Heavy drinking has long been linked to a greater risk of Alzheimer’s disease – but scientists now believe people whose faces flush after drinking alcohol may be especially vulnerable.

A new study from the University of Florida examined how a toxic byproduct of alcohol may reshape the brain at a cellular level.

Researchers focused on acetaldehyde, a harmful compound produced when the body breaks down alcohol, and a gene variant linked to the so-called alcohol flush reaction.

The gene, ALDH2, provides instructions for making an enzyme that helps convert acetaldehyde into acetate, a less toxic substance that can be more easily processed and cleared by the body.

But some people carry a faulty version of the gene, known as ALDH2*2, which means they clear acetaldehyde less efficiently. 

This can cause acetaldehyde to build up after drinking, triggering symptoms such as facial flushing, nausea, headaches and a racing heart.

In the study, researchers used mice genetically engineered to carry the ALDH2*2 variant to examine how acetaldehyde toxicity from chronic heavy alcohol use may influence brain inflammation, metabolic dysfunction and tau pathology – a hallmark of Alzheimer’s disease.

‘People carrying this variant struggle to clear acetaldehyde efficiently, allowing this toxic compound to linger like an unwelcome guest and fuel inflammation and oxidative stress throughout the body, including the brain,’ said Nagalakshmi Balasubramanian, the study’s lead author.

Just a couple of glasses a wine a night could increase your risk of developing Alzheimer’s, especially if your prone to flushing, new research has suggested

Everyone experiences dementia differently. Use this checklist to help you make a note of your symptoms before you talk to your GP.

‘While carrying this variant does not mean someone is destined to develop Alzheimer’s disease, it may stack the deck toward accelerated ageing and neurodegeneration, especially in people with chronic heavy alcohol exposure.’

She added that heavy drinking – generally defined as more than eight drinks per week for women or 15 for men over long periods – may leave a lasting imprint on brain health.

The research – which was presented at the annual meeting of the Research Society on Alcohol – also aimed to find out whether boosting ALDH2 activity could help the brain fight back against alcohol-induced damage. 

They concluded that identifying these molecular ‘red flags’ and genetic variations early may ‘pave the way for earlier detection and more targeted human therapies before irreversible brain damage takes hold.

‘Research suggests that chronic alcohol use can fast-track biological aging in the brain and ‘fan the flames’ of pathways linked to Alzheimer’s,’ Balasubramanian added. 

‘Alcohol can trigger inflammation, oxidative stress and metabolic dysfunction while also contributing to depression, anxiety and social withdrawal, changes that are often early warning signs of the disease.

‘In many cases, the writing may be on the wall long before memory loss appears. 

‘When it comes to protecting brain health, knowledge truly is power.’

This study isn’t the first one to suggest that cutting down on alcohol consumption could play a significant role in preventing the disease. 

Recent research found drinking any amount of alcohol may increase the risk of developing dementia. 

The study, led by experts at the Universities of Oxford, Cambridge and Yale looked at data from 559,559 people and found people who did not drink at all , and those who drank heavily had higher dementia risk than light drinkers. 

However, researchers said this was likely to be the result of people with early symptoms cutting back on or giving up alcohol entirely.  

There are an estimated one million people in the UK living with dementia – and by 2040 that figure is expected to climb to 1.4 million. 

But while the search for a cure continues, there is mounting evidence that prevention may be the best form of defence for now.

A major consensus earlier this year by world-leading experts, building on The Lancet Commission on Dementia concluded that almost half of all cases globally could be prevented, or at least delayed for several years, if action was taken to address 14 risk factors – ranging from smoking and excess alcohol consumption, to loneliness and a sedentary lifestyle – that are driving up rates of illness.

NHS guidelines state adults shouldn’t drink more than 14 units a week, the equivalent of one medium glass of wine a night. 

He’s not the only male politician to be affected by them – nor, potentially, the only prime minister (David Cameron and Boris Johnson are fellow sufferers).

For clearly on view during Andy Burnham‘s victory parade for his landslide win in the Makerfield by-election last week was evidence of the curse that affects an estimated 12 million males in the UK – man boobs, or ‘moobs’.

The ex-mayor of Manchester had ditched his much-loved black T-shirt look for a white polo shirt which was, as the Mail’s parliamentary sketch writer Quentin Letts observed, ‘untucked at the waist – hoping to disguise his man boobs’.

But back to his black T-shirt on Monday, when he travelled to London to be sworn in as an MP, there was no hiding them.

A keen runner, 56-year-old Burnham appears slim-ish, with no major weight issues, yet the Labour ‘Messiah’ seems to be struggling with possible signs of gynaecomastia – or enlarged male breasts.

So what are the causes of this extremely common complaint – can it be a warning sign of a more serious but hidden health issue? And what, if anything, can you do to minimise them – or at least their appearance?

There are in fact two types of moobs – so-called ‘true’ gynaecomastia, which is most commonly due to a long-term hormonal imbalance, either from adolescence onwards or later in life (over 55) when a man’s hormone levels are again disrupted, this time by the ageing process.

Then there is ‘pseudogynaecomastia’ – or man boobs that form in men who are overweight, rather than as a result of an underlying hormonal or medicine-related problem (but more on this later).

Andy Burnham with his wife Marie-France van Heel after his landslide victory in the Makerfield by-election

‘True’ gynaecomastia – abnormal breast growth – is common during adolescence, when puberty lights a rocket under young males’ hormones. Teenage boys produce more oestrogen during puberty as it’s vital for the adolescent growth spurt, during which bones harden and grow. This ‘female’ hormone is also essential for brain development and is even crucial for the male body to be able to make sperm.

