Friday, 30 May 2014

FTO 'fat gene' may make people more impulsive

reposted from:
crabsallover highlightskey pointscomments / links.
"Carriers of the FTO gene are more likely to succumb to impulsive hunger pangs and prefer high-calorie foods," the Mail Online reports.
A study of carriers of a variant of the FTO gene found reduced activity in areas of the brain associated with impulse control. This was associated with changes in weight, brain function, impulse eating and dietary intake as people got older.
All humans carry the FTO gene, a gene involved in appetite. There is a wide body of research that suggests that certain "high-risk" variants of FTO make people more vulnerable to becoming obese as they get older. It is still unclear why this is the case.
Brain scans suggest that carriers of a specific high-risk variant – rs1421085 – appeared to have decreased brain activity in areas of the brain associated with impulse control. The carriers may also have a "hardwired" preference to find eating high-fat food more enjoyable. Ongoing research did find that these carriers were more likely to become obese as they got older.
This study gives us more information about whether or not some people may have a genetic predisposition towards becoming overweight or obese, and why. It does not mean that this is inevitable, nor does it show that some people are genetically unable to resist impulse eating. 
Whatever your genes, you can maintain a healthy weight. Why not try the NHS Choices 12-week diet and exercise plan?

Where did the story come from?

The study was carried out by researchers from the National Institute on Aging, Florida State University, and Johns Hopkins Medical Institutions in the US.
It was funded by the US National Institute on Aging and published in the peer-reviewed journal, Molecular Psychiatry.
The Mail Online's coverage was fatalistic in tone, implying that people with the "obesity gene" are unable to do much about their impulse eating or their weight.
But this study does not show that impulse eating is determined by our genes. It did not look at actual impulse eating, only self-reported "impulsivity" as a personality trait.
While brain scans were used to study areas of the brain associated with impulse control, at present this is a very inexact diagnostic tool. Brain scans certainly cannot prove that a person is genetically predisposed to impulse eating.
The true picture of obesity is far more complex. It is likely that there are many genes associated with obesity, some of them still unidentified. The study looked at only one particular variant in one of these genes. 
There are also environmental factors to consider. The United States is notorious for being an obesogenic environment. This is an environment that makes inhabitants more prone to obesity because of a number of factors, such as the ready availability of cheap, energy-rich food and lack of opportunities to exercise.

What kind of research was this?

This was a cohort study of ageing which looked at what happened to people who carried a particular variation (rs1421085) in a gene known as the FTO gene as they aged.
This variation has been found to be associated with obesity in children and young people. Less research has been done on its effect in older people or on weight changes over time. The variant has also been found to be associated with mental health disorders and brain shrinkage in older people.
The researchers say that the biological basis of obesity-related behaviour is poorly understood. Overweight people are sometimes portrayed as being weak-willed and unable to control their eating.
However, the researchers argue that it is unclear whether a common biological mechanism underlies a predisposition to obesity, as well as impulse behaviour and a preference for calorie-dense foods.
They wanted to see if the FTO gene variant was associated with changes in body mass index (BMI), as well as changes in brain function and personality traits such as "impulsivity", as people grew older.

What did the research involve?

The researchers used a large long-running US study of ageing, which began in 1958. They identified which participants carried the FTO gene variant and which did not, and compared their BMIs, brain function and personality traits over time.
People carry two copies of any given gene, so participants were tested for whether they carried one or two copies of the FTO gene variant. They also underwent detailed examinations, including neuropsychological assessments and neurological, laboratory and radiological tests every two years.
The participants' height and weight was measured at each visit to determine changes in their BMI as they got older. They were also asked details about their physical activity.
A subset of participants also underwent regular brain scans, which began in 1994, to measure changes in blood flow to different parts of the brain and changes in brain function. The researchers were particularly interested in parts of the brain known to be involved in controlling impulses and response to taste.
Personality traits were also assessed as people aged using a validated 240-item questionnaire. For their current analysis, the researchers primarily focused on the personality traits of impulsivity, excitement-seeking, self-discipline and deliberation. These traits were assessed because they could potentially affect eating behaviour.
Dietary intake was assessed by seven-day dietary records reported by the participants and collected during four time periods – 1961-65, 1968-75, 1984-91 and 1993-2005. The participants were trained in the procedure for completing these records – such as how to assess portion size – by dietitians.
The final sample analysed in this study consisted of 697 participants who were cognitively normal (those with dementia or mild cognitive impairment were excluded). Their average age was 45 at the start of the study, and they had been followed up for between 11 and 35 years (average 23 years).
The analyses took into account factors (confounders) such as age, race, education and cardiovascular risk that might influence the results.

