Week 10 Weight Loss Flashcards
WL Medication
- E/NE
- Serotonin:
> Phen-fen & Redux (damages heart valves) - Cannabinoid receptor:
> Block endogenous CB1 signals (N/A) - Orlistat (Xenical):
> inhibit fat digestion (lipase); and absorption in SI
> Sid effects: fat in feces, less absorption of FSV, involuntary projectile diarrhea
Bariatric Surgery (Types)
- Gastric Banding (Lap)
- Roux-en-Y: bypass surgery reducing stomach size and skips part of SI
> Possible CNS effect: curbs sugar cravings by eliminating sugar-induced dopamine release - Vertical Sleeve Gastrectomy (VSG)
- Gastric balloon
> Via mouth and endoscopy; saline-filled
> Takes up stomach space (temporary, needs removal after 6 months)
Changes in BMI:
Roux-en-Y > sleeve gastrectomy > intensive medical therapy
Bariatric Surgery Benefits and Risks
1. Benefits: > Restrict food consumption > Long-term weight loss > Favorable changes in gut hormones and microbiota (Reduce appetite/enhance satiety) 2. Risks: > Vitamin/mineral deficiencies > Surgical complications and re-hospitalization (induce DM remission within 5 years in 68% of obese adults, 1/3 relapsed) > Irreversible (Except for banding)
Dynamics and Statics of Fat Mass
Adipocyte = major determinant for fat mass
> Fat cell # stays constant in adulthood in lean/obese people even after marked WL
Hypothalamus
- Appetite and energy balance regulator (intake + expenditure)
- Feeding centers: lesions reduce food intake –> starvation to death
- Satiety center: lesions can increase food intake (lose sense of fullness) –> obesity/lethargy
GI Signals: Ghrelin and Leptin
- Induces food intake/appetite (stomach/upper GI tract) –> weight gain
> Obestatin: appetite suppressor (stomach/upper GI tract) - Adipocyte (fat stores)
> Appetite suppressor, increase glucagon, reduce adipose mass (rat), peptide hormone (Ob gene)
> Ob mutants are obese/T2DM: db/db defective in leptin receptor (Db)
Anorexia Nervosa
- 7 years
- 9% F, 0.3% M
Extreme Weight loss (17.5-) from self-enforced semi-starvation (less than 300-600 kcal/day)
> Distorted body, irrational fear of weight gain
> Anemia, amenorrhea, depression, osteoporosis
> 10% can die (heart ailments, infection, etc)
> UCSD Study: eating –> dopamine release, but anorexic subjects respond with anxiety, NOT pleasure
Binge Eating (3.5%F, 2%M, 8.1 years) vs Bulimia Nervosa (1.5%F, 0.5%M, 8.3 years)
- Non-stop eating beyond satiation 2x/week (chronic)
> 3000+ kcal during one binge - Binging episodes + purging (enema/laxatives)
> Acid from vomiting –> stomach ulcers/tooth decay/torn esophagus; Low K –> cardiac arrest
Diet vs Dieting
- Control/reduce energy intake
- Increased energy expenditure via physical exercise
- Implementation of life-long beneficial habits
- Altering processing degree
Foodborne Illness (FI) parasites, viruses, bacteria, and fungi/prions
50 mil cases/year, 128,000 hospitalizations/3000 deaths (1/2 kids 15-)
> Industrialization and centralization of food processing (MMWR)
> High risks: 5- kids, impaired immunity, pregnant women),
> Mostly from meat-poultry, vegetables and dairy-eggs
> Online illness reports complement traditional surveillance systems via real-time info (implicated foods, location, FI)
> Symptoms: GI tract distress (bloody diarrhea, cramp), hemolytic uremic syndrome (HUS) –> acute renal failure (damaged RBC clog kidney)
FI: E. Coli/Salmonella
- Symptoms:
> Severe GI distress + HUS
> Deadly strains produce toxins (Shiga-like) - Sources:
> Contaminated food with fecal material (raw) - Salmonella: greatest public health burden pathogen (2nd leading cause of food poisoning 11%, 1st death 28%/hospitalization 35%)
FI: Campylobacter and Listeria
- Toxins destroy epithelial lining of SI/LI –> diarrhea (uncooked meat, 90+%)
> 3rd total episodes (9%) and hospitalizations (15%) - 2nd Highest % of fatalities (10-20%)
> Recent: cantaloupes from CO (IC bacteria)
> Hardy: refrigerator growth and heat resistance (killed by pasteurization)
> Source: fecal-contaminated food (Deli meat, smoked seafood, raw milk)
Hepatitis A
RNA virus attacks liver (weeks-6 months)
> Easy transmission via food and water droplets
