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Monday, 28 November 2011

Chemicals in our Make up - Part 1: Foundation

10 Sexy People gave their opinion
This post was a request from Bibil, and inspired by one of my earlier posts about Eczema and cosmetics products:

What are the chemicals in our make up?

Well, although I found many articles saying that there is no regulation, actually there is a fairly well controlled organisation that bases its research on many reviews published in scientific journals.

Because the subject is endless and for the sake of easy reading, I will concentrate on the essentials such as: Foundation - Eye shadow - Mascara - Lipstick which I will separate into different posts, making it a mini series. Today's post will be:

Liquid foundation makeup

Foundation is composed of different phases that are mixed together:
The Powder Phase products includes skin covering and opaque materials such as titanium dioxide and/or zinc oxide, and fillers such as talc or mica that creates a matte finish on the skin. Also, metallic stearates are added to provide opacity and water repellency.
Titanium dioxide TiO2 is a natural mineral used, amongst many other applications, as a pigment because of it brightness and also its efficient opacifier! It is also used in every sunscreen product for its ability to protect the skin, however titanium dioxide dust, when inhaled, has been classified as a cancer-causing agent. This follows a study on rats developing lung cancer and mice getting mutations in their DNA. 
Talc, also called magnesium silicate, is considered safe at a low concentrations, but many studies have shown a link between talc and lung/ovarian/skin cancer. In general, inhalation of the particles are what's harmful.
Mica is a general name for silicates, they are used in combination with TiO2 to produce shimmering effects. They are also used in paint for cars and plastic containers. 
Metallic stearates such as Magnesium stearate doesn't seem to yield any risk.

The Aqueous Phase includes mostly water followed by wetting or dispersing agents that assist in pigment blending (lecithin, sulfosuccinates, ethoxylated sorbitan esters). Also gums and clays that operates as co-emulsifiers, thickeners and pigment-suspending agents (Magnesium aluminium silicate, bentonite, methylcellulose).
Lecithin is a natural product that we can find in egg yolk, and has even been proven to help lowering cholesterol.  
Sulfosuccinate is commomly used in pharmaceuticals products, rare side effects have been linked to its comsumption. Sulfosuccinate does not cause cancer, but has been shown to be a skin and eyes irritant.  
Ethoxylated Sorbitan ester is a solubilizer, an emulsifier, an antistat and fiber lubricant used in textile industry, a wetting agent, a viscosity modifier, a suspending agent used in food, cosmetics, drugs, textile and metal working industries, a solubilizer for perfumes and flavours, insecticide, herbicides, paints and inks, and pharmaceuticals. It is found naturally in various berries and fruits or it is prepared synthetically by high-pressure preparation of sugar. Studies found it to be safe and non carcinogenic. See this Study for more info   
Bentonite can be used in cement, adhesives, ceramic and cat litter. Studies have not found it to be toxic at the low doses used in cosmetics. An interesting fact from Wikipedia that we can somehow relate to foundation: The same effluvial deposition of bentonite clay onto beaches accounts for the variety of plasticity of sand from place to place for building sand castles. Beach sand consisting of only silica and shell grains does not mold well compared to grains coated with bentonite clay. This is why some beaches are much better for building sand castles than others. 

The Polyol Phase consists of materials that improve makeup spreadability, decrease drying rate, increase product smoothness and creaminess (glycerin, PEG).
Glycerin is the same as Glycerol.It is a colorless, odorless, viscuous liquid that is widely used in pharmaceuticals formulations.It is found in allergen immunotherapies, cough syrups, elixirs and expectorants, toothpaste, mouthwashes, skin care products, shaving cream, hair care products,soaps.Topical pure or nearly pure glycerol is an effective treatment for psoriasis, burns, bites, cuts, rashes, bedsores, and calluses. 
PEGs: These compounds are used in a great variety of cosmetic applications because of their solubility and viscosity properties, and because of their low toxicity. They produce little or no ocular or dermal irritation and have extremely low acute and chronic toxicities. They do not readily penetrate intact skin, and in view of the wide use of preparations containing PEG and PEG derivatives, only few case reports on sensitisation reactions have been published, mainly involving patients with exposure to PEGs in medicines or following exposure to injured or chronically inflamed skin. On healthy skin, the sensitising potential of these compounds appears to be negligible.

The Oil Phase is composed of both liquid and solid materials that assist with product emulsification, spreadibility, pigment dispersion and viscosity control. They include fatty acids (stearic acid, oleic acid), waxes (carnauba, ozokerite, ceresin) and paste like butters. Emulsifying and thickening agents (propylen glycol, sorbitan), along with antioxidants (tocopherols, BHT), preservatives (parabens, urea), and fragrances added within the oil phase, may improve application properties and product quality and purity.
Stearic/oleic acid:  The term "oleic" is related to oil or olive. Oleic acid is a fatty acid found in various animal and vegetable fats. Positive health effects of the substance have been documented. Adverse effects also have been documented, however, because both oleic and monounsaturated fatty acid levels in the membranes of red blood cells have been associated with increased risk of breast cancer. Stearic acid occurs in many animal and vergetable fats and oils. And some studies suggest that it may be healthier than other saturated fatty acids. 
Carnauba is used to thicken the formulation of foundation. Is also used in candy making or pharmaceutical tablet. 
Ozokerite is a naturally occurring odoriferous mineral wax or paraffin and is used in candle making. I found one scientific article entitled the carcinogenic activity of medicinal ozokerite, but it is in Russian so I don't know if the result is positive or not! 
Ceresin is a wax derived from ozokerite by a purifying process. 
Tocopherols =Vitamin E activity is an antioxidant added to prevent oxidation of sensitive ingredients as well as protect the skin from free-radical damage. It is found in our diet or in supplements; therefore it is safe to assume that it is safe in cosmetics. 
BHT is an antioxidant, some studies haven shown that it reduces the risk of cancer, others studies to increase it. It is also found in supplements. A Scientific review was conducted in '99 ans concluded that BHA (is used as a "safer" replacement for BHT) and BHT pose no cancer hazard and, to the contrary, may be carcinogenic at current levels of food additive use
Parabens are used as preservatives for their antibacterial and antifungal actions, so we can keep our creams without them becoming infected. So far, no other component has been as efficient to replace it. Much contraversy has been raised  after extremely low concentrations have been found in breast cancer tumours however more research need to be conducted to confidently link paraben to cancer. Paraben is found naturally in some plants such as blueberries and most parabens used in products have the exact same formula. However it has been shown with confidence that some people can become allergic to it and should avoid it or else could develop dermatitis!  - Full review is now available 
Urea is a skin irritant for people who suffers from dermatitis and have an allergy to Formaldehyde.

For more info, check this list of scientific reviews HERE

This concludes our first part of Chemicals in our Make up. I hope you found it interesting. 

Sunday, 6 November 2011

Vitamin D and the Winter Blues

8 Sexy People gave their opinion
This was a request from Bibil: Why do we feel depressed during winter?

Winter blues, called SAD for Seasonal Affective Disorder, is a seasonal depression and mood variation known to be related to how much sunlight you receive. Your mood is influenced by a complexed relationship between sunlight, melatonin (sleep hormone) and serotonin (awake AND good mood hormone).

Winter Blues 

As the dark hours increase during winter, our body increases levels of melatonin, leaving less hours for the body to increase its serotonin levels. Whereas during summer, serotonin levels increase when you are exposed to bright light making you feel in a better mood!
Indeed it is well known that bright light therapy can bring quick benefits to people with depression or SAD because light affects the balance between melatonin and serotonin

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