Obesity not synonymous with ill-health?

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Obese people can be just as healthy and fit as their slimmer counterparts, with no greater risk of developing or dying from cardiovascular disease or cancer, says the largest study so far on the subject. The findings show a subset of obese people who are metabolically healthy – they don’t suffer from conditions such as insulin resistance, diabetes and high cholesterol or blood pressure – and who have a higher level of fitness, as measured by how well the heart and lungs perform, than other obese people.
Being obese does not seem to have a detrimental effect on their health, and doctors should bear this in mind when considering what, if any, interventions are required, say researchers, the European Heart Journal reported. «It is well known that obesity is linked to a large number of chronic disease such as cardiovascular problems and cancer. However, there appears to be a sub-set of obese people who seem to be protected from obesity-related metabolic complications,» said the first author of the study, Francisco Ortega, from the department of biosciences and nutrition, Karolinska Institutet, Stockholm, Sweden.
«They may have greater cardio-respiratory fitness than other obese individuals, but, until now, it was not known the extent to which these metabolically healthy but obese people are at lower risk of diseases or premature death,» said Ortega. Ortega is currently a research associate affiliated to the Department of Physical Activity and Sport, University of Granada (Spain); but the project and investigation took place at the University of South Carolina (Columbia) under the direction of Steven Blair, professor who is responsible for the long-running «Aerobics Centre Longitudinal Study» (ACLS) which provided the 43,265 participants for this current analysis.
Ortega and his colleagues found that 46 percent of the obese participants were metabolically healthy. After adjusting for several factors, including fitness, metabolically healthy but obese people had a 38 percent lower risk of death from any cause than their metabolically unhealthy obese peers, according to a South California statement. The risk of developing or dying from cardiovascular disease or cancer was reduced by between 30-50 percent for the metabolically healthy but obese people, and there were no significant differences observed between them and the metabolically healthy, normal weight participants.
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Obesity not synonymous with ill-health?

Escrito por

Obese people can be just as healthy and fit as their slimmer counterparts, with no greater risk of developing or dying from cardiovascular disease or cancer, says the largest study so far on the subject. The findings show a subset of obese people who are metabolically healthy – they don’t suffer from conditions such as insulin resistance, diabetes and high cholesterol or blood pressure – and who have a higher level of fitness, as measured by how well the heart and lungs perform, than other obese people.
Being obese does not seem to have a detrimental effect on their health, and doctors should bear this in mind when considering what, if any, interventions are required, say researchers, the European Heart Journal reported. «It is well known that obesity is linked to a large number of chronic disease such as cardiovascular problems and cancer. However, there appears to be a sub-set of obese people who seem to be protected from obesity-related metabolic complications,» said the first author of the study, Francisco Ortega, from the department of biosciences and nutrition, Karolinska Institutet, Stockholm, Sweden.
«They may have greater cardio-respiratory fitness than other obese individuals, but, until now, it was not known the extent to which these metabolically healthy but obese people are at lower risk of diseases or premature death,» said Ortega. Ortega is currently a research associate affiliated to the Department of Physical Activity and Sport, University of Granada (Spain); but the project and investigation took place at the University of South Carolina (Columbia) under the direction of Steven Blair, professor who is responsible for the long-running «Aerobics Centre Longitudinal Study» (ACLS) which provided the 43,265 participants for this current analysis.
Ortega and his colleagues found that 46 percent of the obese participants were metabolically healthy. After adjusting for several factors, including fitness, metabolically healthy but obese people had a 38 percent lower risk of death from any cause than their metabolically unhealthy obese peers, according to a South California statement. The risk of developing or dying from cardiovascular disease or cancer was reduced by between 30-50 percent for the metabolically healthy but obese people, and there were no significant differences observed between them and the metabolically healthy, normal weight participants.
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You can be both fat and fit: Study

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Nearly half of overweight people per se are physically fit and healthy and at no greater risk of heart disease or cancer, than their slim peers, researchers claim. According to experts, the key is being «metabolically fit» , meaning no high blood pressure, cholesterol or raised blood sugar, and exercising.

Looking at data from over 43,000 US people they found that being overweight per se did not pose a big health risk, the BBC News reported.
More than a third of the participants were obese in the study conducted at the University of South Carolina.
Of these 18,500, half were assessed as metabolically healthy after a physical examination and lab tests.
This subset of metabolically healthy obese people who did not suffer from conditions such as diabetes, high cholesterol or high blood pressure , were generally fitter and exercised more than the other obese people . Their risk of developing or dying from cardiovascular disease or cancer was identical to people of ideal weight and was half that of «metabolically less fit» obese people.
Lead researcher Dr Francisco Ortega , who currently works at the University of Granada in Spain, said the findings show that getting more exercise can keep you healthier, even if you still carry a bit of extra weight.
«It is well known that obesity is linked to a large number of chronic disease like cardiovascular problems and cancer. However, there appears to be a sub-set of obese people who seem to be protected from obesity-related metabolic complications,» he said.
Most of the participants came from a similar background, meaning the results may not apply to everyone. They were mostly Caucasian, well educated, and worked in executive or professional positions.
«In the majority of cases, obesity is an undeniable risk factor for developing coronary heart disease. However , these studies remind us that it is not always your weight that’s important , but where you carry fat and also how it affects your health and fitness ,» Amy Thompson, of the British Heart Foundation, said.

