(Reuters Health) – Older adults with a poor sense of smell may die sooner than their counterparts who have keen olfactory abilities, a U.S. study suggests.
Researchers asked 2,289 adults, ages 71 to 82, to identify 12 common smells, awarding scores from zero to as high as 12 based on how many scents they got right. When they joined the study, none of the participants were frail: they could walk a quarter mile, climb 10 steps, and independently complete daily activities.
During 13 years of follow-up, 1,211 participants died.
Overall, participants with a weak nose were 46 percent more likely to die by year 10 and 30 percent more apt to pass away by year 13 than people with a good sense of smell, the study found.
“The association was largely limited to participants who reported good-to-excellent health at enrollment, suggesting that poor sense of smell is an early and sensitive sign for deteriorating health before it is clinically recognizable,” said senior study author Dr. Honglei Chen of Michigan State University in East Lansing.
“Poor sense of smell is likely an important health marker in older adults beyond what we have already known about (i.e., connections with dementia, Parkinson’s disease, poor nutrition, and safety hazards),” Chen said by email.
People who started out the study in excellent or good health were 62 percent more likely to die by year 10 when they had a poor sense of smell than when they had a keen nose, researchers report in the Annals of Internal Medicine.
But smell didn’t appear to make a meaningful difference in mortality rates for people who were in fair to poor health at the start of the study.
With a poor sense of smell, people were more likely to die of neurodegenerative and cardiovascular diseases, but not of cancer or respiratory conditions.
Poor sense of smell may be an early warning for poor health in older age that goes beyond neurodegenerative diseases that are often signal the beginning of physical or mental decline, the results also suggest.
Dementia or Parkinson disease explained only 22 percent of the higher death risk tied to a poor sense of smell, while weight loss explained just six percent of this connection, researchers estimated. That leaves more than 70 percent of the higher mortality rates tied to a weak nose unexplained.
The connection between a poor sense of smell and mortality risk didn’t appear to differ by sex or race or based on individuals’ demographic characteristics, lifestyle, and or chronic health conditions.
One limitation of the study is that the older adult participants were relatively functional, making it possible results might differ for younger people or for frail elderly individuals, the study team writes.
Researchers also only tested smell at one point in time, and they didn’t look at whether changes in olfactory abilities over time might influence mortality. Researchers also lacked data on certain medical causes of a weak nose such as nasal surgery or chronic rhinosinusitis that are not related to aging.
“The take-home message is that a loss in the sense of smell may serve as a bellwether for declining health,” said Vidyulata Kamath of the Johns Hopkins University School of Medicine in Baltimore, co-author of an accompanying editorial.
“As we age, we may be unaware of declining olfactory abilities,” Kamath said by email. “Given this discrepancy, routine olfactory assessment in older adults may have clinical utility in screening persons at risk for illness, injury or disease for whom additional clinical work-up and/or intervention may be warranted.”
Lisa Rapaport APRIL 29, 2019
SOURCE: bit.ly/2vrDJkP Annals of Internal Medicine, online April 29, 2019.
Humans Smell With Their Tongues, Scientists Discover
The receptors that dot our noses and help us to smell also populate our tongues, according to a new study. Researchers at the Monell Chemical Senses Center have discovered working olfactory (smell) receptors in the taste-sensing cells on the papillae of the tongue. The findings were published in the journal Chemical Senses.
It is thought that the systems that enable us and other mammals to taste and smell are separate, and our brains combine this information so we can experience flavor. While the tongue deals with whether food is salty, sweet, sour, bitter, or umami, our noses provide more detail from smells.
As such, the study calls into question whether the mixing of smell and taste first happens in the brain. Instead, it provides evidence suggesting the process that creates flavor may first happen in the tongue.
However, Dr. Mehmet Hakan Ozdener, senior study author and a cell biologist at Monell Chemical Sense Center, stressed to The Guardian: “I am not saying that [if you] open your mouth, you smell.”
