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11/17/2015

Does our nutritional needs change as we get
older? How?

LEARNING OBJECTIVES
•Identify the different stages of the human life
cycle
•Explain how nutritional requirements vary
through the stages of human life cycle

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Introduction
• Human bodies change significantly over time, and food is the
fuel for those changes
...

• However, the amounts of nutrients needed differ

The major stages of the human life cycle are defined as follows:
•Pregnancy
...
:earliest part of childhood- from birth through age one
•Toddler years
...
Takes place from ages 4 – 8 yrs
•Puberty
...
takes place between ages 14- 18 yrs
•Adulthood
...
period of adulthood that stretches from age 31-50 yrs
•Senior years, or old age
...
Eddy Owaga
IFBT, DeKUT
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Overview
1
...
Physiology of pregnancy
3
...
Foods/substances to avoid during pregnancy
5
...
Malnutrition and pregnancy
7
...

 Problems with nutrients can occur very early in pregnancy
before woman recognizes she is pregnant
 Folate, Iron, and B12 are especially important for fetal
development; increased needs during pregnancy
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Nutrition before Pregnancy contd…
• Vitamin A supplementation should be avoided as this may
adversely affect the pregnancy
• Conditions such as diabetes, HIV/AIDS, and STDs can adversely
affect a pregnancy and should be managed prior to pregnancy
to ensure a healthy outcome
• Harmful substances, such as cigarettes, alcohol, drugs or
environmental contaminants, can cause miscarriage, birth
defects, and can impair fertility -> eliminate use prior to
pregnancy

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Nutrition & Male Fertility
Although the woman’s nutrition has the most direct influence
on the developing fetus, the man’s nutrition status is also
important, since malnutrition can affect male fertility

• Weight
• Zinc
• Antioxidants
• Alcohol

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Nutrition & Male Fertility
• Overweight and obese men have low sperm counts and
hormonal changes that reduce fertility
• Zinc is a cofactor for enzymes involved in testosterone
production, DNA replication, protein synthesis, and cell division
...
A
deficiency of zinc can impair male fertility but this can be
reversed over time with supplementation
• Antioxidants can help protect sperm from oxidative damage
(free radicals)
...


Overview
1
...
Physiology of pregnancy
3
...
Foods/Substances to avoid during pregnancy
5
...
Malnutrition and pregnancy
7
...
About 30 hours
after fertilization, the zygote reproduces itself by dividing in half
...


•

Blastocyst arrives in uterus about 4-5th day after conception
...


•

When the blastocyst has implanted, at around two weeks after
conception the developing infant becomes an embryo
...
Placenta performs the
respiratory, absorptive, and excretory functions that
the fetus’ lungs, digestive system, and kidneys will
provide after birth
...

• Amniotic sac: a fluid-filled balloonlike structure that
houses the developing fetus; provides protection to
developing fetus
• Umbilical cord: a ropelike structure containing fetal
blood vessels that extends through the fetus’s belly
button-to-be to the placenta
These three structures are expelled from the uterus
during childbirth
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Placental Development
•

there is no actual mingling of fetal and maternal blood (placental villi
are fingerlike projections)
...
25in) has a complete central nervous system, a
beating heart, a digestive system, well-defined fingers and
toes and the beginnings of facial features
•

During the fetal stage is when the major growth occurs: this
infant grew 20 times longer and 50 times heavier during the
fetal stage
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Day 23
• 2mm long (=)
• Beginning
development of
major organs
• Critical stage for
neural tube
development

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Day 28
• 6mm long (===)
• At this point, the
heart is beating,
• Lim buds will form
the arms and legs

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Week 9
• 44mm long
• Embryo has become a
fetus
• Complete CNS-central
nervous system,
beating heart,
digestive system, welldefined fingers and
toes, beginnings of
facial features
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Week 12
• 82mm long, weighs
about 1oz
• Arms, hands,
fingers, legs, feet
and toes formed
• Organs grow and
mature
• Less affected by
nutritional
deficiencies
Still affected by nutritional deficiencies and other insults, but not as
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severe and a full recovery is possible (if not entirely likely)
...
Lungs are
not well developed
...
Preterm infants
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also have less ability to suck and swallow, so feeding is challenging
...
5 lb
• Otherwise
– Low birth weight (LBW)

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Low Body Weight vs very Low Body Weight
• LBW infants < 5
...
5lbs) struggle both in immediate survival and
long-term development
• Preterm infants may be small, but if their size and weight are
appropriate for their age, they can catch up in growth given
adequate nutritional support;

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Critical Periods
• Times of intense development and rapid cell division
– Cellular activities can occur only during these
times
• Organ and tissue development most vulnerable to
adverse influences
• First trimester

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Critical Periods contd…
• Nutritional deficiencies, some medications, high
intakes of vitamin A, or radiation can change or stop
development
...

