This is a summary of an article
which appeared in The South
African Journal of Natural
Medicine 2007, 33, p106-112.

Squalene – antioxidantof the future?
Sourced primarily from the liver of the deep-sea
shark, squalene has been referred to as the‘antioxidant of the future’.1 Heidi du Preez
discusses this unique molecule.

S

qualene is an isoprenoid hydrocarbon with six isoprene units. It is
produced in our bodies and also found in nature. Many
antioxidants are either isoprenoids or have an isoprenoid tail.
Vitamin E, vitamin A, beta-carotene and flavonoids are allisoprenoids. Isoprenoids are found abundantly in nature, but biologists
are mainly interested in studying the few, including squalene andlycopene, that have extraordinary antioxidant properties.
Since squalene is a pure isoprenoid, containing only isoprene units, it
has an effective and stable antioxidant configuration. Squalene isconsidered by many to be the most powerful and stable of theisoprenoids.2
In its purified form squalene is a colourless, almost tasteless,transparent liquid without a significant odour. It is the majorhydrocarbon in fish oils. Since squalene is a polyunsaturated ‘lipid’,
derived from fish oil, it should not be confused with being an essential
fatty acid.

SOURCESThe best source of squalene is the liver of the deep-sea shark. The
dogfish shark produces the highest yield of good-quality squalene.3
The dogfish is a deep-dwelling shark – some swim at depths
exceeding 3 000 m. It is believed that sharks can survive this harshenvironment because of their gigantic liver which makes up
approximately 70% of a shark’s internal organs. This oversized liver
contains between 50% and 70% squalene. Squalene is a source of

HEIDI DU PREEZ is a
professional natural scientist,with a Masters degree infood science. She is currently
studying for a degree innutritional medicine. Heidi
consults for both the foodand health industries. She
uses a holistic, naturopathic
approach, incorporating
diet, supplementation,
detoxification and spiritual
wellbeing in her treatment
regimen. Her focus is on theprevention and cure ofchronic, metabolic anddegenerative diseases. Heidi
serves on the council of theSouth African Association for
Nutritional Therapy, and is
the author of the recipebook Natural Medicine’s
Wholefood Cookbook.
E-mail:heidi@naturalnutrition.co.za& website:www.naturalnutrition.co.za.

1energy for the sharks and allows them to live at these depths and thrive in an environment that is harshand oxygen-poor.
The dogfish is very abundant, and is the most common shark species in the world. While the dogfish is
related to the shark family, it is not on the endangered species list because of its huge numbers.3 Living at
such depths, the dogfish cannot be caught with nets. Instead, it has to be ‘target’ fished with lines. The
use of specific, regulated fishing methods allows for efficient harvesting of the abundant dogfish withoutharming the valuable resources of the sea. Ethical harvesting will ensure its availability for generations tocome. The whole fish is used and processed. The flesh is used for human consumption and the skin is used
for tool pouches – There is no waste.
Vegetable sources of squalene are olive oil and amaranth. Many ancient
Mediterranean cultures believed that olive oil increases strength and longevity, andindeed the olive tree is a rich source of squalene. Extra-virgin olive oil however only
contains about 200 - 450 mg squalene per 100 g oil.4

HISTORY
Squalene was first found in the human body in the 1950s, when the cholesterol metabolism was first
identified. Squalene is one of the intermediate steps in cholesterol metabolism. More recently, squalene
was found to be abundant in the skin, the membranous lining of the gastro-intestinal and respiratory
tracts, and in adipose tissue (fat).
Research avenues opened in 1963, when an article in the scientific journal Nature demonstrated thatsqualene stimulates macrophages – the principal immune cells in the inner and outer protective coat ofour bodies.7 In 1982 squalene’s detoxifying function was demonstrated in several research experiments 8
and in 1993 its radio-protective effects were revealed.9 These discoveries set the stage for the medicinaluse of squalene. In 1995 a Japanese research team clearly demonstrated that squalene can prevent UVinduced oxidation of lipids in skin,10 a key finding that finally placed squalene in the scientific spotlight.
In 1996 a human clinical trial of squalene was performed to examine its effectiveness in lowering blood
cholesterol.11 As a result of these and subsequent research studies, dietary squalene has been found to:






Exhibit superior antioxidant properties.2
Increase the efficiency of the immune system.2,7,12
Inhibit cancer growth.13
Enhance the anti-tumour action of chemotherapeutic agents.14
Lower blood cholesterol – a fall in LDL levels accompanied by a rise in HDL concentration isparticularly remarkable.11

SUPERIOR ANTIOXIDANT
Oxygen is the great forgotten nutrient. Lack of it has been pinpointed as a cause of, or contributing
factor in, nearly all degenerative diseases. Squalene is the closest thing we have to an oxygen
supplement.15 It facilitates oxygen delivery throughout the body.3
Another threat to our cells that is causing disease states such as cancer, atherosclerosis, arthritis, diabetes,dermatological system disorders, cataracts and other age-related diseases is free radicals. They are
unstable molecules with unpaired electrons. Free radicals are produced constantly within- and outside
the cell, some as by-products of energy-releasing oxidation in the mitochondria, others by UV light,
radioactivity and the metabolism of drugs and chemicals. Inhalation of cigarette smoke and exposure to
air pollution is also accompanied by an increased production of free radicals.42Each cell possesses its own defence mechanism – the antioxidant defence system – that maintains a
dynamic internal balance between free radicals and antioxidant nutrients. Antioxidants neutralise free
radicals. Increased generation of free radicals can lead to oxidative stress, producing imbalance andresulting in oxidative damage, cell death, tissue damage and disease. However, there is also growing
evidence that having too many antioxidants is just as harmful as not having enough. In fact, our body as
a whole must maintain a proper balance between oxidants and antioxidants. Our focus should therefore
not be to take as many antioxidants as possible but to help the system maintain its oxidant-antioxidantbalance. It alone knows its precise needs, and therefore endogenous antioxidants (those synthesised in
the cells) will play a greater role in oxidant-antioxidant balance than exogenous (dietary) ones. Cell andtissue damage caused by oxidant-antioxidant imbalance is referred to as oxidative damage. The firststep in this damage process is the lipid peroxidation chain reaction,
which breaks down cell membranes.2
Squalene is an excellent antioxidant because of its great capacity toreceive or donate electrons without suffering molecular disruption.
Squalene’s very low ionisation threshold accounts for its very large
capacity to donate electrons, like vitamin E. This unique stability is the
key to squalene’s ability to terminate a lipid peroxidation chain
reaction. According to laboratory research, this happens specificallyin the skin’s surface.10 It is reasonable to assume that it performs asimilar function wherever it is found, for example within individual cells
and in the biomembrane.2
It is commonly believed that vitamin E is the principal antioxidant of lipid peroxidation chain reactions in
the biomembrane, but this may not be the case after all. The comparison in Table I proves that theusefulness of vitamin E as the primary antioxidant in the biomembrane may be exaggerated, and the role
played by squalene may be more significant.
Table I. Comparison of vitamin E and squalene2
Vitamin E
A mixed isoprenoid of three isoprene units with very
good antioxidant capacity
Exogenous (dependent on dietary sources) andnot necessarily available when needed
Cannot be synthesised in the body – available onlyin certain foods
Limited integration into the biomembrane, where it
becomes embedded in the lipid bilayers
Is fixed in the lipid layer and cannot move freely
Too many vitamin E molecules alter thebiomembrane’s physiological properties andstructural configuration
Requires recycling by endogenous antioxidants
such as glutathione and squalene
Is itself susceptible to free radical attacks
The usefulness of vitamin E as the sole terminator in
the biomembrane is limited

Squalene
A pure isoprenoid of six isoprene units with very
good antioxidant capacity
Endogenous (manufactured on demand) andreadily available under normal circumstances
Manufactured within the cell from readily available
glucoseStrongly attached to the hydrophobic band
between the two lipid layers of the biomembrane,
where risk of lipid peroxidation is greatest
Can move freely throughout the biomembrane
Large quantities do not alter the physiologicalproperties of the biomembrane
Does not require recycling
Relatively resistant to free radical attacks
The role played by squalene as a terminator in thebiomembrane is significant

3

IMMUNE RESPONSE
Experimental studies have shown that squalene-supplemented dietslead to increased performance of the immune system. Laboratory
studies have confirmed that squalene enhances the function ofmacrophages.7,12,16 Evidence suggests that the immune cell’sbiomembrane is protected against oxidative stress by squalene during
phagocytosis.2 Squalene exhibits anti-viral, anti-fungal and antibacterial properties.3

