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A plant-based diet (eating lots of plant foods - fruits, vegetables, whole grains, legumes, seeds and nuts) once again shows health benefits in a new study - here a lower incidence of type 2 diabetes. But what kind of plant-based foods one eats is important: consumption of a plant-based diet that emphasized healthy plant foods was associated with a larger decrease (34%) in diabetes risk, while consumption of a plant-based diet high in less healthy plant foods (soda, fruit juices, sweets/desserts, refined grains) was associated with a 16% increased diabetes risk. From Medical Xpress:

Healthy plant-based diet linked with substantially lower type 2 diabetes risk

Consuming a plant-based diet—especially one rich in high-quality plant foods such as whole grains, fruits, vegetables, nuts, and legumes—is linked with substantially lower risk of developing type 2 diabetes, according to a new study from Harvard T.H. Chan School of Public Health.

While previous studies have found links between vegetarian diets and improved health outcomes, including reduced risk of type 2 diabetes, this new study is the first to make distinctions between healthy plant-based diets and less healthy ones that include things like sweetened foods and beverages, which may be detrimental for health. The study also considered the effect of including some animal foods in the diet.

The researchers followed more than 200,000 male and female health professionals across the U.S. for more than 20 years who had regularly filled out questionnaires on their diet, lifestyle, medical history, and new disease diagnoses as part of three large long-term studies. The researchers evaluated participants' diets using a plant-based diet index in which they assigned plant-derived foods higher scores and animal-derived foods lower scores.

The study found that high adherence to a plant-based diet that was low in animal foods was associated with a 20% reduced risk of type 2 diabetes compared with low adherence to such a diet. Eating a healthy version of a plant-based diet was linked with a 34% lower diabetes risk, while a less healthy version—including foods such as refined grains, potatoes, and sugar-sweetened beverages—was linked with a 16% increased risk. Even modestly lowering animal food consumption—for example, from 5-6 servings per day to about 4 servings per day—was linked with lower diabetes incidence, the study found.

The researchers suggested that healthful plant-based diets could be lowering type 2 diabetes risk because such diets are high in fiber, antioxidants, unsaturated fatty acids, and micronutrients such as magnesium, and are low in saturated fat. Healthy plant foods may also be contributing to a healthy gut microbiome, the authors said.

A recent editorial in the journal Cardiology calls exercise the "magic bullet" in preventing all sorts of diseases, including cardiovascular disease and diabetes.

From Science Daily: Regular physical activity is 'magic bullet' for pandemics of obesity, cardiovascular disease

In an editorial published in the current issue of Cardiology, professors from the Charles E. Schmidt College of Medicine at Florida Atlantic University have evaluated the totality of evidence and conclude that regular physical activity bears the closest resemblance to a "magic bullet" to combat the worldwide epidemic of obesity and cardiovascular disease.

The statistics on regular physical activity in the United States are bleak; only about 20 percent of Americans (23 percent of men and 18 percent of women) engage in recommended levels of regular physical activity and about 64 percent never do any physical activity. In Europe, the statistics are not much better with only 33 percent who engage in physical activity with some regularity, while 42 percent never do any physical activity.

The authors also point out that physical activity confers important beneficial effects beyond body weight and include blood pressure, cholesterol, triglyceride, diabetes, heart attacks, strokes, colon cancer and possibly even breast and prostate cancers as well as arthritis, mood, energy, sleep and sex life.

Starting in their 30s, Americans and many Europeans tend to gain between 1 and 3 pounds of body weight per year, and by 55, many are between 30 and 50 pounds overweight....The authors note that brisk walking for only 20 minutes a day burns about 700 calories a week, results in a 30 to 40 percent reduced risk of coronary heart disease, and can be performed even by the elderly. They stress that regular physical activity also should include resistance exercise such as lifting weights, which can even be safely performed in the elderly and in patients with heart failure.

Get out there and start getting active NOW - the earlier you start in life, the better for your brain decades later. All physical activity or exercise is good, including regular walks. From Medical Xpress:

Regular exercise protects against cognitive decline in later years

Regular exercise in middle age is the best lifestyle change a person can make to prevent cognitive decline in the later years, a landmark 20-year study has found.