• Most spontaneous abortions, or miscarriages,
happen during this time
...
If the adversity occurs during the
purple timeframe, the damage is likely to be severe and unlikely to be
reversible
...

• Notice that central nervous system development begins after only two
weeks of gestation; many women may not realize that they are
pregnant at this time
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Neural Tube Development
• Critical period is 17-30 days gestation
• Vulnerable to
– Nutrient deficiencies
– Nutrient excesses
– Toxins
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Neural Tube Defects
• Anencephaly

– Brain either missing
or fails to develop

• Spina bifida

– Incomplete closure of
spinal cord and its
bony encasement

Anencephaly often results in miscarriage; infants born with
anencephaly die shortly after birth
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Neural Tube Development

If the upper end of the neural tube fails to close, the brain will not
develop, resulting in anencephaly
...


Spina Bifida
Spina bifida is characterized by incomplete closure of the spinal cord
and its bony encasement
...
Spina bifida is accompanied by varying degrees of
paralysis depending on damage to spinal cord
...

Grain products are therefore fortified to ensure adequate
intake in women of childbearing age
...
2 to 15
...
That fat serves a
necessary purpose, too: to provide energy for labor and
lactation
...
Most women do not return to their pre-pregnancy
weight
...
Nutrition before pregnancy
2
...
Nutritional needs during pregnancy
4
...
Common concerns during pregnancy
6
...
Risks during pregnancy
54

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Nutritional needs during pregnancy
i) Energy requirements
ii) Protein and fat requirements
iii) Iron requirements
iv) Calcium
v) Folate
vi) Zinc

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Nutrition during Pregnancy
“Nutrition requirements increases tremendously
during pregnancy and lactation as the expectant or
nursing mother not only has to nourish herself but
also growing fetus and the infant who is being
breast fed”
...

• Additional 300 kcal of energy is required during 2nd & 3rd
trimester of pregnancy
...

• It is required for fetal visual development
• It reduces the incidence of heart diseases & heart disease
related deaths in infants
...

•Calcium intake decreases risk of hypertension, pre-eclampsia in
mothers and low birth weights and chronic hypertension in
newborns
...

Recommended daily
pregnancy is 1g
...
5

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Folic acid, Zinc requirement during pregnancy
Folic acid (RDA- 400 µg/d):
•During pregnancy maternal blood formation increases thus folic acid
requirement also increases
...

•

helps prevent birth abnormalities like spina-bifida

•

take a daily supplement of at least 400 micrograms one month before
becoming pregnant and during the first three months of pregnancy

•

green leafy vegetables such as broccoli, spinach and salad greens,
chick peas, nuts, orange juice, some fruits and dried beans and peas

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Zinc (RDA-12mg/d) :
•It is required for synthesis of nucleic acids DNA & RNA and it is having
important role in reproduction
...

•--found in lean meat, wholegrain cereals, milk, seafood, legumes and
nuts

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Fiber requirement during pregnancy

Fiber required:
• high fiber intake combined with plenty of fluid is
encouraged to help prevent constipation
• wholegrain breads and cereal products, legumes,
nuts, vegetables and fruit

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Supplements
• Pregnant women who make wise food choices can meet
most of their nutrient needs, with the possible exception
of iron
• Supplements are routinely prescribed by for pregnant
women by most physicians
...
Nutrition before pregnancy
2
...
Nutritional needs during pregnancy
4
...
Common concerns during pregnancy
6
...
Risks during pregnancy
68

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Foods/substances to avoid during pregnancy
i) Caffeine
ii) Smoking
iii) Alcohol
iv) Drugs

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Foods and substances to be avoided during pregnancy
• Caffeine: Coffee should be avoided during pregnancy as
it can cross the placenta & enter fetal circulation and
increases the risk of miscarriages, premature deliveries
and small for date infants
...

