Image caption Ad hoc drinking may mean we do not actually know how much we are consuming 
 
 The amount of alcohol consumed in England could be much higher than previously thought, a study suggests. 
 
 University College London researchers compared alcohol sales figures with surveys of what people said they drank. 
 
 They found there was a significant shortfall with almost half of the alcohol sold unaccounted for in the consumption figures given by drinkers. 
 
 This suggests as many as three-quarters of people may be drinking above the recommended daily alcohol limit. 
 
 The researchers reached their estimates by factoring in the "missing" alcohol - and found excess drinking was far more than suggested by official figures, they told European Journal of Public Health. 
 
 Experts said much alcohol use went unreported, partly because drinkers did not admit or keep track of how much they consumed. 
 
 'Health implications' 
 
 The study found that 19% more men than previously thought were regularly exceeding their recommend daily limit - and 26% more women. 
 
 Total consumption across the week was also higher than officially thought - with 15% more men, and 11% more women drinking above the weekly guidelines. 
 
 The current recommendation set by the UK Chief Medical Officers is not to regularly exceed four units per day for men and three units a day for women; the Royal College of Physicians recommends weekly alcohol limits of 21 units for men and 14 units for women - although these are currently under review. 
 
 A unit of alcohol is roughly equivalent to half a pint of ordinary strength beer, or nearly one small (125ml) glass of wine. 
 
 Sadie Boniface, lead author of the study at University College, said: "Currently we don't know who consumes almost half of all alcohol in England. This study was conducted to show what alcohol consumption would look like when all of what is sold is accounted for, if everyone under-reported equally. 
 
 "The results are putative, but they show that this gap between what is seen in the surveys and sales potentially has enormous implications for public health in England." 
 
 The team used alcohol sales data from Revenue and Customs and compared it with two self-reporting alcohol consumption surveys conducted in 2008 - the General Lifestyle Survey (GLF) which analysed average weekly alcohol consumption in 12,490 adults, and the Health Survey for England (HSE) which looked at consumption on the heaviest drinking day in the previous week among 9,608 adults. 
 
 Counting units 
 
 The researchers say they will now look at the characteristics of those that are under-reporting the number of drinks they have had, and why. 
 
 They suggest it may be down to drinking patterns and habits - those that are mixing drinks, and drinking at different venues, may be more likely to under-report. 
 
 Media playback is unsupported on your device Media caption Alcohol Concern's Eric Appleby: "Particularly when we drink at home, we pour much larger measures" 
 
 The charity Alcohol Concern suggests irregular and chaotic drinking behaviour may play a part: "When we're totting up our drinks total we don't always count some occasions as proper drinking. 
 
 "We may underestimate drink sizes and their alcoholic content, and not count holidays and special occasions like weddings, birthdays and Christmas when we often drink a great deal more than usual." 
 
 The researchers suggest that government drinking guidelines need to reflect actual consumption instead of reported drinking - especially when ascertaining what levels are associated with harm. 
 
 The Department of Health says this will be taken into consideration in their alcohol consumption review. 
 
 It said: "We already know people underestimate what they drink and many drink too much. That's why we work to help people make healthier decisions, including the recent Change For Life campaign to help them track consumption and understand the impact on their health. 
 
 "We're also tackling excessive drinking through our proposed minimum unit price at 45p per unit, tougher licensing laws, more GP risk assessments, better access to specialist nurses and more specialised treatment." 
 
 Diane Abbott MP, Labour's shadow public health minister, said: "This has got to be a wake-up call for the government and the country, because after more than two years of bitter internal rows, the government has got cold feet about its only proposed alcohol harm policy. 
 
 "More needs to be done to tackle problem drinking, which costs the country £21bn." ||||| Moderate alcohol consumption can impair cognitive function, says study, countering suggestions that low levels of drinking can help protect the brain 
 
 Drinking even moderate amounts of alcohol can damage the brain and impair cognitive function over time, researchers have claimed. 
 
 While heavy drinking has previously been linked to memory problems and dementia, previous studies have suggested low levels of drinking could help protect the brain. But the new study pushes back against the notion of such benefits. 
 
 “We knew that drinking heavily for long periods of time was bad for brain health, but we didn’t know at these levels,” said Anya Topiwala, a clinical lecturer in old age psychiatry at the University of Oxford and co-author of the research. 
 
