Anthrobio Notes Exam 2 - study guide PDF

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2/14 Cultivation Continuum ● Foraging ● Horticulture ● Pastoralism ● Agriculture Agriculture ● Different from today → without machines ○ Physically demanding ● Terrace farming on hilly/mountainous ranges ● Why farm? ○ Jared Diamond, Guns, Germs, and Steel ○ Foraging more reliable, often takes less time ○ Early farmers often less well off than hunter-gatherers ○ So why switch? ■ Forager population density getting too large ■ Megafauna extinct? ● Around time modern humans showed up some larger species seemed to disappear → maybe we ate up larger packages of food and there wasn’t as much to eat ■ Late Pleistocene: warming trend ● Global warming ● Interstadial it got warmer and wetter ● SW Asia: Natufians around 14,700 years ago ○ Foragers with plenty to eat, settled villages ■ Unlike foragers ○ Cereals, legumes, nuts/fruit, gazelle, deer, wild goats/sheep ○ Grinding stones, sickles, arrowheads ● Then Younger Dryas began (12,800 years ago) ○ Back to cold for many generations ○ Some Natufians returned to mobile lifestyle ○ Others remained settled, intensified agriculture ● By ~12,000 years ago, behavioral changes ○ Beginning of Holocene: ice has receded ○ Warmer, more stable climate ○ Potential population pressure as environment stabilized ■ Harder to still forage ○ Within 2,000 years, domesticated plants, then animals ● Plant domestication: SW Asia, China, Mesoamerica, Andes, SE U.S., sub-Saharan Africa, highlands of New Guinea ● Levant (SW Asia) founder crops ○ Emmer wheat

○ Einkorn wheat ○ Barley ○ Rye (later) ○ Lentil ○ Pea ○ Chickpea ○ Flax ● Multiple founder crops around the world ○ Maize, beans, squash, yams, potato, quinoa, millet, sorghum, rice ○ Foods that grow as grasses → grains ● Artificial selection ○ Domesticated bananas bigger, don’t have seeds ● Hulled vs. free threshing wheat ○ Hulled ■ Einkorn ■ Emmer ■ Spelt ○ Free threshing ■ Durum (pasta) ■ Common (bread) Animal Domestication ● Clutton-Brock: domestic animals have been bred in captivity for human economic profits and humans totally control the breeding, food supply, and organization of territory ● First animals ○ Sheeps, goats, cattle, pigs, horses ○ See map ● Less common ○ Llama, camels, donkey, water buffalo, yak, bali cattle, mithan, reindeer ● Domesticates ○ Docile (or selectable) ○ Non-territorial ○ Uninhibited breeding ○ Dominance hierarchy (human as alpha) ○ Fast ontogeny ■ Grow up faster ○ More tender meat, higher fat ● Domesticated vs. not ○ Sheep and goats (domesticated) ■ Group size 10-20 ■ Hierarchies ■ Short flight distance ■ Adaptable to diet, environment ○ Ibex, oryx, and gazelle (not)

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■ Group size 9-45 ■ Non-hierarchical ■ Long flight distance ■ Less tolerant of environment, diet Earliest domesticated animal: the dog ○ ~12 Ka (genetic data) Common characteristics (of domesticated animals) ○ More variable coats (star on forehead, white forelegs) ○ Paedomorphosis (adult looks like child) ■ Juvenile traits retained in adult ■ Shorter snout, broader skull ■ Juvenile behaviors ■ Chimp has more shape change from fetus → adult than humans ● Humans self-domesticated? ○ Our brains are smaller than brains of first modern humans and Neanderthals ○ Faster maturation ○ Smaller brains ○ Smaller bones ○ tame/docile Phenotypic changes ○ Belyaev fox experiment ■ Selected foxes, chose ones more comfortable with humans, new generation was more playful and tame, different fur (black and white) ■ White spotting, curly tails, droopy ears

Health Consequences of Farming ● Has there been enough time to adapt to new diets? ○ Grains and salivary amylase ■ More wheat, other cereals → more starch digestion ■ Enzyme: salivary amylase ○ AMY1 copy number variation and diet ■ Lower starch diet parts of the world → less of the gene ■ People have adapted to consuming more starch ○ Lactase and amylase → milk and starch consumption not completely independent ● Alcohol shows up shortly after cultivation ○ China 7000-6600 Ka ● Perils of farming ○ Reduced dietary diversity ■ At risks if crops fail, reduces nutritional diversity ○ Deficiencies of specific nutrients ○ Refining for storage worsens problems

