Tag: Harvard Medical School

Categories
News on Health & Science

Weighing the Value of Organic Foods

[amazon_link asins=’B002FYAN06,B01M304650,B0030VBRIU,B00JOEAJ2M,B00XCLFZLS,B00MQVY94Y,B00A3OT860,B00TZITZPO,B00BN1U7P8′ template=’ProductCarousel’ store=’finmeacur-20′ marketplace=’US’ link_id=’a4c49259-7fea-11e7-9785-071caa3609b7′]

Food produced without most conventional pesticides or fertilizers are perceived to be more healthful, but scientists have yet to offer proof.

With the recession breathing down our necks, many people are looking for ways to cut the household budget without seriously compromising family well-being. So here’s a suggestion: If you buy organic fruits and vegetables, consider switching to less pricey non-organic produce instead.

Hold the e-mails and hear me out: There really is no proof that organic food, which costs about a third more, is better than the conventionally grown stuff.

It may seem, intuitively, that crops grown without pesticides should be better for us and that food grown the old-fashioned way, by rotating crops and nurturing the soil naturally, would be superior to food that is mass-produced and chemically saturated.

Many people feel that way. Annual sales of organic food and beverages grew from $1 billion in 1990 to well over $20 billion in 2007, according to the Organic Trade Assn., an industry group.

But the truth is that, from a hard-nosed science point of view, it’s still unclear how much better — if at all — organic food is for one’s health than non-organically grown food.

“Organic” means food grown without most conventional pesticides or fertilizers made with synthetic ingredients, according to the U.S. Department of Agriculture’s website (usda.gov). To carry the “organic” seal, a product must be certified as having been produced according to federal regulations. Small farmers are exempt.

Prepared food made with organic ingredients also tends to be processed more gently, with fewer chemical additives, said Charles Benbrook, an agricultural economist who is chief scientist at the Organic Center. The nonprofit research group is based in Boulder, Colo., and is supported by the organic food industry.

But the word “organic” has not been designated as an official health claim by the government. Such a designation is used only when there is evidence of significant health benefits — and so far, that evidence is lacking for organic food.

It’s clear, however, that conventionally grown food has remnants of pesticides on it. A 2002 study in the journal Food Additives and Contaminants showed that there were more pesticide residues on conventional than organically grown food, even after the food was washed and prepared. There’s also clear evidence that pesticides can enter the body in other ways, a major reason that Environmental Protection Agency regulations exist to keep farm workers from entering recently sprayed fields.

A study by Emory University researchers and others published in 2006 in Environmental Health Perspectives, a peer-reviewed journal published by the National Institutes of Health, showed that when children were fed a conventional diet, their urine contained metabolic evidence of pesticide exposure, but that when they were switched to an organic diet, those signs of exposure disappeared.

All of which raises the question: How much harm do pesticides cause?

A number of studies suggest that, at high doses, organophosphate chemicals used in pesticides can cause acute poisoning and that even at somewhat lower doses, they may impair nervous system development in children and animals. But at the amounts allowed by the government in the American food supply? That’s where many nutritionists and environmental scientists seem to part company.

“We don’t have any good proof that there is any harm from fruits and vegetables grown with the pesticides currently used,” said Dr. George Blackburn, a nutritionist at Beth Israel Deaconess Medical Center in Boston and associate director of the Division of Nutrition at Harvard Medical School. The real issue is to get people to eat more fruits and vegetables, whether they’re grown conventionally or organically, he added.

“Keeping herbicide and pesticide levels as low as possible does make sense, although there is no clear evidence that these increase health risks at the levels consumed currently in the U.S.,” said Dr. Walter Willett, chairman of the department of nutrition at the Harvard School of Public Health.

What is of concern, he said, is the meat industry’s increasing use of growth hormones in animals. (The “organic” label on beef means, among other things, that the cattle it came from were raised without antibiotics and hormones. Some non-organic beef is also raised without hormones or antibiotics, as noted on its label.)

Even if we don’t yet have all the evidence that organic produce might be desirable, Benbrook of the Organic Center said it’s time to change the notion that there’s nothing wrong with a little pesticide for breakfast. Over the last two years, he said, “nearly every issue of Environmental Health Perspectives has had at least one new research report” on how pesticides can harm a child’s neurological growth, particularly on brain architecture, learning ability and markers for attention deficit hyperactivity disorder. While this falls short of incontrovertible proof that properly washed conventional produce can harm people, it does raise red flags, environmentalists say.

