Exercise in middle-age 'stops your brain shrinking'

NHS Choices - Behind the Headlines - Thu, 11/02/2016 - 13:30

"A new study has suggested that exercising in your 40s could stop the brain shrinking," The Daily Telegraph reports.

A study found people with good fitness levels in their 40s had larger brains than their unfit peers when measured 20 years later. The concern is that people with smaller brains may be more likely to develop dementia.

The study, part of a big ongoing research project in the US (the landmark Framingham Heart Study) measured people's exercise capacity and heart and blood pressure reactions to exercise during a treadmill test, at an average age of 40.

The same people were assessed about 20 years later, with a repeat exercise test and an MRI scan to determine brain volume.

People with 20% less fitness compared to the average, had smaller brains by the equivalent of one additional year of ageing. A similar effect was seen for higher blood pressure or heart rate in response to exercise.

However, we don't know the importance of the brain size differences measured and as this was only done once, it is not clear whether the size had actually changed.

So we cannot be sure fitness levels directly caused the differences in brain size. But the research does add to the growing evidence that physical fitness and better mental capacity in older age go hand-in-hand. 

What is good for the heart tends to also be good for the brain. Read more about how exercise may reduce your dementia risk.


Where did the story come from?

The study was carried out by researchers from Boston University School of Medicine, Framingham Heart Study, Harvard Medical School, Broad Institute of MIT and Harvard and the University of California. It was funded by the National Institutes for Health and the American Heart Association. 

The study was published in the peer-reviewed journal Neurology.

Reports in the UK media overstated the certainty of the study. The Daily Mail's headline: "Being a couch potato shrinks the brain," makes the results sound more definite than they are. The report says that "failing to exercise" was the cause of smaller brains. 

The Daily Telegraph says the study "revealed … exercising when aged between 40 and 50 could help prevent the brain shrinking". However, the study did not look at whether people exercised, how much they exercised or at what age. It only included information about their fitness levels, blood pressure and heart rate.


What kind of research was this?

This is a prospective cohort study, which tracks people over a long period of time and compares information taken at different time points. It's a good way to look for links between factors – in this case between fitness and later brain size. However, it cannot prove that one thing causes another.


What did the research involve?

Researchers took a large group of people, average age 40, and tested their fitness levels using a treadmill. They recalled them 20 years later to repeat a fitness test and have an MRI brain scan and cognitive tests. They looked for links between fitness at the first test and brain size and cognitive skills 20 years later.

The fitness tests involved people exercising on a treadmill until they reached 85% of their maximum heart rate, calculated by age and sex. Fitter people are able to exercise for longer before reaching this level. This time was used to calculate people's total exercise capacity. People's heart rate and blood pressure were also monitored before and during the test.

The researchers excluded people from their first analysis if they already had cardiovascular disease, had been taking beta blockers (drugs that slow heart rate) or if they had dementia or any condition that could affect the brain scan or cognitive tests. They were also excluded if they were unable to complete the exercise test.

In their analyses, the researchers adjusted their figures to take account of the following confounders:

  • age
  • sex
  • the time between examinations
  • whether they smoked
  • whether they had diabetes
  • whether they had a gene linked to Alzheimer's disease
  • whether they took medicine to treat high blood pressure


What were the basic results?

People who had 20% lower fitness levels based on the exercise capacity test had smaller brain volumes when assessed in later life. Those with a higher heart rate and diastolic blood pressure while exercising also had smaller brain volumes. Higher systolic blood pressure was also linked to smaller brain volumes, but only when the researchers looked at the subset of people with high blood pressure.

There was no link between lower exercise capacity in mid-life and any measures of cognitive function (thinking ability) in later life.


How did the researchers interpret the results?

The researchers say their findings: "provide new evidence that lower cardiovascular fitness and elevated exercise blood pressure and heart rate responses in early to midlife are associated with smaller brain volumes nearly two decades later, thereby linking fitness over the life course to brain health in later life".

They say that encouraging people to be fit in middle age could improve healthy brain ageing, especially for people with raised blood pressure.



We already know that high blood pressure in mid-life is linked to increased chances of getting dementia in older age. Also, taking regular exercise in middle age has been linked to a lower chance of dementia.

This study adds to what we already know about links between having a healthy heart and circulation, and a healthy brain.

The study found that people who did well in fitness tests at around 40 years of age had fewer signs of brain shrinkage at around 60. However, this did not translate into signs that the brain was working less well – perhaps because people were not old enough to have shown signs of slowed cognitive function.

