Transcript A.3 Special Issues in Human Nutrition

A.3 SPECIAL ISSUES IN HUMAN NUTRITION
(ASSESSMENT STATEMENTS)
A.3.1 Distinguish between the composition of human milk and
artificial milk used for bottle-feeding babies.
A.3.2 Discuss the benefits of breastfeeding.
A.3.3 Outline the causes and symptoms of Type II Diabetes.
A.3.4 Explain the dietary advice that should be given to a patient
who has developed Type II Diabetes.
A.3.5 Discuss the ethical issues concerning the eating of animal
products, including honey, eggs, milk and meat.
A.3.6 Evaluate the benefits of reducing dietary cholesterol in lowering
the risk of coronary heart disease.
A.3.7 Discuss the concept of food miles and the reasons for
consumers choosing foods to minimize food miles.
HUMAN BREAST MILK VS. POWDERED
BABY FORMULA
There are fundamental differences between breast milk and powdered
formula.
• Powdered formulas are usually made from cow’s milk. The baby
formula market is big business.
• Breast milk contains substances that formulas do not (the enzymes
amylase/lipase), white blood cells such as macrophages, antibodies
and hormones) - (see next slide).
 Human milk has about 50% more lactose than cow’s milk. Additionally,
human milk has more cholesterol – for building new cell membranes
and nerve cells.
 Some babies are naturally lactose intolerant (although very rare). Baby
formulas that are lactose-free are available. Acquired lactose
intolerance can develop (are before age 5 and unusual before age
10) while secondary lactose intolerance can result from some
common intestinal disorder in babies (this condition is far less frequent
in breastfed babies).
The symptoms of lactose intolerance include vomiting, diarrhea,
abdominal pain, and rashes.
HUMAN BREAST MILK VS. POWDERED
BABY FORMULA
In terms of protein, human milk has lower levels of protein than
cow’s milk. This is primarily because humans do not need to grow
as fast as calves during the first year of life.
 Human milk contains higher levels of the amino acid taurine
than in cow’s milk. Taurine has been linked to brain
development.
 Milk protein comes in two varieties: (1) An easily digestible, liquid
form called whey; and, (2) A more difficult to digest, solid form
called curd (made of a protein called casein).
 Human milk contains 65% whey and 35% casein.
 Cow’s milk contains 18% whey and 82% casein.
Animal milk is heat-treated before being marketed. This process
denatures protein and may cause allergic reactions in infants.
HUMAN BREAST MILK VS. POWDERED MILK (BABY
FORMULA)
Breast-Milk
Colostrum
Present. A thick, sticky and yellowish form of milk
produced in late pregnancy and the first few days
after birth. More info HERE. Colostrum has high
concentrations of carbs, proteins, antibodies,
macrophages, beneficial bacteria, growth
modulators and a mild laxative to clear excess bilirubin
and encourage the baby’s first stool (meconium).
Baby Formula
(usually made from cow’s milk)
Not Present
Antibodies
Present in colostrum in high concentrations but low
volume.
Proteins
Present in lower amounts than baby formula but is
easily digested/absorbed. The enzymes amylase and
lipase. Hormones are present. Taurine (amino acid)
present in high amounts—linked to brain
development.
Higher concentrations but harder to
digest/absorb. Derived from bovine
(cow) sources.
Carbohydrates
Present. High in lactose. Linked to brain development.
Lower in lactose. May come from
glucose.
Lipids, Cholesterol
& Fatty Acids
Present. Human fatty acids. Newborns need
substantial quantities of lipids and lipid content in
breast milk can vary depending on the baby’s needs.
Lipids are required to build phospholipids for new cells
and the help build nerve cells.
Palm, corn, coconut, soy or safflower
oils.
Vitamins and
Minerals
In lower concentrations than baby formula but easier
to absorb. Iron is present but in lower concentrations
than baby formula.
In higher concentrations, but harder to
absorb.
Not Present
HOW TO BREASTFEED
(CAUTION: SOME NUDITY)
SCANDALS
ARGUMENTS FOR BREASTFEEDING OVER
FORMULA
AREA
EFFECT
WHO BENEFITS
Immunity
Colostrum and early breast milk contain
high concentrations of antibodies &
macrophages, protecting the infant from
infections until immunity develops.
The Child
Digestive Function
Colostrum stimulates digestive tract function
of baby and eases defecation. Easier to
digest than formula milk.
The Child
Cost
Breast milk is both free and readily available
so long as both mother and child are
healthy.
The Child
Nutrition
More complete than baby formula.
Composition of breast milk can change
depending on the needs of the baby.