Weighing the value of organic foods also means looking at nutrition, not just the dangers of pesticides — and there is disagreement over whether organic food supplies more nutrients.

Researchers at UC Davis did a 10-year study, published last year, in which a particular strain of tomatoes was grown with pesticides on conventional soil right next to the same strain grown on soil that had been certified organic. All plants were subject to the same weather, irrigation and harvesting conditions.

The conclusion? Organic tomatoes had more vitamin C and health-promoting antioxidants, specifically flavonoids called quercetin and kaempferol — although researchers noted that year-to-year nutrient content can vary in both conventional and organic plants.

Other research has also shown nutritional advantages for organic food, according to the Organic Center, which reviewed 97 studies on comparative nutrition. Benbrook, the center’s chief scientist, says that although conventionally grown food tends to have more protein, organic food is about 25% higher in vitamin C and other antioxidants.

Yet a recent Danish study published in the Journal of the Science of Food and Agriculture showed no vitamin and mineral advantage to organic food.

So, what to eat? ………… Side with the nutritionists who urge people to eat more fruits and vegetables, regardless of how they’re grown. Common sense, though not necessarily science, would seem to favor organics, if you can afford them. But if you want, split the difference — buy organic for fruits and vegetables that are thin-skinned or hard to wash or peel, and go conventional for those, such as bananas, that peel easily.

Sources: Los Angles Times

Reblog this post [with Zemanta]
Categories
Featured

How to Prevent Back Pain at Work

[amazon_link asins=’B01H7SPVSS,B00D5J7SL2,B01L9OCCPG,B01MY18PG1,B077KM3H5J,B075TK4DM9,B00ZHTM1D8,B075B75GX3,B071HYLC77′ template=’ProductCarousel’ store=’finmeacur-20′ marketplace=’US’ link_id=’0e22a983-1713-11e8-874a-45735a2e4812′]

Simple, basic movements at your desk can lead to major back problems—unless you change a few habits.

You bend over to grab a folder from your filing cabinet and you feel it—a sudden flash of fiery pain that shoots through your spine. But while that motion may have set off the painful sensation, bending down was probably just the straw that broke the camel’s back, so to speak.

Day in and day out we treat our backs poorly, mostly with improper and repetitive movements. It only makes sense that a big part of the problem is how we move—and, more often, don’t move—at work, where most of us spend a major portion of our lives. Other factors play a role as well, such as the number and variety of manual tasks performed on the job, along with age, genetics, your schedule, desk setup and stress load. Experts say all these things combine to create unnecessary discomfort.

In Pictures: Preventing Back Pain at Work also Tips for Preventing Back Pain at Work:

“It’s important to know that aspects of the work environment can make things better or worse,” says Dr. Jeffrey Katz, associate professor of medicine and orthopedic surgery at Harvard Medical School, and author of the book Heal Your Aching Back.

A common problem

Back pain is a much more common problem than most people realize. Lower-back pain is cited as the number-two reason why Americans see their doctors, second only to colds and the flu. And patients suffering from backaches consume more than $90 billion annually in health care expenses, according to 2004 research from Duke University.

On the whole, up to 80 percent of people will deal with this health problem at some point in their life, Katz says. In an office setting of 100 people, he estimates that on a given day, 10 to 12 people probably have some kind of back pain.

Despite the prevalence of the problem, most people don’t put in the effort to examine and tweak their regular work habits to prevent it.

“People don’t take care of themselves until they’re in pain,” says Todd Langer, a Boulder, Colo.-based corrective exercise expert and creator of the P.A.S.T. Functional Fitness Method, which aims to relieve pain through unique balance-board-driven exercises.

Langer, who works with back pain sufferers at One Boulder Fitness Health Club, says the biggest mistake office workers make is continuing to sit in their desk chairs for hours on end. Sitting for sustained periods of time puts too much pressure on the discs and joints in your back.

To give your body a break, Langer suggests regularly moving your rear around in your chair and shifting your weight. If you spend a lot of time on the phone, stand up occasionally during conversations and try to take a short walk at least every half-hour, even if it’s just to the water cooler or printer. Use your e-mail to send yourself reminders until it becomes a habit.

It’s also a smart idea to examine your work station for potential causes of imbalances, says Stefan Aschan, owner and founder of Strength123, a provider of nutrition and fitness programs in New York City and online. Are the floors in your office uneven? Does your chair rest half on and half off a thick, plastic rug pad? Do you, as many men do, keep your wallet in your back pocket and sit on it all day long? Do you cradle the phone between your head and shoulder instead of wearing a headset?