We don't know from the study whether fitness levels are directly linked to brain shrinkage in a causal fashion. Therefore we can't say whether any particular amount of exercise protects against brain shrinkage. However, the researchers suggest that better cardiovascular fitness provides better blood flow and oxygen delivery to the brain, helping to keep it healthy.

The study has some limitations; importantly, brain volume was only assessed once, at the end of life, so we don’t know how much people's total brain volume had changed over time. We don't know the likely effect of the differences in brain volume measured. Also, the researchers did not calculate the possible effects of carrying out many different calculations on one set of data, which can increase the likelihood of some findings being down to chance.

Exercise has so many benefits that it can be confidently recommended, despite any questions about this particular study. However, there is no 100% guarantee that healthy lifestyles, including exercise, can prevent dementia in later life.  

Links To The Headlines

Exercising in your forties could stop brain shrinking. The Daily Telegraph, February 11 2016

Being a couch potato SHRINKS the brain: Failing to exercise in your 30s and 40s is linked with dementia and early death. Daily Mail, February 11 2016

Links To Science

Spartano NL, Himali JJ, Beiser AS, et al. Midlife exercise blood pressure, heart rate, and fitness relate to brain volume 2 decades later. Neurology. Published online February 10 2016

Categories: NHS Choices

Scientists look at what puts the 'junk' into junk foods

NHS Choices - Behind the Headlines - Thu, 11/02/2016 - 12:00

"Scientists say they have cracked what makes processed foods… harmful,"  the Daily Mail reports. A small study suggests that processed foods that are high in "PAMPs" – pathogen-associated molecular patterns – may trigger inflammation inside the body.

PAMPs are molecules that are associated with infectious bacteria, so in the same way as an infection, they can trigger an immune response in the way of inflammation. And some experts suspect that prolonged inflammation can increase the risk of chronic diseases such as high blood pressure and type 2 diabetes.

This new study attempted to assess the relative benefits of a high-PAMP diet compared to a low-PAMP diet on a number of biomarkers associated with immune response.

The study, involving 24 healthy men over 11 days, tentatively suggested that PAMPs did act to trigger some biomarkers linked to an immune response – although the results weren't consistent.

Due to the size and shortness of the study its immediate implications are unclear.

There are also other limitations to consider. For example, the study didn't measure new cases of diabetes or cardiovascular disease, or any disease.

The assumption that the signs of raised inflammation seen in those given a high-PAMP diet are big enough to cause disease in the future is currently unproven.

The results of this study are intriguing, but represent points of interest for further study, not established facts or guidance.

Processed foods often have a high salt, sugar and fat content, so it is not a good idea to let them become a staple of your diet.

Where did the story come from?

The study was carried out by researchers from the University of Leicester (England) and was funded by University of Leicester Campbell Immunology Fund and the Higher Committee for Education Development in Iraq.

The study was published in the peer-reviewed medical journal Nutrition, Metabolism & Cardiovascular Diseases.

The Daily Mail's headline "Scientists say they have cracked what makes processed foods like burgers and ready meals harmful", seems to imply that the reason processed foods are unhealthy is some sort of mystery.

This downplays the many existing reasons why foods like burgers and ready meals are bad for your health; they are called "junk food" after all. Many ready meals contain lots of added sugar and salt to make them taste better, and can be high in fat. The fat and sugar can contribute to weight gain, which in turn increases your risk of many diseases.

A high-salt diet can raise your blood pressure, which elevates your risk of heart attacks and strokes. 

The added issue is that you might not be aware of the high levels of fat, salt and sugar in the foods, as not everyone pays attention to food labels.

This means you might be consuming levels likely to be harmful to health in the long run and not even know.


What kind of research was this?

This small study looked at the effects of dietary PAMPs on indicators of inflammation in a small group of healthy adult men over the course of just over a week.

Small and short studies like this do not set out to provide solid answers, or provide weighty proof. Instead they attempt to scratch the surface of a new research area, present new theories and kick up questions that bigger and better studies might be able to answer. As such, the results represent points of interest for further study, rather than established facts.


What did the research involve?

The research had two main parts.

The first part fed 11 healthy adult men (average age 38) two high-PAMP meals a day for four consecutive days while testing their blood before and after for signs of immune response changes. For the seven days before all men received diet advice to eat lower PAMP. This was because most men regularly consumed high-PAMP diets outside of the study so the researcher wanted to get everyone to a lower starting point. The rationale is that the impact of PAMP levels going from high to very high might be harder to detect than if it went from low to high. The men filled in food diaries to see if they were taking the advice.