University of Melbourne researchers followed 387 Australian women from the Women's Healthy Ageing Project for two decades. The women were aged 45 to 55-years-old when the study began in 1992. The research team made note of their lifestyle factors, including exercise and diet, education, marital and employment status, number of children, mood, physical activity and smoking....They were also asked to learn a list of 10 unrelated words and attempt to recall them half an hour later, known as an Episodic Verbal Memory test.

When measuring the amount of memory loss over 20 years, frequent physical activity, normal blood pressure and high good cholesterol were all strongly associated with better recall of the words. Study author Associate Professor Cassandra Szoeke, who leads the Women's Healthy Ageing Project, said once dementia occurs, it is irreversible. "In our study more weekly exercise was associated with better memory." 

"We now know that brain changes associated with dementia take 20 to 30 years to develop," Associate Professor Szoeke said. "The evolution of cognitive decline is slow and steady, so we needed to study people over a long time period. We used a verbal memory test because that's one of the first things to decline when you develop Alzheimer's Disease."
Regular exercise of any type, from walking the dog to mountain climbing, emerged as the number one protective factor against memory loss. Asoc Prof Szoeke said that the best effects came from cumulative exercise, that is, how much you do and how often over the course of your life.  (Original study)

Obesity rates in the US are high! Obesity rates in the US were 35% among men and 40.4% in women in 2013-2014, and extreme obesity (class 3) rates were 5.5% for men and 9.9% for women. Obesity is defined as a body mass index (BMI) 30 or greater (≥30), and extreme obesity or class 3 obesity is a body mass index of 40 or greater (BMI ≥40).

A second study analyzed data from 186 countries and found that global obesity numbers have shot up from 105 million people in 1975 to 641 million in 2014. The senior author Dr. Majid Ezzati of the study said: "Over the past 40 years, we have changed from a world in which underweight prevalence was more than double that of obesity, to one in which more people are obese than underweight."

From Science Daily: Prevalence of obesity in U.S. increases among women, but not men

The prevalence of obesity in 2013- 2014 was 35 percent among men and 40 percent among women, and between 2005 and 2014, there was an increase in prevalence among women, but not men, according to a study appearing in the June 7 issue of JAMA. Between 1980 and 2000, the prevalence of obesity increased significantly among adult men and women in the United States...The analysis included data from 2,638 adult men (average age, 47 years) and 2,817 women (average age, 48 years) from the most recent 2 years (2013-2014) of NHANES and data from 21,013 participants in previous NHANES surveys from 2005 through 2012.

For the years 2013-2014, the overall age-adjusted prevalence of obesity (body mass index [BMI] 30 or greater) was 38 percent; among men, it was 35 percent; and among women, it was 40 percent. The corresponding prevalence of class 3 (BMI 40 or greater) obesity overall was 7.7 percent; among men, it was 5.5 percent; and among women, it was 9.9 percent. 

The authors write that although there has been considerable speculation about the causes of the increases in obesity prevalence, data are lacking to show the causes of these trends, and there are few data to indicate reasons that these trends might accelerate, stop, or slow. "Other studies are needed to determine the reasons for these trends." 

From Medscape: Obesity Now More Common Than Underweight Worldwide

Global obesity numbers have shot up from 105 million people in 1975 to 641 million in 2014, according to the most comprehensive body mass index (BMI) trend analysis to date. Researchers estimate that the age-corrected proportion of men who were obese climbed from 3.2% to 10.8% in that time and the rate among women more than doubled, going from 6.4% to 14.9%. During the same 40-year period, the proportion of men who were underweight globally fell from 13.8% to 8.8% and among women it declined from 14.6% to 9.7%.

Underweight numbers were highest in South Asia in 2014 at 23.4% (95% CI, 17.8%–29.2%) in men and 24% (95% CI, 18.9%–29.3%) in women. Underweight prevalence also stood at more than 12% in women and more than 15% in men in Central and East Africa in 2014, despite some reductions over the 4 decades....Almost half of the world's underweight men (46.2%) and women (41.6%) live in India, the study found.

