Bacon, sausage, and ham -- some of the most beloved foodstuffs on the planet --are once again being singled out as key culprits driving the association between meat consumption and the world's most common diseases.
In one of the largest studies to address this question, high consumption of processed meat by middle-aged adults was associated with a near doubling of the risk of all-cause mortality, compared with low consumption, over a mean of 12 years. Risk of cardiovascular death, after rigorous modeling, was increased by more than 70% among people eating more than 160 g/day, as compared with those eating 10 to 19.9 g/day. Risk of cancer deaths was also 43% higher among the highest consumers of processed meats.
"The clinical message, in our opinion, is that it's okay to eat some meat, but to limit consumption of processed meat: not every day and not in high amounts," lead author Dr Sabine Rohrmann (University of Zurich, Switzerland) told heartwire in an email.
EPIC Data
The new data come from the European Prospective Investigation into Cancer and Nutrition (EPIC) study, involving 10 countries and almost half a million men and women. It was published online today inBMC Medicine.
Of note, say the authors, while a signal of increased mortality was seen among the highest consumers of red meat in general, the risk for red meat was much lower that that of processed meats and lost statistical significance after correction for measurement error. With the same adjustments and corrections, high processed-meat consumption was associated with an 18% greater risk of all-cause mortality.
As the authors point out, processed meats tend to contain more saturated fat than unprocessed meat (where the fat is often trimmed off), as well as more cholesterol and additives, often as part of the smoking or curing process. Some of these are believed to be carcinogenic or precursors to carcinogenic processes. "Another factor is the content of salt in processed-meat products, which is linked to hypertension, which is a CVD risk factor," Rohrmann told heartwire . "Heme iron is another mechanism, which links meat consumption to CVD risk, but that's not limited to processed meat."
Rohrmann and colleagues also point out that high consumption of processed meat typically went hand in hand with other unhealthy behaviors, including smoking, low physical-activity levels, and low consumption of fruits and vegetables.
"Overall, we estimate that 3% of premature deaths each year could be prevented if people ate less than 20 g of processed meat per day," Rohrmann commented in a press statement.
What about red meat?
Other studies have singled out processed meats as particularly hazardous to health. US analyses of meat consumption and mortality, drawing on data from two large, long-running US studies, have also documented the link between meat consumption and CVD and cancer deaths, but the stronger association seen with processed meats in this European cohort is somewhat at odds with the American data.
"Although we did not find a statistically significant association between unprocessed red-meat consumption and mortality in our studies, the two US studies did," Rohrmann said. "Therefore, we would not say that there is definitely no association [between red-meat consumption and CVD]. What I think our studies show is that it's okay to eat a moderate amount of meat--300 to 600 g per week as recommended by many nutrition societies--for intake of some important minerals and vitamins; however, a balanced vegetarian diet is, of course, okay as well."
Source: http://www.medscape.com/viewarticle/780412?nlid=29037_1301&src=wnl_edit_dail
Welcome to my collection of health articles. Most of them contain little nuggets of health wisdom that we can easily apply to our daily lives. As you can gather, I've been consuming all sorts of supplements over the years, most of them from iherb. They deliver on time (DHL), and prices are good. If you're a first-time buyer, use my code 'pot089' to enjoy up to $10 off.
Saturday, 9 March 2013
Friday, 1 March 2013
Acne: Bad and good bacteria identified
A genomic approach to comparing acne-ridden skin with clear human skin has revealed a bacterial strain that may protect against the disease. The work was published online February 28 in the Journal of Investigative Dermatology by Sorel Fitz-Gibbon, PhD, from the Department of Molecular and Medical Pharmacology, Crump Institute for Molecular Imaging, David Geffen School of Medicine, University of California, Los Angeles, and colleagues.
Four of 5 people in the United States develop acne at some point. Although dermatologists no longer blame blemishes on too much chocolate or fatty foods, commonly prescribed acne drugs such as benzoyl peroxide, antibiotics, and isotretinoin (Accutane, Roche) have been used for decades, although they are not ideal. Antibiotics are usually ineffective in severe cases, and isotretinoin both has adverse effects and is teratogenic.
Propionibacterium acnes is a dominant skin commensal that colonizes pilosebaceous units, in which certain strains are hypothesized to stimulate development of acne vulgaris. The population sizes of the bacteria are similar among individuals, but the proportions of different strains vary between people prone to acne and people with clear skin. Similar to Staphylococcus aureus, only certain strains of the bacteria are pathogenic.
The researchers sequenced bacterial genomes to better define the genetic compositions of the P acne component of the skin microbiome in acne-marked vs healthy skin. The strategy revealed "a previously unreported portrait of the microbiota of pilosebaceous units at the bacterial strain level," the researchers write.
