The Inside Story about Nutrition and Health

1. The Inside Story about Nutrition and Health Unit 2

2. Nutrition and Overall Health • The health and fitness of the human body depend on a variety of interrelated factors: • Genetic traits • Environmental factors • Lifestyle factors • Health care • Diet

3. Conditions that Contribute to Death

4. Nutritional State of the Nation • Nutritional deficiency diseases such as rickets and pellagra were once common

5. Nutritional State of the Nation • Today, life-style related chronic diseases are the major causes of death: • Heart diseases • Cancers • Diabetes • Stroke • Alzheimer’s disease

6. Key Terms • Diabetes (diabetes mellitus) • Disease characterized by abnormal glucose utilization and elevated blood glucose levels • Type 1, type 2, and gestational diabetes • Hypertension (high blood pressure) • Blood pressure inside blood vessel walls, greater than 140/90 mmHg

7. Key Terms • Stroke (cerebral vascular accident) • Occurs when a blood vessel in the brain ruptures or becomes blocked, cutting off blood supply to a portion of the brain • Associated with “hardening of the arteries”

8. Key Terms • Alzheimer’s disease • Brain disease; most common form of dementia • Causes memory loss of recent events, and loss of more distant memories over 5-10 years • Eventually produces profound intellectual decline, dementia, and personal helplessness

9. Leading Causes of Death in US

10. Shared Dietary Risk Factors • Dietary risk factors for many diseases are associated with development of chronic inflammation and oxidative stress • Examples: • Heart disease, diabetes, Alzheimer’s disease, osteoporosis, cancer, other chronic diseases

11. Key Terms • Osteoporosis • Condition in which bones become fragile and susceptible to fracture due to a loss of calcium and other minerals

12. Key Terms • Inflammation • First response of the body’s immune system to infectious agents, toxins, or irritants • Biologically active substances promote oxidation and other reactions to counteract the infection, toxin, or irritant • Chronic inflammation • Low-grade inflammation lasting weeks to years • Damages lipids, cells, and tissues

13. Key Terms • Oxidative stress • Condition that occurs when cells are exposed to more oxidizing molecules (such as free radicals) than to antioxidant molecules that neutralize them • Over time oxidative stress causes damage to lipids, DNA, cells and tissues • Increases the risk of heart disease, type 2 diabetes, cancer, and other diseases

14. Key Terms • Free radicals (oxidizing agents) • Chemical substances (often oxygen-based) that are missing electrons, which makes them reactive and prone to oxidizing nearby molecules by stealing electrons from them • Can damage lipids, proteins, DNA, cells, and tissues by altering their chemical structures and functions

15. Key Terms • Antioxidants • Chemical substances that prevent or repair damage to cells caused by oxidizing agents such as pollutants, ozone, smoke, and reactive oxygen • Oxidation reactions are normal parts of cellular processes • Vitamins C and E, and certain phytochemicals function as antioxidants

16. Diseases/Disorders Linked to Diet

17. Chronic Inflammation and Oxidative Stress • Chronic inflammation and oxidative stress are sustained by irritants present in the body • Excess body fat • High intakes of saturated and trans fats • Damage can be reduced by: • Loss of excess body fat • Eating foods containing omega-3 fatty acids and antioxidants

18. Foods, Inflammation, and Oxidative Stress

19. Nutrient-Gene Interactions • Sulforaphane (in cabbages) inactivates a gene that encourages cancer development • About half of US population is genetically susceptible to cholesterol in the diet • Omega-3 fatty acids may lower risk of Alzheimer’s disease in genetically susceptible adults

20. The Importance of Food Choices • Americans tend to choose energy-dense, nutrient-poor foods, including processed foods that pose great risks to health • High in saturated fat, salt, sugar • Low in fiber, vegetables, fruits

21. All-American Food Choices

22. Diet and Diseases of Western Civilization • Chronic diseases prevalent in the US and other Western countries have roots in dietary changes over past centuries • 40,000 years ago: Humans survived by hunting and gathering, with periods of famine • Now: Foods are processed, gathering food is not strenuous, feasts are not followed by famine

23. Hunter-Gatherers

24. Food Then… and Now

25. Our Bodies Haven’t Changed • Survival mechanisms for early humans: • Stimulate hunger despite excess body fat stores • Conserve sodium • Preference for sweet foods • Digestive system works best with high fiber • Not adapted to Western diets

26. Changing Diets and Disease Rates • Disease rates change as countries adopt Western diets • Japanese have the longest life expectancy • When Japanese adopt a Western diet: • Life expectancy goes down • Heart disease and cancer rates go up

27. Typical Japanese Foods

28. Japanese Men: Diet and Diabetes

29. The Power of Prevention • High animal-fat diets and lifestyle behaviors that promote chronic disease can be avoided or changed • Currently, risk factors for heart disease such as obesity and diabetes are increasing

30. Improving the American Diet

31. What Should We Eat? • MyPyramid Food Guide • Lean meat, fish, and dried beans prepared without added fat • Vegetables without butter or margarine • Fruits with no added sugar • Milk products with no fat • Dark-green and orange-colored vegetables • Whole grains

32. MyPyramid.gov

33. Tracking the American Diet