Farmers less healthy than ancestors ■ Enamel hypoplasia, caries, harris lines (bone growth stopped for a while) ■ Cavities ○ Malocclusions and dental crowding ■ Cooking reduced stress we placed on jaws ■ Jaw bones not growing big enough to hold all our teeth Possible contributors to shift to farming include: ○ More calories/day/person ○ Shorter IBI (more calories, weaning foods) ○ Labor force ■ More kids ■ Increase in population ○ Changes to local ecology ○

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Ötzi the Iceman (~5300 Ka) ● Melted out of glacier in Austria, 1991 ● Adult male (40s): lactose intolerant, arthritis, tooth decay, heart disease ● Arrow shot into back, brain bleed ● Found with clothing, tools ● 61 tattoos ● Stomach contents: grain, meat ○ Red deer, ibex meat ○ Einkorn wheat ○ Teeth worn down–gritty diet ● 13C, 15N isotopes ○ Ate a lot of meat

2/19 A brief world tour of “traditional” foods ● With caveats in mind ● Look at what is the same about all of them ● Africa ○ W and C: fufu (cassava/yuca/manios), plantain, yams ○ S: ugali (maize) ● Polynesia ● North America ○ Maize, beans, squash ■ Grow together in nature ■ Planted together → complementary nutrients that they take in from the soil and put back into it ● Asia ● Middle East

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Key points ○ People eat what grows well in the places they live ○ Things that were first domesticates in part of the world tends to be what they still eat ○ All of them have a lot of carbs → rapidly metabolized ■ Reliable source of starch ■ Poi, fufu, ugali, porridge, rice… ■ Easy to digest, starts with salivary amylase in the mouth → broken up into glucose ○ High diversity ○ Traditional diets not associated with metabolic disease ■ Obesity ■ High bad cholesterol ■ High blood pressure ■ Type 2 diabetes ■ Heart disease ○ How do these diets vary from stereotypical American diet?

What’s so bad about the SAD? ● Standard American Diet ○ Very processed ○ Artificial preservatives and colors ○ Changed a lot from the way they came out of the ground ● High in refined and processed foods (flour, sugar), red meat (sat fat, nitrates), fats and oils ● High calorie, high energy density, low fiber ● More energy-dense foods = lower volume ○ Comparing 1575 kcal ○ Can eat a lot more of lower energy density foods ○ Might not feel as full with high energy density → less food ● What 2,000 calories looks like photo essay ○ Fat makes people feel more full Amount of ultra-processed foods and added sugars in U.S. diets ● Unprocessed foods: 30% of calories ● Processed ingredients: 3% of calories ○ Might mean ingredient person is adding to food themselves ● Processed foods: 9% of calories ● Ultra-processed foods: 58% of calories ● % of energy from ultra-processed foods and % of energy from added sugars increase together Ultra-processed foods in France ● Association b/w ultra-processed foods and risk of mortality ● Ultra-processed foods ~30% of calories

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Each +10% increase in ultrapocessed foods increased risk of death +14%

Changes in grocery spending 1982-2012 ● More processed foods ● Less meats ● Increase fruits and veggies ● But what people are SPENDING in dollars not volume Pollan: biggest problem is ● All of the above How did we get here? History of food policy in U.S. ● Correlation b/w increase in autism and organic food sales is .9971 ○ Organic food does not cause autism! ○ Correlation does not mean causation ○ Hypotheses must be tested ● 20th C: multiple factors changing at once ○ Better medical care (less disease, longer life) ○ Type of food ○ Amount of food ○ Activity levels/workload ● Causes of mortality ○ In 1900 heart disease was 4th leading cause ○ 2010 heart disease is number 1 and diabetes 7 ○ People not dying of influenza, tuberculosis, diarrhea/GI infections ○ More health care now, but still a lot of death ○ Increase in more attributions of death to cancer could be because they’re living long enough to develop it ● 19th century: most Americans ate primarily local foods ○ 1850: 60% Americans worked in agriculture, people grew, raised, hunted food ○ Smoking, drying, salting, pickling ○ Canning invented 1810 but not widely used til Civil war ○ Local markets ○ Root cellars ● World Wars continued development of food tech ○ 1900: 41% agriculture, 1945: 16% in agriculture ○ Shift from agriculture to industry continued ○ Scientific approaches to nutrition ● New technology to feed troops ○ Emphasis on science of food and nutrition ○ Should listen to scientists ● Nutrition advice based on scientific approach ○ Carbs and fats: energy foods ○ Protein: Bodybuilding