Polynesia and Micronesia had the highest average BMI in the world. More than 38% of men and over half of women are obese there. The study finds that almost 20% of the world's obese adults (118 million) live in six high-income countries—Australia, Canada, Ireland, New Zealand, the United Kingdom, and the United States. More than a quarter (27.1% or 50 million) of the world's severely obese people also live in these countries. More than one in four severely obese men (27.8%) and 18.3% of severely obese women in the world live in the United States.

Surprising results (to me at least) from research comparing various diets and incidence of several cancers in 11,082 individuals in the Netherlands over a 20 year period. I expected the daily meat eaters to have higher rates of the 3 cancers studied, but no....

According to this study, looks like frequent meat consumption is OK when looking at lung, postmenopausal breast, and prostate cancer. Meat consumption did not increase the risk for these cancers.

Their main conclusion: vegetarians, pescatarians (eats fish, but no meat), and low-meat consumers did not have a reduced risk of lung, postmenopausal breast, and overall prostate cancer when compared with individuals consuming meat on a daily basis. This is after taking confounders such as smoking into account (because smokers have higher rates of cancers such as lung cancer).

The researchers do point out that some other similar studies had mixed results, but that perhaps those studies did not take confounders (variables that distort the results) such as smoking, physical activity levels, alcohol consumption, etc. into account.

From the European Journal of Clinical Nutrition: Vegetarianism, low meat consumption and the risk of lung, postmenopausal breast and prostate cancer in a population-based cohort study

The few prospective studies that examined lung, female breast and prostate cancer risk in vegetarians have yielded mixed results, whereas none have studied the effects of low meat diets. ... The Netherlands Cohort Study—Meat Investigation Cohort (NLCS-MIC)— is an analytical cohort of 11,082 individuals including 1133 self-reported vegetarians (aged 55–69 years at baseline). At baseline (1986), subjects completed a questionnaire on dietary habits and other risk factors for cancer and were classified into vegetarians (n=691), pescetarians (n=389), 1 day per week (n=1388), 2–5 days per week (n=2965) and 6–7 days per week meat consumers (n=5649).

After 20.3 years of follow-up, 279 lung, 312 postmenopausal breast and 399 prostate cancer cases (including 136 advanced) were available for analyses. After adjustment for confounding variables, we found no statistically significant association between meat consumption groups and the risk of lung cancer. As well, no significant associations were observed for postmenopausal breast and overall prostate cancer. After adjustment for confounders, individuals consuming meat 1 day per week were at a 75% increased risk of advanced prostate cancer compared with 6–7 days per week meat consumers.

Vegetarians, pescetarians and 1 day per week meat consumers did not have a reduced risk of lung, postmenopausal breast and overall prostate cancer compared with individuals consuming meat on a daily basis after taking confounders into account.

Although vegetarian diets are primarily defined by the absence of meat and fish, they are also shown to be associated with high intakes of fruits and vegetables and a favorable distribution of non-dietary factors.1, 2 Consequently, vegetarian diets may reduce the risk of different types of cancers through multiple mechanisms, depending on the etiology and preventability of the tumor.3, 4

We previously reported a nonsignificantly reduced risk of vegetarian and low meat diets on colorectal, and especially rectal, cancer5 and set out to study its effect on three other major cancers.

Although meat consumption has been hypothesized to be implicated in the etiology of lung, female breast and prostate cancer, data are not consistent across studies and meat subtypes.6, 7, 8However, on the basis of the existing body of literature, vegetarians may be at a lower risk of developing lung cancer (because of lower smoking rates) and to postmenopausal breast cancer (because of lower alcohol consumption, lower body mass index and higher physical activity levels).

Results from this prospective cohort study showed that, in age- and sex-adjusted models, vegetarians and pescetarians were at a reduced risk of lung cancer compared with individuals consuming meat on a daily basis. This effect disappeared after taking confounders, especially smoking, into account. We did not observe an association between the meat consumption group and the risk of post-menopausal breast and overall prostate cancer.