CANCER TREATMENT AND PREVENTION
Various epidemiological and laboratory data suggest that squalene may help prevent cancer and canalso fight established tumours. Because it combats cancer at the earliest stages, squalene’s preventive
and therapeutic possibilities are extremely promising. Squalene’s powerful antioxidant andcytoprotective effects are very significant. A research team from Toronto’s Hospital for Sick Children
demonstrated that squalene has selective cytoprotection in in vitro and in vivo models.17,18
Through extensive research, squalene has further been shown to:








Prevent the occurrence of certain cancers.19-29
Prevent carcinogenic agents from inducing cancer due to its detoxification properties and its ability
to prevent activation of the ras oncogene.2,19,22,30-33
Protect cells from the effects of radiation,9,34,35 which makes it a suitable protector of healthy cells
against cancer radiotherapy.
Act directly against cancer tumour activity.36,37
Optimise the activity of chemotherapeutic agents.11,23,32

The strong detoxification properties of squalene are very promising. Because it is a lipid, it detoxifies
lipophilic (fat-soluble) poisons, which the body finds much harder to deal with than water-soluble poisons.
Four independent researchers have tested the detoxifying abilities of squalene by measuring the extent
to which squalene helps cleanse laboratory animals of xenobiotics.8,38-41 (Xenobiotics – Manmadechemicals/pollutants. For example, burning plastics and certain fertilizers produce a chemical called
dioxin, a xenobiotic toxin so pervasive, it can be found in virtually every human being alive today).
Although the detoxifying mechanism is still not clearly known, it is thought that squalene may possibly
increase the mobilisation of lipid-soluble xenobiotics enabling elimination through the intestine. Also,
when xenobiotics accumulate in fat cells, stored squalene may be released into the general circulation,
stimulating bile flow and enhancing xenobiotic elimination.2

HEART DISEASE
These days we are so intent on keeping cholesterol levels down that we seem to have forgotten that acertain level of cholesterol is essential to health. Cholesterol is manufactured in individual cells in acomplex series of biochemical steps known as the mevalonate pathway. Glucose is first converted intomevalonic acid, and this in turn produces three isoprenoids – geranyl, farnesyl and squalene. Some twodozen steps later, the cell has a supply of cholesterol, essential for the manufacture of hormones and bilesalts.
Cynics might be concerned that since squalene is one of the very ingredients that the body uses tomanufacture cholesterol, dietary squalene might elevate cholesterol levels. However, research suggeststhat squalene actually lowers high blood concentrations of cholesterol and triglycerides,11,15,42,43

4

apparently by increasing the liver’s filtering capacity. Cholesterol elimination in the faeces increases
parallel to a rise in squalene levels. These laboratory findings are supported by epidemiologicalcorrelations of squalene-rich olive oil consumption with a low incidence of coronary heart disease.44

SKIN HEALTH
Squalene is found abundantly in the skin, where it acts to protect against free radicals. In a chemical
quenching reaction of free radicals, the squalene molecule incorporates the radical chemically,
producing squalene hydroperoxide – a new molecule. Squalene hydroperoxide is not an antioxidant but
it is an excellent emollient that, in skin, serves as a natural sunscreen and moisturiser. 2 Squalene has theability to provide relief, and protects, nourishes and restores harmony to dry, sensitive skin.
Squalene can also be used topically, where it can help to heal wounds, help prevent scarring, andprovide a natural and very effective moisturiser. Squalene keeps skin smooth and supple, preventing finelines and wrinkles. Squalane is a synthesised form of squalene, which is used in cosmetic applications
because of its greater stability.
Unlike the internal mucosae, the skin is subjected to direct sunlight, which includes UV-B radiation, asource of free radicals and potential skin damage. Various research studies substantiate squalene’s rolein protecting skin from UV radiation.47,48 This may help explain why sebum contains such a high proportion(12%) of squalene.45,49