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○ Protective foods: vitamins 1950s-60s: convenience foods ○ People wanted to spend less time on cooking ○ More women in the workplace ○ Don’t need to make everything from scratch 1953: Swanson’s TV Brand Frozen Dinner ○ I’m late but dinner won’t be 1970s: food prices spike ○ Nixon asks AG Sec Earl Butz to help ○ Change from supporting farmers (stockpiling) to boosting commodity crops (corn, soy) ○ Too much of a good thing: prices plummeted ○ Wave of consolidation Fewer, larger farms ○ Subsidies of family farms More monoculture and fertilizer ○ Need to ensure that they grow, can rotate crops around in a complementary way to help the soil Corn and soy overtake wheat Where does soy end up? ○ Soy and soybean oil: ■ Vegetable oil ■ Salad dressing/mayo ■ Margarine ■ Protein filler ■ Meat alternatives ○ Taco bell meat: lawsuit claimed not beef ■ Amount of soy in taco bell meat caused the meat to no longer meat federal definition ■ Soy lecithin = fatty emulsifier ● Keeps food together ■ Maltodextrin = starch (filler, can be sweet) ■ Oats = filler (here, mixed with wheat) ■ Yeast = natural monosodium glutamate (MSG) Where does corn end up? ○ Corn and corn oil: ■ Vegetable oil ■ High fructose corn syrup (soda) ■ Cows (feedlots) ■ More recently, ethanol ○ Beef cattle often finished on corn ■ Spend first part of life grazing, around time when they’re gonna get slaughtered, fed corn for several weeks

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■ Increases the fat content of the meat Sugar consumption trend ○ 1850 sugar consumption spiked and has continued to ■ Dip during World Wars ○ Now 10x sugar consumption of people in 1700s ○ Obesity prevalence has also increased ■ Correlated, don’t know if one causes other ○ 120 lbs / person / year ■ 10 pounds a month HFCS in many foods including soda ○ Going up in recent years, sucrose going down Animal production consolidating too ○ Fewer farms → many more animals ○ Mega farms Trends in carnivory ○ Less red meat, much more chicken ○ Beef as health risk (recalls, mad cow, heart disease) ○ Chicken faster to cook?

2/21 (Cont.) Concerns about Saturated Fats ● Milestones in diet, fat, and obesity ○ 1953: Ancel Keys proposes lipid hypothesis ■ Sat fat intake → serum (blood) cholesterol → heart disease ■ Cholesterol comes from animal food ○ 1976-77: Sen. George McGovern’s hearings on “Diet and Killer Diseases” conclude fat is unhealthy ○ 1978: High fructose corn syrup hits the market ○ 1980: Obesity begins to increase more rapidly ● Before: Ads about lard and meat ● After: more low fat products ○ Snackwell’s phenomenon ■ Fat free cookie ■ High in carbohydrates (sugar), relies on gums to hold together ○ Trans fats thought to be healthier ● U.S. consumption of fats and oils ○ Total +20% per person from 1980-1999 ○ Despite desire for low fat food ● New health concerns ○ Trans fat raises bad cholesterol, lowers good ○ Despite low fat advice people kept getting bigger ● Food manufacturers can round down ○ Hydrogenated fats

