Conjugated linoleic acid supplementation for the same length of time, on the other hand, reduced total body fat and lowered the women’s body mass index (BMI), a common health measure of weight relative to height.
All of the women in the study took one oil for 16 weeks, followed by the other oil for an equal amount of time.
Is the explosive growth of obesity worldwide being triggered by an infectious agent? Investigators are closing in on the role of oral bacteria as a potential direct contributor to obesity.
J.M. Goodson and colleagues, who carried out a recent study, measured salivary bacterial populations of overweight women.
Saliva was collected from 313 women with a body mass index (BMI, weight to height ratio) between 27 and 32 and bacterial populations were measured by DNA probe analysis. A BMI above 25 is a sign of being overweight.
Levels in this group were compared with data from a population of 232 healthy individuals from periodontal disease studies.
Analysis of saliva revealed that 98.4% of the obese women could be identified by the presence of a single bacterial species (Selenomonas noxia) at levels greater than 1.05% of the total salivary bacteria.
Analysis of these data suggests that the composition of salivary bacteria changes in overweight women.
It seems likely that these bacterial species could serve as biological indicators of a developing overweight condition.
Of even greater interest, and the subject of future research, is the possibility that oral bacteria may participate in the pathology that leads to obesity, said a International and American Associations for Dental Research release.
The study was published in the June issue of the Journal of Dental Research.
Carrying four stones of excess weight can cost you three years of life, warn researchers.
A study of almost a million adults has given the clearest indication yet of the mortal dangers of obesity.
Those who are extremely overweight could lose ten years of their life, it says.
New research has shown that people who are carrying too much weight are taking years off their lives
.Scientists from Oxford University assessed the impact of obesity by analysing data from 57 separate studies.
They found a clear link between high body mass index scores and an early grave.
Using BMI gives a good measure of how overweight a person is, because it compares weight to height.
But the scientists also gave an estimate of how much excess weight could be dangerous compared with an ‘ideal’ weight.
Co-researcher Dr Gary Whitlock said ‘Excess weight shortens human lifespan.
‘In countries like Britain and America, weighing a third more than the optimum shortens lifespan by about 3 years.
‘For most people, a third more than the optimum means carrying 20 to 30 kilograms – 50 to 60 pounds, or 4 stone – of excess weight.
‘If you are becoming overweight or obese, avoiding further weight gain could well add years to your life.’
Official UK figures show nearly one in four adults is obese, 38 per cent are overweight and children are rapidly piling on the pounds.
The relentless rise in the obesity epidemic means the number of adults tipping the scales as dangerously overweight has almost doubled over the last 10 years.
The National Audit Office estimates obesity causes at least 30,000 deaths a year in the UK, through conditions such as cancer, heart disease, strokes and diabetes.
It costs the NHS at least £500million a year to treat and the wider economy £2billion.
The BMI measurement is used to calculate whether a person is a
healthy weight, in which an individual divides weight (in kilos) by the square of their height (in metres).
Under 18.5 is underweight, 18.5-25 is healthy weight, 25-30 is overweight, 30-35 is obese and over 35 is very obese.
The study found having a BMI above the ‘ideal’ range of 22.5 to 25 led to higher death rates.
Above BMI of 25, each additional five units on the BMI scale increased overall mortality by around a third.
The investigation, called the Prospective Studies Collaboration, pooled information on 894,576 adults mostly from western Europe and North America with an average age of 46 and an average BMI of 25.
As well as looking at overall death rates, the researchers linked BMI scores with common causes of death through ill health.
Each additional five BMI units corresponded with a 40 per cent increase in deaths from heart and artery disease and strokes.
The same rise in BMI led to an increase in deaths of between 60 per cent and 120 per cent from diabetes and liver or kidney disease, 10 per cent more from cancer, and one-fifth rise from lung disease.
‘Moderate’ obesity, which is now common in western countries in the BMI range of 30 to 35, reduced survival by between two and four years.
Severe obesity in the 40 to 45 BMI range cut lifespans by eight to 10 years, comparable to the effects of smoking, said co-researcher Professor Sir Richard Peto.
The authors stressed even overweight people who cannot slim could extend their lives by avoiding further weight gain.
‘In adult life, it may be easier to avoid substantial weight gain than to lose that weight once it has been gained’ says the report.
It says that by avoiding a further increase from a BMI of 28 to 32, a typical person in early middle age would gain about two years of life expectancy.
Alternatively, by avoiding an increase from BMI of 24 to 32 – a third above the apparent optimum – a young adult would on average gain about three extra years of life, it says.
Dr David Haslam, chairman of the National Obesity Forum, said ‘This is a very good study from a first-class institution.
‘It tells us that obesity is going to cut your life short and kill you from a number of diseases, ranging from diabetes through to cardiovascular disorders.
‘Everyone knows that smoking is bad for you, and we’ve seen clear evidence of the health risks over the last 50 years.
‘But the obesity epidemic hasn’t been with us for long enough to see the really bad effects on health in later life and the premature deaths.
‘The message is getting through about smoking and I hope we’ll see the same with obesity.’
Iribarren and his team tested whether sagittal abdominal diameter, or SAD, which is the distance from the back to the upper abdomen midway between the top of the pelvis and the bottom of the ribs, would improve the accuracy of BMI (body mass index) in predicting heart disease risk.
Men with the largest SAD were 42% more likely to develop heart disease during follow-up compared to those with the smallest SAD, while a large SAD increased heart disease risk by 44% for women.