If so, you may be changing the way your body weight is distributed on your discs, Aschan says. Over time, that pressure may cause a disc to bulge, which can be painful.

While you’re looking at your desk, check on the positioning of your chair, computer and phone. You may have heard this advice before, but following through is another story. Todd Sinett, owner of the New York-based Midtown Chiropractic Health and Wellness practice and author of The Truth About Back Pain, recommends asking your company for an adjustable chair that will help maintain the natural curves of your spine, supporting your lower back. (Placing a pillow behind you will also do the trick if your boss won’t spring for an ergonomic chair.)

Your feet should lightly rest on the floor or, if you’re short, on a footrest. You shouldn’t have to crane your neck forward, up or down to see your monitor, and you shouldn’t have to strain to reach your phone. The goal is to square yourself.

Emotional element:

Work-related stress can take its toll on your back too, Sinett says. While people manifest stress in different ways, it usually creates muscle tension. That constant contracting, over time, can cause muscle spasms and headaches—and possibly make you more vulnerable to injury.

If you’re too tired and stressed out after a long day of work to do anything but pass out on the couch, you could be compounding the problem, says Dr. Stephen Courtney, an orthopedic surgeon at Texas’ Baylor Regional Medical Center at Plano. Just as you should be stretching your muscles throughout the day, you should also be giving them a regular workout, either at the gym, on the court or in the yoga studio.

As with any change you make to your daily habits, there’s no guarantee an exercise regime will protect you from back problems. But it might decrease the frequency of recurrent episodes, according to Katz. For people in pain, it’s a move in the right direction.

Sources:msn health & fitness

Reblog this post [with Zemanta]
Categories
Featured

Acid Reflux Disease Hits Americans Hard

[amazon_link asins=’B002TC8CDO,0982708319,B076HLGRRP,1101905581,B01KKPKOFK,1942411154,B00E3X5K6Y,B00772AQD0,B00CZC2X3S’ template=’ProductCarousel’ store=’finmeacur-20′ marketplace=’US’ link_id=’c8206e89-f875-11e7-b486-25c913333e5e’]

Today, approximately 60% experience occasional episodes of acid reflux, and about 25% deal with the problem on a weekly basis. The prevalence of the condition in North America is increasing by about 5% a year, according to a 2007 study in the journal Clinical Gastroenterology and Hepatology.

A report in January from the Agency for Healthcare Research and Quality found that more than 95,000 people in the U.S. were hospitalized with acid reflux as a primary diagnosis in 2005, up 4.5% from 1998. But the number of people hospitalized with reflux as either a primary or secondary diagnosis reached 3 million in 2005 — an increase of 216% from 1998.

…………………………………...
As this old Alka-Seltzer commercial makes apparent, Americans have grappled with acid reflux for decades.

Gastroesophageal reflux disease, GERD or acid reflux, occurs when the small ring of muscle at the bottom of the esophagus weakens and allows stomach acid and food to back up, or reflux, into the esophagus after a meal. Common symptoms include heartburn, difficulty swallowing, an acidic taste in the mouth and nausea or vomiting.

The increase in obesity is speculated to be one cause of its growing prevalence. Excess fat in the abdominal area pushes on the stomach’s contents; stomach fat causes distention and relaxes the lower esophagus; and fat-laden foods slow down the stomach’s emptying process. Other factors include Americans’ notoriously poor nutritional habits and a heightened awareness of the condition induced by pharmaceutical advertising.

Medications also may be contributing to the problem.

“If people didn’t have good medications to treat it and something they ate made them sick, they would avoid it — but it’s human nature to pop a pill and continue eating,” said Dr. Prateek Sharma, a professor of medicine and director of the GI Fellowship Training at the University of Kansas School of Medicine.

Medical therapy:
Although medication is not a cure for acid reflux, a majority of patients find relief through prescription and over-the-counter drugs. Aside from traditional antacids, including Alka-Seltzer and Tums, there are now two main medications used to treat reflux.

H2 blockers reduce the amount of histamine-2, which produces acid in the stomach. They are recommended for people with less frequent and severe bouts of reflux. Zantac 75, Pepcid AC, Tagamet HB and Axid AR are some of the products available without a prescription.