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You can be both fat and fit: Study

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Nearly half of overweight people per se are physically fit and healthy and at no greater risk of heart disease or cancer, than their slim peers, researchers claim. According to experts, the key is being «metabolically fit» , meaning no high blood pressure, cholesterol or raised blood sugar, and exercising.

Looking at data from over 43,000 US people they found that being overweight per se did not pose a big health risk, the BBC News reported.
More than a third of the participants were obese in the study conducted at the University of South Carolina.
Of these 18,500, half were assessed as metabolically healthy after a physical examination and lab tests.
This subset of metabolically healthy obese people who did not suffer from conditions such as diabetes, high cholesterol or high blood pressure , were generally fitter and exercised more than the other obese people . Their risk of developing or dying from cardiovascular disease or cancer was identical to people of ideal weight and was half that of «metabolically less fit» obese people.
Lead researcher Dr Francisco Ortega , who currently works at the University of Granada in Spain, said the findings show that getting more exercise can keep you healthier, even if you still carry a bit of extra weight.
«It is well known that obesity is linked to a large number of chronic disease like cardiovascular problems and cancer. However, there appears to be a sub-set of obese people who seem to be protected from obesity-related metabolic complications,» he said.
Most of the participants came from a similar background, meaning the results may not apply to everyone. They were mostly Caucasian, well educated, and worked in executive or professional positions.
«In the majority of cases, obesity is an undeniable risk factor for developing coronary heart disease. However , these studies remind us that it is not always your weight that’s important , but where you carry fat and also how it affects your health and fitness ,» Amy Thompson, of the British Heart Foundation, said.

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‘Fitness’ and ‘Fatness’ Unrelated: Obesity not a Factor in Some People’s Health

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Contrary to popular prognosis, Just because a person is fat does not mean their not fit.
According to a controversial study published online in the European Heart Journal, obesity does not necessarily determine a persons metabolic health and fitness.

Dr Francisco Ortega (PhD), a research associate affiliated to the Department of Physical Activity and Sport, University of Granada (Spain), and at the Department of Biosciences and Nutrition, Karolinska Institute in Stockholm, Sweden conducted a study under the direction of Professor Steven Blair, who is responsible for the long-running «Aerobics Center Longitudinal Study» (ACLS).

According to the study,43,265 clinically obese participants were recruited to the ACLS and studied between 1979 and 2003. They completed a detailed questionnaire, including information on their medical and lifestyle history, and they had a physical examination that included a treadmill test to assess cardio-respiratory fitness and measurements of height, weight, waist circumference, and their percentage of body fat. Blood pressure, cholesterol and fasting glucose levels were also measured. The study participants were followed until they died or until the end of 2003.
Results suggested that there are a subset of obese people who are metabolically healthy — they don’t suffer from conditions such as insulin resistance, diabetes and high cholesterol or blood pressure — and who have a higher level of fitness, as measured by how well the heart and lungs perform, than other obese people.
Obesity in itself did not have a detrimental effect on their health, and researchers say doctors should bear this in mind when considering what, if any, interventions are required, say the researchers.
«It is well known that obesity is linked to a large number of chronic diseases such as cardiovascular problems and cancer. However, there appears to be a sub-set of obese people who seem to be protected from obesity-related metabolic complications,» said Dr Ortega, first author of the study.
Many medical practitioners omit the fact that common obesity related health complications are in fact genetically determined. Persons diagnosed with diabetes, cardio-vascular diseases or even cancer are genetically predisposed to such issues (i.e. it runs in the family) and medical history should be the primary determinant of whether or not a person’s weight is a causal or sustaining factor in these issues.
The findings showed 46% of the obese participants were metabolically healthy with a 38% lower risk of death from any cause than their metabolically unhealthy obese peers. The risk of developing or dying from cardiovascular disease or cancer was reduced by between 30-50% for the metabolically healthy but obese people, and there were no significant differences observed between them and the metabolically healthy, normal weight participants.
«There are two major findings derived from our study. Firstly, a better cardio-respiratory fitness level should be considered from now on as a characteristic of this subset of metabolically healthy obese people. Secondly, once fitness is accounted for, our study shows for the first time that metabolically healthy but obese individuals have similar prognosis as metabolically healthy normal-weight individuals, and a better prognosis than their obese peers with an abnormal metabolic profile,» The authors write.
The only common ailment among obese women, regardless of their level of physical fitness is a delayed period. However, even normal weight women can have the same issue and both groups can be regulated with birth control.
It is well known that maintaining a healthy weight is one of the ways to avoid developing heart problems. However, as a result of another study which found that overweight and obese people had a much lower mortality rate than underweight or morbidly obese persons, the authors claim:
«We believe that no evidence exists that proves weight reduction in itself has a positive prognostic value after ACSs. Actually some evidence suggests that weight loss after ACSs might in fact have a negative effect. We believe that given the current state of our knowledge, obesity paradox requires much more attention and deserves to be recognized in the guidelines…The available studies, together with previously published study data, permit the conclusion that fat tissue has several beneficial effects, for example in its action as an endocrine organ or as an aid in protecting against hip fracture. Obesity may carry benefit up to a certain degree, and it should be recognized that obesity is not necessarily associated with abnormal metabolic function.»

