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Truth about Fad Diets. Obesity, Health and the Student. Goals. Determine how to assess obesity and additional medical problems caused by excess weight. Understand how to read a food label. Identify appropriate ways to incorporate healthy foods into your diet. US Adults. Half are overweight
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Truth about Fad Diets Obesity, Health and the Student
Goals • Determine how to assess obesity and additional medical problems caused by excess weight. • Understand how to read a food label. • Identify appropriate ways to incorporate healthy foods into your diet.
US Adults • Half are overweight • One-fourth are obese Men Women African A. 56.5% 65.8% Mexican A. 63.9% 65.9% Caucasian A. 61% 49.2% Direct medical cost >$51 billion/yr for weight-related diseases
Dollars and Sense • U.S. spends 33 billion annually on wt loss (6 million Americans morbidly obese) • Adults trying to lose weight: 35-40% women, 20-24% of men • 22% of this population get regular physical activity • 39.3 million work days lost/yr • 11% of youth (6-17 yrs) overweight
Health risk of excess weight • Heart disease, HTN, Hyperlipidemia • Cancer: colon, breast, endometrial, pancreas, prostate, uterine, cervical • Infertility • Varicose veins • Stroke • Snoring
And the list goes on… • Kidney stones • Osteoarthritis • Gout • Diabetes Mellitus
Components of body weight • Water 60-65% • Muscle, Bones, Organs • Adipose tissue • Protection of organs/nerves, insulation, preserves body heat, maintains body temp, & vitamin absorption • Women 20-25%, essential 12% • Men 12-15%, essential 4-7%
Assessment of obesity • Ideal Body Weight • Metropolitan Life Insurance Co. • Men: 106# for 5ft, 6# for each inch over • Women: 100# for 5ft, 5# for each inch over • Body Mass Index (Quetelet index) • Weight in kg/Height in m2 • Caution with: increased muscle mass, edema • Waist-Hip ratio • > 88cm women, > 102cm men for those with BMI <40
Ideal Body weight classifications • Underweight <100% • Ideal 100% • Overweight 110% • Obese 135% • Medically sig. 160% • Morbidly obese 200% • Super obese 225%
How to classify BMI • Underweight <18 • Normal 19-25 • Overweight 26-29 • Obesity 1 30-35 • Obesity 2 36-40 • Morbidly Obese >45.1
Gynoid type (pear) Thigh/buttocks Energy reserves Android type (apple) Waist/upper abdomen HTN, Insulin resistance, Heart disease Fat distribution
20% increase in wt increases risk for Type 2 DM, HTN, CAD, Lipid NHANES: Women BMI >28 had 2x risk for disability/mobility problems Nurses Health Study BMI 23-25 had a four-fold increase in Diabetes BMI >35 was associated with risk of 93.2% for Diabetes Recent studies
Etiology of Obesity • Long-term imbalance between Energy intake and Energy expenditure Must be closely related: 2% over needs (50 kcal/d) for someone who required 2500 kcal/d If over one year weight gain: 1.5 kg
Hormonal Factors determined genetically Satiety signals Feeding activity Number/size fat cells Resting metabolic rate Studies of twins/adoptees Evidence that a Genetic component accounted for 67% 540 Danish adoptees were found to correlate with the weight of biological parent Role of Heredity
Human vs. Animal • Animal model of obesity are characterized by one single gene • Ob/ob mouse • Genetic defect for coding the protein leptin • Leptin normally produced in fat cells in proportion to fat mass. • Binds to receptors in hypothalamus and causes a decrease in food intake and increase in thermogenesis • Few leptin deficient obese adults have been identified • Obese adult usually has a higher levels of leptin indicating they are resistant to the hormone • Trials are underway
Primarily CHO Brain uses solely Converts protein/fat into glucose Gluconeogenesis Healthy diet: CHO: 50-60% Pro: 15-20% Fat: 25-30% Body’s Fuel source
