| Elizabeth
Connock B.Sc (Hons)
COSMETICS AND TOILETRIES MANUFACTURE WORLDWIDE 2005, pp. 39-41
Honey is arguably the oldest skin care ingredient still in use.
Its healing properties when applied to burns would have been discovered
by earliest man; its skin softening properties by his partner.
Honey-bees probably originated in tropical Africa and spread from
South Africa to northern Europe and east into India and China. They
were brought to the Americas with the first colonists and are now
distributed worldwide. The first bees appear in the fossil record
in deposits dating back about 40 million years in the Eocene. About
30 million years ago they appear to have developed social behaviour
and structurally are virtually identical to modern bees.
Field bees fly from flower to flower and with their tongues suck
out the nectar and store it in sacs within their bodies. After filling
their sacs they return to the hive and regurgitate the stored nectar,
which is mostly water and sucrose, into the mouths of house bees.
The house bees transfer the nectar to the honeycomb cells and in
so doing add enzymes from their bodies to the nectar. The enzyme
invertase converts most of the sucrose into two six-carbon sugars,
glucose and fructose. A small amount of the glucose is attacked
by a second enzyme, glucose oxidase, and is converted into gluconic
acid and hydrogen peroxide. The gluconic acid makes honey an acid
medium with a low pH that is inhospitable to bacteria, mould and
fungi. The hydrogen peroxide gives short-range protection against
these same organisms when the honey is ripening or is diluted for
larval food. By fanning the open cells with their wings the bees
also reduce the moisture content of nectar from about 80% to less
than 20% which gives it a high osmotic pressure and protection against
microbes.
Bees also collect pollen, which is their sole source of protein,
and resins from trees in order to form propolis, which is used to
seal the hive. Propolis is essentially composed of 50% to 55% resin
and balm, 25% to 35% wax, 10% essential oils, 5% pollen and 5% various
organic and mineral substances. Small quantities of pollen and propolis
become associated with honey in the comb and provide some of the
lesser ingredients.
Honey is essentially composed of 20% water, 38% fructose, 31% glucose,
1.3% sucrose, 8.4% acid compounds, 0.8% proteins and 0.5% mineral
salts. It also contains amino acids, vitamins such as biotin, nicotinic
acid, folic acid, pantothenic acid, pyridoxine and thiamine, the
enzymes diastase, invertase, glucose oxidase and catalase and the
mineral content may include potassium, iron, magnesium, phosphorus,
copper and calcium. Its actual composition varies according to the
flowers providing the nectar, the soil on which they grow and the
seasons.
The sugar content affects the propensity of honey to crystallize.
Honey granulation depends on its chemical composition. Because of
its low solubility, glucose precipitates out as crystals of melezitose.
However acacia honey has a higher proportion of the more soluble
fructose so precipitation is less likely. Using acacia honey in
cosmetic preparations significantly reduces the risk of crystal
formation within the product.
Honey exhibits pronounced microbial activity against most pathogenic
bacteria and fungi regardless of their susceptibility or resistance
to different antibiotics. The antimicrobial activity of honey was
attributed to its high sugar osmolarity and low acidity, but honey
has been shown to have stronger antimicrobial activity than corresponding
sugar concentrations with similar pH. The antimicrobial activity
has also been attributed to the enzymatically liberated hydrogen
peroxide activity known as inhibine. Honey dressings have proven
superior in the treatment of superficial wounds and burns, with
patients experiencing increased wound sterilization, earlier healing,
more pain relief and less irritation without allergies and other
side effects often experienced during conventional healing processes.
Honey also appears to promote rapid wound debridement, replacement
of sloughs with granulation tissue and rapid epithelialization and
absorption of oedema from around the margins. These properties make
it a suitable ingredient for skin care.
Honey has keratolytic properties and is used in facial radiance
enhancing products and in anti-wrinkle preparations, alone or in
association with alpha-hydroxy acids, where it improves performance
while reducing irritation.
Formulation 1 is a suggested starting point for a simple cream
with keratolytic action to improve the complexion. Vegetable oils
may be substituted for part or all of the paraffinum liquidum..
A suitable antioxidant such as tocopherol will then be required.
For a stronger keratolytic action 1% of lactic acid or glycolic
acid can be added and the composition buffered to pH 5 by the addition
of 1% sodium citrate.
A liquid anti-wrinkle preparation is shown in Formulation 2. As
with Formulation 1, a vegetable oil with an antioxidant may be used
in place of the paraffinum liquidum. 2% honey is sufficient to provide
a keratolytic action in both formulae. It is thought that the action
is due to an enzyme in honey digesting the dead skin cells.
To be effective as a skin care additive honey needs to be used
at 2% or above but honey is typically used at low levels in cosmetic
products because of difficulties in formulating with it and an undesirable
stickiness associated with the presence of a high level of solubilized
polysaccharides. However it is possible to formulate elegant skin
care products with very high levels of honey and without undesirable
stickiness.
Anhydrous preparations can contain as much as 70% honey and still
be pleasant to apply. The balance is a mixture of oils and waxes
and the presence of a low HLB emulsifier is required. Honey is mixed
at about 40°C with an oil base selected to suit the intended
application and to control the thickness, the spreading and the
stickiness of honey. A suggested starting combination is 20% by
weight of olive oil plus 5% beeswax and 4% sorbitan sesquioleate
with 70% pure acacia honey. The mixture is heated just high enough
to melt the beeswax in the olive oil and then the honey is stirred
in and the mixture stirred while cooling. The result is fluid enough
to apply directly to the skin. It is also possible to emulsify the
mixture with water and preservatives. Fragrance and colour are then
incorporated as required.
There is a wealth of information available regarding the use of
honey in wound healing, in the treatment of skin disorders and in
treatments for acne, dandruff and other scalp disorders. There are
also many interesting patents including USP 6,174,535, which describes
a honey gel based on glyceryl polymethacrylate and cyclopentasiloxane.
Approximately 70% acacia honey is mixed with 5% cyclopentasiloxane
and the balance is Lubrajel CG, a glyceryl polymethacrylate/propylene
glycol composition available from United-Guardian Inc.
USP 6,171,604 describes the use of honey preparations for the treatment
of acne in which twenty-seven teenagers suffering from this condition
applied a salve containing honey twice a day and all lesions were
cleared within three weeks. Also scarring from earlier eruptions
was noticeably reduced. The successful treatment of herpes, of wounds,
of skin rashes and of contact dermatitis is also described.
An interesting combination of essential oils with honey is described
in USP 6,623,767. It is claimed that this combination can be used
in skin treatment and care products such as moisturizing, anti-wrinkle
and slimming creams; in hair cleaning and hair care products such
as shampoos; in soaps; in dental and mouth care products such as
toothpaste, and in hydrotherapy products for baths.
While A & E Connock does not advocate ignoring patent rights,
patents are useful for providing background information and for
claims substantiation. It is also difficult to understand how the
patents would stand up against claims of prior art when they describe
the use of a material that has been in use for so long but all formulators
are advised to seek expert advice before proceeding with a product
similar to that described in a patent.
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