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Updated at 11.30am
MIDDLE-AGED PEOPLE who are underweight are a third more likely to develop dementia than people of similar age with a healthy body mass index (BMI), according to new research.
A study published in the Lancet Diabetes and Endocrinology journal found that middle-aged people with a BMI less than 20 kg/m2* are more at risk of getting the condition.
The findings, which come from the largest-ever study to examine the statistical association between BMI and dementia risk, also show that middle-aged obese people (BMI greater than 30 kg/m2) are nearly 30% less likely to develop dementia than people of a healthy weight.
This contradicts findings from previous research which suggested that obesity leads to an increased risk of dementia.
Researchers based at the London School of Hygiene & Tropical Medicine and OXON Epidemiology analysed data from the Clinical Practice Research Datalink (CPRD), a large database of patient information recorded during routine general practice over nearly 20 years – representing around 9% of the UK’s population.
The researchers analysed the medical records of nearly two million (1,958,191) people with an average age of 55 years at the start of the study period, and an average BMI of 26.5 kg/m2, just within the range usually classed as overweight.
During an average of nine years follow-up, 45,507 people were diagnosed with dementia.
People who were underweight in middle-age were a third (34%) more likely to be diagnosed with dementia than those of a healthy weight, and this increased risk of dementia persisted even 15 years after being underweight was recorded.
As participants’ BMI at middle-age increased, the risk of dementia reduced, with very obese people (BMI greater than 40 kg/m2 ) 29% less likely to get dementia than people in the normal weight range.
An increase in BMI was associated with a substantial steadily decreasing risk of dementia for BMI of up to 25 kg/m² (classed as a healthy weight). Above a BMI of 25 kg/m² (classed as overweight or obese), dementia risk decreased more gradually, and this trend continued up to a BMI of 35 kg/m² or higher.
The association between BMI and dementia risk wasn’t affected by the decade in which the participants were born, nor by their age at diagnosis. Adjusting for confounding factors known to increase the risk of dementia, such as alcohol use or smoking, made little difference to the results.
More research needed
Study author Professor Stuart Pocock from the London School of Hygiene & Tropical Medicine said the results “suggest that doctors, public health scientists, and policy makers need to re-think how to best identify who is at high risk of dementia”.
We also need to pay attention to the causes and public health consequences of the link between underweight and increased dementia risk which our research has established.However, our results also open up an intriguing new avenue in the search for protective factors for dementia – if we can understand why people with a high BMI have a reduced risk of dementia, it’s possible that further down the line, researchers might be able to use these insights to develop new treatments for dementia.
Dr Nawab Qizilbash from OXON Epidemiology said the reasons why a high BMI might be associated with a reduced risk of dementia “aren’t clear, and further work is needed to understand why this might be the case”.
Responding to the research, Professor Deborah Gustafson from SUNY Downstate Medical Center in New York noted that some studies “report a positive association between high mid-life BMI and dementia, whereas others do not”.
“To understand the association between BMI and late-onset dementia should sober us as to the complexity of identifying risk and protective factors for dementia. The report by Qizilbash and colleagues is not the final word on this controversial topic,” Gustafson added.
*Although a BMI less than 18.5 kg/m2 is usually classed as underweight, a slightly higher threshold (20 kg/m2) was used in this study to enable comparison with earlier studies.
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It’s a shame that Russia just so happens to have a significant military presence in Syria. After losing out on those lucrative contracts in Lybia thanks to NATO, it’s no wonder they’re stopping the UN from getting involved. Sad day when people put money and influence ahead of innocent lives.
fyi i shouted nothing…caps in text refers shouting..i dont use caps
I don’t know what you’re talking about but I will say your comments are generally painful to read with no spaces, no capitals, bad grammar and very poor punctuation. I still read them though
Reeply meant for another comment. I rechecked my comments, plenty spaces and good spelling but sure I’m not perfect
this woman speaks the truth..the world must act now!
Try this if you want to understand a little about what is really going on in Syria http://www.atimes.com/atimes/Middle_East/NB04Ak01.html#Scene_1
you sir accused me of “getting off on seeing muslims slaughtered” that is bilious vile crap which i.find highly insulting and abusive..btw im.no propagandist but sure why do i bother!
What’s been most striking about the Syrian situation as an Irish observer is the utter silence from the Irish govt, the Irish anti war groups , Sinn Fein etc on the subject. Not even a single statement of solidarity for the people being mowed down day after day by their own government’s bullets.
Where are the flotillas, the champagne socialists , the celebrity endorsements that we saw take aim at Israel over the Gaza situation? The deputy director of the red cross stated recently that there is no humanitarian crisis in gaza , but surely there is one in Syria? The government there are shelling residential housing estates every day, and yet we’ve heard nothing, NOTHING from messrs Boyd Barrett and his ilk on the topic.