WHY DO WE NEED SQUALENE?
Rising levels of oxidative stress in our environment – due to ozone depletion, increased backgroundradiation, UV exposure and accumulation of xenobiotics, carcinogens and other chemicals – puttremendous pressure on the squalene metabolism in the body. Metabolic response of squalene to thisstress is an increased synthesis and consumption of endogenous squalene, beyond the body’s ability tocope, with adverse consequences. In the short-term, we can expect an increase in all kinds of cancers,
and a generally weakened immune response. The long-range prognosis includes
accelerated aging, decreased fertility and changes in psychological behaviour.
As a person ages, the distribution and concentration of squalene changes. It ismostly secreted up to and around age 20. At age 25 the secretion of squalene
gradually decreases. This is one of the reasons why our skin becomes dry andwrinkled as we age. Due to the increased threat of oxidative stress in ourenvironment and accelerated aging, exogenous sources of squalene prove tobe imperative.
Squalene’s antioxidant nature, its immune-stimulant action and its ability toprotect cellular structures and improve cellular repair response should be enoughreason to take squalene.
Further benefits of taking squalene include:






Increased stamina and energy.
Improved digestive health due to the increased production of bile acids. Normalisation of bothconstipation and diarrhoea and effective in the treatment of gastritis.
Balancing of hormone levels through its involvement in the production of steroid hormones, resulting inincreased sexual vitality, improvement in premenstrual syndrome, menopausal problems and evenfertility.
Improved action of a number of pharmaceutical drugs, to the extent that lower doses achieve thesame results.
Minimisation of the side-effects of drugs through its detoxifying action.

5





Improved and facilitated healing of damaged articulation cartilages, therefore useful in cases ofosteoarthrosis and sport injuries.
Vibrant hair, nails and skin through squalene’s ability to rejuvenate and activate cells.
Beneficial effects on various eye disorders.3,50

SQUALENE AS DIETARY SUPPLEMENT
Squalene supplements have been widely tested for toxicity 3 and there is considerable proof thatsqualene is non-toxic. However, not all the squalene dietary supplements on the market are safe. Somehave been found to contain PCBs (Polychorinated Biphenyls are persistent organic pollutants – causing
endocrine disruption and neurotoxicity. PCB’s have been used in coolants, lubricants, adhesives, paints,etc.), heavy metals and other carcinogens. Many of the so-called squalene supplements offered on themarket are actually raw shark liver oil. They have considerably lower levels of squalene content. It is very
important to take only 100% pure and natural extracted squalene that is standardised and certified.
Squalene is safe as long as it is carefully extracted through highly specialised distillation processes and apurity of 99.9% is maintained at every stage of production. The end product should contain not less than
99% squalene. In Japan, top squalene manufacturers are directly involved in the whole process, fromfishing operations right through to marketing of the end-product. This ensures supply consistency, productquality, as well as flexibility in storage which remains a vital part in the whole process. Squalene iP6 has
been endorsed by many reputable health professionals and research laboratories around the world forbeing superior in quality.
The usual recommended dose of squalene is two (450 mg) capsules per day, taken
on an empty stomach. Anyone suffering from illness or infection may temporarily
increase their dose to 6 or 8 capsules a day. Children and infants can safely takesqualene at a dose of 1 capsule per day, which can be increased to 2 capsules
daily during illness. Squalene is also safe and very beneficial to take during
pregnancy. For cancer patients, 2 - 4 g of squalene is usually recommended. It isadvisable to take squalene under the care of a qualified health practitioner.

CONCLUSION
While squalene may be very beneficial, it is by no means a ‘cure-all’. No one substance or ‘magic pill’
can bring about health. Optimum health is only achieved through a healthy lifestyle, i.e. a balanced
whole-food diet, a healthy environment, exercise, rest and spiritual development. The answer to good
health is ‘prevention by anticipation and not by reaction’.
Squalene is more than just a superior antioxidant. It has an adaptogenic effect, balancing hormones,cholesterol and oxygen levels. It supports the innate healing processes of the body. This unique molecule,with its indisputably rich past, has a great future in preventive therapy and integrative medicine.
End of Article

6

PETdiatric Laboratories Squalene AKG

Dosage and Usage.

Petdiatric Laboratories Squalene AKG is formulated and best for increasing
your pets immune system. It is aim at reducing the symptoms of allergies
caused by allergen and malnutrition. It is advice to take Squalene AKG on
daily basis.
Squalene AKG contains high concentration of anti-oxidants; it promotes
growth of new skin cells and increases immune system. It is suitable for catsand dogs.
Pets below 20 kg, should take one softgel every alternate day. For pets
weigh between 21kg and above, it is advisable to intake one softgel perday. PETdiatric Laboratories Squalene AKG is specially price effectively to beenjoyed by all pet’s owners. It merely cost RM1.33per day for a healthy skinand coat.
7

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