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○ Less than half a gram, can round to zero Lipids in veggie oils differ ○ >50% mono/polyunsaturated ■ Olive, canola, soybean, corn ○ >50% saturated fatty acids ■ Palm, palm kernel, coconut ● Palm and palm kernel ○ ~50% saturated ○ Replacement for trans fats ○ Keep things together ● Palm plantations in Indonesia ○ Pressure on orangutan habitats ○ Palms grow there ● Some manufacturers report where they get their palm oil Modern U.S. diet ○ Wheat, corn, soy, potato ○ Vegetable oil (baking, fried) ○ Highly refined (flour) ○ convenience/packaged foods ○ Chicken, beef, pork, dairy ○ “5 a day” for fruit and veg, few do it Positive trends ○ CSAs ○ Local food movements ○ Uptick in farming

Obesity Focus is not individuals, but populations ● Each person affected by a lot of different factors Population level change 1985-2010 ● CDC definition: Epidemic refers to an increase, often sudden, in the number of cases of a disease above what is normally expected in that population in that area ● Insane increase in obesity by states ● Similar increase worldwide 1975-2016 What is Fat? ● Fat (adipose) stored throughout the body ○ 1) white fat ■ Subcutaneous ■ Visceral ■ Intramuscular ■ Liver

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○ 2) bone marrow fat ○ 3) brown fat White fat ○ Essential, need to live ○ Lipid bilayer of cell membrane ○ Myelin sheath around nerve fibers in brain ○ Stores vitamins A, D, E, K ○ Cholesterol: sex steroids, other hormones ○ Insulates body, cushions organs ○ Stores energy: adipose tissue or adipocytes ○ What's in a white fat cell? ■ A large lipid droplet, mostly triglycerides ■ Roughly 1 billion adipocytes per lb of fat ■ Number does not decrease but can increase ○ Subcutaneous white fat ■ Below the skin ■ Cellulite, liposuction ■ Less harmful metabolically ■ Cushion, passive insulation ○ Visceral white fat ■ Around the viscera (organs) inside body wall ■ More harmful metabolically ○ Metabolic differences ■ Subcutaneous WAT secretes leptin, adiponectin ● Lower appetite, higher insulin sensitivity ● healthier ■ Visceral WAT secretes inflammatory cytokines ● Insulin resistance, heart disease ■ Heredity ■ hormones/inflammation ■ exercise/not ■ Repeat dieting? ● Can lead to accumulation of visceral fat ■ Estrogen major driver of hip and thigh fat ● In menopause, absence of estrogen → visceral fat ■ Testosterone lowers fat depots Bone marrow fat: not just for breakfast anymore ○ Fat cells (adipocytes) found in marrow ○ Nobody really knows what they do ○ Could be pathological, neutral, or adaptation ○ Red-yellow change with age is normal ■ Most marrow hematopoietic (“red”) at birth ■ Fat cells increase with age, most fatty (“yellow”) by 20

Marrow fat higher when bone mass is lower ■ Seen in osteoporosis, anorexia, disuse ■ Also in young, healthy subjects ■ Energy storage? Brown fat (BAT) uses energy to make heat ○ UCP-1 in mitochondria ○ Uncouples proton gradient ■ Uncoupling protein ○ Energy released as heat instead of ATP ○ Burns fat instead absorbing it ○ When a person goes from thermoneutral to cold, more brown fat cells taking up glucose ○ Gain heat but lose ATP production ■ Through the membrane w/o ATP synthase, energy released as heat ○ Could use as weight loss drug → brown fat to release fat ○

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Why does white fat accumulate? ● 3 ways to think about energy ○ Energy status ($ in bank account) ○ Energy balance (whether $ in = $ out) ○ Energy flux (rate of $ moving through account) ○ Positive energy balance leads to weight gain ● What determines where fat goes? ○ More calories in than out ○ Capacity in subcutaneous depots → fat goes there (under skin) ■ If already full, or if person is smoker or under high stress → greater accumulation in visceral obesity ● Other metabolic problems ○ No ectopic (outside of where it’s supposed to be) fat ■ Low muscle fat, low epicardial fat, low liver fat and normal function ■ Normal metabolic profile ■ Absence of clinical criteria for metabolic syndrome ○ Lipic overflow-ectopic fat ■ Inc muscle, epicardial fat, and liver fat ● Metabolic probs ○ Bathtub theory of fat deposition ■ Fat can’t be deposited in subcutaneous depots due to ● Genetics ● Smoking ● Stress response (cortisol) ● Inflammation ■ Result: ectopic fat deposition ○ Abnormal: liver