What were the basic results?

The researchers found that about 20% of the study's participants had two copies of the obesity-related FTO gene variant, and 48% carried one copy.
They found that over time, changes to BMI as people got older were significantly different between carriers and non-carriers of the gene variant.
Peak BMI (the highest BMI a person reached during the study) was highest in those with two copies of the variant, intermediate in those with one copy, and lowest in non-carriers. The difference appeared relatively small.
The researchers also found that carriers of the variant were more likely than non-carriers to have reduced activity in certain parts of the brain as they grew older. This included an area involved in impulse control.
They found that measures of impulsivity decreased over time in both carriers and non-carriers, while the trait of deliberation increased. However, the presence of the FTO gene variant was associated with less of a decline in excitement-seeking, with the largest effect found in those with two copies of the variant.
On dietary patterns, they found that all participants reported eating less fat and more carbohydrates over time. However, the presence of the obesity-related variant was associated with less of a decline in fat intake. It was also associated with less of an increase in carbohydrate intake.
Again, the effects were strongest in those with two copies of the variant, who showed some increase in fat intake at older ages.

How did the researchers interpret the results?

The researchers conclude that it is possible that the FTO gene may have an influence on brain function, personality and diet in older people.
They suggest that changes in brain function shown in the study may be associated with increasing impulsivity and greater preference for dietary fat among carriers.


This study has tried to further our understanding of how variations in the FTO gene associated with obesity result in people being overweight or obese. It found that a variation in the FTO gene was associated with BMI changes over time, as well as with changes in the brain and in impulsivity and diet as people age.
This genetic variant was already known to be associated with obesity, but this study is one of the few to look at changes over time. However, this study did not examine whether people were inclined to eat on impulse objectively, instead relying on participants reporting impulsivity as a personality trait themselves.
The researchers suggest that genetic variant-related changes in brain function may be linked to an increase in impulse eating, but at present this is just speculation.
The true picture of obesity is likely to be very complex. It is likely that there are many genes associated with obesity, some of them still unidentified, and that they work in different ways.
The study looked at only one particular variant in one of these genes. Carrying this single genetic variant is not a guarantee that a person will become overweight or obese, or that they cannot eat a healthy diet.
Research on the causes of obesity and on why some people may be predisposed to it is important. This study may be of interest to specialists, but as yet it does not really help anyone trying to keep to a healthy weight as they grow older.
There's no question that for many people this is a struggle, but a healthy diet and regular exercise is within everyone's reach. If you are having problems coping with cravings, there are low-calorie snacks that can help you feel full without derailing your diet. 

Analysis by 
Bazian. Edited by NHS ChoicesFollow Behind the Headlines on TwitterJoin the Healthy Evidence forum.

Links to the headlines

Links to the science

Chuang YF, Tanaka T, Beason-Held LL, et al. FTO genotype and aging: pleiotropic longitudinal effects on adiposity, brain function, impulsivity and diet. Molecular Psychiatry. Published online May 27 2014

NICE: 'Obese should be prescribed slimming clubs'

reposted from:
crabsallover highlightskey pointscomments / links.

“GPs told to prescribe £100 slimming courses for millions of obese patients,” the Daily Mail reports.
The news is based on new guidelines from the National Institute for Health and Care Excellence (NICE) that aim to encourage sustainable weight loss in the obese; “lose a little, and keep it off”.
The guidance is mainly aimed at commissioners (who plan and agree which services will be provided in the NHS and monitor them), health professionals and groups who provide lifestyle weight management programmes. The recommendations may also be of interest to members of the public, including people who are overweight or obese.
The guidance has been issued because being overweight or obese is a common and important health problem in the UK. In 2012 about a quarter of men and women aged 16 and over in England had a body mass index (BMI) over 30, classified asobese.
In addition, 42% of men and 32% of women were categorised as overweight (BMI of 25 to 30). Life expectancy is estimated to be reduced by an average of two to four years for people with a BMI of 30 to 35, and eight to 10 years for a BMI of 40 to 50.
The cost of obesity to society was estimated to be almost £16 billion in 2007, which is predicted to rise to £50 billion by 2050 if obesity levels continue to rise.
NICE has estimated that across the population, a 12-week weight management programme costing £100 or less for people who are overweight or obese would be cost-effective if they were to lose at least 1kg and keep the weight off for life.