He said in a statement: “Our research may help explain how odor molecules modulate taste perception. The presence of olfactory receptors and taste receptors in the same cell will provide us with exciting opportunities to study interactions between odor and taste stimuli on the tongue.”
To arrive at their conclusion, scientists used genetic and biochemical tests to study human taste cells in a lab. They also used calcium imaging, which showed taste cells react to smells similarly to cells which pick up odor.
Ozdener was inspired to carry out the research after his 12-year-old son asked him if snakes waggle their tongues out of their mouths to smell.
The team hopes the research could help to combat the obesity epidemic, by creating flavor without the need for heaps of delicious yet unhealthy ingredients.
“This may lead to the development of odor-based taste modifiers that can help combat the excess salt, sugar, and fat intake associated with diet-related diseases such as obesity and diabetes,” he said.
The team also hopes their work will shed light on the little-understood olfactory system, which contains around 400 different receptors which enables us to smell.
Earlier this week, a separate team published a study showing humans use their sense of smell to navigate space. The scientists behind the study published in the journal Neuron created a “smellscape” in a room featuring the scent of pine and banana, which participants moved around.
VANCOUVER—A simple shift in attitude could improve a lot for the world’s elderly population, according to a new global study.
That’s because how well we age is connected to how we view old age, the study stated, noting those with a positive attitude toward old age are likely to live longer — up to eight years — than their negative counterparts.
And older people in countries with low levels of respect for seniors are at risk for worse mental and physical health as well as higher levels of poverty, the Orb Media study found. By compiling global data, researchers also surveyed 150,000 people in 101 countries to discover levels of respect for older adults, which varied from country to country.
Canada ranked in the lower third of all for respect, along with Japan, the United Kingdom and the United States.
But one British Columbian expert pointed out that the study may not entirely reflect Canada’s position with the elderly.
“Our human rights legislation, federally and provincially provide protections against age discrimination,” said Christopher McLeod, associate professor at the University of British Columbia’s school of population and public health. “And many countries do not have these protections.”
McLeod said the association between negative views on aging and the relationship to health “made a lot of sense.” But he warned about statements of causality with specific attitudes toward health decline.
Despite that, seniors’ loneliness and social exclusion are key risk factors leading to declined health, he added. A 2017 report by the Vancouver Foundation found that people report high levels of social isolation and loneliness, noting a decline in community participation over the last five years.
“When we think about determinants of health, there are features in our society that are influenced by social or policy decisions, like income, education, your employment and its conditions,” McLeod said. “What we know now, is many of those things are far more important in terms of determining an individual’s health than medical care.”
The world is facing a rapidly aging population —
by 2050, roughly one in six people will be over 65.
Countries everywhere are aging rapidly, and if trends continue, by 2050 roughly one out of six people will be over 65 and nearly half a billion will be older than 80, the report noted. Yet, public debate about this demographic shift is often focused on the anticipated economic and social challenges.
Analysis from the World Health Organization found that 60 per cent of people surveyed across 57 countries reported low levels of respect for seniors, viewing them less competent than the young and considering them a burden on society and their families.
Something as simple as how you think about aging can have a huge range of health factors, said Jim Rendon, a journalist with Orb Media.
“There’s less likelihood of dementia, heart attacks and a longer life span according to research out of Yale University,” he said. “If you have a positive attitude, you’re more likely to recover quickly from a disabling accident, like a broken hip. And less likely to be depressed and anxious.”
And the report dispelled some of the cultural myths in the East and West, Rendon said. In fact, the research found the West had more respect for the elderly than eastern countries. He cited the example of Japan — at the leading edge of the demographic shift with low birth rates and long life spans — but ranked low when it came to social respect for seniors.
But in Pakistan, well-being was less associated with youth and Rendon speculated that might have something to do with cultural traditions such as extended families living with older adults.
“Intergenerational relationships can be very helpful in terms of breaking down the stereotypes about age,” he said.
Notably, the study revealed no meaningful connection between the gross income of a country and level of respect. Rendon said that indicates respect is not limited to economic status.