Our null findings regarding post-menopausal breast cancer risk are in line with other prospective studies comparing vegetarians with non-vegetarians and a pooled analysis of five cohort studies on breast cancer mortality. In contrast, the UK Women’s Cohort Study reported a lower post-menopausal breast cancer risk among non-meat consumers compared with high meat consumers,14 although this was not observed in their dietary pattern analyses.15 Vegetarian diets are rich in fiber and soy. Fiber was associated with a reduced risk of breast cancer in a meta-analysis of prospective studies,19 and soy contains isoflavones, which have previously been associated with a significant reduced risk of postmenopausal breast cancer in Asian populations.20 However, compared with the average soy intake in four Asian countries (ranging from 38 to 134 g/day21), the soy product intake among vegetarians in our population was likely too low to exert an effect (~15g per day).

Important new research was published in January 2016 about a fecal microbiota transplant (FMT) or "poop transplant". The research compared only one patient's gut microbes (thus a case study) to her fecal transplant donor's gut microbes, but it is important for looking at how gut microbes change long-term after a fecal microbiota transplant (poop transplant) and the actual length of time that it takes for the recipient's gut microbial community  to become like the donor's gut microbiome. The patient was quickly "cured" of a serious recurrent Clostridium difficile infection after one fecal micriobiota transplant (FMT) from her sister, but there were ongoing long-term changes in the patient's gut microbes for 4.5 years, at which point the microbes (bacteria and viruses) were like the donor's (at the phylum, class, and order levels), and with similar bacterial diversity. At this point the researchers said that "full engraftment" of microbes had occurred.

Until 7 months post-FMT, the  patient's microbial communities varied over time and showed little overall similarity to the donor, indicating "ongoing gut microbiota adaption" during the first seven months. But right after the transplant, the changes were enough for the patient to be immediately "cured" of her recurrent Clostridium difficile infection. The long-term results also suggested that phages (viruses) may play an important role in gut health. From Cold Spring Harbor Molecular Case Studies:

Long-term changes of bacterial and viral compositions in the intestine of a recovered Clostridium difficile patient after fecal microbiota transplantation

Fecal microbiota transplantation (FMT) is an effective treatment for recurrent Clostridium difficile infections (RCDIs). However, long-term effects on the patients’ gut microbiota and the role of viruses remain to be elucidated. Here, we characterized bacterial and viral microbiota in the feces of a cured RCDI patient at various time points until 4.5 yr post-FMT compared with the stool donor. Feces were subjected to DNA sequencing to characterize bacteria and double-stranded DNA (dsDNA) viruses including phages.

The patient's microbial communities varied over time and showed little overall similarity to the donor until 7 mo post-FMT, indicating ongoing gut microbiota adaption in this time period. After 4.5 yr, the patient's bacteria attained donor-like compositions at phylum, class, and order levels with similar bacterial diversity. Differences in the bacterial communities between donor and patient after 4.5 yr were seen at lower taxonomic levels.

C. difficile remained undetectable throughout the entire time span. This demonstrated sustainable donor feces engraftment and verified long-term therapeutic success of FMT on the molecular level. Full engraftment apparently required longer than previously acknowledged, suggesting the implementation of year-long patient follow-up periods into clinical practice. The identified dsDNA viruses were mainly Caudovirales phages. Unexpectedly, sequences related to giant algae–infecting Chlorella viruses were also detected. Our findings indicate that intestinal viruses may be implicated in the establishment of gut microbiota

FMT has shown impressive success rates of ∼90% against RCDIs and no severe adverse effects (Gough et al. 2011; Cammarota et al. 2014; O'Horo et al. 2014).... FMT led to increased donor-like intestinal bacterial diversities within 2 wk (van Nood et al. 2013).....Because viruses, especially phages, are the most abundant intestinal entities with the ability to influence microbial communities (Barr et al. 2013; Virgin 2014), they may well be relevant to C. difficile infection and the microbial changes following FMT.

