Transcript chapter four the human body: from food to fuel

Nutrition in Childhood
through Adulthood
We discussed basic concepts of nutrition:
-
Food choices and nutritional guidelines
Digestion
Carbohydrates, lipids, and proteins
Energy balance and body composition
Vitamins
Water and mineral balance
We then discussed applications of those concepts to
sports nutrition and to maternal and infant nutrition.
Today we will move on to discuss nutrition from childhood
through adulthood.
Infants
World Health Organization recommendations:
- 75% of infants breastfed initially
- 50% of infants breast feeding at 6 months
- breastfeeding for at least the first 2 years.
- breast milk or formula should be supplemented
with solid food beginning at 4 to 6 months.
Infants
Since this breastmilk will be the infant’s only source of
nutrition for many months, and a subtantial part of her
nutrition for up to two years, it must contain all of the
essential nutrients:
- carbohydrates
- lipids, including essential fatty acids
- proteins, including essential amino acids
- vitamins
- minerals
- water
Infants
Since this breastmilk will be the infant’s only source of
nutrition for many months, and a subtantial part of her
nutrition for up to two years, it must contain all of the
essential nutrients:
- carbohydrates
- lipids, including essential fatty acids
- proteins, including essential amino acids
- vitamins
- minerals
- water
It also contains antibodies and immune cells to help the
infant resist infections, and compounds which are natural
laxatives.
Infants
In some cases the mother either can not breastfeed her
infant or chooses not to.
There are a number of infant formulas
available which are designed to provide
adequate nutrition.
Most of these use cows’
milk as the base, although some use soy
compounds or other liquids. While adequate
for most infants, they can not completly
mimic the contents of breastmilk.
Infants
Most infants are ready to being eating solid foods by the age
of about 4 to 6 months.
- They can sit with the head upright,
minimizing risk of choking
- They lose the extrusion reflex of the
tongue and can use it to move food
from the front to the back of the
mouth where it can be swallowed
- Their intestines and pancreas are producing enough of
the necessary digestive enzymes
- They can drink enough liquids to maintain hydration
Infants
By six to eight
months most
infants can grasp
“finger foods”.
Within a year,
most infants can
begin self-feeding
with a spoon. At
this point most
foods are appropriate.
Infants
By one year of age, most children need
about 850 to 1,000 kilocalories per day,
nearly half of what they will require as
adults. Their need for carbohydrates and
proteins are, pound for pound, much higher
than they will ever be again as they get
older.
One year old: 22 pounds
Adult: 150 pounds
Total calories
850-1,000 per day
1,800-2,200 per day
Carbohydrate
100 grams/day
130 grams/day
Protein
10-13 grams / day
50-55 grams /day
Children
At about one year of age, the infant’s
rapid growth slows down and will
remain moderate until the next rapid
growth period begins during puberty
and adolescence.
Their nutritional needs also slow down
One year old
22 pounds
Three year old
32 pounds
Eight year old
55 pounds
Total calories
850-1,000 per day
1,000-1,200 per day
1,200-1,400 per day
Carbohydrate
100 grams/day
130 grams/day
130 grams / day
Protein
10-13 grams / day
13-15 grams /day
20-30 grams / day
Children
As long as the child eats a variety of
healthy foods she or he should get the
necessary nutrients.
Of particular concern are vitamin D,
vitamin E, iron, and zinc, although all of
the micronutrients should be monitored.
Supplements can be used for children with
special needs such as those who are ill or
who have food allergies causing them to avoid certain foods,
but these should be used cautiously to avoid overdoses.
Children
“As long as the child eats a variety of
healthy foods”, of course, is much easier
said than done.
Most children develop food preferences
and avoidances, often influenced by
advertising, typically preferring sweet or salty foods and
avoiding many fruits and vegetables (just watch the
commercials on TV shows designed for kids!) Prepared
foods like fast-food burgers/hot dogs/fries/tacos/chicken etc,
pizza, or desserts are high in fats, sugars, and/or salt.
Children
“As long as the child eats a variety of
healthy foods”, of course, is much easier
said than done.