To understand how attitude may impact health, he pointed to studies about biomarkers of stress: The more negative the attitude the higher the stress level. In addition, Rendon said “if you think you’re going to have an active life, you just take care of yourself better.”
And you don’t need to be “old” to have a positive attitude age: Studies out of Yale University followed people in their twenties through a lifetime and found that those with a positive view were less likely to have a heart attack in their 60s.
“That brought home the idea that it’s not just what you think when you’re old,” he said. “But it’s how you perceive aging.”
By MELANIE GREEN StarMetro Vancouver Wed., June 13, 2018
Big changes like cutting out all carbs or training for a marathon are great—but you don’t have to remake yourself to have a dramatic impact on your health. Try a few of these baby steps to get you started in the right direction.
Add a fruit or veggie to every meal
Not ready to give up a bad habit yet? Start by creating an easy good-for-you habit instead. “Less than one in three individuals gets even two servings of fruits and vegetables per day,” says Erin Palinski-Wade, RD, CDE, LDN, CPT, author of 2 Day Diabetes Diet. “By adding one serving to each meal, you can get in at least three servings per day and be ahead of the curve. A half of a banana on your breakfast cereal, a small side salad with your sandwich at lunch, and adding 1/2 cup of cooked veggies into your pasta can pack in more fiber, antioxidants, and nutrients—all which have been found to reduce the risk of heart disease, type 2 diabetes, and even certain cancers.”
Work on your hips
“If you have a sedentary job, focus on some hip opening exercises to start and end your day,” suggests trainer Jonathan Hertilus, ACE, owner of BFF Bootcamp in Nutley, NJ. “For instance,” says Hertilus, “hip bridges can be done anywhere—even in bed—as soon as you wake up or right before you go to sleep.” Just a few minutes of hip exercises can do wonders to keep your back and core muscles engaged.
Lose a little weight
Setting a goal to lose 40 pounds or more to get out of the “overweight” category can be daunting. So aim for smaller, more attainable goals, which can make a big difference in your overall health. “Small steps can be very powerful,” says Jill Crandall, MD, professor of endocrinology at Albert Einstein College of Medicine and an attending physician at Montefiore Health System.” For people who are at increased risk for type 2 diabetes, which includes many adults who are overweight and have a family history of diabetes, modest changes can reduce the risk of developing diabetes by over 50 percent.” Dr. Crandall suggests focusing on losing about 7 percent of your overall weight—or about 15 pounds for a 200-pound person.
Lighten your load
Cleaning out your purse or backpack could go a long way toward preventing neck, back, and shoulder pain. When you are carrying things, balance your load, and avoid backpacks or purses with more than 10 percent of your body weight,” suggests Robert Hayden, DC, PhD, a chiropractor in Griffin, Georgia.
Be careful with condiments
You might want to take a second to consider before you slather your next salad in ranch dressing. “Ketchup, barbecue sauce, mayo, and salad dressings can all be a major source of calories, sodium, fat, and added sugar,” says Palinski-Wade. “Opt for condiments on the side, rather than on your meal and read those labels!”
Skimp on the sugar—and pump up your probiotics
More and more studies show that sugar wreaks havoc on your health, including slowing your metabolism, impairing brain function, and increasing your risk of heart disease and cancer. But there are other health issues you can keep at bay with a little less sugar and a little more healthy bacteria. “Decreasing intake of sugar and processed food as well as taking probiotics can help decrease yeast infections,” says Jessica Shepherd, MD, MBA, OB/GYN, director of minimally invasive gynecology at University of Illinois at Chicago.
Straighten up your sleep habits
A bad sleep posture could make for more aches and pains when you’re awake. “Most of us don’t really think much about posture while we are asleep—but really, posture while you are asleep is at least as important as when you are awake because the muscles that protect your joints are quite loose while you are asleep,” says Dr. Hayden. “I recommend sleeping in a side posture whenever possible. Make sure your pillow is firm and just high enough to keep your head level with the mattress so that your head is neither pushed up nor down. Use a body pillow to hug, throwing your upper arm and upper knee over the pillow so that the pillow supports the weight of the extremities while you are asleep. This prevents you from inducing torque into the lumbar spine and offloads the weight of the upper extremity from the structures at the base of the neck. This simple approach to rest keeps your body straight and as stress free as possible while you catch those zzzs.”