Briefly, the female patient was 51 years old when admitted to the University Hospital of Zurich with her sixth episode of RCDI, suffering from severe diarrhea and weight loss.....Following FMT, the patient reported changes in bowel movements and intermittent obstipation, both of which ceased within 10 wk. Ever since, the patient has remained free of symptoms for almost 5 yr now.. 

The analysis of viral dsDNA sequences reported earlier revealed the presence of 22 viruses throughout samples D0, P1, P2, and P3 . In each sample, eight to 11 different viruses were identified, mainly belonging to the Caudovirales order (tailed dsDNA phages) that contains the viral families Myo-, Podo-, and Siphoviridae. Most viruses, 14 of 22, were identified uniquely in either sample. Three phages, the Erwinia phage vB_EamP-L1 (Podoviridae) and the two Bacteroides phages B124-14 and B40-8 (Siphoviridae), were consistently detected in all four samples and each contained phages of all three Caudovirales groups.

The bacterial composition of the donor was relatively stable and comparable at the time of FMT and 4.5 yr later (Fig. 1B), which is in accordance with the known temporal stability of adult intestinal microbiota (Zoetendal et al. 1998)....The patient's fecal microbiota underwent extensive compositional fluctuations and were dominated by Firmicutes up to 7 mo post-FMT, suggesting ongoing adaptation processes of donor microbiota in the patient's intestine that may also reflect changes in nutrition over the observation period. This is in accordance with our and other groups’ recent findings that showed high degrees of bacterial variation in RCDI patients up to 7 mo post-FMT (Broecker et al. 2013; Weingarden et al. 2015).

However, 4.5 yr post-FMT, the patient's bacteria have attained a donor-like composition at the phylum level, indicating full and stable engraftment of the donor's microbiota.....Of note, four of the five most prominent genera identified in both donor samples as well as the patient sample after 4.5 yr, Alistipes, Bacteroides, Dialister, and Faecalibacterium (Fig. 1D), are known constituents of healthy fecal microbiota (Claesson et al. 2011; Joossens et al. 2011). This further indicated that FMT led to healthy and sustainable microbiota in the patient.

One notable species detected in these three samples is Faecalibacterium prausnitzii (Fig. 1D). This species was also detected in the patient samples 6–7 mo post-FMT with abundances of <0.1% (data not shown). Faecalibacterium prausnitzii is recognized as one of the most important species of healthy individuals and normally constitutes >5% of the gut microbiota (Miquel et al. 2013). 

The fact that the patient's clinical symptoms, which included severe diarrhea in the absence of antibiotic treatment against C. difficile (Broecker et al. 2013), resolved promptly after FMT suggests that gut microbiota were able to exert normal metabolic functions even before full engraftment. This may be explained by the fact that the patient's bacterial diversity even during the highly variable time period up to 7 mo post-FMT was already in the range of the healthy donor. In agreement with the absence of symptoms until today, C. difficile bacteria were undetectable in the samples of the patient, similar to the donor who tested negative for C. difficile before FMT.....The finding that the patient's fecal microbiota attained a highly donor-like composition after 4.5 yr suggests that long-term follow-up should be implemented into clinical practice. 

The analysis of viral dsDNA sequences from a previous study revealed the presence of Caudovirales phages in all investigated samples of the donor and the patient. Caudovirales have been shown before to be the dominant viruses in the human intestine, followed by ssDNA phages of the Microviridae family that we were unable to detect with the metagenomic sequencing approach (Lepage et al. 2008; Norman et al. 2015). Three phages were identified in all of the analyzed samples of the donor and the patient. 

Another community of microbes found in humans in areas once thought to be sterile (without bacteria) - the ovaries and fallopian tubes in the female upper reproductive tract. And the interesting thing is that once again we see differences in the bacterial communities of areas with and without cancer (here the ovaries). From Science Daily:

Bacteria found in female upper reproductive tract, once thought sterile

They're inside our gut, on the skin, and in the mouth. Thousands of different types of micro-organisms live in and on the body, playing helpful roles in digestion or in aiding the body's natural defense system. Now, scientists at the University of North Carolina Lineberger Comprehensive Cancer Center have found tiny organisms living in the upper female reproductive tract, an environment they said was once thought to be sterile.