Carbohydrate 4 kcal/gm Protein 4 kcal/gm Fat 9 kcal/gm Alcohol 7 kcal/gm Calories
Attempts to lose the weight • Low fat diet • Body weight associated to fat intake • Tend to eat same amount of calories • Obese people tend to underreport their intake (30-47%) • Starvation diets • Break down muscle and fat • Tend to store more when begin to eat again
Obesity • Over 50 percent of Americans are overweight. • One in three adults is obese. Why? • Sedentary lifestyle • Poor food choices • Obsession with dieting • Lack of time
The U.S. Diet Industry Almost $40 billion per year industry, includes: • Diet books • Diet foods • Diet programs • Weight-loss gimmicks
1960 Drinking Man’s Diet Steak and Wine 1967 Dr. Stillman’s Diet 1972 Dr. Atkin’s Diet 1973 Richard Simmons Fitness Guru 1978 Scarsdale Diet 1979 Pritikin Diet 1980 Beverly Hills Diet 1981Cabbage Soup Diet 1988 Optifast Liquid Diet 1991 Protein Power 1991Fen Phen Diet Pill 1995 Enter the Zone 1997 Fen Phen pulled from market Do You Remember?
Enter the Zone Protein Power Sugar Busters! Dr. Atkin’s New Diet Revolution The Anti-Aging Zone The Cabbage Soup Diet Dr. Bob Arnot’s Revolutionary Weight Control Program
Fad diets: The Zone • Claim: Boost protein, cut carbs achieve peak athletic performance • Why you lose: very low calorie • Downfall: few carbs can cause fatigue, weakness in athlete and few fiber foods • Most useful tip: Choose low fat protein sources, Eat several meals/snacks per day
Fad diet: Sugar Busters • Claim: Break sugar starch habit and enjoy eggs, cheese, wine • Why you lose: Reduced total calorie, not CHO • Downfall: Deprivation can set up binge mentality, low in calcium and zinc • Digestive downside: constipation • Most useful tip: cut back on added sugar
Does it exclude major food groups Does it promote supplement or pill use Does it suggest to avoid any one certain food Tips for evaluating fad diets
How to Recognize a Fad Diet Is the author credible? Diets that advocate: • Magic or miracle foods • Rapid weight loss/quick fix • No exercise • Rigid menus, “good” vs. “bad” foods, specific food combinations • Recommendations based on a single study or studies published without a peer review • Sounds too good to be true
Fad Diet Alert! Steer clear of these claims: • Fast, easy weight loss • Breakthrough miracle • Banish fat • Secret formula, new discovery • Cure • Balances hormones • Enzymatic process
DIETS DON’T WORK50% of Americans Diet Annually • Average diet lasts 42 days • Only 5 -10 percent maintain a significant weight loss (= 10 percent or more of starting weight) • No scientific data from commercial programs • No scientific data from any diet-book programs • Some cause significant health problems Source: John Foreyt, Baylor College of Medicine
Dieter Beware: Current Fad Diets • Enter the Zone • Dr. Atkin’s Diet Revolution • Protein Power • Dr. Arnot’s Revolutionary Weight Control Program • Sugar Busters! • Eat 4 Your Blood Type
NO RESEARCH TO SUPPORT DIETS • All six diets reviewed: • Lack Research • Use testimonials • Base validity on opinions not facts • Lack any peer review
ENERGY 101 • Calories are supplied by: • Carbohydrates • Fat • Protein • Calories In > Calories Out = Weight Gain • Calories In < Calories Out = Weight Loss
CARBOHYDRATES • Carbohydrate Intake Glucose + Insulin = Energy • Extra glucose: • Glycogen stores • Fat stores
High Protein DietsCommon Claims • Lose weight quickly • Never be hungry • Carbohydrate intake creates: • Increased appetite • Addiction to sugar • High blood sugar • Insulin resistance • Increased body fat
INSULIN: A Closer Look • Insulin Resistance: The cells are resistant to absorbing insulin and glucose to use for energy so glucose must be stored as fat.
