A new study suggests that high cholesterol increases the risk of breast cancer in women.

Per scientists, a by-product of cholesterol is responsible for propelling the spread and growth of the most common type of breast cancer.

However, according to the study published in the journal Science, scientists reveal that a daily intake of statins (a cholesterol-lowering drug) may help prevent breast cancer. Lowering cholesterol can therefore be a simple yet effective way of reducing the risk of breast cancer.

The current study also explains that a link exists between obesity and breast cancer as the risk of high cholesterol is more in obese women. Previous research too has established a link between high cholesterol levels and breast cancer.

Per the new study, when cholesterol breaks down in the human body it produces a chemical which has a similar effect to oestrogen (female hormone), which in turn speeds up three quarters of breast cancers.

"A lot of studies have shown a connection between obesity and breast cancer, and specifically that elevated cholesterol is associated with breast cancer risk, but no mechanism has been identified," said lead researcher Dr Donald McDonnell, from Duke University in North Carolina. "What we have now found is a molecule called 27HC that mimics oestrogen and can independently drive the growth of breast cancer."

The scientists conducted experiments on mice and discovered that daily injections of the 27HC molecule caused the breast cancers to spread faster. However, when the mice were treated with statins it resulted in the reduction of the cholesterol level, as well the tumor growth.

When tests were conducted by the team on human cells it was found that the most powerful cancers produce a high level of a chemical which propels the production of the 27HC molecule.

"This is a very significant finding. Human breast tumours are making an oestrogen-like molecule that can promote the growth of the tumour. In essence, the tumours have developed a mechanism to use a different source of fuel," said Dr. McDonnel.

The study also disclosed that if one has high levels of cholesterol, then it can block the drug tamoxifen, which is widely used to counter the effects of oestrogen.

Currently, statins are already consumed by several people to help lower their cholesterol levels. However, experts have warned that it is too early to advise women on the intake of statins.

"This study is intriguing as it shows for the first time a direct link between cholesterol and breast cancer in mice - but it's too early to say how this knowledge might help tackle breast cancer in the future," noted Dr Emma Smith, from Cancer Research UK,