The Child
Mother and Child
Bonding
Aids in mother/child bonding and
communication.
The Mother & Child
The Mother’s Health
Aids in weight-loss, reduces breast cancer
risk,/Type II Diabetes, and post-partum
depression risks.
The Mother
Continued on Next Page
ARGUMENTS FOR BREASTFEEDING
OVER FORMULAS
AREA
EFFECT
WHO BENEFITS
Sleep
Some of the proteins in breast milk help to induce sleep in
infants. Not present in cow or soy milk.
Mother & Child
Contamination
No need to prepare, wash or sterilize glass or plastic
bottles and synthetic nipples, as in the case with infant
formula. In the preparation of bottle milk, there is a risk of
water being polluted /bottle contamination with bacteria.
Child
Allergies
The risk of allergies is not present, whereas cow’s milk in
particular carries multiple risks of inducing allergies.
Child
Specificity
Human milk is species-specific. It is designed to meet a
human baby’s nutritional needs at each developmental
stage w/out upsetting the delicate digestive system. The
high percentage of whey and lower levels of casein make
human milk more digestible than cow’s milk. The overall
lower protein level is better suited to humans.
Child
Menstruation
Breastfeeding causes the uterus of the mother to return to
‘normal’ after delivery. It also inhibits the onset of
menstrual cycles, acting as a natural contraceptive ,
encouraging space between babies.
The Mother
Nutrients
The nutrients in human milk are more easily digestible into
the child’s blood stream (particularly iron and vitamins.
Child
POST-PARTUM DEPRESSION
ARGUMENTS AGAINST BREASTFEEDING
 Breastfeeding can be painful for the mother (sensitive or infected
nipples). The pain can be while the baby feeds or it can be from
engorgement (the breasts are full of milk).
 Women who carry certain pathogens are advised not to
breastfeed because of the risk of passing them to the child. HIV
can be passed from mother to child through breast milk. The
benefits of breast milk would be outweighed by the dangers of the
virus. EARLY TREATMENT IS SAID TO CLEAR H.I.V. in 2nd BABY.
 Some cultures do not accept breastfeeding in public.
 In exclusive breastfeeding, the father of the child may feel “left
out” whereas in bottle feeding, he can share a certain bond with
the child.
 Although some countries have laws which allow the mother to take
breaks to breastfeed during her work day, many countries do not.
TYPE II DIABETES
Type II diabetes is the most common form of diabetes worldwide and
develops as a result of the complex interplay between genetics and
.
(Also known as ‘adult-onset diabetes’ or diabetes mellitus type II or
non-insulin dependent diabetes mellitus (NIDDM)).
• Type II diabetes results from the body developing an insensitivity to
insulin over a period of years. While it is most common in
overweight or obese adults over age of 40, it is now being
observed in overweight children.
• Some groups have a higher incidence of Type II diabetes than
others: (1) Native Australians (Aborigines); (2) Native Americans;
and (3) Maoris.
TYPE II DIABETES
(ANIMATIONS)
Reminder: Beta cells in the pancreas produce insulin while
Alpha cells produce glucagon.
STATISTICS AND SYMPTOMS
(CAN BE MILD AND DEVELOP OVER A PERIOD OF YEARS)
Symptoms: (1) being more thirsty than usual; (2) urinating
more than usual; (3) feeling tired and fatigued all the
time; (4) more infections than usual (skin infections in
particular); (5) elevated blood glucose levels and
glucose in the urine.
DIETARY ADVICE FOR TYPE II DIABETICS
(GAINING CONTROL OF BLOOD GLUCOSE LEVELS)
1. Decreasing body mass and maintaining a healthy
BMI through exercise and a proper, well-balanced
diet.
2. Eating foods rich in fiber and complex carbs,
cutting down on saturated fat. Complex carbs
release their energy slowly. Fiber allows nutrients to
be absorbed slowly over time.
3. Eating small, regular meals throughout the day.
4. Eat lots of fresh fruits and vegetables. Low GI foods.
5. Exercise.
THE BENEFITS OF REDUCING
CHOLESTEROL (LDL)
Cholesterol is an essential component (lipid) of the human body. It is
considered a steroid and often is the basis for various hormones and cell
membranes.
• There are two main types of cholesterol (HDL vs. LDL). High LDL (lowdensity lipoproteins) levels are associated with increased risk coronary
heart disease. Research has shown that a 10% rise in blood cholesterol
plasma levels is associated with a 30% increase in the risk of death from
CHD. It appears as though total blood cholesterol levels are less
important the LDL levels.
• Diets that are high in saturated are linked (positively correlated) with
high LDL and total blood cholesterol levels, along with CHD.