Dr. Fitz-Gibbon and colleagues applied over-the-counter pore-cleansing strips to the noses of 49 people with acne and 52 participants with clear skin, sampling P acnes in whiteheads or blackheads. The investigators typed bacterial strains according to 16S ribosomal DNA sequences (ribotypes), assigning each strain an acne index based on prevalence among patients with acne. This approach identified 11,009 ribotypes, but only a few were abundant in either patient group.
Genome sequencing was the next step. Team members from Washington University in St. Louis, Missouri, sequenced the genomes of 66 previously unreported P acnes strains from the samples and compared 71 bacterial genome types overall. Author Shuta Tomida, PhD, also from the Department of Molecular and Medical Pharmacology, Crump Institute for Molecular Imaging, David Geffen School of Medicine, identified DNA differences among the strains.
Beneficial Bacteria
Three genomically identified strains are of potential clinical significance. Two strains were discovered in 1 of 5 volunteers with acne, but rarely in clear-skinned people. Conversely, a third bacterial strain appeared to be common in healthy skin yet was rare in skin with acne, suggesting a protective role.
The findings may have practical applications, the authors write, such as the development of a probiotic topical preparation to favor the protective bacterial strain or drugs to selectively target acne-related bacteria. A simple skin test might predict whether a person has an increased risk of developing aggressive acne.
Further studies might address identifying host factors that contribute to acne and matching microbiome subtypes with clinical subtypes of acne, such as cystic, pustular, or inflammatory acne.
"By combining a metagenomic study of the skin microbiome and genome sequencing of this major skin commensal, this study provides insight into potential bacterial genetic determinants in acne pathogenesis and emphasizes the importance of strain-level analysis of the human microbiome to understand the role of commensals in health and disease," the researchers conclude.
Source: http://www.medscape.com/viewarticle/780020?nlid=28944_1301&src=wnl_edit_dail
Four of 5 people in the United States develop acne at some point. Although dermatologists no longer blame blemishes on too much chocolate or fatty foods, commonly prescribed acne drugs such as benzoyl peroxide, antibiotics, and isotretinoin (Accutane, Roche) have been used for decades, although they are not ideal. Antibiotics are usually ineffective in severe cases, and isotretinoin both has adverse effects and is teratogenic.
Propionibacterium acnes is a dominant skin commensal that colonizes pilosebaceous units, in which certain strains are hypothesized to stimulate development of acne vulgaris. The population sizes of the bacteria are similar among individuals, but the proportions of different strains vary between people prone to acne and people with clear skin. Similar to Staphylococcus aureus, only certain strains of the bacteria are pathogenic.
The researchers sequenced bacterial genomes to better define the genetic compositions of the P acne component of the skin microbiome in acne-marked vs healthy skin. The strategy revealed "a previously unreported portrait of the microbiota of pilosebaceous units at the bacterial strain level," the researchers write.
Dr. Fitz-Gibbon and colleagues applied over-the-counter pore-cleansing strips to the noses of 49 people with acne and 52 participants with clear skin, sampling P acnes in whiteheads or blackheads. The investigators typed bacterial strains according to 16S ribosomal DNA sequences (ribotypes), assigning each strain an acne index based on prevalence among patients with acne. This approach identified 11,009 ribotypes, but only a few were abundant in either patient group.
Genome sequencing was the next step. Team members from Washington University in St. Louis, Missouri, sequenced the genomes of 66 previously unreported P acnes strains from the samples and compared 71 bacterial genome types overall. Author Shuta Tomida, PhD, also from the Department of Molecular and Medical Pharmacology, Crump Institute for Molecular Imaging, David Geffen School of Medicine, identified DNA differences among the strains.
Beneficial Bacteria
Three genomically identified strains are of potential clinical significance. Two strains were discovered in 1 of 5 volunteers with acne, but rarely in clear-skinned people. Conversely, a third bacterial strain appeared to be common in healthy skin yet was rare in skin with acne, suggesting a protective role.
The findings may have practical applications, the authors write, such as the development of a probiotic topical preparation to favor the protective bacterial strain or drugs to selectively target acne-related bacteria. A simple skin test might predict whether a person has an increased risk of developing aggressive acne.
Further studies might address identifying host factors that contribute to acne and matching microbiome subtypes with clinical subtypes of acne, such as cystic, pustular, or inflammatory acne.
"By combining a metagenomic study of the skin microbiome and genome sequencing of this major skin commensal, this study provides insight into potential bacterial genetic determinants in acne pathogenesis and emphasizes the importance of strain-level analysis of the human microbiome to understand the role of commensals in health and disease," the researchers conclude.
Source: http://www.medscape.com/viewarticle/780020?nlid=28944_1301&src=wnl_edit_dail
Global rise in diabetes linked to increase in dietary sugar
The increasing availability of sugary food and drink — independent of excess calories, excess weight, or a sedentary lifestyle — explains part of the rise in cases of type 2 diabetes worldwide, suggests a new study published online February 27 in PLoS ONE.