Drink half your weight in water
We should all be drinking more water, but the old saw about eight glasses of eight ounces of water doesn’t work for everybody. The better formula? “Take your weight in pounds and divide by two, and you will get the number of ounces of water you should drink every day,” says Mitzi Dulan, RD, founder of simplyFUEL. “Start your day with a big glass of ice water. Ice cold water can boost your metabolism slightly because it takes energy for your body to get it to room temperature—drink six glasses of 16 ounces of cold water and burn an extra 100 calories per day.”
Stop the midnight snacking
“Avoid eating after 8 p.m.,” says Dulan. “Often times, late-night eating is really boredom eating. This helps your body focus on burning the fat during the night instead of trying to work to digest the food you just ate before nodding off.”
Shut off your electronics an hour before bedtime
Those last hours before bed may seem like the perfect time to catch up on some work or binge watch a little of your favorite show, but experts say that the light emanating from your screens could be disrupting your sleep. That wavelength of light disrupts melatonin production, and tricks your body into thinking it’s daylight, according to Mark Buchfuhrer, MD, medical director of the Comprehensive Sleep Center at Good Samaritan Hospital in Los Angeles. The fix? Skip the screens and tuck into a good book, do relaxed stretching, or find another way to unwind in the last hour before your bedtime.
Trade refined carbs for whole grains
“Most people eat plenty of grains, but most Americans consume only one serving of whole grains per day,” says Palinski-Wade. “By swapping out a few refined grains for whole grains, you may reduce your waist circumference and reduce the risk of heart disease and diabetes. If you use white bread for a sandwich, switch to rye. If you like rice, opt for brown rice over white rice. A simple switch can add up significantly.”
Take breaks when you’re traveling
Whether you travel by car or plane, taking frequent breaks to walk and stretch is essential. When flying by air, it can reduce your risk of developing a dangerous blood clot in your leg, called a deep vein thrombosis. “I coach our patients who are driving long-distance to get out of the vehicle periodically and walk around it a few laps,” Dr. Hayden says. “Find a bumper that is the right height to put one foot on it. Step back about two feet, square the pelvis, and lean toward the foot that is on the bumper. This has the effect of a hurdler’s stretch, and it will help stretch those gluteals on which you have been sitting as well as the quadriceps and many of the extensor muscles in the back. Always stretch both sides—if you leave one side tight, you may find yourself walking in circles!”
Cut down on the cocktails
Those studies that show red wine’s positive health benefits may encourage us to raise a few more glasses, but there are really good reasons to limit your alcohol intake, including increased risk of high blood pressure and high cholesterol levels, and obesity. Cutting back on the booze can decrease the risk of many different kinds of cancer, including breast cancer, according to Dr. Shepherd. For women, one drink a day seems to be the healthy max, while men can have two.
Start squatting
“Everyone asks me to recommend one exercise that everyone can do to improve their overall health,” says Pat McGuinness, personal trainer at the MAX Challenge in Montclair, NJ, and regional director of programming for New York Sports Clubs. “My answer is always squats! Everyone can do them—modifications are easy—and leg muscles make up more than 60 percent of our total body composition, which means you get more bang for your buck!”
Walk for five minutes every hour at work
Studies have shown that a sedentary lifestyle can wreak havoc on your health. If you can’t get a standing desk to help you limit your time on your seat, make sure you take a five-minute walk break every hour. That can help you minimize the impact of sitting on your health, and ensure you get even more than the doctor-recommended 150 minutes of exercise per week. That can help you reduce the risk of type 2 diabetes, according to Dr. Crandall.