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 Writing in the British Medical Journal, researchers from the University of Oxford and University College London, describe how they followed the alcohol intake and cognitive performance of 550 men and women over 30 years from 1985. At the end of the study the team took MRI scans of the participants’ brains. 
 
 None of the participants were deemed to have an alcohol dependence, but levels of drinking varied. After excluding 23 participants due to gaps in data or other issues, the team looked at participants’ alcohol intake as well as their performance on various cognitive tasks, as measured at six points over the 30 year period. 
 
 The team also looked at the structure of the participants’ brains, as shown by the MRI scan, including the structure of the white matter and the state of the hippocampus – a seahorse-shaped area of the brain associated with memory. 
 
 After taking into account a host of other factors including age, sex, social activity and education, the team found that those who reported higher levels of drinking were more often found to have a shrunken hippocampus, with the effect greater for the right side of the brain. 
 
 While 35% of those who didn’t drink were found to have shrinkage on the right side of the hippocampus, the figure was 65% for those who drank on average between 14 and 21 units a week, and 77% for those who drank 30 or more units a week. 
 
 The structure of white matter was also linked to how much individuals drank. “The big fibre tracts in the brain are cabled like electrical wire and the insulation, if you like, on those wires was of a poorer quality in people who were drinking more,” said Topiwala. 
 
 
 
 In addition, those who drank more were found to fare worse on a test of lexical fluency. “[That] is where you ask somebody to name as many words as they can within a minute beginning with a certain letter,” said Topiwala. People who drank between seven and 14 units a week were found to have 14% greater reduction in their performance on the task over 30 years, compared to those who drank just one or fewer units a week. 
 
 By contrast, no effects were found for other tasks such as word recall or those in which participants were asked to come up with words in a particular category, such as ‘animals.’ 
 
 Expert reaction to the the study was mixed. While Elizabeth Coulthard, consultant senior lecturer in dementia neurology at the University of Bristol, described the research as robust, she cautioned that as the study was observational, it does not prove that alcohol was causing the damage to the brain. 
 
 Daily glass of wine increases a woman's cancer risk, finds study Read more 
 
 In addition, the majority of the study’s participants were men, while reports of alcohol consumption are often inaccurate with people underestimating how much they drink – an effect that could have exaggerated the apparent impact of moderate amounts of alcohol. 
 
 Dr Doug Brown, director of research and development at Alzheimer’s Society said that the new research did not imply that individuals should necessarily turn teetotal, instead stressing that it was important to stick to recommended guidelines. 
 
 
 
 In 2016, the Department of Health introduced new alcohol guidelines in the UK, recommending that both men and women drink no more than 14 units of alcohol each week – the equivalent of about six pints of beer or seven 175ml glasses of wine. 
 
 “Although this research gives useful insight into the long-term effects that drinking alcohol may have on the brain, it does not show that moderate alcohol intake causes cognitive decline. However, the findings do contradict a common belief that a glass of red wine or champagne a day can protect against damage to the brain,” said Brown. ||||| (CNN) Drinking in moderation can help our health , some research has showed. Many doctors recommend a glass of wine or beer a night as part of diet plans such as the Mediterranean diet and the DASH diet , which have been proven to keep your heart and brain healthy. However, a new study suggests that even moderate drinking may not be great for your brain. 
 
 As part of the study, which was published Wednesday in the BMJ , researchers looked at people's weekly alcohol intake from the Whitehall II study , which tracks disease and social behaviors in a group of British civil servants for 30 years. University of Oxford and University College London scientists studied how participants fared with regular brain function tests and an MRI. 
 
 What they noted was that the people who drank the most had the highest risk of hippocampal atrophy , a form of brain damage that can impact spatial navigation and can be associated with memory-loss conditions like Alzheimer's and dementia. The heavier drinkers saw a faster decline in language skills and had poorer white matter integrity , which is crucial to processing thoughts quickly. 
 
 If you're starting to worry and are afraid to drown your sorrows, note that there are many caveats, and more research needs to be done. Some experts suggest you shouldn't change your drinking behavior based on this one study, but the results of these brain scans and memory tests for moderate and lighter drinkers were not what researchers expected. 
 
 "We were surprised that the light to moderate drinkers didn't seem to have that protective effect," said study co-author Dr. Anya Topiwala , a clinical lecturer in the Department of Psychiatry at the University of Oxford. "These are people who are drinking at levels that many consider social drinkers, so they are not consuming a lot." 
 