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‘Fitness’ and ‘Fatness’ Unrelated: Obesity not a Factor in Some People’s Health

Escrito por

Contrary to popular prognosis, Just because a person is fat does not mean their not fit.
According to a controversial study published online in the European Heart Journal, obesity does not necessarily determine a persons metabolic health and fitness.

Dr Francisco Ortega (PhD), a research associate affiliated to the Department of Physical Activity and Sport, University of Granada (Spain), and at the Department of Biosciences and Nutrition, Karolinska Institute in Stockholm, Sweden conducted a study under the direction of Professor Steven Blair, who is responsible for the long-running «Aerobics Center Longitudinal Study» (ACLS).

According to the study,43,265 clinically obese participants were recruited to the ACLS and studied between 1979 and 2003. They completed a detailed questionnaire, including information on their medical and lifestyle history, and they had a physical examination that included a treadmill test to assess cardio-respiratory fitness and measurements of height, weight, waist circumference, and their percentage of body fat. Blood pressure, cholesterol and fasting glucose levels were also measured. The study participants were followed until they died or until the end of 2003.
Results suggested that there are a subset of obese people who are metabolically healthy — they don’t suffer from conditions such as insulin resistance, diabetes and high cholesterol or blood pressure — and who have a higher level of fitness, as measured by how well the heart and lungs perform, than other obese people.
Obesity in itself did not have a detrimental effect on their health, and researchers say doctors should bear this in mind when considering what, if any, interventions are required, say the researchers.
«It is well known that obesity is linked to a large number of chronic diseases such as cardiovascular problems and cancer. However, there appears to be a sub-set of obese people who seem to be protected from obesity-related metabolic complications,» said Dr Ortega, first author of the study.
Many medical practitioners omit the fact that common obesity related health complications are in fact genetically determined. Persons diagnosed with diabetes, cardio-vascular diseases or even cancer are genetically predisposed to such issues (i.e. it runs in the family) and medical history should be the primary determinant of whether or not a person’s weight is a causal or sustaining factor in these issues.
The findings showed 46% of the obese participants were metabolically healthy with a 38% lower risk of death from any cause than their metabolically unhealthy obese peers. The risk of developing or dying from cardiovascular disease or cancer was reduced by between 30-50% for the metabolically healthy but obese people, and there were no significant differences observed between them and the metabolically healthy, normal weight participants.
«There are two major findings derived from our study. Firstly, a better cardio-respiratory fitness level should be considered from now on as a characteristic of this subset of metabolically healthy obese people. Secondly, once fitness is accounted for, our study shows for the first time that metabolically healthy but obese individuals have similar prognosis as metabolically healthy normal-weight individuals, and a better prognosis than their obese peers with an abnormal metabolic profile,» The authors write.
The only common ailment among obese women, regardless of their level of physical fitness is a delayed period. However, even normal weight women can have the same issue and both groups can be regulated with birth control.
It is well known that maintaining a healthy weight is one of the ways to avoid developing heart problems. However, as a result of another study which found that overweight and obese people had a much lower mortality rate than underweight or morbidly obese persons, the authors claim:
«We believe that no evidence exists that proves weight reduction in itself has a positive prognostic value after ACSs. Actually some evidence suggests that weight loss after ACSs might in fact have a negative effect. We believe that given the current state of our knowledge, obesity paradox requires much more attention and deserves to be recognized in the guidelines…The available studies, together with previously published study data, permit the conclusion that fat tissue has several beneficial effects, for example in its action as an endocrine organ or as an aid in protecting against hip fracture. Obesity may carry benefit up to a certain degree, and it should be recognized that obesity is not necessarily associated with abnormal metabolic function.»