Swap soda for fruit-spiked water
Whether it’s diet or sugar-filled, study after study shows that soda isn’t the best beverage—unless you want to gain weight, increase your risk of developing diabetes, cancer, or heart disease, and reduce your bone density. But you don’t have to sacrifice flavor if you give up your soda. “Infuse water with fruit for a tasty alternative that’s sure to impress and refresh,” says McGuinness.
There’s a link between your emotional health and your physical well-being, so take time to nurture both.
To be completely healthy, you should take care not only of your physical health, but your emotional health, too. If one is neglected, the other will suffer.
What’s the Connection Between Emotional and Physical Health?
There’s a physical connection between what the mind is thinking and those parts of the brain that control bodily functions. According to Charles Goodstein, MD, a clinical professor of psychiatry at New York University’s Langone School of Medicine in New York City, the brain is intimately connected to our endocrine system, which secretes hormones that can have a powerful influence on your emotional health. “Thoughts and feelings as they are generated within the mind [can influence] the outpouring of hormones from the endocrine system, which in effect control much of what goes on within the body,” says Dr. Goodstein.
“As a matter of fact, it’s very probable that many patients who go to their physician’s office with physical complaints have underlying depression,” he says. People who visit their doctors reporting symptoms of headache, lethargy, weakness, or vague abdominal symptoms often end up being diagnosed with depression, even though they do not report feelings of depression to their doctors, says Goodstein.
While unhappy or stressed-out thoughts may not directly cause poor physical health, they may be a contributing factor and may explain why one person is suffering physically while someone else is not, Goodstein adds.
How Exactly Does the Mind Affect the Body?
There are many ways in which the mind has a significant impact on the body. Here are a few:
Chronic illness and depression Depression has been shown to increase the risk for chronic illnesses, such as heart disease, stroke, cancer, and diabetes, according to an article published in 2013 in the Primary Care Companion for CNS Disorders. A review of studies on diabetes and depression, published in August 2015 in the Canadian Journal of Diabetes, found that depression put people at a 41 percent higher risk for the condition. Researchers aren’t yet clear on how mental health influences physical health, but according to a study published in September 2017 in the journal Psychiatria Danubina, it may be that depression affects the immune system, and that habits associated with depression, such as poor diet or lack of physical activity, may create conditions for illness to occur.
Depression and longevity According to a review published in June 2014 in World Psychiatry, many major mental illnesses are associated with higher rates of death. Another study, published in October 2017 in the Canadian Medical Association Journal, suggests that those with depression may have life spans from about 7 to 18 years shorter than the general population.
Physical symptoms of emotional health distress People who are clinically depressed often have physical symptoms, such as constipation, lack of appetite, insomnia, or lethargy, among others.
White-coat syndrome This is a condition in which a person’s blood pressure increases the minute they step into a doctor’s office. In white-coat syndrome, anxiety is directly related to physical function — blood pressure. “If you extrapolate from that, you can say, what other kinds of anxieties are these people having that are producing jumps in blood pressure? What is the consequence of repeated stress?” asks Goodstein.
And on the other hand: “Those individuals who have achieved a level of mental health where they can manage better the inevitable conflicts of human life are more likely to prevail in certain kinds of physical illness,” says Goodstein.
How Should You Care for Your Emotional and Physical Well-Being?
It’s hard to do, but slowing down and simplifying routines can go a long way to strengthening your mental and physical health.
Eat right. A healthy, regular diet is good for the body and mind.
Go to bed on time. Losing sleep is hard on your heart, may increase weight, and definitely cranks up the crankiness meter.
If you fall down, get back up. Resilience in the face of adversity is a gift that will keep on giving both mentally and physically.
Go out and play. Strike a balance between work and play. Yes, work is a good thing: It pays the bills. However, taking time out for relaxation and socializing is good for your emotional health and your physical health.
Exercise. A study published in October 2017 in Reviews in the Neurosciences shows that exercise improves your mood and has comprehensive benefits for your physical health.
See the right doctor, regularly. Going to the right doctor can make all the difference in your overall health, especially if you have a complicated condition that requires a specialist. But if your emotions are suffering, be open to seeing a mental health professional, too.
