Women have been warned to limit their alcohol consumption to just six drinks per year – as any more has been found to significantly increase cancer risk.
New estimates show that drinking more than this annually can raise a woman’s lifetime risk of developing the disease by up to 27 per cent.
By comparison, sticking to six or fewer drinks a year increases risk by just 0.3 per cent – a negligible figure, according to experts.
Breast cancer is the most common form of cancer in the UK, with around 55,000 women diagnosed each year. Around 11,500 die from the disease annually.
While it has long been established that even low levels of alcohol intake carry some danger, researchers at the World Health Organisation have now determined the level of risk associated with each glass of wine consumed.
Just one drink per week is associated with a three per cent increase, while more than six glasses per year pushes that up to two per cent.
A small glass of wine daily – around 10 units per week – raises the risk by 15 per cent.
At the higher end of the scale, a large glass of wine per day, or about two bottles a week – or 20 units – increases the risk by 27 per cent, meaning 14 in 100 women who drink at that level can expect to develop the disease.
Dr Liz O’Riordan, a breast cancer specialist who has had the disease three times, wonders if drinking in her 20s (pictured) may have increased the likelihood that she would develop cancer
The NHS recommends that adults drink no more than 14 units each week – that’s 14 single shots of spirit, six pints of beer or a bottle and a half of wine
Binge drinking is equally risky. For women, this is classed as six units in one sitting – about two large glasses of wine.
Regular weekend binge drinkers who consume eight medium glasses over two days have a 24 per cent greater risk of breast cancer.
Even those who stick to four glasses per weekend are 12 per cent more likely to develop the disease.
Dr Liz O’Riordan, a breast cancer specialist who has had the disease three times herself, said: ‘I knew the risks, and I ignored them. There is no safe level of alcohol consumption and people need to know that.
‘The two biggest risk factors of getting breast cancer are your age and being a woman, neither of which we can do anything about – but you can control how much you drink.
‘So if you want to reduce your risk of breast cancer, you need to cut down.
‘The impact of alcohol increases as you age, and it is never too late to change habits and reduce your risk.’
According to the latest NHS figures, 81 per cent of adults said they had consumed alcohol in the past year – with men more likely than women to have done so (84 per cent compared to 78 per cent).
Breast cancer is the UK’s most common cancer, with almost 56,000 cases diagnosed per year
Symptoms of breast cancer to look out for include lumps and swellings, dimpling of the skin, changes in colour, discharge and a rash or crusting around the nipple
Currently the NHS recommends a limit of 14 units per week – equivalent to six medium glasses of wine or six pints of beer.
Men are more likely to drink more than this (32 per cent) than women (15 per cent).
However, 55 per cent of men and 42 per cent of women drank alcohol at least once a week, according to the Health Survey for England data.
Experts say current ‘safe drinking’ guidance is outdated and does not acknowledge the known link between alcohol and seven types of cancer.
‘The national guidelines need to be lowered, as is being done in other countries, as there are no safe levels of alcohol,’ says Dr O’Riordan.
‘The link to cancer needs to be acknowledged. If you want to have one glass of something you enjoy every so often, or six glasses a year, then that would be fine, but do not make it a habit.’
Checking your breasts should be part of your monthly routine so that you notice any unusual changes. Simply rub and feel the breast from top to bottom, and feel in semi-circles and in a circular motion around your breast tissue to check for any abnormalities
According to Professor Jayant Vaidya, an oncologist at University College London as part of their Tobacco & Alcohol Research, the relationship between alcohol and breast cancer is ‘dose dependent.’
He says: ‘When you have a glass of wine you are paying the price for the joy you are experiencing, with an increased risk of breast cancer.
‘It is dose dependent so for every drink you have you are increasing your risk. You need to balance the risk and should reserve alcohol for special occasions only.’
However some experts argue that advising women to completely cut out or drastically limit intake may be too drastic, and even counterproductive.
‘There needs to be a common sense approach,’ says Professor Hendrik Tobias Arkenau, an oncologist at University College London.
‘Of course there is a risk when you consume alcohol but one drink a week will not increase your risk considerably.
‘If we advise everyone to go teetotal it does not acknowledge the cultural role alcohol has and will undoubtedly affect people’s quality of life.’
Alcohol increases breast cancer risk in two main ways – it is broken down in the body into acetaldehyde, a carcinogen that can damage DNA, including in breast tissue.
It also raises levels of oestrogen, a hormone known to fuel the development and growth of many breast cancers.
Dr O’Riordan also warns that alcohol can increase breast density, a known risk factor for cancer.
Dense breasts also makes tumours harder to spot with current screening methods.
Cancer Research UK estimates that eight per cent of breast cancer cases diagnosed annually in the UK are directly linked to alcohol consumption.
Despite this, one in four adults in England drink above the NHS recommended limit.
The Institute of Alcohol Studies estimates that the average British woman consumes around nine units a week, putting most in the range of a 9 to 15 per cent increased risk.
Survival rates for breast cancer have doubled in the last 50 years, with three-quarters of women now surviving at least 10 years post-diagnosis, thanks to better screening and increased awareness.
Women are encouraged to regularly check their breasts for signs of cancer, including lumps or swellings; changes in size, shape or colour; nipple discharge; a rash or crusting around the nipple; skin dimpling or persistent pain.
Anyone concerned is urged to contact their GP, and those worried about their alcohol consumption can also seek support via their doctor.
Did boozing in my 20s cause my breast cancer?
Former breast cancer surgeon Dr Liz O’Riordan says: ‘The national guidelines need to be lowered, as is being done in other countries, as there are no safe levels of alcohol’
Dr Liz O’Riordan has had breast cancer three times, and suspects it may have been caused by heavy boozing when she was younger.
‘I knew the risks but I ignored them. I drank like a fish at medical school – we were told that alcohol raised cancer risk but it didn’t sink in,’ says Dr O’Riordan. ‘I have often wondered whether my own heavy drinking as a junior doctor might have played a part in my diagnosis.’
However, the former breast surgeon, who wrote The Cancer Roadmap, published in January, warns that you should not feel guilty about past drinking habits.
She adds: ‘It is never too late to change your habits, and the risk compounds as you age so you need to be aware of it.
‘I’m not teetotal but I barely drink and I’m in the best shape of my life, but it has been a slog to get here.’
