Health

Overview of the dayFoodExerciseSleep and restInfectious Diseases“Old wives tales”

Health and evolution

For 99% of the time humans have been on earth, they were hunter-gathers 1.2 million years ago to about 10,000

years ago: Hunter-gatherers: 10,000 years ago: Agriculture 200 years ago: Industrial revolution 80 years ago: Modern medicine

Our bodies are adapted to living as hunter-gatherers

Mismatch hypothesis

The stone age way of life to which our biological and psychological make-up is still adapted is very different from the modern, western environment. Therefore, we are mismatched--psychologically and biologically--to the modern environment.

Food

HG diet: 22% fat, 41% carbohydrates, 37 protein

We are adapted to crave: fats, sweets, salt Scarce and hard to get in the EEA

Modern diet: 42% fat, 46% carbohydrates, 12% protein Abundant and easy to get

The modern diet

Too much fat, sugar, and saltCravings remain the sameEasy to get Concentrated forms Dense calories

Diet Niches: The case of spice usage

Why do spices taste good? They are good for us, they have antimicrobial

properties--they kill harmful bacteriaWhere are spices most widely used?

Hot climates (where bacteria in foods are more likely to occur)

In what type of foods are spices most widely used? Meat dishes (more likely to spoil than vegetable dishes)

Exercise

Hunter-gatherers: Were fit They engaged in frequent aerobic exercise Had low % of body fat Had frequent rest days

Most modern humans Are out of shape (only 10-15% get regular

exercise)

Sleep

Sleep deprivation has reached epidemic proportions in the US and other modern societies

Evolved sleep needs: 8-9 hours per night 20 minutes of a mid-afternoon nap

Current sleep patterns: about 6-7 hours (or less) per night, and no naps

Why we don’t get enough sleep

Technologies not available in EEA Electric lights TV, movies, Web Industrialized methods of production

New cultural patterns and values shift-work mass education negative attitudes toward sleeping

Problems associated with a lack of sleep

Mental: Impaired mental functioning decreased problem-solving capacity less alert (because cortisol is produced during sleep)

Biological obesity and diabetes

lack of sleep inhibits the production of human growth hormone (which controls fat and muscle production), leptin (a hormone that makes you feel full when you are), and insulin (which regulates glucose absorption)

Lack of sleep...

Increases risk of infection lack of sleep lowers white blood cell count

Decreases testosterone levels in menAffects estrogen levels in women

too little sleep (in darkness) inhibits secretion of melatonin

melatonin regulates estrogen (too little melatonin means too much estrogen)

Evolutionary approaches to proper sleep in the modern world

Throw away your TV (or at least turn it, and your computer, off by 9:30 p.m.)

If you drink alcoholic beverages, do so only in moderation; do not drink before bedtime

Go to bed earlyTake a 20 minute nap in the afternoon Adjust work and education schedules

according to biological sleep realities (e.g., Minnesota high schools)

Nutrition, Exercise, Sleep

Protein plus exercise plus rest builds muscle

Carbohydrates give you energy to exercise

Exercise helps to prevent weight gain grows muscles (which burn more calories than fat)

makes you tired (and want to sleep)

Adaptive Reactions to Infectious Diseases

Coughs, sneezes, and runny nose expel, and spread, bacteria, viruses

Fever kills bacteria

Our aversion to meat and eggs when we are ill (blood-letting reduces iron) bacteria thrive on iron

Vomiting and diarrhea (expel, and spread, toxins)

Old Wives’ tales

How might evolutionary theory explain old wives tales? Guess what chicken soup contains? Sugar and honey can effectively treat

deep puncture wounds Dog saliva and surface wounds Eating clay

Summary

Mismatch hypothesisFoodExerciseSleep and restInfectious Diseases“Old wives tales