October is Breast Cancer Awareness Month. Breast Cancer statistics are shocking. It is hard not to know someone who has been affected by this dreaded disease. We must ask ourselves what more we can do to avoid this awful, and far too common disease.
Something that is rising to the forefront of people’s minds is whether deodorant has a role to play in breast cancer. Could your deodorant be affecting your body, and encouraging the growth of cancerous cells?
The following article taken from the Breast cancer UK website. This study provides some insight as to why Pure Beginnings do not include aluminium in the form of aluminium salts in their products, and in particular Pure Beginnings deodorants.
The Pure Beginnings deodorants are aluminium free. They rather use sodium bicarbonate, which is a natural deodoriser. The deodorant targets the bacteria that causes body odour by eliminating their ability to break down sweat.
Aluminium salts as antiperspirants
Antiperspirants use ingredients collectively known as “Aluminium salts”. These may be referred to as any of the following:
- aluminium chloride
- aluminium chlorohydrate
- “rock salts”
- “potassium alum” (potassium aluminium sulphate)
Aluminium salts act by blocking sweat ducts under the arm. This prevents sweat from escaping onto the skin surface. Thereby reducing the moist environment in which odour-causing bacteria multiply. (1)
The use of aluminium salts in antiperspirants has caused debate among scientists. Some epidemiological studies demonstrate their use may potentially increase breast cancer risk (2 & 3), whilst others do not (4).
Aluminium salts and breast cancer
The daily use of underarm antiperspirant has led to higher levels of aluminium in other regions of the breast, when compared to inner regions (5). This is also where many breast cancers start. However, this alone, is not enough to prove a link between aluminium salts and breast cancer.
Whilst a direct causal link has not been proven, recent opinion has questioned the ascribed safety of using aluminium salts in underarm cosmetics. (6)
Some in vitro studies have found that exposure to aluminium salts may cause cells to change in a way that may make them more susceptible to cancer. In other words, aluminium salts may not directly cause cancer. However, they may make the cells more vulnerable to a tumour developing. For example, one study found that human breast cells exposed to aluminium chloride when injected into mice resulted in tumour formation, whereas unexposed cells did not (7).
Other studies have found aluminium chloride and aluminium chlorohydrate made breast cancer cells more motile (i.e. capable of moving around the body) (8 & 9). This is concerning because mortality from breast cancer is mainly associated with tumour spread, which depends on cancer cells developing motility.
Another study found long term exposure to aluminium chloride at environmentally relevant concentrations (those encountered daily) could cause cultured animal mammary cells to become cancerous (10). Aluminium has been measured in breast tissue (11) and breast cysts (12) at higher levels than in present in blood.
Aluminium can act as an oestrogen mimic
Another reason for concern is because aluminium chloride and aluminium chlorohydrate can act as “metalloestrogens”. These are capable of interfering with oestrogen action and under some conditions stimulate responses associated with oestrogen (13).
Natural oestrogen performs a function in the body that leads to rapid cell multiplication. Anything that accelerates the rate of cell division (and DNA copying) also increases the likelihood of mutations occurring. Over time, mutations accumulate, and their combined effects may lead to cancers. Anything that is able to mimic the action of oestrogen may therefore also increase risk of mutations and cancer.
A recent in vitro study (14) found aluminium chlorohydrate causes an increase in levels of a protein known as oestrogen receptor alpha, in oestrogen receptor positive breast cancer cells. This effect resulted in increased expression of genes that regulate breast cancer development and progression.
What is the regulatory position?
The EU has published a statement of caution: Antiperspirant should not be applied to damaged or irritated skin (15). Yet it is common to shave the underarm area before applying antiperspirant. The German Regulatory Agency, BfR, advises women not to shave before applying antiperspirant as they may exceed the weekly tolerable intake of aluminium to the body (16).
In 2014 the EU’s Scientific Committee on Consumer Safety (SCCS) conducted an assessment of aluminium in antiperspirants. They found there was no indication that these increase the breast cancer risk. They, however, acknowledged gaps in scientific data which impeded risk assessment. Currently, the SCCS is revising its assessment and the opinion will be published in 2019. Concerns about the possible link between aluminium salts-containing antiperspirants and breast cancer have led the Swiss National Council to consider a ban or else mandatory warning labels on all aluminium-containing antiperspirants (17).
Should I stop using antiperspirants containing aluminium salts?
Scientific evidence linking the use of underarm antiperspirants to breast cancer is inconclusive. A systematic review which aimed to estimate risk of deodorant/ antiperspirant use for breast cancer concluded; that although there was no evidence of risk, insufficient studies had been undertaken to obtain reliable results.
A study published more recently, which examined self-reported underarm cosmetic product use and breast cancer diagnosis, did find an association between long term use of underarm cosmetics and increased breast cancer risk. As this brief shows, there is clearly some research that supports taking a precautionary approach.
If you have concerns about aluminium salts in antiperspirants, rather choose products which are deodorants and are labelled “aluminium-free”.