure control…

• For the kidneys to filter waste materials out of the blood and into the urine, blood pressure must be high enough to force the blood’s fluid out of the capillaries into the kidneys’ filtering networks

• If the blood pressure is too low, the kidneys act to increase it, sending hormones to constrict blood vessels and retain salt and water

• Atherosclerosis fools kidneys, which perceive the body is water deficient when it may not be

• The kidneys raise the blood pressure high enough to get the blood they need but too high for the arteries and heart to withstand long term

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How Does Blood Pressure Work in the Body…

• Risk factors that precipitate or aggravate hypertension: – Atherosclerosis-kidneys try to compensate

– Obesity (especially central obesity); for each 2.2 pounds of fat on your body, you add about 400 miles of additional blood vessels. These miles of blood vessel promote more vascular resistance which promotes higher blood pressure.

– Insulin resistance-increases obesity

– Age-Frequently occurs at 50-60 years of age

– Genetics-family history or African American race

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How Does Nutrition Affect Hypertension?• Nutrition factors for lowering blood pressure

– Lowering sodium intake– If overweight, lose weight; control fat intake– Using moderation with regard to alcohol– Increasing intakes of fruit, vegetables, fish,

and low-fat dairy products– Calcium, potassium, magnesium, and other

nutrients seem to play roles

• Translates to:– Control weight– Consume a nutritious diet– Exercise regularly – Control alcohol intake– Hold sodium intake to prescribed levels

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How Does Nutrition Affect Hypertension?

• DASH (Dietary Approaches to Stop Hypertension)– Recommends significant

increases in fruit and vegetable intakes

– Provides 30% of its calories from fat

– Emphasizes legumes over red meats

– Restricts sodium– Meets other

recommendations of the Dietary Guidelines for Americans

DASH plan consistently improves blood pressure

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How Does Nutrition Affect Hypertension?• Weight Control and Physical Activity

– For people who are overweight and hypertensive, a weight loss of as little as 10 pounds can significantly lower blood pressure

– Those who are taking medication to control their blood pressure can often cut down on their doses if they lose weight

• Moderate physical activity (walking, jogging) – Helps in weight loss– Redistributes body water– Changes the hormonal climate in which the body

does its work• By reducing stress, physical activity reduces

the secretion of stress hormones• This lowers blood pressure

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How Does Nutrition Affect Hypertension?• Salt, Sodium, and Blood Pressure

– A high dietary intake of salt and sodium is associated with hypertension

– The benefit of reducing salt intake in the treatment of hypertension is unquestionable

• Reducing sodium and salt may also prevent hypertension in healthy people– People who consistently consume diets low in

sodium have lower blood pressure than people with higher intakes

– Recommendation: everyone should moderately restrict salt and sodium intake to a level not exceeding the DRI committee’s UL

• No more than 2,300 mg of sodium per day

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• Alcohol– In moderate doses, alcohol initially relaxes

the peripheral arteries and so reduces blood pressure•High doses raise blood pressure

– Hypertension is common among people with alcoholism• Is apparently caused directly by the alcohol

• Alcohol may cause strokes– Even without hypertension

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Calcium, Potassium, Magnesium, and Vitamin C

– Increasing calcium often reduces blood pressure in both healthy people and those with hypertension

– Diets low in potassium are often associated with hypertension and high potassium diets seem to prevent and correct hypertension

– Magnesium deficiency causes the walls of arteries and capillaries to constrict and so may raise blood pressure

– Consuming a diet adequate in vitamin C seems to help normalize blood pressure

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How Does Nutrition Affect Hypertension?• To get all of the nutrients needed to keep

blood pressure low– Consume a low-fat diet with abundant fruits,

vegetables, and low-fat dairy products that provide the needed nutrients while holding sodium intake in bounds

– DASH diet• Reduces blood pressure• May lower blood cholesterol

• Should diet and exercise fail to reduce blood pressure, drugs such as diuretics or other medications may be prescribed– Diuretics work by increasing fluid loss in the urine

which also increases potassium excretion- Need to consume extra potassium rich foods

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Nutrition and Cancer• Cancer ranks second only to heart disease as

a leading cause of death and disability in the U.S.