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Can you really be both ‘fat and fit?’

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People «can be obese yet physically healthy and fit and at no greater risk of heart disease or cancer», according to BBC News.

This counterintuitive headline stems from a study that was assessing health outcomes for people who were obese but relatively fit, with only one or no risk factors for «metabolic syndrome». Metabolic syndrome is diagnosed when people have multiple risk factors, such as high blood pressure, that make them more prone to diabetes or cardiovascular disease (CVDs).

Researchers found that the «metabolic healthy» obese group were significantly less likely to develop a CVD or cancer, or die as a result, than people who were similarly obese but were judged to be «metabolic unhealthy». In fact the risks of CVDs and cancers in the «metabolic healthy but obese» group were broadly similar to people with a healthy weight.

However, the research should not be interpreted to mean that being obese is healthy. Waist circumference size is also a risk factor for CVDs, so ideally you should be aiming to have a circumference of less than 94cm (37in) if you’re a man and less than 80cm (31.5in) if you’re a woman.

The research actually tells us very little that is useful in how fitness levels can affect CVD and cancer risk and whether it is possible to be both «fat and fit».

The main implication of the research is that factors other than weight need to be taken in account when assessing these types of health risks.

Where did the story come from?
The study was carried out by researchers from the Karolinska Institute, Sweden, the University of Granada, Spain and the University of South Carolina, USA. The research was funded by the National Institutes of Health, the Spanish Ministry of Science and Innovation, the Swedish Heart-Lung Foundation and the Coca-Cola Company (the funding from Coca-Cola was given as an unrestricted grant; in other words «no strings attached»).

The study was published in the peer-reviewed European Heart Journal.

The media reflected the study findings accurately, but the newspaper headlines should not be interpreted to mean that being obese is healthy. A relevant health message that could have been added is that regular exercise can benefit you even if you remain overweight or obese despite your best efforts to lose weight.

What kind of research was this?
This was a cohort study aiming to look at the health of obese individuals who are metabolically healthy and without additional risk factors for CVDs. These were described by the researchers as people with «uncomplicated obesity».

The researchers said that there is uncertainty over the extent to which metabolic health in obese people can influence the risk of CVDs and overall mortality. This is what they aimed to examine.

They decided to examine two theories:

Metabolically healthy but obese individuals have a higher fitness level than obese individuals with metabolic abnormalities.
Metabolically healthy obese people have reduced risk of CVDs, cancer and mortality compared with obese individuals with metabolic abnormalities – the «theoretically unhealthiest group».
In this study, fitness (according to a treadmill test), obesity and metabolic risk factors all appear to have been measured at one point at the start of the study.

But it is difficult to tell how representative this one-off treadmill test is of the overall fitness level of an obese person, particularly as we don’t know how long the person has been obese for.

Measurements on obesity and metabolic health appear to be more reliable than those on fitness.

What did the research involve?
This was an analysis of the Aerobics Center Longitudinal Study (ACLS) which recruited predominantly white professional individuals between 1979 and 2003.

At the time of recruitment a number of assessements were carried out, including:

asking participants to complete a health questionnaire, including medical history and lifestyle habits (such as smoking and alcohol)
a physical examination (including measurement of BMI, body fat percentage and blood pressure) and blood tests taken for fasting blood sugar and lipids (triglycerides and high-density lipoprotein (HDL) «good» cholesterol)
They also performed an exercise treadmill test where they were asked to walk or jog slowly on a treadmill that increases its incline gradually. The test is then ended when the participants feel that they no longer have the stamina to continue (this type of test is known as the Balke treadmill protocol).

A person was defined as metabolically healthy if they met none or only one of the following criteria:

high blood pressure (≥130/85 mmHg)
high blood triglycerides (≥150 mg/dL)
low HDL «good» cholesterol (<40 and 50 mg/dL in men and women, respectively)
high fasting blood sugar level (≥100 mg/dL)
In addition, people with normal blood pressure or fasting blood sugar at the examination, but who reported a history of previously diagnosed high blood pressure or diabetes, were also classed as having these metabolic risk factors.

Participants were followed from recruitment to the end of 2003. Information on mortality came from the National Death Index. Data on non-fatal cardiovascular disease events came from the responses to health surveys in 1982, 1999 and 2004. There was said to be a 65% response rate across surveys.

Eligible participants had no history of cardiovascular disease or cancer at study start (baseline); had complete baseline data on body composition, metabolic risk factors and fitness and completed at least one year of follow-up for health and mortality outcomes.

What were the basic results?
A total 43,265 participants were included in the study (average age 44), a quarter of whom were women.