The second part fed a group of 13 different healthy men (average age 28) onion bhajis made from freshly chopped onion and monitored the impact on blood inflammation measures for 24 hours. Two weeks of normal eating passed before the same men were asked to eat a nutritionally identical meal made from pre-chopped onions – high in PAMPs.

Any changes in weight circumference, blood cholesterol and blood fats were also measured.


What were the basic results?

The study team found that PAMPs were high in many processed foods such as lasagne and spaghetti bolognese ready meals, as well as baked pies, pasties and rolls.

Encouraging men to follow a low-PAMP diet for seven days appeared to reduce some signs of inflammation (their white blood cell count reduced by 12%), lowered their cholesterol (-0.69 mmol/l), and they managed to lose weight (-0.7kg), including averaging 1.6cm less around the waist. Their insulin sensitivity – as risk factor for diabetes – was unaffected. The four-day high-PAMP diet largely reversed these effects, expect the weight loss, which didn't fully return to starting levels. For example, the white blood cell count went back up by 14% and men put back around 1.2cm around their waists.

The study of nutritionally identical foods, differing only in their PAMP levels, showed high-PAMP foods made little difference to inflammatory markers 24 hours after eating. There were, however, signs the low-PAMP foods lowered inflammatory markers, for example, there were fewer white blood cells.


How did the researchers interpret the results?

The study team concluded that: "A low-PAMP diet is associated with reduced levels of several cardiometabolic risk factors, while a high-PAMP diet reverses these effects. These findings suggest a novel potential mechanistic explanation for the observed association between processed food consumption and risk of cardiometabolic diseases."



This small study tentatively suggests that processed foods high in PAMPs act to trigger an immune response in people that ultimately may raise the risks of type 2 diabetes and cardiovascular disease later in life.

At present these conclusions are very shaky. The study was small (just 24 healthy men took part) and short term (11 days), so gives us only the first loose threads of evidence about what's going on, rather than a more solid, clear picture.

For example, the study didn't measure new cases of diabetes or cardiovascular disease, or any disease. The link to disease rests on the assumption that the raised levels of inflammation seen in those given a high-PAMP diet will be big enough to cause disease in the future. This could be right or wrong, and needs testing to see if it holds true.

The first part of the study was also not controlled for other foods, which probably biased the results. The second part was much more controlled, and found very little immune impact after a high-PAMP meal – at least over 24 hours. More changes happened in the low-PAMP scenario.

The weight change might also be a red herring. It's not surprising that men who ate lots of junk food before the study lost a bit of weight after a week following advice to eat healthier (less than 1% of their body weights overall). But we certainly can't pin this weight change on the PAMPs, there were far too many other variables involved.

The results of this study are intriguing and represent points of interest for further study, not established facts.

Hopefully a larger study will follow to look further at this issue.

Links To The Headlines Revealed, the REAL reason junk food is so bad for us: Harmful molecules in chopped and refrigerated products raise the risk of heart disease and diabetes. Daily Mail, February 9 2016

Links To Science

Herieka M, Faraj TA, Erridge C. Reduced dietary intake of pro-inflammatory Toll-like receptor stimulants favourably modifies markers of cardiometabolic risk in healthy men. Nutrition, Metabolism & Cardiovascular Diseases. Published online December 18 2015

Categories: NHS Choices

Asset manager Henderson posts income boost despite market turmoil

Reuters UK Business News - Thu, 11/02/2016 - 10:21
LONDON (Reuters) - British asset manager Henderson Group posted forecast-beating net income on Thursday after retail investors flocked to its funds even as markets remained beset by concerns over global growth.

Tate & Lyle warns of lower profit due to currency hit

Reuters UK Business News - Thu, 11/02/2016 - 10:18
(Reuters) - Tate & Lyle Plc , the British food ingredients maker, said it expected full-year reported adjusted pretax profit to be "modestly below" a year earlier, hurt by the drop in values of the Mexican peso and the Brazilian real.

Thomas Cook says bookings recovering after security concerns

Reuters UK Business News - Thu, 11/02/2016 - 10:07
LONDON (Reuters) - Tourism group Thomas Cook said bookings were recovering after customers delayed making holiday plans following terror attacks in Paris last November and in Istanbul in January, which has caused demand for trips to Turkey to plunge.

HSBC cancels 2016 pay freeze - memo from CEO Gulliver

Reuters UK Business News - Thu, 11/02/2016 - 10:06
LONDON (Reuters) - Europe's largest lender HSBC has cancelled its planned 2016 pay freeze, although it is keeping a hiring freeze in place, a memo from chief executive Stuart Gulliver seen by Reuters said on Thursday.

