Do you know anything about Parabens and how they may cause breast cancer?

Hi Catherine,

Recently the media have been covering the subject of Parabens and how they may cause breast cancer. I noticed that my natural progesterone cream contains parabens. Do you know anything on this subject please?

Thank you,

Jean

Dear Jean,

In our upcoming FREE ebook ‘10 Things You Must Know About Natural Progesterone’ which will be made available shortly, we point out in the clearest possible terms that ingredients like “paraben” , i.e. Methylparaben and Propylparaben should be avoided.

Parabens are the most commonly used preservatives in topical pharmaceutical preparations. They are also used in cosmetics, skin care products, medications, foods, and industrially in oils, fats, shoe polishes, textiles and glues. Two or more paraben esters are often found in the one product so it is useful to test paraben sensitivity with paraben mix, as there is a high incidence of cross-reactions between the esters. Paraben mix sensitivity produces classic allergic contact dermatitis reactions.

The cosmetic industry has widely used parabens due to what they believe to be their ability to reduce the risk of microbial contamination effectively at low concentrations. Parabens are recognized as safe by the World Health Organization as well as government agencies throughout the world. In the United States, the Cosmetic Ingredient Review (CIR) expert panel (an independent body of internationally recognized medical and scientific experts in safety evaluation) has reviewed parabens and concluded they are safe for use in cosmetic products. Importantly, the FDA considers a CIR decision of safety as a significant basis for the use of ingredients in cosmetic products.

More recently, the UK press, and indeed the press world-wide, have been filled with reports of a study that has been claimed to link underarm deodorants and antiperspirants with breast cancer. The research was published in the Journal of Applied Toxicology on 8 January 2004.

A small study of 20 breast cancer tissue samples looked at the amount of a certain set of chemicals that had accumulated in them. The study was looking for the levels of a range of chemicals from underarm deodorants and antiperspirants, known as parabens. The research was carried out at the University of Reading in England on breast cancer tissue samples given by the Edinburgh Breast Unit Research Group. The researchers found that parabens were present in 18 out of the 20 breast cancer tissue samples.

It is known that the female hormone estrogen is a factor in the formation and growth of some breast tumours. This is one of the reasons why breast cancer is more common in women than in men. The researchers who carried out this study argue that parabens work on the body in same way as estrogen and may help breast cancer tumours to grow.

Epidemiology shows that ninety per cent of breast cancers are environmental in origin and linked to a Western lifestyle, but the specific environmental causes have never been identified. Around five to ten per cent of breast cancer arises as an inherited genetic susceptibility, but the question remains as to susceptibility to what? The main identified risk factors relate to lifetime exposure to the female hormone estrogen, through variations in puberty, menopause, childbirth and personal choices such as use of the contraceptive pill or hormone replacement therapy. Diet, smoking and excessive alcohol consumption can also have an effect. However, it is estimated that there remain still seventy per cent of breast cancers unaccounted for by these known risk factors.

Many studies have now shown that a variety of agrochemicals and industrial pollutants can accumulate in body tissues and because many are fat-soluble they can accumulate over a lifetime very effectively in breast fat. Some of these chemicals have now been banned, but as they are highly persistent, they continue to accumulate in breast fat. This occurs over a lifetime but the chemicals can be passed out from the fat during times of dieting or fasting, and can also be passed in the milk to the young during breast-feeding. Many of these chemicals can damage DNA.

However, equally worrying has been the discovery in recent years that some of these chemicals, such as DDT and PCBs, can also mimic the action of estrogen, and estrogen is well known to play a role in development of breast cancer. One might argue that if a cocktail of such pollutant chemicals can between them both damage DNA and mimic estrogen action, then they are all that are needed to give rise to breast cancer. Why are we all so slow to acknowledge that they could be a cause of breast cancer? Yet the will to believe this seems to be very faint.

At the moment, Jean, all that can be said with certainty is that the body absorbs parabens, possibly from deodorants and antiperspirants but possibly from other sources too. It is not possible to say with certainty where these parabens came from - they may not have come from deodorants or antiperspirants but from other household sources. However, in relation to recent studies, the parabens were found in a form that suggests that they entered through the skin. And there is substantial scientific evidence to suggest that increased exposure to substances that behave like estrogen in the body may elevate an individual?s risk of developing cancer. Parabens are among these substances.

For those of our readers who have further questions and would like to write to Dr Philippa Darbre directly here are her contact details:

Dr Philippa Darbre
Division of Cell and Molecular Biology
School of Animal and Microbial Sciences
The University of Reading
PO Box 228, Whiteknights, Reading RG6 6AJ
P.D.Darbre@reading.ac.uk