INSULIN: A Closer Look • Insulin Resistance: The cells are resistant to absorbing insulin and glucose to use for energy so glucose must be stored as fat. • High Protein Diet Theory: 75% of dieters are insulin resistant. A high carbohydrate intake leads to a dramatic surge of insulin. Because of insulin resistance, the glucose cannot be used for energy so it is stored as fat. Therefore carbohydrates make you FAT!
INSULIN: The Reality • 10-25% of dieters are insulin resistant • Most with insulin resistance are: • Obese • Sedentary (insulin receptor sites and glycogen stores are full. Glucose stored as fat.) • Treatment: • Increase activity and decrease weight. This will deplete glycogen stores and increase blood glucose absorption. Less insulin is needed.
High Protein DietsThe Inefficient Energy Machine • Protein breakdown = Energy + Nitrogen • Fat breakdown (no glucose) = Energy + Ketones • Increased fluid requirements • Increased electrolyte loss • Increased strain on kidneys and liver • Increased uric acid in blood (gout) • Ketosis
Ketosis: Dizziness Nausea Decreased appetite Dehydration Electrolyte Imbalance Lethargy Bad Breath: acetone evaporation in lungs Bone Loss: Calcium buffers changes in blood pH Ketones in Blood = Ketosis Acidic waste from fat breakdown in the absence of carbohydrate.
High Protein Diets: A Closer Look • Low in calories; 1200 or less • High in protein / low in carbohydrate • Low in vitamins, minerals, phytochemicals • High in saturated fat and cholesterol • Increased risk for: • Cardiovascular disease • Cancer • Osteoporosis
High Protein DietsCommon Claims • Lose weight quickly • Never be hungry • Carbohydrate intake creates: • Increased appetite • Addiction to sugar • High blood sugar • Insulin resistance • Increased body fat
Enter the Zone Protein Power Sugar Busters! Dr. Atkin’s New Diet Revolution The Anti-Aging Zone The Cabbage Soup Diet Dr. Bob Arnot’s Revolutionary Weight Control Program
Sugar Busters!H. Leighton Steward; Morrison C. Berthea, M.D.; Sam S. Andrews, M.D.; and Luis A. Balart, M.D. Premise: Sugar is toxic, causing the body to release insulin and store excess glucose as body fat. High glycemic index foods should be eliminated. Minimal fluids with meals so digestive juices are not diluted. (1200 kcal) Negative Health Implications: Kidney and liver damage, fatigue, weakness and irritability. Vitamin and mineral deficiency. Risk for heart disease.
Sugar Busters!H. Leighton Steward; Morrison C. Berthea, M.D.; Sam S. Andrews, M.D.; and Luis A. Balart, M.D. High Glycemic Index Foods: Carrots Potatoes Beets Pasta Bread (refined flour) Rice (white) Fruit (must be eaten by itself)
Enter the ZoneBarry Sears, Ph.D. Premise: “Zone”:A metabolic state wherethe mind isrelaxed and focused and the body is fluid andstrong. Follow rigid, obscure rules, such as eating in “macronutrient blocks” and limiting carbohydrates. Negative Health Implications: Nutrient deficiency, increased risk of coronary heart disease, high cholesterol.
Enter the ZoneBarry Sears, Ph.D. Claims: • Weight easy to lose on 40:30:30 plan • Carbohydrates make you fat because 75% of Americans are genetically defective and over produce insulin. We must achieve an insulin zone. • Diet lowers risk for disease by decreasing production of bad eicosanoids (hormones).
Protein PowerMichael Eades, M.D. and Mary Eades, M.D. Premise: Low in fiber, high in fat, claims human body has no physical need for carbohydrates; should be completely avoided. Success of diet is demonstrated by the sales and popularity of the book. Negative Health Implications: Increased risk for coronary heart disease, high cholesterol, nutrient deficiency.