Simmentaler Joernaal 2013.indb

Simmentaler - Feed the World
Wetenskaplik | Scientific
70
Is better health possible with
Simmentaler crossbred cows?
The fats in our diet can have a significant impact on
our health status and consist of various components.
Amongst these components, fatty acids have been
extensively researched and are classified according
to their chemical structure, namely the saturate, monounsaturate
and polyunsaturate classes, dependent on
the number of carbon-to-carbon double bonds (Figure
1). The polyunsaturated fatty acids in turn consist of
four families, the omega-9, ( -9 or n-9), omega-7, (
-7 or A-7), omega-6 ( -6 or n- 6) and omega-3 ( -3 or
n-3), determined by the position of the carbon-to-carbon
double bonds. Of these, the omega-6 and -3 families
are essential because they cannot be produced by the
human body and must therefore be provided by the food
we eat. These fatty acids are essential for healthy growth
and development, brain function, blood circulation,
vision, water balance and a healthy immune system.
Research indicates that a balanced intake of omega-6
and -3 fatty acids are essential for the human body’s
health. Currently our “Western diet” mostly consists
of the omega-6 fatty acids, disturbing the balance
between the two fatty acid families. This imbalance
has been associated with certain diet-related diseases,
such as an increased risk for heart attacks and strokes,
hypertension, depression, cognitive problems, certain
inflammatory diseases (i.e. arthritis) and certain skin
conditions and cancers. A higher intake of omega-3
fatty acids can protect people against many health
risks and therefore have a favorable effect on these
diseases, such as a reduction in blood cholesterol
Research indicates that
a balanced intake of
omega-6 and -3 fatty
acids are essential
for the human body’s
health.
levels. The omega-3 fatty acids can strengthen the
immune system and protect against many diseases,
including Alzheimer’s disease.
Omega-3 fatty acids is a collective name for several
fatty acids, including alpha-linoleic acid (ALA),
eicosapentaenoic acid (EPA) and docosahexanoic acid
(DHA), found in natural food commodities and derived
products. ALA is present in certain nuts such as walnuts;
seeds such as pumpkin and linseed/flaxseed; oils such
as canola and linseed/flaxseed oil, and some fruits
and vegetables such as broccoli, cantaloupe, spinach,
Chinese cabbage and cauliflower. EPA and DHA are
found in fish (herring, mackerel, sturgeon, anchovies/
sardines, tuna) and fish-derived oils such as salmon oil.
The dietary recommended intake for EPA and DHA is two
to three servings of fish per week.
The most common omega-6 fatty acids are linoleic acid
(LA) and arachidonic acid (AA), found in foods such as
eggs, red meat, poultry, cereals, certain vegetable oils
(especially corn, safflower, sunflower and sesame oils),
fried foods and some margarines. This fatty acid family
is very abundant in the Western-style diet. Conjugated
linoleic acid (CLA, Figure 2), naturally derived from LA by
bacteria in ruminants such as cows, is associated with
improving health and weight loss.
Monounsaturated fats, mainly represented by the
omega-9 fatty acid family, are also considered as good
because they have no adverse effect on a person’s health
and may have a beneficial effect on the cardiovascular
system. Olive oil, which consists of 80% oleic acid, is at
the top of the list of healthy monounsaturated fatty acids,
together with avocados. The best olive oil with regards
to flavour and nutritional value is cold-pressed and
unrefined, also known as the extra virgin olive oil type,
and is from a single source and not mixed with other
types of oils.
Saturated fatty acids, widely regarded as unhealthy
and to be avoided, are found in animal fats (fatty meat
products, processed meat), coconut and certain palm
oils, also used in many commercially made biscuits
and crackers. However, research has shown that not all
foods that contain saturated fatty acids are unhealthy.
Epidemiological studies indicate that milk, with a 60%
saturated fatty acid content, is not associated with heart
disease. Instead, milk can be regarded as an important
source of vitamins and minerals such as vitamin A, B2,
B12, D and K and calcium and magnesium.
Commercial trans fatty acids, related to the saturated
fatty acids by chemical effects in the human body, have
been associated with an unhealthy life-style and can
contribute to cardiovascular disease. These fatty acids
are present in hard margarines and over utilised cooking
oils. They are also artificially produced from natural
polyunsaturated fatty acids in the production of certain
foodstuffs, such as biscuits and pastries, to provide food
stability for a longer shelf life. Legislation in South Africa,
however, regulates the levels of these fatty acids in food,
and caters to replace them with healthier alternatives.