What are the main recommendations?

NICE recommends that local authorities and clinical commissioning groups should provide access for people to be referred to a range of lifestyle weight management schemes.
GPs, practice nurses, health visitors, pharmacists and the local adult population should be informed of what services are available locally. And they are advised to use informed advice from the NHS Choices website on weight management.
GPs, health and social care professionals are advised to raise the issue of weight loss for overweight and obese adults in a non-judgemental way. They should consider referring adults of any age to local programmes. They should take the person’s preferences into account. but choose group programmes where possible as they provide better value for money. The programmes should be able to show that at least 60% of people are likely to complete them and that they are likely to lead to an average loss of at least 3% of body weight, with a minimum of 30% of people losing 5% of their initial weight.
People should be referred who have:
  • BMI over 30 (or lower for people from black and minority ethnic groups as they have a higher risk of type 2 diabetes), or people with other risk factors such as already having diabetes
  • BMI between 25 to 30 if there is enough local resource
GPs, health and social care professionals and providers of lifestyle weight management services should be trained to deliver multicomponent programmes, tailored to the individual needs of the person. The programmes should have been developed by a multidisciplinary team including a registered dietician, registered psychologist and qualified physical activity instructor. The programme should be collaborative, and cover:
  • dietary habits
  • safe physical activity
  • strategies to achieve behaviour change
  • prevention of weight regain
Commissioners and local authorities should regularly monitor the provision of services and how effective they have been in helping people to lose weight to ensure that the measures are working and are providing good value for money (are cost effective). This includes collecting outcomes such as:
  • the percentage of people losing more than 3% or 5% of their baseline weight
  • how the weight changes in the 12 months after the programme is completed
  • changes in other outcomes such as blood pressure

What are the main benefits of weight loss?

The more weight that is lost, the greater the benefits – especially if a person is able to lose 5% to 10% of their body weight, and maintain it. However, even losing just 3% body weight if obese or overweight can be beneficial.
Weight loss reduces the risk of:
Read more about the complications of obesity.

What are the dangers of rapid weight loss?

Setting realistic goals for weight loss is an important part of the NICE recommendations. This is to ensure a steady rate of weight loss within safe limits, and to increase chances that the weight loss can be maintained, rather than having weight regain. 

The dangers of rapid weight loss include feeling tired and unwell, as well as the potential for more serious complications such as malnutrition and gallstones. The recommended safe level of weight loss to aim for is between 0.5kg and 1kg per week.

How accurate and balanced is the media’s reporting of the guidelines?

The media have accurately described the extent of people being overweight and obese in the UK, and the cost of treating obesity-related illnesses. They have also highlighted the risks of obesity and the benefits of long term weight loss.
Arguably some of the papers have missed the point of NICE’s main arguments. That is while funding weight-loss programmes may cost the NHS money in the short-term (the Daily Mail quotes a figure of a £100 million a year, but it is unclear how it came up with the figure), it could potentially save the NHS billions of pounds in the long-term. This remains to be proven. 

The NHS weight loss plan

NHS Choices provides a downloadable 12 week weight loss plan that:
  • promotes safe and sustainable weight loss
  • helps you learn how to make healthier food choices
  • provides support from our online community
  • offers a weekly progress chart 
  • presents an exercise plan to help you lose weight
  • hopefully allows you to learn skills to prevent regaining weight
Analysis by Bazian. Edited by NHS ChoicesFollow Behind the Headlines on TwitterJoin the Healthy Evidence forum.

Monday, 12 May 2014

ONS suggests that one in four deaths are 'avoidable'

reposted from:
crabsallover highlightskey pointscomments / links.