> Source: uncooked shellfish (oysters) near human sewage; raw veggies/fruits with infected handlers
Leading Pathogens
- Norovirus (58%):
> Gastroenteritis (pathogen); 1st total episodes, 2nd leading cause of hospitalizations, 3rd deaths cause
> Risk sources: nursing homes, restaurants, dorms and cruise ships
> Vessel Sanitation Program: 130,000/74 mil cruise passengers met acute GI illness criteria and only 1/10 are from norovirus outbreak
Antibiotic resistance threats: Superbugs
Resistant bacteria that cause pneumonia, urinary tract and skin infections
> 87% meat contaminated by enterococci (fecal)
> Ground turkey, pork chops, beef and chicken
> 2 mil illnesses and 23,000 deaths
> AMR estimated to be 10 mil in 2050, followed by CA (first case of E. coli infection resistant to colistin)
> 80% of Ab are used on farm animals
Allergies
Adverse responses by IS
> 6M children, 2M adults
> Anaphylaxis: systemic reaction (Can be fatal)
> 1st exposure: Many IgE Ab made –> attach to mast cells
> 2nd exposure: IgE-MC release granules and chemical mediators (histamine/cytokines) –> cascade of symptoms
> Peanuts (25%), milk (21%), shellfish (17%); nuts/legumes only has outgrowth chance of 10%/20%
Intolerance
NOT by IS responses; react to food component/indigestibility
> Requires greater quantity to trigger
> MSG: flavor enhancer/umami receptor activator (soy sauce, increases BP, numbness, vomit)
> Sulfites: antioxidants in preservatives (wines, salads, dried fruits; flushing, airway spasms, decreases BP)
> Lactose: no lactase to cleave in SI (normal for mammals to lose after weaning; better survival for 7500 y.a. Hungarians; 95% N. Euro descents; 15% White, 70% AA, and 90% E. Asians)
Environmental Toxins:
Lead, Salmonella, E. Coli, Botulism, Inorganic
> CA health alerts: 96.3% for imported candy products (34% Mexico, 24% CHina, 20% India)
CA: 1000 cases/year of children 5- with high blood Pb level (10+ug/dL)
Environmental Toxins: Bioaccumulation
- Bioaccumulation: concentration in food chain
> Magnification of dioxins (burnt plastic)
> Oakland Tribune-Commonweal Study: high levels of PBDE in children (flame retardants), 35 ppb in average adults (highest in CA), but family had 100+ (most in infant/younger) - Synergistic effects:
> Combo increases toxicity - Vulnerable populations: infants, elderly, pregnant (affects subsequent generations)
Human Toxome Study
90+% compounds
> PFOA (Perfluorooctanoic acid): carcinogen and liver toxin (nonstick coating, popcorn bags; pregnant women are 3x more likely to have overweight daughters)
> Phthalates: Neurotoxin (plasticizers; impaired neurodevelopment –> children aggression, ADD. depression
> PBDE (Polybrominated diphenyl ethers): teratogen, neuro and liver toxin (fire retardants)
> Bisphenol A (BPA): endocrine disruptor (canned foods, ATM receipts, banned in EU/Canada; CVD, HTN, behavior issues)
Plastic Galore
1. Safe: > PET/PETE: polyethylene terephthalate > HDPE, LDPE, PP 2. Caution: > V/PVC: polyvinyl chloride > PS: polystyrene > Polycarbonate/BPA
Coffee and Caffeine
Highest intake in Netherlands
> Association with cause-specific mortality
> Caffeine metabolic rate by cytochrome P450 enzyme and CYP1A2 (1A fast and 1F slow; slow metabolizers have higher risk of disease)
> CYP1A2 modifies association between coffee intake and HTN risk: when you have 1A/1F or 1F/1F, the hazard ratio is higher the more coffee you drink
Individual Variation and Personalized Nutrition
People eating identical meals –> high variability in post-meal BG response
> 46,898 PPGRs to meals in population cohort of 800 participants: algorithm integrating clinical and microbiome features can predict personalized PPGR/glycemic responses to complex meals
Colon Microbiota
Colonize mucus layer of gut
> fiber fermentation by-products nourish cells lining the colon, calibrate IS (prevent asthma, Crohn’s)
> Regular dietary fiber intake prevents erosion of gut mucus microbial barrier
> Increased total body fat mass + obesity metabolic phenotypes are transmissible with uncultured fecal communities
> Protects from celiac at birth