 Even the heaviest of the drinkers aren't big nightly bingers. The "drank the most" group in this study consumed about 30 units of alcohol a week, with a unit considered to be 10 milliliters or 8 grams of pure alcohol. A medium glass of wine has about two units of alcohol, and so does a pint of some beers, depending on the alcohol content. 
 
 If you do the boozy math, the study's heaviest drinkers had a little more than two medium glasses of wine or two beers every night of the week. 
 
 The moderate group was drinking about 14 to 21 units of alcohol per week, or about a medium glass of wine each night, plus a little extra on the weekends. 
 
 Researchers discovered that the moderate group was three times more likely to have hippocampal atrophy compared with people who didn't drink at all. However, in the heavy and moderate drinkers, there is no evidence to show how clinically significant this change is, and there is no evidence linking this loss to any negative general cognitive effects, even the ones for which the participants were tested. 
 
 With the light drinkers, those who had a small glass of wine a night or up to seven units per week, researchers didn't see a significant difference compared with the abstainers, but they didn't see any protective qualities, either. 
 
 The abstainers may be one subject that needs further development, according to Eric Rimm , a professor of medicine and director for the program in cardiovascular epidemiology at Harvard T.H. Chan School of Public Health. 
 
 Rimm, who was not involved in the new study, has researched the impact of alcohol for years. He said that although the study has an interesting hypothesis, the abstainer group (22 men and 15 women) is tiny and may be throwing off the results. 
 
 If you are a moderate drinker, he said, you don't have to give up the booze based solely on this report. 
 
 "There are so many other lifestyle factors that are not taken into account in this study, like nutrition. Eating whole grains and fruits and vegetables have been linked with slower cognitive decline," Rimm said. Attributing mental decline to alcohol is too limited, he said. 
 
 Tom Dening, a professor of dementia research and Director of the Centre for Old Age and Dementia at the University of Nottingham, called the study "most impressive" and suggests it may be a good reminder that "perhaps we should all drink a bit less," but he also questioned its results. People typically are not honest about how much they really drink, he noted. 
 
 "People tend to underestimate their actual consumption, partly to appear more respectable," Dening said. "If actual consumption was under-reported, then the apparent adverse effects of modest amounts of alcohol could have been magnified." 
 
 Earlier studies have also shown that people tend to drink less as they age, said Carl Heneghan , director of the Centre for Evidence-Based Medicine at the University of Oxford, who was not involved in the new research. 
 
 "These type of studies also cannot account for all the (factors), and therefore they cannot, and should not, conclude causation," Heneghan said. "Using all the available evidence provides a much more balanced approach for the public on deciding how much to drink." 
 
 Rimm wondered whether there were so few abstainers in the study because, after 30 years, they hadn't lived as long as the others. 
 
 When it comes to the brain, this is not the first research to question whether drinking even moderate amounts had an impact, though results have been mixed. One 2008 study found that unlike with the heart, for which alcohol has protective qualities, the more people drank, the smaller their total brain volume, meaning their brains aged faster. 
 
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 "An observational study cannot truly prove that alcohol causes dementia, but the findings are in keeping with my clinical experience," said Dr. Elizabeth Coulthard , a consultant senior lecturer in Dementia Neurology at the University of Bristol who was not involved in the new research. "Hopefully this research will contribute to a greater understanding of true safe limits for alcohol consumption that ensure protection from future dementia. Until we have further studies, the good news is that low alcohol intake was not associated with brain or memory decline in this sample." 
 
 Topiwala said she and her co-authors want to try to replicate the results, particularly with a more diverse population. Most in this study were men with similar backgrounds, with generally higher IQs than the population as a whole, all factors that can affect the results. 
 
 "We think, though, this study asks some really important questions in an area that does have a knowledge gap," Topiwala said.
– People in Britain are drinking a lot more alcohol than they care to admit, say researchers at the London's University College. They compared the amounts that people say they drink with actual alcohol sales and found that about 40% of the booze sold is mysteriously unaccounted for, reports the Telegraph. The study's authors estimate that 44% of men and 31% of women were exceeding government guidelines for weekly consumption, notable jumps in both categories. “Particularly at home, people underestimate how much they drink," says one of the authors. British government guidelines say men should drink no more than four units of alcohol a day, which equates to two pints of beer; for women, it's three units per day, the equivalent of three small glasses of wine. The weekly limits are 21 units for men and 14 for women, reports the BBC.