Glencore steps up debt-reduction plan, reports drop in copper output

Reuters UK Business News - Thu, 11/02/2016 - 09:50
LONDON (Reuters) - Glencore has taken another step to reduce its debt by selling $500 million of future precious metals output and reported a drop in production of its most lucrative product, copper.

Oil falls on U.S. supply record, weak demand outlook

Reuters UK Business News - Thu, 11/02/2016 - 09:32
LONDON (Reuters) - Oil slid on Thursday, dented by record U.S. crude inventories at the Cushing delivery point, worries about the demand outlook, and as Goldman Sachs said prices would remain low and volatile until the second half of the year.

Publicis sees modest growth in 2016 after strong final quarter

Reuters UK Business News - Thu, 11/02/2016 - 09:18
PARIS (Reuters) - France's Publicis predicted modest underlying growth for 2016 but avoided setting precise full-year targets as it digests a $3.7 billion (2.5 billion pounds) acquisition and reorganises its businesses.

Record production, high refining margins lift Total profit

Reuters UK Business News - Thu, 11/02/2016 - 09:06
PARIS/LONDON (Reuters) - Record upstream production and high refining margins in Europe helped Total report better-than-expected fourth-quarter net profit but the company said it planned to cut costs and reduce spending further due to prolonged low oil prices.

Emerging market rout dents Ashmore profit, shares drop

Reuters UK Business News - Thu, 11/02/2016 - 08:58
LONDON (Reuters) - A slide in emerging markets hit first-half underlying profit at emerging markets-focused fund manager Ashmore , dragging its shares down by 5 percent on Thursday.

Rio Tinto ditches boom time payout policy as profit plunges

Reuters UK Business News - Thu, 11/02/2016 - 08:41
MELBOURNE/SYDNEY (Reuters) - Rio Tinto scrapped its generous payout policy in the face of a bleak outlook for the global economy after it slumped to a net loss for 2015 and posted its worst underlying earnings in 11 years.

Brtitain's Johnston Press in talks to buy newspaper 'i'

Reuters UK Business News - Thu, 11/02/2016 - 08:24
(Reuters) - Britain's Johnston Press is in late-stage talks on a deal to buy Independent Print's "i" newspaper, it said on Thursday, raising questions about the future of the latter's sister publication, The Independent.

Nokia posts strong network result, warns over China slowdown

Reuters UK Business News - Thu, 11/02/2016 - 07:51
HELSINKI (Reuters) - Finland's Nokia reported better-than-expected profits for its mainstay telecom network equipment business but warned that rollouts for new mobile networks would start to slow this year in its most vital market China.

Tobacco group Imperial Brands increases revenue despite sales volume fall

Reuters UK Business News - Thu, 11/02/2016 - 07:29
LONDON (Reuters) - British tobacco company Imperial Brands posted a rise in first-quarter revenue despite volume declines, particularly in Iraq and Syria, helped by price increases in several markets.

SocGen raises litigation provisions, highest annual revenue since 2010

Reuters UK Business News - Thu, 11/02/2016 - 07:19
PARIS (Reuters) - Societe Generale posted a lower than expected rise in fourth-quarter net income on Thursday after it set aside an additional 400 million euros ($450.4 million) to cover litigation costs.

The banker at centre of Swiss bank BSI, 1MDB relationship

Reuters UK Business News - Thu, 11/02/2016 - 07:16
SINGAPORE (Reuters) - A private banker, caught up in Singapore's money laundering probe linked to 1Malaysia Development Bhd, was a key link between the embattled state investor, a Swiss private bank and a Malaysian businessman connected to the troubled fund.

Yen, bonds, gold all gain at dollar's expense, stocks sag

Reuters UK Business News - Thu, 11/02/2016 - 06:35
SYDNEY (Reuters) - Fresh cracks appeared in global markets on Thursday as investors sought the safety of Japanese yen, gold and top-rated bonds while dumping U.S. dollars on bets the Federal Reserve could be done raising interest rates.

Global code aims to tell currency traders what to say, and what not

Reuters UK Business News - Thu, 11/02/2016 - 06:05
LONDON (Reuters) - The first draft of a new global code of conduct for the $5 trillion a day currency market seeks to define better what traders can and cannot say to one another.

Suffolk Police praised in new report out today following independent inspection

Newmarket Journal - Thu, 11/02/2016 - 06:00

Suffolk Police have been praised and ranked as ‘good’ in a new report from Her Majesty’s Inspectorate of Constabulary (HMIC) released today, Thursday February 11.

Categories: Local Press