Total health depends on a healthy mind and body. Take time to nurture both.
An analysis of published studies indicates that following the Mediterranean diet may reduce the risk of frailty in older individuals. The findings, which are published in the Journal of the American Geriatrics Society, suggest that a diet emphasizing primarily plant-based foods — such as fruits and vegetables, whole grains, legumes, and nuts — may help keep people healthy and independent as they age.
Frailty is common among older people and its prevalence is increasing as the population ages. Frail older adults may often feel low in energy and have weight loss and weak muscle strength. They are more likely to suffer from numerous health concerns, including falls, fractures, hospitalization, nursing home placement, disability, dementia, and premature death. Frailty is also associated with a lower quality of life.
Nutrition is thought to play a crucial role in developing frailty, a team led by Kate Walters, PhD and Gotaro Kojima, MD, of University College London, in the UK, looked to see if following a healthy diet might decrease one’s risk of frailty.
The researchers analyzed evidence from all published studies examining associations between adherence to a Mediterranean diet and development of frailty in older individuals. Their analysis included 5789 people in four studies in France, Spain, Italy, and China.
“We found the evidence was very consistent that older people who follow a Mediterranean diet had a lower risk of becoming frail,” said Dr. Walters. “People who followed a Mediterranean diet the most were overall less than half as likely to become frail over a nearly four-year period compared with those who followed it the least.”
The investigators noted that the Mediterranean diet may help older individuals maintain muscle strength, activity, weight, and energy levels, according to their findings. “Our study supports the growing body of evidence on the potential health benefits of a Mediterranean diet, in our case for potentially helping older people to stay well as they age,” said Dr. Kojima.
Although older people who followed a Mediterranean diet had a lower risk of becoming frail, it’s unclear whether other characteristics of the people who followed this diet may have helped to protect them. “While the studies we included adjusted for many of the major factors that could be associated – for example, their age, gender, social class, smoking, alcohol, how much they exercised, and how many health conditions they had — there may be other factors that were not measured and we could not account for,” said Dr. Walters. “We now need large studies that look at whether increasing how much you follow a Mediterranean diet will reduce your risk of becoming frail.”
Story Source: Materials provided by Wiley. Note: Content may be edited for style and length. Date: January 11, 2018
Journal Reference: Gotaro Kojima, Christina Avgerinou, Steve Iliffe, Kate Walters. Adherence to Mediterranean Diet Reduces Incident Frailty Risk: Systematic Review and Meta-Analysis. Journal of the American Geriatrics Society, 2018; DOI: 10.1111/jgs.15251
Every year spent in education adds an average of 11 months to people’s lifespan, say scientists.
The researchers say a person loses two months for every kilogram overweight they are – and seven years for smoking a packet of cigarettes a day.
Unusually, the Edinburgh university team found their answers by analysing differences in people’s genetic code or DNA.
Ultimately they think it will reveal new ways of helping us to live longer.
The group used the genetic code of more than 600,000 people who are taking part in a natural, yet massive, experiment.
Clearer picture
If someone smokes, drinks, dropped out of school and is overweight, it can be difficult to identify the impact of one specific unhealthy behaviour.
Instead, the researchers turned to the natural experiment.
Some people carry mutations in their DNA that increase appetite or make them more likely to put on weight, so researchers were able to compare those programmed to eat more with those who were not – irrespective of their wider lifestyles.
Dr Peter Joshi, from the university’s Usher Institute, said: “It doesn’t mess up the analysis. You can look directly at the effect of weight, in isolation, on lifespan.”
Similar sets of mutations have been linked to how long people spend in education and the enjoyment they get from smoking or drinking.
The research team also found specific mutations in human DNA that alter lifespan, reported in the journal Nature Communications.
Mutations in a gene (a set of instructions in DNA) that is involved in running the immune system could add seven months of life on average
People with a mutation that increased levels of bad cholesterol knocked eight months off life expectancy
A rare mutation in a gene – APOE – linked to dementia reduced lifespans by 11 months
And one that made smoking more appealing cut lives by five months
Dr Joshi says these genetic variants are the “tip of the iceberg”. He says around 20% of the variation in lifespans may be inherited, but only 1% of such mutations have yet been found.