Visit any school lunch cafeteria: the
pizza, cookies and chocolate milk are
eaten but most of the vegetables and
fruits are thrown away.
Children
“As long as the child eats a variety of
healthy foods”, of course, is much easier
said than done.
At any children’s parties the staples are
prepared foods like pizza or hamburgers,
cake, ice cream, candy, and carbonated
soft drinks.
Children
“As long as the child eats a variety of
healthy foods”, of course, is much easier
said than done.
According to the National Soft Drink
Association (NSDA) the average person
consumes over 600 12-oz servings (that’s
900 gallons) per year. More than 90% of
elementary school aged children (5-11
years old) average at least 12 oz per day.
Children
Obviously, ensuring good nutrition in childhood is difficult,
with problems occurring at the two extremes:
- Undernutrition / malnutrition
- Overnutrition leading to obesity
Children – Undernutrition & Malnutrition
In the United States, more than 12 million children grow up
in households called “food insecure”:
> 3,000,000 do not have enough to eat
They are deficient in calories and in most nutrients
> 9,000,000 consume enough calories but are
deficient in specific nutrients.
complex carbohydrates
protein
vitamins and/or minerals
Children – Undernutrition & Malnutrition
Worldwide, more than 20,000,000
children under the age of five suffer
from severe undernourishment.
Nearly 6,000,000
children die from
undernourishment
each year – half of
all child deaths.
Children – Undernutrition & Malnutrition
“Malnourished children have lowered
resistance to infection; they are more
likely to die from common childhood
ailments like diarrhea and respiratory
infections. For those who survive,
frequent illness saps their nutritional
status, locking them into a vicious
cycle of recurring sickness, faltering growth and
diminished learning ability.”
United Nations International
Children’s Emergency Fund
(UNICEF)
Children – Undernutrition & Malnutrition
In the United States, a number of public and private
programs attempt to help meet the nutritional needs of
children:
- School breakfast and lunch programs
- Women, Infants, and Children (WIC)
- Supplemental Nutrition Assistance Programs
(food stamps)
- USDA Child and Adult Care Food Programs (CACFP)
- Food banks
Children – Overnutrition & Obesity
At the other extreme is childhood obesity
20% of US children aged 1–11 are obese.
30 years ago this was only 7%.
The percentage of adolescents aged
12–19 who are obese increased from
5% in 1980 to more than 18% now.
Children – Overnutrition & Obesity
Obesity is a problem of both nutrition and physical activity
“Positive Energy Balance” results when
energy intake
exceeds
energy output
At the same time that obese children are taking in too
many calories, usually in the form of fats, many of them
are also deficient in protein, vitamins, or minerals.
Children – Overnutrition & Obesity
Most obese children are eating unbalanced diets
- Highly processed foods
- Fewer fruits, vegetables, legumes,
seeds, nuts, whole grains
- High in sugars
- Low in complex carbohydrates
- High in saturated fats
- Low in polyunsaturated fats
- High sodium
- Deficient in iron, calcium, zinc, other minerals
Children – Overnutrition & Obesity
Obese children are at risk for a number of conditions:
- Diabetes
- High cholesterol
- High blood pressure
- Early heart disease
- Poor bone growth
- Muscle weakness
- Early sexual maturation
Children – Overnutrition & Obesity
Obese children are at risk for a number of conditions:
- Diabetes
- High cholesterol
- High blood pressure
- Early heart disease
- Poor bone growth
- Muscle weakness
- Early sexual maturation
Obese children also often face
increased social and psychological
problems.
Adolescence
As children get older and enter adolescence, they enter a
period of rapid growth and sexual maturation which causes
changes in their nutitional needs.
On average, the most rapid period
of growth occurs between the ages
of 10 and 12 in girls and between
the ages of 11 and 14 in boys, but
there is a lot of variation in when
this occurs in different individuals.
Adolescence
Growth is typically linear at first, with growth of the bones
of the limbs and vertebrae causing increases in height.
Girls typically grow most rapidly just
before menstruation starts
(“menarche”) and reach 90-95% of
adult height by then.
Boys typically continue to grow taller
for about two more years than girls,
reaching 90-95% of adult height
as they become sexually mature.