In a preliminary finding (abstract 5568) presented Monday, June 6, at the 2016 American Society of Clinical Oncology Annual Meeting in Chicago, researchers revealed they have found bacteria in the ovaries and in the fallopian tubes. And with an additional finding that women with ovarian cancer have a different bacterial makeup, researchers are asking whether these tiny organisms could play a role in cancer development or progression.

To test whether there were bacteria in the upper female reproductive tract, researchers gathered samples from 25 women with and without cancer who were undergoing surgery to either have their uterus, fallopian tubes, or ovaries removed. The researchers then used genetic sequencing to determine what types of bacteria were present....Genetics-based approaches to identifying bacteria have made studies like theirs possible, Keku said, as some bacteria cannot be grown outside of the body in the laboratory.

From their analysis, the researchers found different types of bacteria in the fallopian tube and ovary. They also found differences in the types of bacteria in the upper reproductive tracts of women with and without epithelial ovarian cancer. Keku said the bacterial strains in the women with ovarian cancer were more pathogenic. The findings were borderline statistically significant, which the researchers said suggested a trend.

While they said it's too early to tell if the bacterial differences play a role in cancer development, researchers said their proof-of-concept study is a step needed to answer that question. Further studies are needed to determine if changes in the type of bacteria and other organisms in those regions come before the development of cancer.

Human female ovary and Fallopian tube. Credit: Wikipedia

Some researchers are now testing to see if phage therapy  could be a possible treatment for some conditions, such as chronic sinusitis and wound infections. Phage therapy, which uses bacteriophages, was neglected for decades (except for Russia and the Republic of Georgia), but their use is again being studied as an alternative to antibiotics. A bacteriophage is a virus that lives within a bacterium, replicating itself, and eventually destroys the bacteria. The term is from "bacteria" and the Greek "phagein" which means to devour, so think of them as "bacteria eaters". Phages only attack specific types of bacteria (they are "bacterium specific"), so they’re unlikely to harm the normal microbiome (community of microbes) or any human cells.

I've been posting about the beneficial bacteria Lactobacillus sakei that treats chronic sinusitis, as well as some other probiotic (beneficial) bacteria that people have reported success with (see The One Probiotic That Treats Sinusitis). Most people contacting me or commenting have reported success with L. sakei products, but there is a group for whom L. sakei and other probiotics haven't helped. Why? And what can be done? Perhaps their sinuses are missing still unknown "keystone" species (very important microbial species for health). Or perhaps they have bacterial biofilms that even Lactobacillus species that are viewed as anti-biofilm cannot overcome. Perhaps phage therapy might help these people? 

Phage therapy is currently being tested by researchers in the treatment of chronic sinusitis in Australia. The video Antibiotic Resistance discusses phage therapy for sinusitis starting at 23:30. Looks promising.

And a write-up about the sinusitis phage therapy research from the Australian newspaper The Sydney Morning Herald: Medicine turns to bacteriophage therapy to beat superbugs

An arcane therapy for bacterial infections that dwelled behind the Iron Curtain for decades is making a comeback in Western medicine as a potential white knight against superbugs. Phage therapy involves infecting patients with viruses known as bacteriophages, which are the natural predators of bacteria, to kill the germs that antibiotics cannot.  ...continue reading "Phage Therapy May Help Sinusitis Sufferers"

New research looked at people who "aged successfully" over a 10 year period compared with those who were "suboptimal agers" or had died. The successful agers were less likely to smoke, and have higher intakes of fiber from fruits, breads, and cereals (primarily from rolled oats and whole grain breads), but not from vegetables. Successful aging was defined as including an absence of disability, depressive symptoms, cognitive impairment, respiratory symptoms, and chronic diseases including cancer, coronary artery disease, and stroke. Fiber intake was more important for successful aging than glycemic index, glycemic load, carbohydrate intake, or sugar intake. From Medical Xpress:

Dietary fiber intake tied to successful aging, research reveals

A new paper—published in The Journals of Gerontology, Series A: Biological Sciences and Medical Sciences by scientists from The Westmead Institute for Medical Research—reports that eating the right amount of fiber from breads, cereals, and fruits can help us avoid disease and disability into old age

Using data compiled from the Blue Mountains Eye Study, a benchmark population-based study that examined a cohort of more than 1,600 adults aged 49 years and older for long-term sensory loss risk factors and systemic diseases, the researchers explored the relationship between carbohydrate nutrition and healthy aging.