The authors, led by Sanjay Basu, MD, from the Department of Medicine, Stanford University, Palo Alto, California, examined a decade of cross-sectional data from 175 countries. They note that most of the worldwide rise in diabetes is thought to be type 2, linked to the metabolic syndrome, a cluster of factors including dyslipidemia, hypertension, and insulin resistance.
They report that for each added 150 calories of sugar available per person per day — equivalent to one 12-oz can of soda — the prevalence of type 2 diabetes increased by about 1% (P < .001), after they controlled for factors such as food types, total calories, overweight and obesity rates, aging, urbanization, income, and time.
Sugar Alone Explains 25% of Increase in Diabetes
It is important to identify risk factors for type 2 diabetes, since nearly 1 in 10 adults worldwide has the condition, and the rates are increasing. "If obesity is a primary driver of diabetes, then measures to reduce calorie consumption and increase physical activity should be prioritized," Basu and colleagues write. "However, if added sugar consumption is a primary driver, then public health policies to reduce sugar consumption warrant investigation as diabetes-prevention proposals — especially for developing countries, where diabetes rates are rising dramatically, irrespective of obesity."
They give examples of several countries with high diabetes prevalence rates but low obesity rates, including the Philippines, Romania, France, Bangladesh, and Georgia.
To determine whether sugar in a country's food supply predicts subsequent spikes in diabetes rates, the researchers used a regression model to correlate the prevalence of diabetes from 2000 to 2010 in adults aged 20 to 79 living in 175 countries with the availability of sugar in a country's food supply.
They found that during this decade, the prevalence of worldwide diabetes rose by about 27%, with one quarter of this increase explained by an increase in the availability of sugary foods. No other food category had any significant effect on diabetes prevalence.
Rates of diabetes increased in a dose-dependent manner the longer a population was exposed to excess sugar and the greater the amount of available sugar in the food supply. Each extra year of living where sugary foods were widely available was linked with an increase in diabetes prevalence of 0.053% (P < .05).
The reverse was also true. Following periods of scarce sugar (typically due to changes in trade agreements), the prevalence of diabetes decreased by 0.074% (P< .05), after correction for confounding variables.
Although their findings were robust, the study was not designed to establish a causal link between sugar intake and subsequent diabetes diagnosis, the authors admit. Prospective longitudinal cohort studies in international settings, which are now under way, should shed more light on this link.
The authors, led by Sanjay Basu, MD, from the Department of Medicine, Stanford University, Palo Alto, California, examined a decade of cross-sectional data from 175 countries. They note that most of the worldwide rise in diabetes is thought to be type 2, linked to the metabolic syndrome, a cluster of factors including dyslipidemia, hypertension, and insulin resistance.
They report that for each added 150 calories of sugar available per person per day — equivalent to one 12-oz can of soda — the prevalence of type 2 diabetes increased by about 1% (P < .001), after they controlled for factors such as food types, total calories, overweight and obesity rates, aging, urbanization, income, and time.
Sugar Alone Explains 25% of Increase in Diabetes
It is important to identify risk factors for type 2 diabetes, since nearly 1 in 10 adults worldwide has the condition, and the rates are increasing. "If obesity is a primary driver of diabetes, then measures to reduce calorie consumption and increase physical activity should be prioritized," Basu and colleagues write. "However, if added sugar consumption is a primary driver, then public health policies to reduce sugar consumption warrant investigation as diabetes-prevention proposals — especially for developing countries, where diabetes rates are rising dramatically, irrespective of obesity."
They give examples of several countries with high diabetes prevalence rates but low obesity rates, including the Philippines, Romania, France, Bangladesh, and Georgia.
To determine whether sugar in a country's food supply predicts subsequent spikes in diabetes rates, the researchers used a regression model to correlate the prevalence of diabetes from 2000 to 2010 in adults aged 20 to 79 living in 175 countries with the availability of sugar in a country's food supply.
They found that during this decade, the prevalence of worldwide diabetes rose by about 27%, with one quarter of this increase explained by an increase in the availability of sugary foods. No other food category had any significant effect on diabetes prevalence.
Rates of diabetes increased in a dose-dependent manner the longer a population was exposed to excess sugar and the greater the amount of available sugar in the food supply. Each extra year of living where sugary foods were widely available was linked with an increase in diabetes prevalence of 0.053% (P < .05).
The reverse was also true. Following periods of scarce sugar (typically due to changes in trade agreements), the prevalence of diabetes decreased by 0.074% (P< .05), after correction for confounding variables.
Although their findings were robust, the study was not designed to establish a causal link between sugar intake and subsequent diabetes diagnosis, the authors admit. Prospective longitudinal cohort studies in international settings, which are now under way, should shed more light on this link.
Source: http://www.medscape.com/viewarticle/779985?nlid=28944_1301&src=wnl_edit_dail&pa=PCYXhnapQ2wZF1d7JGcwb4Ym85nElZ8ukcKRvE7ifDe0gl7tve%2FFWz1pQS47LFuU43mU9jD%2B1DtnxY47OmyybA%3D%3D
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