Judith E. Brown

Prof. Albia Dugger • Miami-Dade College

www.cengage.com/nutrition/brown

Nutrition and Heart Disease

Unit 19

Diet and Heart Disease

• Diets high in saturated fat and trans fat are a major risk factor for heart disease

• Other risk factors can also be modified• Except age, sex, genetic tendencies

Declining Rates of Heart Disease

• In the US, deaths from heart disease have dropped since the 1950s• Lower cholesterol levels•Reduced smoking• Improved blood pressure• Advances in medical care

Declining Rates of Heart Disease

A Big Health Problem

• Heart disease still causes 1 of 4 deaths

Heart Disease

• Heart disease (coronary heart disease)•Disorder that results when circulation of blood to

parts of the heart is inadequate•Usually due to narrowing of arteries caused by

buildup of plaque, which causes atherosclerosis

Key Terms

• Plaque•Deposits of cholesterol, other fats, calcium, and

cell minerals in the lining of the inner wall of arteries

• Atherosclerosis• “Hardening of the arteries” due to plaque buildup

Atherosclerosis

Heart Disease

• Narrowing of arteries by 50% or more can cause chest pain (angina)

• A heart attack occurs when an artery leading to the heart is completely blocked

Heart Attack

• Blood flow to the base of the heart blocked by ruptured plaque deposit or blood clot

Other Effects

• Atherosclerosis can also block arteries in the legs, neck, brain, and other body parts

• Cardiovascular disease•Disorders related to plaque buildup in arteries of

the heart, brain, and other organs and tissues

What Causes Atherosclerosis?

• High blood cholesterol levels and chronic inflammation in the inner walls of arteries work together to increase atherosclerosis

Key Terms

• Chronic inflammation• Inflammation that lasts weeks to years

• Inflammation• First response of the body’s immune system to

infection or irritation• Triggers release of substances that promote

oxidation and other harmful reactions

Cholesterol and Heart Disease

• Generally, the higher the blood cholesterol level, the more plaque builds up

• Diets high in saturated fat and cholesterol raise blood cholesterol

• Trans fat raises cholesterol levels more than saturated fat

Cholesterol Levels and Deaths

HDL and LDL Cholesterol

• Cholesterol in blood is bound to proteins, forming lipoproteins

• HDL (high density lipoprotein) lowers blood cholesterol levels (“good cholesterol”)

• LDL (low density lipoprotein) raises blood cholesterol levels (“bad cholesterol”)

HDL and LDL Cholesterol

Understanding HDL and LDL

• High HDL protects against heart disease• >40 mg/dL in men; >50 mg/dL in women•Moves cholesterol from blood to liver

• High LDL increases risk of heart disease• Forms plaque in arteries

Triglycerides and Heart Disease

• Triglycerides in blood are attached to very-low-density lipoproteins (VLDL)

• High blood triglyceride levels increase risk of heart disease, metabolic syndrome, and type 2 diabetes

Genetics and Blood Cholesterol

• Genetic traits influence the way diet and exercise affect blood lipid levels

• Nutritional deprivation early in life can permanently modify functions of certain genes, such as those that affect HDL levels

Inflammation and Heart Disease

• LDL cholesterol can enter the endothelium of artery walls and cause chronic inflammation• Inflammation oxidizes LDL cholesterol, which

damages artery walls and forms plaque

• Endothelium• Layer of cells lining the inside of blood vessels

Inflammation and Heart Disease

• Antioxidants stop or repair effects of oxidation, and lower inflammation

• Antioxidants are found mainly in plant foods• Phytochemicals in fruits and vegetables• Vitamins C and E• Selenium and beta-carotene

Antioxidants

Who’s at Risk?

• High LDL cholesterol• Low HDL cholesterol• High saturated, trans

fat, cholesterol diet• Family history• Diet low in vegetables,

fruit, whole grain• Elevated inflammation

• High triglycerides• Hypertension• Smoking• Inactivity• Obesity• Diabetes• Age (men>45,

women>55)

How to Have a Heart Attack

Risks for Women

• Diabetes, obesity, high triglyceride levels, and age are stronger risk factors in women

• LDL cholesterol levels are weaker predictors

• Risk increases after menopause

Managing Heart Disease

• Dietary and lifestyle changes:•Reduce high blood pressure and body weight•Reduce inflammation• Stop smoking• Improve blood lipid profiles• Improve overall health

Blood Lipid Levels

Diet and Blood Lipids

Diets That Lower Risk

Key Terms

• Plant stanols and sterols• Substances in corn, wheat, oats, rye, olives,

wood, and some other plants• Similar in structure to cholesterol but not

absorbed by the body•Decrease cholesterol absorption

Spreads with Stanols and Sterols

Other Factors

• Exercise and weight loss lower LDL-cholesterol and raise HDL-cholesterol

• Moderate alcohol consumption increases HDL-cholesterol

• Cholesterol-lowering drugs may be prescribed

Heart-Healthy Foods

• Current food recommendations for dietary treatment of heart disease

Heart-Healthy Foods

Chronic Inflammation and Oxidation

• EPA and DHA form anti-inflammatory chemicals

• Antioxidants, weight loss, and exercise also reduce inflammation

Statins

• Statins are drugs that reduce cholesterol production in the liver• Lipitor, Vytorin, Zetia, Crestor•Reduce heart attacks, strokes 30-40%

• Side effects•Muscle pain and weakness• Liver disease, kidney failure

Diet Alternative to Statins

Looking Toward the Future

• Escalating rates of child and adolescent obesity in the US will lead to a 5-16% increase in heart disease by 2035

• Changes are needed in diet and lifestyle, quality of foods in stores and restaurants, and consumer awareness