Of these:

5,649 were obese (13% of the cohort) according to the standard BMI definition (BMI ≥30 kg/m2)
12,829 (30%) were classed as obese when using body fat percentage criteria (≥25% for men or ≥30% women)
Measuring body fat as opposed to BMI is thought to be a more precise (if time-consuming) method of judging whether a person is overweight or obese.

Within the obese participants, 30% were «metabolically healthy» using BMI-based obesity criteria, and 46% were «metabolically healthy» using body fat percentage criteria.

The average follow-up period was said to be 14 years for mortality and eight years for non-fatal cardiovascular disease.

The main findings were:

«Metabolically healthy» obese participants had a better baseline fitness level on the treadmill test compared with «metabolically abnormal» obese participants (adjusting for age, sex, examination year, smoking and alcohol consumption, and when using either BMI or body fat percentage to define obesity). The difference was the same for men and women.
«Metabolically abnormal» obese participants had significantly increased risk of dying from any cause during follow-up compared with «metabolically healthy» obese participants (adjusting for confounders and using either BMI or body fat percentage to define obesity).
When looking at cardiovascular disease outcomes, «metabolically abnormal» obese participants only had increased risk of a fatal or non-fatal cardiovascular disease event compared with «metabolically healthy» obese participants when using body fat percentage to define obesity. There was no difference in risk when using standard BMI definitions.
«Metabolically healthy» obese participants had no difference in risk of dying from any cause, or of fatal or non-fatal cardiovascular disease events compared with «metabolically healthy» normal-weight or fat participants.

How did the researchers interpret the results?
The researchers concluded that metabolically healthy obese individuals have better fitness than their metabolically unhealthy obese counterparts. They also have a better prognosis in terms of mortality and disease risk.

Conclusion
This was an impressive study that benefited from a large sample size, its thorough assessments of medical health and fitness at the study’s start and long duration of follow-up.

It found that metabolic health is a predicator of overall health and fitness in obese people. This does not mean that being obese is healthy.

The study did have a number of limitations:

The one-off measure of fitness on the treadmill is hard to interpret as this was assessed at the same time as obesity and metabolic risk factors. We don’t know how representative this is of the person’s overall fitness in the longer term, which could have varied sharply over time. We also don’t know how long the person has been obese for, which makes it difficult to say much about the fitness of people with obesity, with or without metabolic risk factors.
There are possible issues with the follow-up for mortality and cardiovascular outcomes. The recruitment period was 1979 to 2003, and follow-up terminated in 2003. Although the researchers included only people who had been in the study for at least one year, the follow-up of outcomes may be quite short in some cases. Mortality was reliably monitored via the National Death Index, but non-fatal heart disease was reported only from health surveys in 1982, 1999 and 2004, to which there was only a 65% response rate. This means many cases may have been missed. This reduces the reliability of the measurement of the health outcomes described in the study, compared with an objective measure such as reviewing the medical records of participants.
The researchers also acknowledged that the criteria they used to define «metabolically healthy» and «metabolically unhealthy» may differ from other definitions that could have been used. As they said, they did not include information on waist circumference and did not have information on insulin resistance.
The study included predominantly white, middle-aged men, so it isn’t representative of all population groups.
Overall, the research plausibly suggests that people who are obese but have no other cardiovascular risk factors may be at lower risk of future diseases compared with obese people who have additional cardiovascular risk factors.

However, the research should not be interpreted to mean that being obese is healthy.

A more valid interpretation of these findings, as the authors said, is that it suggests that accurate assessments of body fat percentage and fitness may contribute to the overall assessment of an obese individual.

Descargar

Can you really be both ‘fat and fit?’

Escrito por

People «can be obese yet physically healthy and fit and at no greater risk of heart disease or cancer», according to BBC News.

This counterintuitive headline stems from a study that was assessing health outcomes for people who were obese but relatively fit, with only one or no risk factors for «metabolic syndrome». Metabolic syndrome is diagnosed when people have multiple risk factors, such as high blood pressure, that make them more prone to diabetes or cardiovascular disease (CVDs).

Researchers found that the «metabolic healthy» obese group were significantly less likely to develop a CVD or cancer, or die as a result, than people who were similarly obese but were judged to be «metabolic unhealthy». In fact the risks of CVDs and cancers in the «metabolic healthy but obese» group were broadly similar to people with a healthy weight.

However, the research should not be interpreted to mean that being obese is healthy. Waist circumference size is also a risk factor for CVDs, so ideally you should be aiming to have a circumference of less than 94cm (37in) if you’re a man and less than 80cm (31.5in) if you’re a woman.

The research actually tells us very little that is useful in how fitness levels can affect CVD and cancer risk and whether it is possible to be both «fat and fit».

The main implication of the research is that factors other than weight need to be taken in account when assessing these types of health risks.