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■ Non-alcoholic fatty liver disease ■ Triglycerides accumulate in liver cells ■ Can impair liver function ■ Reversible ■ Same thing as foie gras (overfed duck liver) Abnormal: intramuscular lipid ■ Too much linked to insulin resistance ■ Exception: athletes have high IM lipid but not insulin resistance Sarcopenia & adipocyte infiltration common in aging ■ 21 year old vs. 63 year old thighs ● Older: more subcutaneous fat, muscle smaller and less dense, bone thinner, area of marrow looks bigger Intramuscular lipid tastes good tho

Body mass vs body composition ● BMI: weight for height ○ Kilograms of body mass per square meter of height ○ Kg/m^2 ○ Known issues/ problems ○ Biggest problem: no body composition ■ Can’t tell muscle from fat using BMI alone ■ DEXA, Bod Pod, etc. needed for accurate body comp 2/26 (Cont.) ● BMI does not show distribution of fat ○ Jim Bell in UK calls these TOFI, FOTI ■ Thin outside fat inside, fat outside thin inside ○ Metabolic obesity: normal BMI but high VAT ○ Higher risk for insulin resistance and T2D ○ Possible association with weight cycling ○ Can have variation in visceral fat content even if you have same waist circumference Debate: Is obesity always unhealthy? ● Concept of “fit fat” ○ A lot of subcutaneous fat but not a lot of visceral ● Discordant twin study ○ Looked at pairs of identical twins who were either concordant (similar body mass) or discordant for body fat ○ 8/16 discordant pairs had no diff in liver fat, relatively low visceral fat, were generally metabolically healthy ○ It’s possible to divide people with obesity to people who are metabolically healthy and those at risk

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Study by Bell says it’s a matter of time → didn’t track twins for long enough ■ Over 20 years people with unhealthy obesity increased

(New Lecture) Met Syndrome Insulin ● What is insulin? ○ Hormone made my beta cells in pancreas ○ Lets glucose enter cells ■ Every cell needs glucose coming in to make its own ATP ○ Without it, hyperglycemia (high blood sugar) ■ Glucose in blood stream ● Chronically trapped → diabetes ○ Regular person ■ Every time they eat blood glucose increases then insulin levels go up, glucose goes back down, insulin goes back down ● Insulin resistance ○ Fewer receptors ■ Receptors that work don’t work as well ○ Overproduction of insulin ○ Pancreas stressed, leading to Type 2 diabetes ● Glycemic index ○ Glycemic index: ranks carbs (0 to 100) on how much they raise blood sugar levels ○ Low GI foods require less insulin to metabolize ○ High GI foods require more ○ Low: non starchy vegetables, fruit ○ High: refined carbs, starchy veg ○ Minimal: protein and fat ● Glycemic load ○ GL = (GI x amount of carb) / 100 ○ Apple: GI of 40, 15 g carb, GL = (40x15)/100 = 6 ○ See examples ● Two different studies: blood glucose rise, higher rating after meal vary w GI ○ High GI meal has greater excursion in BG than low, over 2 hours they have the same though ○ People who eat lower GI meal don’t report being as hungry as those who ate medium or high GI meal What is the metabolic syndrome? ● Not itself a disease ● Set of risk factors for heart disease, stroke, Type 2 diabetes ● 3 or more of: ○ Blood pressure >/ 130/85 mmHg ○ Fasting blood sugar (glucose) >/ 100 mg/dL ○ Waist circumference >/ 35” womenor 40” men

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○ HDL cholesterol < 40 mg/dL (men) or 50 mg/dL (women) Visceral, intramuscular fat increase insulin resistance ○ Visceral fat makes cytokines ○ Cytokines reduce insulin sensitivity ○ Also increase inflammation ○ Normally this would free up energy to fight infection Associated w/ higher risk of heart attack, stroke, T2D ○ Directly affecting people’s health and lives Type 2 Diabetes: ○ Prolonged insulin resistance exhausts beta cells ○ Someone develops lower insulin sensitivity → glucose in blood stream inc → insulin levels go up → beta cells that make insulin start to die → glucose just continues to increase ○ Note: type 1 diabetes is different ■ Per...