Nutrition, Health & Child Growth Flashcards
what is the Environment of evolutionary adaptation (EEA)? example?
- the ancestral environment to which a species is adapted.
- Paleolithic foragers
how did agriculture impact health and diet?
• Health and diet decline with transition to agriculture
○ Ie. The first epidemiological transition
○ Paleopathology
what is the oseteology paradox? how are contemporary dietary patterns flawed?
- concept that those who exhibit pathological lesions on the skeleton are a biased sample - had to live long enough for the disease to progress to the bone
• Contemporary dietary patterns at odds with those typified most of our evolution as a species
how do diets in wealthy countries differ from hunter-gatherer diets?
• Diets in wealthy countries deviate substantially from hunter-gather diets
○ e.g. less micronutrients, over consumption of carbohydrate rich (ultra) processes cereals
○ Higher risk of chronic illnesses
why are certain chronic illnesses not selected against?
• Chronic diseases such as cardiovascular disease (CVD), diabetes and cancer typically cause morbidity and mortality later in life
○ Therefore not selected against
how has nutrition changed globally?
• The nutrition transition (popkin):dietary, physical activity, and body composition changes occurring at great speed+ at earlier stages of economic and social development.
- the obesity and diabetes epidemics
how big of an issue is obesity? what is the double burden of malnutrition?
• Obesity as an issue of global proportions
○ Coexists with undernutrition (the double burden of malnutrition)
are all obese people at risk of disease? is BMI a sure indicator of health?
• Not all obese bodies are at risk (ie fat patterning)
○ Some people with obesity are metabolically healthy
○ Both high and low bmi associated with risk - not a sure indicator
what other factors contribute to risk of obesity?
Mortality risk changes by age and differs by gender
why does BMI differ globally?
○ Pop. Differences in meaning of bmi
§ Thin-fat phenotype
• Thiness and fatness as social and biological categories - they are subjectiveChanging views of fatness as wealth, thinness as health
how is the global epidemic of diabetes distributed? what group is at highest risk?
• The global epidemic of diabetes is not evenly or uniformly distributed
○ In developing countries - the newly prosperous groups
○ in the developed world - the socio-economically disadvantaged
○ Indigenous peoples are at highest risk globally
who postulated the thrifty gene hypothesis?
• Neel (1962) postulated the existence of metabolically thrifty genes
describe a “thrifty gene”
○ More efficient food utilization, fat deposition and rapid weight gain at occasional times of food abundance (feast)
Making the gene bearer better able to survive famine
what do thrifty genes cause in the modern world? why? what is the coca-colonization?
• In our modern world, “thrifty” genes lead to obesity and diabetes due to a change in lifestyle
○ Spread of this lifestyle to the developing world = coca-colonization
how does the thrifty gene foster a racialized view?
○ Race becomes a biological entity and independent risk factor
- No account of socioeconomic status, history, or culture
what is the thrifty phenotype hypothesis?
• Exposure to nutrient scarcity during the fetal and infant phases of development results in metabolic programming for thriftiness
○ Developmental rather than evolutionary adaptations
describe the DOHaD
he developmental origins of health and disease (DOHaD)
○ Maternal undernutrition and the dutch famine
○ Expanded to explore a variety of adverse life experiences
• Epigenetic changes
○ e.g. Y chromosome and civil war POWS - the draft, intergenerational trauma transferred paternally
how is life history shaped?
• Constraints of time and energy shape life history evoution in all organisms
○ Growth and maturation
○ Reproduction
two ways socio-cultural phenomena influence human life history process?
- Economic conditions
2. Socio-cultural norms (e.g. childhood feeding, birthspacing, gender biases)
what is the most critical window for growth and health?
• Conception to 2 yrs is the most critical window for growth and health
how is breast milk tailored to infant growth?
○ Key nutrients, hormones, antibodies (igA) to help protect from infections
○ Not high in energy: designed to be consumed frequently
what are our traditional infant growth standards based on?
• Traditional growth standards based on formula fed infants
○ Grow differently from breast fed
what is WHO’s biological norm for growth? shown by?
• WHO: breast-fed infant as biological norm for growth
○ Growth curves and virtually identical from various participating countries (in optimal health conditions)
what are the main contributors to poor growth? what kind of relationship is it?
Under-nutrition and infections are main contributors to poor growth (growth deficits)
• Synergistic relationship
what are wasting or stunting? what is the biological standard of living
wasting - low height for child’s weight
stunting - low weight for child’s height
○ Height as the biological standard of living
describe Bogin and colleagues findings with mayan children in guatemala and in the US
stunting in guatamalan children
Growth is extremely sensitive to social conditions
what are secular trends? example?
• Secular trends: changes in growth and development across generations
○ e.g. increased average height over 20th century
- Noticeable differences between rich and poor
how do economists view stunting?
• stunting as “adaptive” in resource scarce environments - ignores
underlying cause of growth deficits and the negative health consequences
3 criticisms of economist view of stunting?
- Adaptations are not “good” but a trade-off between size and survival (developmental adaptation)
- Assumes stunting is solely the effect of food shortage - ignores the synergistic relationship with infectious disease (especially diarrheal) and psychosocial stress
- Why people live under such conditions not addressed
how does rapid growth impact puberty?
• Rapid growth accelerates reproductive development leading to earlier puberty and age at menarche
is the age of menarche standardized worldwide? associated trend?
○ Age at menarche varies around the world
○ Secular trend in downward age at menarche
describe menarche in the bundi of new guinea - was it high or low? how did it change with changed conditions?
○ Had the highest reported age at menarche (18 years)
○ Rapidly declined with increased access to energy-rich foods and health care
what disconnect exists between social maturity and reproduction maturity? result?
• Declines in the age of biological reproduction maturity do not match declines in the age of social maturity
○ Disconnect results in novel health issues (e.g. teen pregnancy)