Where did the story come from?
The study was carried out by researchers from the Karolinska Institute, Sweden, the University of Granada, Spain and the University of South Carolina, USA. The research was funded by the National Institutes of Health, the Spanish Ministry of Science and Innovation, the Swedish Heart-Lung Foundation and the Coca-Cola Company (the funding from Coca-Cola was given as an unrestricted grant; in other words «no strings attached»).

The study was published in the peer-reviewed European Heart Journal.

The media reflected the study findings accurately, but the newspaper headlines should not be interpreted to mean that being obese is healthy. A relevant health message that could have been added is that regular exercise can benefit you even if you remain overweight or obese despite your best efforts to lose weight.

What kind of research was this?
This was a cohort study aiming to look at the health of obese individuals who are metabolically healthy and without additional risk factors for CVDs. These were described by the researchers as people with «uncomplicated obesity».

The researchers said that there is uncertainty over the extent to which metabolic health in obese people can influence the risk of CVDs and overall mortality. This is what they aimed to examine.

They decided to examine two theories:

Metabolically healthy but obese individuals have a higher fitness level than obese individuals with metabolic abnormalities.
Metabolically healthy obese people have reduced risk of CVDs, cancer and mortality compared with obese individuals with metabolic abnormalities – the «theoretically unhealthiest group».
In this study, fitness (according to a treadmill test), obesity and metabolic risk factors all appear to have been measured at one point at the start of the study.

But it is difficult to tell how representative this one-off treadmill test is of the overall fitness level of an obese person, particularly as we don’t know how long the person has been obese for.

Measurements on obesity and metabolic health appear to be more reliable than those on fitness.

What did the research involve?
This was an analysis of the Aerobics Center Longitudinal Study (ACLS) which recruited predominantly white professional individuals between 1979 and 2003.

At the time of recruitment a number of assessements were carried out, including:

asking participants to complete a health questionnaire, including medical history and lifestyle habits (such as smoking and alcohol)
a physical examination (including measurement of BMI, body fat percentage and blood pressure) and blood tests taken for fasting blood sugar and lipids (triglycerides and high-density lipoprotein (HDL) «good» cholesterol)
They also performed an exercise treadmill test where they were asked to walk or jog slowly on a treadmill that increases its incline gradually. The test is then ended when the participants feel that they no longer have the stamina to continue (this type of test is known as the Balke treadmill protocol).

A person was defined as metabolically healthy if they met none or only one of the following criteria:

high blood pressure (≥130/85 mmHg)
high blood triglycerides (≥150 mg/dL)
low HDL «good» cholesterol (<40 and 50 mg/dL in men and women, respectively)
high fasting blood sugar level (≥100 mg/dL)
In addition, people with normal blood pressure or fasting blood sugar at the examination, but who reported a history of previously diagnosed high blood pressure or diabetes, were also classed as having these metabolic risk factors.

Participants were followed from recruitment to the end of 2003. Information on mortality came from the National Death Index. Data on non-fatal cardiovascular disease events came from the responses to health surveys in 1982, 1999 and 2004. There was said to be a 65% response rate across surveys.

Eligible participants had no history of cardiovascular disease or cancer at study start (baseline); had complete baseline data on body composition, metabolic risk factors and fitness and completed at least one year of follow-up for health and mortality outcomes.

What were the basic results?
A total 43,265 participants were included in the study (average age 44), a quarter of whom were women.

Of these:

5,649 were obese (13% of the cohort) according to the standard BMI definition (BMI ≥30 kg/m2)
12,829 (30%) were classed as obese when using body fat percentage criteria (≥25% for men or ≥30% women)
Measuring body fat as opposed to BMI is thought to be a more precise (if time-consuming) method of judging whether a person is overweight or obese.

Within the obese participants, 30% were «metabolically healthy» using BMI-based obesity criteria, and 46% were «metabolically healthy» using body fat percentage criteria.

The average follow-up period was said to be 14 years for mortality and eight years for non-fatal cardiovascular disease.

The main findings were:

«Metabolically healthy» obese participants had a better baseline fitness level on the treadmill test compared with «metabolically abnormal» obese participants (adjusting for age, sex, examination year, smoking and alcohol consumption, and when using either BMI or body fat percentage to define obesity). The difference was the same for men and women.
«Metabolically abnormal» obese participants had significantly increased risk of dying from any cause during follow-up compared with «metabolically healthy» obese participants (adjusting for confounders and using either BMI or body fat percentage to define obesity).
When looking at cardiovascular disease outcomes, «metabolically abnormal» obese participants only had increased risk of a fatal or non-fatal cardiovascular disease event compared with «metabolically healthy» obese participants when using body fat percentage to define obesity. There was no difference in risk when using standard BMI definitions.
«Metabolically healthy» obese participants had no difference in risk of dying from any cause, or of fatal or non-fatal cardiovascular disease events compared with «metabolically healthy» normal-weight or fat participants.