• Smoking impairs oxygen & nutrient transport through
the placenta due to reduced blood flow
...

• Alcohol: During pregnancy alcohol consumption causes low
birth weight infants & growth retardation, fetal impaired
central & nervous system performance including growth
retardation
...


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Overview
1
...
Physiology of pregnancy
3
...
Foods/substances to avoid during pregnancy
5
...
Malnutrition and pregnancy
7
...
Begins
about 3 weeks, ends usually around 3 months
...

• Probably evolved to serve a useful function: to protect
pregnant women and embryo from food-borne infections
and toxins
...
Slowed movement
of GI tract, possibly aggravated by high doses of iron
...

• Generous amounts of fiber, adequate fluids and regular
exercise
...


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HEARTBURN
• Relaxed GI muscles: cardiac sphincter
...

• Avoid lying down right after eating; eat smaller, more frequent
meals; eat less fat, so the stomach will empty faster; avoid spicy
foods
...


76

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FOOD CRAVINGS & AVERSIONS
• Most commonly craved items: fruit and juices; sweets; desserts and
chocolates
• Myth that mothers instinctively know what to eat and cravings are
the result of a natural desire to consume needed nutrients
...
e
...

• Cravings more likely to be related to hormonal changes or to family
traditions
...
Can be risky, craved substances can be toxic and harmful
...

• Most common aversions are to non-alcoholic caffeinated beverages,
meat, fish, poultry, and eggs

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Overview
1
...
Physiology of pregnancy
3
...
Foods/substances to avoid during pregnancy
5
...
Malnutrition and pregnancy
7
...


– Risk of Low Birth Weight, physical and
cognitive abnormalities
80

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Malnutrition and Pregnancy
• Fetal development

– Fetal growth retardation
– Birth defects
– Miscarriage and stillbirth
– Premature birth
– LBW

Without adequate nutrition during pregnancy, fetal
growth and infant health are compromised
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Overview
1
...
Physiology of pregnancy
3
...
Foods/substances to avoid during pregnancy
5
...
Malnutrition and pregnancy
7
...
This can lead to gestational diabetes, which is a high
blood glucose concentration that develops during pregnancy
and returns to normal after birth
...

• The fetus grows to be quite large – increased risk of c-section
...
Also important to limit high GI foods
...

• Preeclampsia

is

the

most

serious

maternal

complication of pregnancy
...

90

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Risks during Pregnancy
Smoking
• Restricts blood supply to fetus: Limits oxygen and
nutrient delivery and waste removal

• Lung development
• Increased risk for:

– Complications
– Low Birth Weight infant
– Lung problems

• Preventable!

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Risks during Pregnancy
Mercury and other
heavy metals
• Some fish contain
high amounts of
mercury
• Mercury can impair
fetal growth and
Central Nervous
System
development
92

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MATERNAL FACTORS THAT INCREASE RISK OF NUTRIENT
DEFICIENCIES AND POOR PREGNANCY OUTCOME

Factor

Condition increasing risk of nutrient deficiencies

1
...
5 or >25
During pregnancy Inadequate or excessive weight gain

Inappropriate pattern of weight gain

2
...
Eating patterns

Regular omission of foods from 1 or more major
food groups e
...
vegan diets
Excessive consumption of a single type of food
Fasting and weight loss diets
Eating disorders
Food cravings, aversions (odors/flavors-), pica (non
food substances clay, rubber, baking soda)

MATERNAL FACTORS THAT INCREASE RISK OF NUTRIENT
DEFICIENCIES AND POOR PREGNANCY OUTCOME

Factor

Condition increasing risk of nutrient
deficiencies

4
...
Sociocultural
factors

Low income
Limited educational achievement
Lack of family and social support

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MATERNAL FACTORS THAT INCREASE RISK OF NUTRIENT
DEFICIENCIES AND POOR PREGNANCY OUTCOME

Factor
6
...
Lifestyle choices

Condition increasing risk of nutrient deficiencies
Food contaminants (Hg, Pb, PCBs, pesticides)
Foodborne illness pathogens
High caffeine intake
Use of alcohol, drugs, tobacco or herbal products

In summary…
...
Nutrition before pregnancy
2
...
Nutritional needs during pregnancy
4
...
Common concerns during pregnancy
6
...
Risks during pregnancy

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11/17/2015

Questions?

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