Milk is the nutrient fluid produced by the mammary glands of
female mammals. The ability to produce milk is one of the
characteristics of mammals, as opposed to fish or birds. Milk
provides the primary source of nutrition for newborns, before
they are able to digest other foods.
Animal milk was first used for adult humans as long ago as
the time of Avrohom Ovinu. When women began to feed it to
their newborns instead of engaging a wetnurse, (a woman who
had given birth and was able to nurse both her own and
another baby) cow's milk, or buffalo milk, frequently caused
problems and even death, in the infant. Those were the days
before pasteurization.
People who prefer raw, untreated milk, argue that
pasteurization kills beneficial micro-organisms and important
nutritional constituents. However, unpasteurized milk can
contain harmful, disease-causing bacteria, such as
salmonella, diphtheria, tuberculosis, E. coli, and polio. In
many countries, it is illegal to sell unpasteurized milk.
Jews who go to small farms in England while they are on
vacation, find it increasingly difficult to buy fresh milk,
as they used to.
In order to prevent spoilage, milk can be kept refrigerated
in tankers in temperatures between 1 and 4 degrees Celsius.
Most milk is pasteurized by heating briefly; it is then
packed into bags, cartons or (more rarely nowadays) bottles,
before being sent to local markets. The spoilage of milk can
be prevented by using ultra-high temperature treatment, which
gives us 'long life' milk. This milk can be stored without
refrigeration for months, until opened.
Sterilized milk is heated for a much longer time, and can be
kept even longer than 'long life' milk, but loses more
nutrients, and does not taste the same. Condensed milk is
made by removing most of the water, and can be stored for
many months without a refrigerator. Milk powder has
practically all the water removed from it, and is the most
durable of all milk, for storage.
When left standing for a few hours, fresh milk has a tendency
to separate into a high fat cream layer on top of a much
larger, low fat milk layer underneath. Fat is lighter than
water. Incidentally, when I was a child, and we bought
several gallons of milk at a time, we used to separate the
top layer of cream and make our own butter, as kosher butter
was not available in England at that time. Today the
separation of cream from the milk is usually done rapidly, in
centrifugal cream separators. The fat globules in goat's milk
or sheep's milk are smaller than those in cow's milk, and do
not form clusters easily: thus cream is much slower to
separate from these milks.
Homogenizing milk is the process which prevents the cream
layer from separating out of the milk. The milk is pumped at
high pressures, through very narrow tubes, breaking up the
fat globules through cavitation and turbulence. As the
enzymes in the milk could break down the fats and cause a
rancid taste, the milk is pasteurized at the same time.
The composition of milk differs widely. For example,
Human milk contains on average 1.1% protein, 4.2% fat, 7.0 %
lactose, and supplies 72 calories of energy per 100 grams.
Cow's milk contains, on average, 3.4% protein, 3.6% fat, 4.6%
lactose, and supplies 66 calories of energy per 100 grams.
Full cream, or whole milk, contains the full fat content,
about 3-4%. (Channel Island milk in England contains 5.5%
fat). For skimmed or semi-skimmed milk, all the fat is
removed, and then, in the case of semi-skimmed milk, some is
returned. Semi-skimmed is the most popular milk, as the full
cream is thought by many people to be unhealthy, and they
claim that skimmed milk has no taste. Babies and small
children need whole milk.
Vitamins D and K are essential for healthy bones.
Iodine is a mineral essential for thyroid function.
Riboflavin is needed for cardiovascular health, as are
Potassium and Magnesium.
Vitamin B is important for energy production.
Thiamine is a B vitamin, important for memory.
Vitamin A is essential for immune function.
Conjugated linoleic acid is only available in milk from grass
fed cows. It is a beneficial fatty acid, that inhibits
several types of cancer in mice. In studies, it has been
shown to kill human skin cancer, colorectal cancer, and may
help lower cholesterol and prevent atherosclerosis. Lactose
is a simple sugar that is present in all milk, and which is
digested with the help of the enzyme lactase. The majority of
humans stop producing significant amounts of lactase before
the age of five. Lactose intolerance is the condition when an
adult does not produce lactase. Consuming too much lactose
will result in excess gas production and diarrhea. An adult
with lactose intolerance, quite a large percent of the
population, can safely drink up to 8 oz. of milk a day.
Cow's milk allergy is an adverse reaction to one or more
cow's milk products. Very occasionally, the allergy is severe
enough to cause death.
Consumption of cow's milk and its byproducts, such as cream,
butter and cheese, has become a very controversial subject.
Below are the results of several studies, reported in the
American Journal of Public Health, Harvard Nurses Health
Study, New England Journal of Medicine, among many
others, in recent years.
A substantial body of scientific evidence raises concerns
about health risks from cow's milk products. Studies in
various countries show a strong correlation between the use
of dairy products and the incidence of childhood diabetes.
Several reports link insulin-dependent diabetes to a specific
protein in dairy products. This form of diabetes usually
begins in childhood.
There is a longstanding theory that cow's milk proteins
stimulate the production of the antibodies which destroy the
insulin, producing pancreatic cells. Researchers from Canada
and Finland found high levels of antibodies to a specific
portion of cow's milk protein, in 100% of 142 diabetic
children they studied. Non-diabetic children may also have
such antibodies, but at much lower levels. Antibodies can
apparently form in response to even small quantities of milk
products, including infant formulas.
Overweight individuals who drink milk may benefit from
decreased risk of insulin resistance and type 2 diabetes.
Full fat milk is rich in saturated fat and cholesterol, which
numerous sources have suggested as contributing to the
increased risk of atherosclerosis and coronary heart
disease.
Babies under the age of 12 months should not be given
cow's milk.
Consumption of milk is reported to increase the risk of bone
fractures, due to animal protein's effect of intensifying
urinary calcium excretion. It is because of this that milk
may, in fact, contribute to osteoporosis, rather than
preventing it. Indeed, in a study which followed 78,000 women
for a twelve-year period, it was found that women who drank
three glasses of milk a day, had more fractures than those
who rarely drank milk.
A multi-country study found that many women with osteoporosis
were lacking in vitamin D: Vitamin D works together with
calcium, to build and maintain strong healthy bones. It helps
the body to absorb the calcium, and milk is an excellent
source of vitamin D. Researchers who followed women who
participated in a health study throughout their pregnancy
found that those who limited their milk intake to one glass
of milk a day, or less, gave birth to babies who weighed
significantly less than those who drank more milk.
There are findings for milk and against milk. You will lose
weight, you will gain weight. It promotes risks of cancer, it
reduces the risks of cancer. Nowadays, when the most
ridiculous pieces of research are funded by sponsors or by
public money, one can prove or disprove most theories. We,
who are trusting, believing Jews, have to use our common
sense, and not go to extremes.
Naturally, if there is a medical condition which prevents us
from using milk products, we will avoid them. A mother who is
able to nurse her baby for a full year, may well be giving
him a good start in life. However, she does not have to go
into a decline if her milk is inadequate for him as he grows.
As always, we have to pray that Hashem will help us to make
the right decisions both in the way we feed our children, and
what we ourselves ingest.