How did the researchers interpret the results?
The researchers concluded that metabolically healthy obese individuals have better fitness than their metabolically unhealthy obese counterparts. They also have a better prognosis in terms of mortality and disease risk.

Conclusion
This was an impressive study that benefited from a large sample size, its thorough assessments of medical health and fitness at the study’s start and long duration of follow-up.

It found that metabolic health is a predicator of overall health and fitness in obese people. This does not mean that being obese is healthy.

The study did have a number of limitations:

The one-off measure of fitness on the treadmill is hard to interpret as this was assessed at the same time as obesity and metabolic risk factors. We don’t know how representative this is of the person’s overall fitness in the longer term, which could have varied sharply over time. We also don’t know how long the person has been obese for, which makes it difficult to say much about the fitness of people with obesity, with or without metabolic risk factors.
There are possible issues with the follow-up for mortality and cardiovascular outcomes. The recruitment period was 1979 to 2003, and follow-up terminated in 2003. Although the researchers included only people who had been in the study for at least one year, the follow-up of outcomes may be quite short in some cases. Mortality was reliably monitored via the National Death Index, but non-fatal heart disease was reported only from health surveys in 1982, 1999 and 2004, to which there was only a 65% response rate. This means many cases may have been missed. This reduces the reliability of the measurement of the health outcomes described in the study, compared with an objective measure such as reviewing the medical records of participants.
The researchers also acknowledged that the criteria they used to define «metabolically healthy» and «metabolically unhealthy» may differ from other definitions that could have been used. As they said, they did not include information on waist circumference and did not have information on insulin resistance.
The study included predominantly white, middle-aged men, so it isn’t representative of all population groups.
Overall, the research plausibly suggests that people who are obese but have no other cardiovascular risk factors may be at lower risk of future diseases compared with obese people who have additional cardiovascular risk factors.

However, the research should not be interpreted to mean that being obese is healthy.

A more valid interpretation of these findings, as the authors said, is that it suggests that accurate assessments of body fat percentage and fitness may contribute to the overall assessment of an obese individual.

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‘Obesity paradox’: underweight more at risk

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Some obese people are as healthy and fit as those of normal weight – and carry no greater risk of developing heart disease or cancer.

This is one of the findings, published in the European Heart Journal on Tuesday, of the largest study ever to have investigated this subject.

And a second study describes something called the «obesity paradox»: once people have developed heart disease, they are less likely to die if they are overweight or obese, while the underweight or normal weight patients have an increased risk of dying.

In the first study, the researchers from the University of Granada, the Karolina Institute in Sweden and the University of South Carolina in the US found that there is a subset of obese people who are metabolically healthy: they do not suffer from diabetes, high cholesterol or high blood pressure.

Lead author Francisco Ortega said in a statement released by EurekAlert! that it was well known that obesity was linked to a large number of chronic diseases like heart disease and cancer.

«However, there appears to be a subset of obese people who seem to be protected from obesity-related metabolic complications,» he said.

The research looked at 43 265 people, who were recruited from the Aerobics Centre Longitudinal Study in the US between 1979 and 2003.

The study showed that the difference between this healthy obese subset and other obese individuals was that the subset had better levels of cardio-vascular fitness – measured by how well their hearts and lungs performed – which was largely from getting more exercise.

Ortega said their study suggested that those obese people who were metabolically healthy were also those who were fitter than the other obese people.

«We believe getting more exercise positively influences major body systems and organs and contributes to making someone metabolically healthier, including obese people,» Ortega said.

He said the study showed for the first time that metabolically healthy obese people had the same prognosis as those of normal weight.

The second study, about the obesity paradox, analysed data between 2003 and 2008 from 64 000 Swedish patients who had heart disease.

The researchers discovered that the heart patients who were underweight had the greatest risk of dying – double that of normal-weight patients.

Those patients with the lowest risk of death were the overweight and obese patients.

The researchers say it is well known that maintaining a healthy weight is one way to avoid developing heart problems. But once overweight or obese people had developed heart disease, there was no evidence that proved their losing weight would help their heart problems.

Oskar Angeras from the University of Gothenburg said: «Actually, some evidence suggests that weight loss after acute coronary syndromes might in fact have a negative effect.» –

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‘Obesity paradox’: underweight more at risk

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Some obese people are as healthy and fit as those of normal weight – and carry no greater risk of developing heart disease or cancer.

This is one of the findings, published in the European Heart Journal on Tuesday, of the largest study ever to have investigated this subject.

And a second study describes something called the «obesity paradox»: once people have developed heart disease, they are less likely to die if they are overweight or obese, while the underweight or normal weight patients have an increased risk of dying.