• Inherited tendencies exert only a modest effect on most people’s risk of cancer development– Very few rare cancers are known to be caused by genetic

inheritance alone

• 20%-50% of total cancers are influenced by diet (Dietary fat, alcohol, excess calories, and low intakes of fruits and vegetables have been implicated in research studies)

• Most often lifestyle and environmental factors come into play in the development of cancer (smoking, diet, obesity)

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Nutrition and CancerPhysical activity and cancer:

• Restricting energy intake seems to limit cancer

• Physical activity that can balance energy intake may lower risk of developing cancer

• People whose lifestyles include regular, vigorous physical activity have the lowest risk of colon cancer

• Physical activity may also protect against breast cancer by reducing body weight and by other mechanisms

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How Does Cancer Develop?• Cancer is really a disease of the genes

– Cancer begins with one healthy cell whose genetic material sustains damage from a carcinogen such as a free-radical compound, radiation or other influence

• Damage to a cell’s DNA occurs every day– But most of the damage is quickly repaired– Sometimes DNA collects bits of damage here and there

over time– If the damage cannot be repaired the cell may self destruct

• Occasionally, a damaged cell loses its ability to self destruct also loses the ability to stop reproducing;

at this point millions of cancer cells form a tumorwhich can be life threatening if it takes over a healthy organ

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How Does Cancer Develop?

Cancer develops through the following steps1) Exposure to a carcinogen2) Entry of the carcinogen into a cell3) Initiation of a cancer as the carcinogen

damages or changes the cell’s genetic material (Carcinogenesis)

4) Acceleration by other carcinogens, called promoters, so that the cell begins to multiply out of control - tumor formation

5) Often, spreading of cancer cells via blood and lymph (metastasis)

6) Disruption of normal body functions

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Exposure Initiation Promoters Cancerous tumor

entry of by carcinogen enhance releases cells into

carcinogen that damages tumor the bloodstream

cell DNA development

Other carcinogens

(Some compounds in foods may stop the process of feeding the malignancy)

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Researchers think steps 1-4 are key to prevention

1) Exposure to a carcinogen2) Entry of the carcinogen into a cell3) Initiation of a cancer as the carcinogen

damages or changes the cell’s genetic material (Carcinogenesis)

4) Acceleration by other carcinogens, called promoters, so that the cell begins to multiply out of control - tumor formation

5) Often, spreading of cancer cells via blood and lymph (metastasis)

6) Disruption of normal body functions

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Which Dietary Factors Most Influence A Person’s Risk…

• Under study for possible effects regarding cancer are

– Excess calories-cancer rates increase– Diets high in certain fats– Daily use of alcohol– Vitamins and minerals in foods– Diets in which meat plays a dominant

role

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• In studies of human beings evidence is mixed as to whether a diet high in fat promotes cancer

– World population data reveal that high-fat diets often correlate with high cancer rates

• Studying the effects of high fat intakes in complicated

– Because fat is extremely calorie dense– Researchers must untangle the effects of

fat alone from those of the energy content of the diet

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• The type of fat in the diet may be important

– Some evidence implicates omega-6 polyunsaturated fatty acids in cancer promotion

– Some evidence suggests that omega-3 fatty acids from fish may protect against some cancers and may support recovery during treatment for cancer

• Moderation in fat intake and inclusion of several fish meals a week remain sound principles

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• Alcohol-Cancers of the head, neck, breast correlate strongly with alcohol intake

• Smoked, Grilled, and Well-Done Meats-Chemical reactions during browning of meat at high temperatures form known carcinogens

• Acrylamide (French fries) -Produced when carbohydrate rich foods are

cooked at high temperatures

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• Fiber – Epidemiological studies often report links

between eating plenty of fruits and vegetables and a low incidence of many cancers

– Fiber rich foods are source of phytochemicals• A prominent theory is that a fiber-rich diet

may protect against some cancers by: – increasing stool weight and diluting the colon’s

contents – stimulating bacterial fermentation which

nourishes colon cells– and speeding up the transit time of materials

through the colon thus minimizing exposure of the colon walls to cancer-causing substances in the feces

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• Fluids and cancer– Men who drink about 10 cups of fluid a

day have been reported to develop substantially less bladder cancer than those drinking only about half this amount

– A greater fluid intake dilutes the carcinogens that naturally form in urine and causes more frequent urination