They found that out of all the factors they examined—which included a person's total carbohydrate intake, total fiber intake, glycemic index, glycemic load, and sugar intake—it was the fiber that made the biggest difference to what the researchers termed "successful aging." Successful aging was defined as including an absence of disability, depressive symptoms, cognitive impairment, respiratory symptoms, and chronic diseases including cancer, coronary artery disease, and stroke.

"Out of all the variables that we looked at, fiber intake—which is a type of carbohydrate that the body can't digest—had the strongest influence," she said. "Essentially, we found that those who had the highest intake of fiber or total fiber actually had an almost 80 percent greater likelihood of living a long and healthy life over a 10-year follow-up. That is, they were less likely to suffer from hypertension, diabetes, dementia, depression, and functional disability."

While it might have been expected that the level of sugar intake would make the biggest impact on successful aging, Gopinath pointed out that the particular group they examined were older adults whose intake of carbonated and sugary drinks was quite low.

This study backs up similar recent findings by the researchers, which highlight the importance of the overall diet and healthy aging. In another study published last year in The Journals of Gerontology, Westmead Institute researchers found that, in general, adults who closely adhered to recommended national dietary guidelines reached old age with an absence of chronic diseases and disability, and had good functional and mental health status.

An new analysis of published studies found that air pollution is linked to high blood pressure. Yes, breathing polluted air has health effects (here, here, and here). From Science Daily:

High blood pressure linked to short-, long-term exposure to some air pollutants

Both short- and long-term exposure to some air pollutants commonly associated with coal burning, vehicle exhaust, airborne dust and dirt are associated with the development of high blood pressure, according to new research in the American Heart Association's journal Hypertension. "In our analysis of 17 previously-published studies we discovered a significant risk of developing high blood pressure due to exposure to air pollution," said Tao Liu, Ph.D., lead study author and deputy director and epidemiologist of the environmental health division at Guangdong Provincial Institute of Public Health in China.

Researchers performed a meta-analysis of available published studies in the world assessing the health effects of all air pollution on hypertension risk. Meta-analyses combine results from previous studies to estimate the overall effect of a particular variable on a result.....researchers focused on these air pollutants: sulfur dioxide (SO2), which mainly comes from the burning of fossil fuel; nitrogen oxide (NOx), which comes from fossil fuels burned at power plants and vehicle exhaust; Particulate matter (PM) are particles found in the air, including dust, dirt, smoke and liquid droplets. (PM 2.5 is smaller than a speck of dust, and the most common and hazardous type of air pollution. PM10 includes both PM2.5 and PM2.5-10).

The meta-analysis found high blood pressure was significantly associated with: short-term exposure to sulfur dioxide (SO2), PM2.5 and PM10; and long-term exposure to nitrogen dioxide (NO2), which is produced from combustion, and PM10. For the portion of the study that assessed short-term effects of ozone and carbon monoxide exposure, no significant associations were found. Researchers said ozone and carbon monoxide's links to high blood pressure requires further study.

Of the 5,687 air pollution studies initially identified, 17 were the focus of this -- which involves more than 108,000 hypertension patients and 220,000 non-hypertensive controls. High blood pressure was defined as systolic blood pressure more than 140 mm Hg and/or diastolic blood pressure over 90 mm Hg or by antihypertensive drug use. Air pollution exposure was assessed by averaging data from nearest air pollution monitoring stations, or using complex dispersion models or land use regression models.

High blood pressure is a major risk factor for cardiovascular disease and stroke. Previous studies have indicated that air pollution might be a risk factor for hypertension but the results were controversial, Liu said. The mechanism by which air pollution could contribute to the development of high blood pressure includes inflammation and oxidative stress, which may lead to changes in the arteries.