However, he said that while genetics does influence lifespan, “you’ve got even more influence” through the choices you make.
Dr Joshi told the BBC: “We hope to discover novel genes affecting lifespan to give us new information about ageing and construct therapeutic interventions for ageing.”
There are also some disease mutations that clearly affect life expectancy, and to devastating effect, such as the Huntington’s gene. People with Huntington’s often die in their 20s.
However, in order to follow people until the end of their lives, many of the people studied were born before 1940.
Prof David Melzer, from the University of Exeter Medical School, said: “An extra year of education then may have been much more important than it is now.”
By James Gallagher Health and science reporter, BBC News website 13 October 2017
Not just parks but also streetside trees and lawns could have health benefits, study suggests
Trees stretching their canopies over city streets and grass tickling the sidewalk near your home are more than just pretty, they could actually be helping you live longer, a new study suggests.
Researchers at the University of New Brunswick used census and tax data to track 1.3 million non-immigrant Canadian adults living in the 30 biggest cities across the country, from Victoria to St. John’s, over 11 years starting in 2001. They measured the amount of greenery from trees, shrubs, grass and other plants within 250 metres (about two blocks) of the study subjects’ homes, using postal codes and satellite data. And they found that as the amount of greenery increased, people’s risk of death decreased “significantly” from natural causes.
“There was a lot bigger effect than I think any of us had been expecting,” said Dan Crouse, a health geographer and lead author of the study published this week in the journal The Lancet Planetary Health.
‘Really, just having trees around where people are living is really important.’ – Dan Crouse, University of New Brunswick
Using NASA’s Aqua satellite, the greenery was measured on a scale of 0 to 1. (Zero represented bare ground; 1 was complete coverage by dark green leafy plants.) The study found that each 0.15-point increase in greenness near the subjects’ homes was associated with an eight to 12 per cent decrease in the risk of death.
Crouse said the link between greenness and lower death rates remained even after researchers accounted for the effects of air pollution.
While previous studies have shown that exposure to green space and parks can improve mental health and in some cases physical health, the researchers say this is the first big study to show a clear link between green surroundings and a lower risk of death.
It also suggests that green spaces don’t have to be actual parks in order to have health benefits.
“What we’re able to show with this study is really just having trees around where people are living is really important,” Crouse said.
The study found that the positive effect of green surroundings was greater for people in middle age than in other age groups.
The effect was also greater among those with higher incomes and more education, and among men compared to women. The researchers aren’t sure why.
The study also couldn’t tell what kind of greenery was being measured, although trees gave a higher score than grass. Nor could it explain why exposure to greenery had that kind of effect — researchers didn’t know how much access people had to the green spaces or whether they were getting more exercise in greener areas, for example.
View of nature
But Crouse said there are benefits to living near green spaces such as golf courses even for people who don’t use them.
“That space is still representing an absence of traffic congestion, an absence of the noise and pollution from cars. It’s going to have a real cooling effect in an urban area,” he said. “Just having a view of nature from your window … can be restorative. There’s a lot of ways that the greenness could be benefiting your health.”
Dr. Gillian Booth is a researcher at St. Michael’s Hospital who recently found that people who live in more walkable city neighbourhoods have lower rates of diabetes and obesity. She says the design of Crouse’s study looks sound, and she has used similar techniques in her own work.
She added that the results make her wonder what it is about green surroundings that are lowering death rates, and what threshold of greenness is needed to get those health benefits.
“Where do you draw the line and say there’s insufficient green space? And how much should you invest in it?” she said. “I think this is really exciting work in that it raises these types of questions.”
The study, she added, highlights that the way we design our communities can have a profound influence on residents’ health: “The potential reach is huge in terms of the number of people who could be benefiting from these health effects.”
By Emily Chung, Science and Technology Writer CBC News Oct 12, 2017