– Plain water seems most beneficial

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• Folate and Other Vitamins– Folate deficiency seems to make cancers

of the cervix and colon more likely• Up to 10% of the U.S. population, and a much larger

percentage of people with low incomes, consume a diet low enough in folate to cause breaks in DNA that make cancer likely to develop

• Vitamin A– Regulates aspects of cell division and

communication that go awry in cancer– Helps to maintain the immune system

• Immune system cells can often identify cancerous cells and destroy them before cancer can develop

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• Vitamin D and exposure to sunshine have long been suggested as protective against cancers

– Other than skin cancer– The relationship is not clearly defined

• Calcium and Other Minerals– Laboratory evidence suggests that a

high-calcium diet may help to prevent colon cancer• Supplemental calcium seems to suppress

changes in the lining of the colon associated with the onset of cancerous changes

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• A recent review revealed that the majority of studies since 1990 confirm an association between colon cancer and both increased dietary iron intake and high body iron stores

• Iron is a powerful oxidizing substance -Oxidation may damage cell DNA to initiate

cancer-Whether iron increases a person’s risk for

colon cancer may depend on inherited tendency to store too much iron, degree of iron intake

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Foods with phytochemicals and cancer• Whole foods and whole diets composed of them,

not single nutrients, may be most influential on cancer development

-The phytochemicals in some fruits and vegetables are thought to be anticarcinogens

-Some phytochemicals for fighting cancer include lycopene (tomato based foods and watermelon) and ellagic acid (blueberries)

-Phytochemicals in foods interfere with cancer cell progression at all stages of development

• Phytochemical rich foods called functional foods

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Foods with phytochemicals and cancer

-A low intake of fruits and vegetables may leave cells unprotected against DNA damage in the initiation of many cancers

-Infrequent use of cruciferous vegetables - broccoli, brussels sprouts, cabbage, cauliflower, turnips, and the like - is common in colon and breast cancer cases

-Incidence of stomach cancer correlates with too few vegetables in the diet

• In one study, with vegetables in general

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Controversy: The Obesity Epidemic How Can We Gain Control?

• 97 million obese people– Are at increased risk

of serious illnesses associated with obesity (heart disease, arthritis, cancer)

• $60 billion spent on obesity-related health care

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The Obesity Epidemic - How Can We Gain Control?

• Why Has Our Society become Obesity-Prone?– Today, many people regularly overeat

large portions of inexpensive high-calorie foods-500 more calories than in 1970

– Changes in how leisure time spent– Limited physical activity– Lends itself to weight gain and poor sleep– May worsen with high calorie or caffeine

drinks/foods to promote more energy– and other inappropriate supplements,

alcohol, tobacco, or other drugs

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• Changing Physical Activity– Technological advances have relieved

people of many physical labor saving activities that would have expended calories in the past

• Changing Home Life– Changes in the family structure (more

time in work force, less meals at home)– The diet has changed more over the past

40 years than in any other comparable period of human existence

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• Food Advertising– The food industry spends more than $33 billion each

year on advertising which often promotes less healthy options

• The “Buy More” Strategy– Appeals to economic sense-”supersizing”– Larger food packages at retail level may prompt

cooking larger portions

• Portion sizes and obesity rates have increased proportionately over the years

• Marketing to Children-billions spent to markethigh calorie snack foods and beverages

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• Nutrition Education – Part of the blame for unheeded dietary

advice is placed on inadequate education in today’s schools

– A law passed in 1977 mandates that federal funds be supplied to states for training teachers to teach nutrition, but sufficient funds not always made available

– Some schools have set an example for healthier eating by removing soda pop machines

– Some school districts have decreased physical education requirements

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• Consumers can choose to live a lifestyle that can promote health and decrease obesity– Turn off the television and take up a physically

active recreation– Park farther away than usual and walk through the

parking lot– Seek out and use stairways instead of elevators– Obtain an inexpensive pedometer and vow to walk

10,000 steps each day– Watch portion sizes, eat out less often– Save enticing fatty and sugary fast foods and

snacks for special occasions– Teach the children in our lives to think differently

about food

Diet and Health. 2 Introduction 2 main kinds of diseases afflict people worldwide: Infectious...

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