But it also promotes the growth of the glandular tissue that makes up much of the breast; hence, a hormone imbalance where oestrogen is too high and testosterone too low, which temporarily sends breast tissue growth into overdrive.

Most teenage boys grow out of this – and their breast size returns to normal as they mature into adulthood – but for an estimated 30 per cent, moobs become a permanent feature, often affecting them psychologically as well as physically. Some research suggests more than 90 per cent of those affected suffer depression, anxiety and self-esteem issues as a result.

‘It can have a huge impact on men’s wellbeing,’ says Ash Mosahebi, a professor of plastic surgery at the Royal Free Hospital in London.

‘Many are deeply embarrassed by their appearance. They just want to be able to go to the beach and look normal.’

In middle age and older, naturally falling testosterone levels trigger the same process. In fact, this drop-off in levels of the ‘male’ hormone starts at around 30 and, in most men, continues a steady decline of around 1 per cent a year.

This drop can be exacerbated by poor diet and lifestyle, which means oestrogen comes to dominate.

Treatments include giving men tamoxifen – the well-known breast cancer drug which works by suppressing oestrogen levels – or injections to boost their testosterone, if blood tests show it is lower than it should be. At any age, surgery is also an option. It takes a couple of hours and involves making a small incision around the edge of the nipple to extract the excess tissue. (You can get it on the NHS but only under strict guidelines, which dictate patients must be in pain – due to inflammation in the breast tissue – and been suffering for at least a year). Private surgery costs between £3,000 and £8,000.

The newly elected MP at Manchester Piccadilly station earlier this week as he travelled down to London

Other causes of gynaecomastia in men of any age include certain prescription drugs which can have an ‘oestrogenic’ effect on the male body.

These include spironolactone, a pill widely used on the NHS to treat high blood pressure, heart failure and oedema (fluid retention). The drug suppresses testosterone output and increases oestrogen levels.

Even the commonly prescribed heartburn drug omeprazole (the NHS in England dishes out 35million prescriptions a year) has been linked with an increased risk – again through the effect it has on oestrogen levels.

This can be reversed if the patient is moved off the drug, though the longer you ignore this, the less likely it will improve, as the extra glandular tissue will have formed.

Meanwhile, some studies suggest cannabis use can also heighten the dangers through a similar oestrogenic effect – though a major analysis by scientists in China, published in Annals of Paediatric Endocrinology and Metabolism in January last year, found no evidence of a link.

Gym bunnies who abuse anabolic steroids are also at a very high risk of gynaecomastia, as any excess testosterone they consume simply gets turned into oestrogen by an enzyme that stimulates breast tissue growth.

Some studies suggest at least half of those who use steroids to bulk up develop man boobs. Many end up needing surgery even after quitting the drugs.

Then there’s ‘pseudogynaecomastia’ – or man boobs that form in men of any age who are overweight, rather than as a result of an underlying hormonal or medicine-related problem.

In these men, the tissue enlarging their breasts is almost entirely fat – rather than anything more structural (although excess body fat can lead to more testosterone being converted to oestrogen so some of the enlarged tissue will be glandular).

Some experts believe the rise in demand in recent years from young men for treatments to banish their moobs is linked to Britain’s increase in childhood obesity (more than a fifth of 11-year-old boys and girls are now classed as obese) which then gets carried over into adolescence and young adulthood.

Anecdotal evidence suggests this is on the increase, with private cosmetic surgery clinics reporting a steady increase in recent years in men seeking treatment to shrink their moobs.

‘Most cases I see are due to men being fat,’ says Professor Mosahebi. ‘If you have a large tummy, you’re very likely to also have large breasts.’

Weight loss is the most obvious solution – as the pounds fall off, fat cells in the breast area shrink and the moobs reduce in size.

Exercises such as a bench press (where you lie with your back on the floor and slowly raise and lower dumbbells above your chest 12 times – then repeat) can tighten up moobs and give a firmer appearance.

But some men who find they cannot shift stubborn fat deposits, despite exercising and eating healthily, or who, like Andy, aren’t fat can opt for privately provided liposuction. Here doctors use lasers, radio waves or ultrasound to destroy fat cells before sucking them out with a device.

However, the procedure costs around £5,000.

In most cases, says Professor Mosahebi, moobs are nothing to worry about, other than how they make men feel about themselves.

Yet there are some exceptions. In extremely rare cases, man boobs can be a sign of breast cancer – particularly if the enlargement happens suddenly and on one side only.

‘If so, and it’s recent, it would need to be investigated,’ he says.

‘But if both sides are affected it’s almost certainly not cancer.’

Meanwhile, some research suggests ‘true’ gynaecomastia – that linked to surplus glandular tissue rather than fat – may be linked with a poorer long-term health outlook.

A 2024 study by experts at the University of Copenhagen, published in BMJ Open, tracked more than 23,000 men diagnosed with gynaecomastia due to enlarged breast tissue and found they were 37 per cent more likely to suffer a premature death (before the age of 75) – from any cause – than men without the condition.

Researchers said it’s not clear why this was but one explanation might be that the gynaecomastia was nothing more than a marker – in other words, they already had a chronic or serious illness and the potent drugs they were taking to treat it may have caused them to have enlarged breast tissue.