In the first study, the researchers from the University of Granada, the Karolina Institute in Sweden and the University of South Carolina in the US found that there is a subset of obese people who are metabolically healthy: they do not suffer from diabetes, high cholesterol or high blood pressure.

Lead author Francisco Ortega said in a statement released by EurekAlert! that it was well known that obesity was linked to a large number of chronic diseases like heart disease and cancer.

«However, there appears to be a subset of obese people who seem to be protected from obesity-related metabolic complications,» he said.

The research looked at 43 265 people, who were recruited from the Aerobics Centre Longitudinal Study in the US between 1979 and 2003.

The study showed that the difference between this healthy obese subset and other obese individuals was that the subset had better levels of cardio-vascular fitness – measured by how well their hearts and lungs performed – which was largely from getting more exercise.

Ortega said their study suggested that those obese people who were metabolically healthy were also those who were fitter than the other obese people.

«We believe getting more exercise positively influences major body systems and organs and contributes to making someone metabolically healthier, including obese people,» Ortega said.

He said the study showed for the first time that metabolically healthy obese people had the same prognosis as those of normal weight.

The second study, about the obesity paradox, analysed data between 2003 and 2008 from 64 000 Swedish patients who had heart disease.

The researchers discovered that the heart patients who were underweight had the greatest risk of dying – double that of normal-weight patients.

Those patients with the lowest risk of death were the overweight and obese patients.

The researchers say it is well known that maintaining a healthy weight is one way to avoid developing heart problems. But once overweight or obese people had developed heart disease, there was no evidence that proved their losing weight would help their heart problems.

Oskar Angeras from the University of Gothenburg said: «Actually, some evidence suggests that weight loss after acute coronary syndromes might in fact have a negative effect.» –

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Fat people can be healthy: study

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Nearly half of overweight people per se are physically fit and healthy and at no greater risk of heart disease or cancer, than their slim peers, researchers claim.

According to experts, the key is being «metabolically fit», meaning no high blood pressure, cholesterol or raised blood sugar, and exercising.

Looking at data from over 43,000 US people they found that being overweight per se did not pose a big health risk, the BBC News reported.

More than a third of the participants were obese in the study conducted at the University of South Carolina.

Of these 18,500, half were assessed as metabolically healthy after a physical examination and lab tests.

This subset of metabolically healthy obese people who did not suffer from conditions such as diabetes, high cholesterol or high blood pressure, were generally fitter and exercised more than the other obese people.

Their risk of developing or dying from cardiovascular disease or cancer was identical to people of ideal weight and was half that of «metabolically less fit» obese people.

Lead researcher Francisco Ortega, who currently works at the University of Granada in Spain, said the findings show that getting more exercise can keep you healthier, even if you still carry a bit of extra weight.

«This research highlights once again the important role of physical fitness as a health marker,» Ortega said.

Most of the men and women in the study came from a similar background, meaning the results may not apply to everyone.

They were mostly Caucasian, well educated, and worked in executive or professional positions.

«In the majority of cases, obesity is an undeniable risk factor for developing coronary heart disease. However, these studies remind us that it is not always your weight that’s important, but where you carry fat and also how it affects your health and fitness,» Amy Thompson, of the British Heart Foundation, said.

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Fat people can be healthy: study

Escrito por

Nearly half of overweight people per se are physically fit and healthy and at no greater risk of heart disease or cancer, than their slim peers, researchers claim.

According to experts, the key is being «metabolically fit», meaning no high blood pressure, cholesterol or raised blood sugar, and exercising.

Looking at data from over 43,000 US people they found that being overweight per se did not pose a big health risk, the BBC News reported.

More than a third of the participants were obese in the study conducted at the University of South Carolina.

Of these 18,500, half were assessed as metabolically healthy after a physical examination and lab tests.

This subset of metabolically healthy obese people who did not suffer from conditions such as diabetes, high cholesterol or high blood pressure, were generally fitter and exercised more than the other obese people.

Their risk of developing or dying from cardiovascular disease or cancer was identical to people of ideal weight and was half that of «metabolically less fit» obese people.

Lead researcher Francisco Ortega, who currently works at the University of Granada in Spain, said the findings show that getting more exercise can keep you healthier, even if you still carry a bit of extra weight.

«This research highlights once again the important role of physical fitness as a health marker,» Ortega said.

Most of the men and women in the study came from a similar background, meaning the results may not apply to everyone.

They were mostly Caucasian, well educated, and worked in executive or professional positions.

«In the majority of cases, obesity is an undeniable risk factor for developing coronary heart disease. However, these studies remind us that it is not always your weight that’s important, but where you carry fat and also how it affects your health and fitness,» Amy Thompson, of the British Heart Foundation, said.

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