Regions closer to the equator are closer to the Sun
-> receive more UVR than regions further from the equator

sunlight reaches the Earth with diff levels of UVR depending on location

In regions where UVR is diffuse, light skin allows enough UVR to get through skin

in regions where UVR is concentrated, dark skin allows just enough UVR to manufacture vitamin D, thus preventing breakdown of folic acid which is crucial for brain development

our bodies require the right amount of UVR to manufacture Vitamin D

lactase persistence->ability to break down lactose into simple sugar, slowly accumulated in gene pool of special regions

while everyone has the same biological potential to process lactase, this potential does not unfold similarly in everyone, resulting in some being lactose intolerant

domestication of cows eventually led to the practice of consuming dairy products

research on cultural neuroscience reveal genetic diff in social sensitivity

cannot be attributed to genetic accounts cos countries have not experienced influx of people carrying overweight genes

seeing others eat more -> more likely for us to eat more as well

mirror neurons make us copy maladaptive behaviours of others unconsciously

subtle difference in attitudes between "eating to quench a physical need" and "stuffing oneself up"

Mindlessly adding 100 calories per day without burning any more calories will result in adding 1 pound per month

French cuisine have diets very high in fat but they have lower rates of heart disease

french spend longer time than Americans eating their food -> view eating as more leisurely and enjoyable

compared to top administrators, members of executive class, clerical staff and unskilled labourers were more likely to die

mortality is not due to diff access to healthcare since its free for all

with almost every increase in income, mortality rates are lower and these diff emerge even among those whose incomes are at the highest levels

refutes argument that lower SES have more hazardous work situations since all the UK civil servants worked in an office

lower SES more likely to engage in unhealthy habits & behaviours BUT even when these are controlled for there's still a diff between SES and health

less able to make sound decisions that impact future health outcomes

even visiting NYC predicts higher stress and weaker immune system. Leaving NYC predicts a drop in stress levels

Could explain perhaps low SES have poorer health due to less perceived control of their life

residents given control over minor life events eg. watering plant

those with opportunities for control required fewer medicine and lived longer than those in no-intervention group