“1 in 4 deaths could have been prevented,” The Times reports. Figures released by the Office for National Statistics (ONS) found that 23% of deaths could have been prevented through better care, more effective treatment and healthier living.
The news is based on an ONS bulletin titled Avoidable Mortality in England and Wales, 2012 (PDF 186kb).
The bulletin provides mortality figures for causes of death that are considered avoidable if timely and effective healthcare is received or healthier lifestyle choices adopted.
Figures were provided for the period 2001 to 2012 so that trends can be seen.
The bulletin found that deaths from potentially avoidable causes accounted for about 23% of all registered deaths in England and Wales in 2012. While one avoidable death is one too many, there was a downward trend as this rate has fallen from 25% in 2003.
The report also found that:
  • avoidable death rates were higher in Wales than England
  • the leading causes of avoidable deaths were ischaemic heart disease (the most common type of heart disease) in males, and lung cancer in females
  • the neoplasms (cancers and non-cancerous abnormal tissue growths) that are considered to be avoidable have overtaken cardiovascular diseases as the leading cause of avoidable deaths since 2007
According to the report, a degree of caution should be used when interpreting the findings. This is due to factors such as advances in healthcare and policy not being reflected in mortality rates in the short term.

The NHS Health Check

If you are aged 40 or above then you are eligible for a NHS Health Check.

The NHS Health Check is a sophisticated check of your heart health. Aimed at adults in England aged 40 to 74, it checks your vascular or circulatory health and works out your risk of developing some of the most disabling – but preventable – illnesses, such as heart disease, diabetes anddementia.

Read more about the NHS Health Check.

Where did the story come from?

The report was carried out by the UK Office for National Statistics (ONS). Statistics on avoidable deaths are used by governments, public health experts, academics and charitable organisations to reduce the amount of specific conditions considered avoidable causes of death.
According to the report, it is anticipated that the statistics provided will help in assessing the quality and performance of healthcare as well as wider public health policies. However, several limitations listed in the report are described further below and the report states a degree of caution is required when interpreting the findings.
The ONS is a government body that provides data on the economy and population at a national and local level. Summaries and detailed data are released free of charge.

What did the report base its findings on?

The report provides mortality (death) figures for causes of death that are considered avoidable if timely and effective healthcare or public health interventions are received.
Figures are provided for both England (including the regions of England) and Wales for the period 2001 to 2012 and trends are reported.
The report has presented the statistics using age-standardised rates, which is a standard method for carrying out calculations on mortality rates. This makes allowances for differences in the age structure of the population over time and between genders.
Statistics on mortality are taken from the information provided when deaths are certified or registered (in England and Wales deaths should be registered within five days of the death occurring).

What are the main findings of the report?

The key findings of the report are:
  • deaths from potentially avoidable causes accounted for about 23% (112,493 out of 499,331) of all registered deaths in England and Wales in 2012 (in 2003 this figure was 25%, so deaths from avoidable causes since 2003 have actually decreased)
  • avoidable death rates were significantly higher in Wales than England for the period 2001 to 2012
  • avoidable death rates varied across the regions of England with the highest in the North of England and the lowest in the South and East of England for the period 2001 to 2012
  • for the period 2001 to 2006, cardiovascular diseases were the leading contributors to avoidable deaths. However since 2007, neoplasms (cancers and non-cancerous abnormal tissue growths) that are considered to be avoidable have taken over as the leading cause of avoidable deaths and there has been no significant decrease in the death rate from neoplasms since 2009
  • in males, the leading cause of avoidable death was ischaemic heart disease (representing 22% of all avoidable male deaths)
  • in females, lung cancer was the leading cause of avoidable death (representing 15% of all avoidable deaths in females)

What are the limitations of the report?

According to the report, one of the main difficulties in producing an indicator of avoidable deaths is the selection of the causes of death to be included. While a particular condition can be considered avoidable, the report says this does not mean that every death from that condition could be prevented. This is due to factors such as the age of the patient, the extent of disease progression at diagnosis or the existence of other medical conditions that are not taken into account when compiling a list of causes.
Another limitation the report lists is that improvements in the healthcare system (such as a change in resources or the introduction of a new healthcare innovation or policy) may not equate to immediate changes in death figures in the short term and that this is sometimes mistakenly interpreted as a decrease in healthcare quality.

How can you reduce your risk?

The good news about reducing your risk for one avoidable condition is that it often leads to a reduction in risk for other conditions. For example, if you make an effort to reduce your heart disease risk through exercise and healthy eating, this will also reduce your risk of stroke, diabetes and kidney disease.
Proven methods of reducing your risk of avoidable conditions include:
Analysis by Bazian. Edited by NHS ChoicesFollow Behind the Headlines on TwitterJoin the Healthy Evidence forum.

Links to the headlines

Further reading

Office for National Statistics. Avoidable Mortality in England and Wales, 2012. May 2014