Adolescence
As linear growth (height, limbs) slows down, growth of
body mass (weight) continuesas bones thicken, muscles
get larger, andconnective tissues are formed.
This growth of bone, muscle, and
other tissues requires significant
amounts of additional protein,
calcium, phosphorus, sodium,
potassium, iron, and many vitamins
as well as additional calories.
Adolescence
.
Eight year old
55 pounds
Twelve year old
90 pounds
Eighteen year old male
150 pounds
Total calories
1,200-1,400 per day 1,850-1,900 per day
2,830 per day
Carbohydrate
130 grams/day
130 grams/day
130 grams / day
Protein
20-30 grams / day
35 grams /day
52 grams / day
Eighteen year old female
125 pounds
Total calories
2,360 per day
Carbohydrate
130 grams / day
Protein
46 grams / day
Adolescence
Diet and exercise are both important for normal growth
- Healthy weight gain ages 12 – 18 years
30 - 40 lbs for girls
50 - 60 lbs for boys
- Changes in body composition
- Boys age 12: 13-23% body fat
age 18: 10-20% body fat
- Girls age 12: 16-29% body fat
age 18: 17-31% body fat
Adolescence - Obesity
As noted before, obesity is a major
problem in adsolescents as well as in
younger children:
The percentage of adolescents aged
12–19 who are obese has increased
from 5% in 1980 to more than 18% now.
At the same time they are taking in too many calories,
usually in the form of fats, many obese adolescents are
also deficient in protein, vitamins, or minerals.
Adolescence - Obesity
Most obese adolescents are eating unbalanced diets
- Highly processed foods
- Fewer fruits, vegetables, legumes,
seeds, nuts, whole grains
- High in sugars
- Low in complex carbohydrates
- High in saturated fats
- Low in polyunsaturated fats
- High sodium
- Deficient in iron, calcium, zinc, other minerals
Adolescence - Obesity
They are at risk for the same conditions as obese children:
- Diabetes
- High cholesterol
- High blood pressure
- Early heart disease
- Poor bone growth
- Muscle weakness
- Early sexual maturation
Adulthood
At about the age of 17 to 18,
growth slows down as the
individual finishes puberty and
adolescense and enters
adulthood.
This is a period of relatively
stable body composition and
nutritional needs, which we
discussed in the first half of
this course.
Adulthood
Many adults are able to maintain healthy eating habits and
physical activity levels and stay
relatively healthy for many years.
Adulthood
Many adults are able to maintain healthy eating habits and
physical activity levels and stay
relatively healthy for many years.
Other adults develop unhealthy
eating habits: high in prepared
foods, low in
fruits and vegetables; high in simple
sugars, low in complex carbohydrates;
high in saturated fats; high in sodium;
deficient in vitamins and minerals.
Many become physically inactive.
Adulthood
This sets the pattern for healthy or unhealthy eating
patterns and exercis habits as these individuals move into
older ages.
Adulthood
Growing Older
Age-related changes:
- Decreased physical activity
- Add fat; lose lean body mass
- Reduced muscle and skeletal strength
- Decline in immunity
- Decline in vision,hearing, taste, smell
- Digestive changes:
loss of teeth
reduced acid secretion
reduced motility
decreased pancreatic & liver function
Growing Older
Growing Older
With aging, calorie needs decline somewhat if the
individuals becomes less active, but remain high if they
remain active.
As always: a healthy diet is best
- Fruits and vegetables
- Complex carbohydrates
- Polyunsaturated fats
- Low sodium
Growing Older
There are some specific dietary needs as we we get older:
Vitamin D needed for bone health, calcium balance
Reduced ability to absorb vitamin B1
Folate, B6, B12 may help reduce heart disease risk
Calcium needed to mnimize
bone loss
Iron needed to maintain healthy
blood cells
Magnesium needed for normal
metabolism & muscle health
Zinc needed to help wound
healing to maintain immunity
Growing Older
Many older individuals have trouble getting enough protein
in their diets:
Growing Older
However, many individuals remain
healthy and active well into their
seventies and eighties, and
occasionally even older:
- Healthy diet
- Exercise