I suspect this is because the Irish left ( I include Sinn Fein and Labour in this) know how Syria would deal with them ( the business end of a belt fed machine gun) and are therefore selective in their assertions of do-gooderness. The other aspect of it is that they are, fundamentally, Anti-west, Anti-American, Anti-Israeli, and they only dip their toes In when whitey or his friends does something they don’t agree with.
For everyone else (libyans, Egyptians, Syrians, Saudis etc) they’re not too bothered when Arabs butcher other Arabs because the Irish left sees them through an insidiously but equally racist filter – as victims of their history or their culture , who cannot be held to account or treated like adults.
Nice rant there Eric but your facts let you down. That Red Cross myth has already been dealt with on the Journal at the time of the Gaza flotilla and shown to be exactly what it is, a myth, urban legend, call it what you will.
Irish Government silent…http://www.merrionstreet.ie/index.php/2011/12/tanaiste-condemns-ongoing-violence-in-syria/ “Tánaiste Condemns Ongoing Violence in Syria”. Richard Boyd Barrett in a Dail debate ” The Minister is totally wrong there. I am 100% on the side of the people fighting for democracy against the brutal Assad dictatorship” The Irish War Movement has plenty to say on their website about Syria and the ongoing conflict there.
Just because you might have missed their condemnations of the regime and support for the rebels doesn’t mean that they have kept silent.
Eric you could at least do a little bit of research before spreading such lies and accusations.
for the record..i have the highest regard for Islam and pass this on ti my children whise friends are jewish muslim.and christian. i hate to see innocent life squandered..there are always two sides to every conflict and as has been shown in my country compromise is necessary. i have relationscand friends who served in lebanon who.saw at first hand the war crimes that were shabra and chatila…i condemned the butcher of those crimes ariel.sharon when.he undermined ehud baraks peace negotiations with yasser arafat by marching on.thevTemple Mount aka Dome of the Rock. i disagree with the proliferation.of settlements. but those who insult and harranue me for my.views conveniently ignore the bulldozing of illegal settlements by direction.of netanyahu..the prosecution.of ultra orthodox jews who have terrorised girls for “immodest clothing” and who ignore the history of Israel..the facts
Seem if Colm doesn’t agree with you’re comments they get deleted even if the majority agree with them ?
Syrias biggest failure is failing to protect their citizens from the NATO murder machine. Anyone who can’t see the real story in Syria, should be ashamed at their stupidity. Wake up. We live in a world where Israel can blame Iran for bombing their embassies immediately after with no due process. How crazy is that. The demonisation of Syria is no different. We are spinning headlong towards another world war. Guess too many people with too much power are too thick.
Get a room….zzzzz
I’m sorry but they played the rape card with Libya and only after the war had been perpetrated did those of us who made the effort learn that it was all lies. Humanitarianism is being tarnished and subverted by people who are pursuing an Israelist agenda in the Middle East.
Negotiations and a cease fire were offered by Assad months ago and Western leaders had the arrogance to reject them on behalf of the people in Syria whose lives were in danger from the fighting. Russia seems to be the only government working to achieve peace with no ulterior motives. And so they are cast as the villain the American/Euro version of events.
ceasefires were offered by assad but never implemented never respected by his forces. wheres the link.that proves western givts rejected ceasefires..how could they they are not a party to the conflict.
There is no coincidence that as soon as the war in Libya ends Syria blows up .The NATO/Arab league cabal have been shipping arms and insurgents into Syria for months.Asad is not a nice guy but he has the majority of the people behind him .How about reporting on the Bahraini government using Saudi troops to massacre Shi’ite protesters ,or the US backed Yemeni governments atrocities No lets jump on fantasy rapes ,maybe you could try babies murded in incubators it worked against the Iraqis !
Obama and Hillary Clinton publicly dismissed Assad’s offers to negotiate and implement reforms. When the leaders of the global superpower make such statements they have weight enough to effect the decisions made by the Syrian opposition. Why would they even bother negotiating a peaceful solution when Obama and his Secretary of State are dismissing the very idea of it? The West has led the rebels to believe that they have a NATO-insured uprising and therefore have every reason to go for broke and hold out for a complete uncompromising victory.
You and I can argue about which side was doing the attacking but that would be futile. Assad said he implemented a cease-fire but the rebels kept on fighting. But the two people we have proof did not respect them are Obama and Clinton – their remarks are part of the public record.
sir I am not a racist..withdraw that acvusation please. iv never supported use of white phosphorous on combatants or civilians! and Israel is a fully functioning democracy. fyi ive reported your scurrilous comments as they are clearly in.breach of the policy
journal…these insulting rants are getting tiresome..this post above has.made scurrilous accusatiins about me
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