• Cholesterol levels do have a genetic component and high cholesterol
levels tend to run in families.
• High LDL levels promote inflammation and plaques.
Reducing saturated fat consumption and high animal product
consumption is a first step in lowering cholesterol. Diet and exercise are
critical. Medications may be necessary.
CHOLESTEROL
THE IMPORTANCE OF FIBER
Fiber is plant material, made up of the polysaccharide cellulose, that
cannot be digested by the small intestine. Cellulose from plant cells
walls is the main component of dietary fiber (although fungi and
crustaceans have cell walls made up of the polysaccharide chitin.
1. Fiber helps to prevent constipation, by increasing the bulk of
material in the large intestine.
2. Fiber might help to prevent obesity by increasing bulk in the
stomach, reducing the desire to eat.
3. Fiber may reduce the risks of appendicitis, colon cancer, and
hemorrhoids.
4. Fiber might slow the rate of sugar absorption, helping to prevent
and treat diabetes.
FOOD MILES
The term ‘food miles’ was coined to express the distance from where
food was produced to where it is consumed. The longer the distance
food has to travel, the greater the environmental impact.
FOOD MILES
(THE CONTROVERSY)
• Some consumers now refuse to buy foods with high food miles,
preferring to buy food that is ‘local.’ Other consumers are not
concerned about food miles and, instead, want continuity of
supply throughout the year and maximum choice of world foods.
Environmentalists point out that there are other energy costs in food
production, including the use/abuse of cheap labor, pesticides and
fertilizers, increased air pollution, traffic congestion, and release of
greenhouse gases.
ETHICAL ISSUES OF MEAT CONSUMPTION
Many people choose what to eat, based on likes and dislikes,
availability, choice and cost. Some people also have ethical reasons
for not eating certain foods.
Background:
• Vegetarians do not eat the flesh of any animals: no red meat, no
poultry, and no fish.
• Some vegetarians (vegans) do not eat ANY animal products (eggs,
milk, dairy, honey) or any product that contains animal products.
• For some vegetarians and vegans, vegetarianism goes even further
. . . They will not wear/use leather, fur, wool or silk.
ETHICS OF EATING ANIMAL PRODUCTS
Meat: Animals have to be killed to obtain meat, usually after rearing them on a farm or In a factory.
• Is it right for one animal to take the life of another animal to obtain food?
• Is the pain caused to animals during transport/slaughter justified?
• Is the suffering of animals reared for meat in unnatural and crowded conditions justifiable.
• What are the consequences of land deforestation, antibiotic/hormone use?
Milk: Cows and other mammals produce milk after giving birth. This milk can be used for human
consumption if the calf or young mammal is separated from its mother soon after birth.
• Is the huge milk production of cows acceptable, given that it is associated with health problems
and a short life expectancy?
• Is the suffering of cows whose claves are taken away soon after birth justifiable?
• Is it acceptable to make cows have calves in order to stimulate milk production, when these
calves will only be killed?
Eggs: Most eggs come from hens (female birds) that have been specially bread for prolific egg
production.
• Is it acceptable to breed and keep kens that produce far greater numbers of eggs than their wild
relatives?
• Is the suffering of egg-laying hens kept in unnatural conditions justifiable—small cages or large
groups.
• Is it acceptable to kill male chicks at 1-3 days old because they do not lay eggs.
Honey: Bees are kept alive in hives and surplus honey is removed when available.
• Is it justifiable to take honey from bees that have stored it for their own use within the bee colony?
• Is it acceptable to keep bees in an area where the bees will compete with wild insects that forage
on nectar from flowers?
THE STATS & SHOCKING FACTS
ETHICAL ISSUES AND MEAT CONSUMPTION
Arguments for a Vegetarian Lifestyle:
 Killing sentient beings is wrong, especially if it is not necessary for survival. ‘Sentient’
means having a nervous system, implying the organisms can perceive sensations
like pleasure or pain.
 Raising animals for the sole purpose of slaughtering them for human consumption
is wrong.
 Intensive livestock production is a wasteful industry which misuses valuable
resources and land.
 Mass –production/factory industrial farming uses practices that are unnecessarily
cruel including penning up animals, restricting their movements, cutting/burning
off beaks, exposing animals to artificial light only, transporting them in
uncomfortable conditions over long distances.
Arguments Against Vegetarianism:
 Farm animals such as cows, sheep, pigs and chickens would not exist if not raised
for food.
 Without meat production and fishing industries, thousands of jobs would be lost.
 Meat and fish can be grown in decent conditions as in ‘free-range’, ‘free-fromcruelty’, and organic practices.
FACTORY FARMING ANIMATION
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