Transcript Document 7298125

Judith E. Brown
www.cengage.com/nutrition/brown
The Inside Story
about Nutrition and Health
Unit 2
Prof. Albia Dugger • Miami-Dade College
Nutrition and Overall Health
• The health and fitness of the human body
depend on a variety of interrelated factors:
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Genetic traits
Environmental factors
Lifestyle factors
Health care
Diet
Conditions that Contribute to Death
Nutritional State of the Nation
• Nutritional deficiency diseases such as rickets
and pellagra were once common
Nutritional State of the Nation
• Today, life-style related chronic diseases are
the major causes of death:
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Heart diseases
Cancers
Diabetes
Stroke
Alzheimer’s disease
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
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”
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
Leading Causes of Death in US
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
Key Terms
• Osteoporosis
• Condition in which bones become fragile and
susceptible to fracture due to a loss of calcium
and other minerals
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
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
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
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
Diseases/Disorders Linked to Diet
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
Foods, Inflammation,
and Oxidative Stress
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
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
All-American Food Choices
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
Hunter-Gatherers
Food Then… and Now
Our Bodies Haven’t Changed
• Survival mechanisms for early humans:
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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
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
Typical Japanese Foods
Japanese Men: Diet and Diabetes
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
Improving the American Diet
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
MyPyramid.gov
Tracking the American Diet