Chapter 8: Nutrition and Global Health
Nutritional Status of the World: Low Birthweight
1) 11% of babies in low- and middle-income countries are born low birthweight according to recent estimates 2) about 3% of DALYs lost in low- and middle-income countries are attributable to low birthweight
Nutritional State of the World: Undernutrition
1) 26% of under-5 children are underweight according to most recent estimates 2) rates of underweight vary considerably by region 3) only about 0.5% of total deaths in low- and middle-income countries are directly due to undernutrition 4) deaths are usually "nutrition related"
Nutritional State of the World: Iron
1) About 1.6 billion people were affected by anemia between 1993 and 2005 2) substantial public health problem for children under 5 and pregnant women, especially in low- and middle-income countries 3) 0.7% of DALYs lost in low- and middle-income countries is related to iron deficiency anemia
Nutritional State of the World: Vitamin A
1) About 25o million children suffer from vitamin A deficiency worldwide 2) 6.5% of all deaths of children under-5 in low- and middle-income countries are due to vitamin A deficiency
Nutritional State of the World: Iodine
1) About 70 million people worldwide are affected by iodine deficiency 2) associated with substantial DALYs lost in low- and middle-income countries
Adolescents nutritional needs:
1) adolescents need protein and energy to grow as well as iron, iodine, folic acid, and calcium 2) adolescent girls who are poorly nourished are much more likely to give birth to an underweight child and experience complications during pregnancy than well-nourished girls
Adulthood/Old Age nutritional needs:
1) adults need a well-balanced diet with protein, energy, and iron 2) foods that contain too much fat, cholesterol, sugar, or salt can be harmful 3) older adults need calcium to reduce risk of osteoporosis
How is the nutritional status of infants and children determined?
1) by measuring and weighing them, then plotting weight and height on a growth chart 2) child's position on growth curve indicates if they are developing normally 3) large share of nutritional deficits are mild, but still have negative consequences on development
Infancy and young childhood nutritional needs:
1) children need sufficient protein and energy as well as iodine, iron, vitamin A, and zinc 2) nutritional gaps during this time can cause problems with stature and mental development, and frequent infection 3) grow best and stay healthiest if exclusively breastfed for first 6 months 4) "window of opportunity" is in utero to two years of age
Iodine importance:
1) deficiency associated with a growth on the thyroid called a goiter and the failure to develop full intellectual potential 2) occurs in people who live in mountainous regions where less seafood is consumed and the soil is deficient in iodine
Vitamin A importance:
1) deficiency associated with night blindness and eventually, permanent blindness 2) important to growth and the proper functioning of the immune system 3) impact on the severity of illness and chance of survival from several causes, including diarrhea, malaria, and pneumonia
Iron importance:
1) deficiency causes iron deficiency anemia which is associated with fatigue and weakness 2) iron-deficient pregnant women have an increased risk of giving birth to a premature or low birthweight baby or hemorrhaging and dying in child birth
Zinc importance:
1) deficiency is associated with growth retardation, impaired immune function, skin disorders, hypogonadism, and cognitive dysfunction 2) deficiency is a major risk factor for morbidity and mortality from diarrhea, pneumonia, and malaria
What are the immediate causes of malnutrition?
1) inadequate dietary intake: weakens the body and opens it up to infection 2) illness: makes it harder for people to eat, absorb the nutrients they take in, and raises the need for some nutrients 3) relationship creates a cycle of illness and infection
Nutrition, Health, and Economic Development
1) nutrition impacts health and human development 2) link to what people learn and their productivity Poor nutrition: -impacts maternal health, which affects household income and health of children -affects children's ability to learn in school, which impacts their future prospects -leads to lower productivity in adult workers
Why is nutrition important?
1) nutritional status is intimately linked with health status 2) nutrition is the leading risk factor for loss of health in low- and middle-income countries 3) low-cost, highly effective interventions are available to improve nutrition status
What is undernutrition?
1) outcome of insufficient food intake and repeated infectious disease 2) includes underweight, stunted, wasted, and micronutrient malnutrition 3) raises risk of illness and decreased intellectual capacity in children 4) raises risk of pregnancy-related death and delivering prematurely in women
Pregnancy and birthweight nutritional needs:
1) pregnant women need a sufficient amount of protein and energy as well as iron, iodine, folate, zinc, and calcium 2) fetuses that do not get sufficient nutrition from the mother may suffer from stillbirth, mental impairment or birth defects
Nutritional State of the World: Zinc
1) second most important micronutrient responsible for death and DALYs in children under 5 2) About 4% of DALYs lost in children under 5 years of age are due to zinc deficiency
z-score
a statistical term, meaning the deviation of an individual's value from the median value of a reference population, divided by the standard deviation of the reference population
low birthweight
birthweight less than 2500 grams
body mass index (BMI)
body weight in kilograms divided by height in meters squared (kg/m2)
overweight
excess weight relative to height; commonly measured by BMI among adults; the international reference for adults is: -25-29.99 for grade I (overweight) -30-39.99 for grade II (obese) ->40 for grade III For children, overweight is measured as weight-for-height two z-scores above the international reference
obesity
excessive body fat content; commonly measured by BMI. The international reference for classifying an individual as obese is a BMI greater than 30
stunting
failure to reach linear growth potential because of inadequate nutrition or poor health; stunting is measured as height-for-age two z-scores below the international reference
anemia
low level of hemoglobin in the blood, as evidenced by a reduced quality or quantity of red blood cells
underweight
low weight-for-age; that is, 2 z-scores below the international reference for weight-for-age. It implies stunting or wasting and is an indicator of undernutrition
undernutrition
poor nutrition; the 3 most commonly used indexes for child undernutrition are height-for-age, weight-for-age, and weight-for-height; for adults, undernutrition is measured by a BMI less than 18.5
overweight or obese
refers to those who are nourished to the point of being too heavy for their height or age
malnutrition
refers to those who do not get proper nutrition, whether too little, too much, or the wrong kind
underweight
refers to those who have low weight for their height or age
undernourished
refers to those who lack sufficient energy or nutrients
iodine deficiency disorders (IDDs)
the spectrum of IDDs includes goiter, hypothyroidism, impaired mental functions, stillbirths, abortions, congenital anomalies, and neurological cretinism
Vitamin A deficiency
tissue concentrations of vitamin A low enough to have adverse health consequences such as increased morbidity and mortality, poor reproductive health, and slowed growth and development, even if there is no clinical deficiency
malnutrition
various forms of poor nutrition. Underweight or stunting and overweight, as well as micronutrient deficiencies, are forms of malnutrition
wasting
weight, measured in kilograms, divided by height in meters squared, that is two z-scores below the international reference