A second medication is the proton pump inhibitor, which shuts down proton pumps in the stomach that produce acid. These are stronger than H2 blockers and recommended for people with more persistent, acute symptoms. Products such as Prilosec, Prevacid and Nexium are available only by prescription; Prilosec OTC is the only proton pump inhibitor available over the counter.

Even though there are a number of brands, Sharma said they all work similarly. He recommends patients use them for periodic acid reflux problems — once a week or twice a month.

There are some side effects associated with the medications, though most physicians say they are rare. Dr. Nicholas Shaheen, an associate professor of medicine and epidemiology and director of the Center for Esophageal Diseases and Swallowing at the University of North Carolina School of Medicine, said acid-suppressive medications are among the safest drugs he prescribes.

One potential issue is that stomach acid helps fight infection, so reducing acid could make individuals more prone to infections like pneumonia, said Dr. Stuart Spechler, chief of gastroenterology at the Dallas Veterans Affairs Medical Center and professor of medicine at the University of Texas Southwestern Medical Center at Dallas.

The medications also may block the absorption of vitamins and minerals such as B-12 and calcium, which could lead to hip fractures.

Surgical options:-For people who have responded to medication but continue to experience symptoms such as heartburn or regurgitation, surgery is an option. Only about 5% of reflux patients undergo the minimally invasive procedure in which the upper part of the stomach is wrapped around the lower esophagus to re-create the weakened valve.

Some doctors are skeptics of the surgery, Spechler included. He said the procedure tends to “break down” over time, and though many of his surgical patients tell him their symptoms are improved afterward, few are completely cured.

In the late 1980s, Spechler and his colleagues performed a study comparing the results of patients on medication and those receiving surgery. A follow-up study in 2001 found that almost two-thirds of the surgical patients were back on medication.

Dr. David Rattner, professor of surgery at Harvard Medical School and chief of gastroenterology and general surgery at Massachusetts General Hospital, said the surgery is relatively simple; most people go home after 24 hours and are “100%” after about two weeks. Side effects of surgery are rare. They include difficulty swallowing, excessive gas or return of symptoms, particularly among obese patients. Spechler said deaths occur in about one in every 1,000 operations.

One final way to treat reflux is through various endoscopic procedures, including stitching or using radio-frequency waves to restore the lower esophageal muscles. Studies have shown that these procedures can reduce medication usage, are relatively safe and can improve quality of life.

But they are not time-tested and not commonly used. In 2002, the American Gastroenterological Assn. said endoscopic treatment is not a recommended therapy for reflux sufferers.

Sources: health@latimes.com

Related articles by Zemanta
Reblog this post [with Zemanta]
Categories
News on Health & Science

Health Moves ‘Halve Early Deaths’

[amazon_link asins=’B00CZBZRK0,1544165374,0877900086,154309600X,0768407915,B013UGE132,B0106NXBYM,0997027509,1250121477′ template=’ProductCarousel’ store=’finmeacur-20′ marketplace=’US’ link_id=’cd7bb7b0-098f-11e7-8e3d-9751799b3852′]

Women could halve their risk of premature death by adopting a healthier lifestyle, research suggests…..
Smoking accounted for nearly a third of the deaths

By avoiding cigarettes, exercising regularly, eating healthily and keeping weight in check, 55% of early deaths from chronic diseases could be avoided.

Following all four lifestyle tips could cut 44% of cancer deaths and 72% of cardiovascular deaths, the study of nearly 80,000 nurses suggests.

The work is published on the British Medical Journal website.

In the 24-year study, 28% of the 8,882 deaths could be attributed to smoking and 55% to the combination of smoking, being overweight, not doing enough exercise and a poor diet.

Drinking too much alcohol also contributed, but women with “light-to-moderate” alcohol consumption of up to one drink a day were less likely to die from cardiovascular diseases than teetotallers.

Report author Dr Rob van Dam, from the Brigham and Women’s Hospital and Harvard Medical School, said the study’s positive findings on moderate consumption of alcohol should not encourage people to “go overboard”.

“It seems to be that drinking a little alcohol can lower the risk of heart disease, but you have to look at the overall picture too. We also saw in our study that people who drink a lot of alcohol have a higher risk of dying from cancer.”

He said it could be easy for people to adopt the basic lifestyle recommendations.

Simple advice

“In busy, modern life it’s more difficult to adapt to these factors, but people don’t have to spend hours lifting heavy weights.

“It’s simple dietary changes like eating more whole-grains and less red meat, walking to work and to the grocery shop, these really add up. And of course the thing to state is not to smoke.”

According to Dr van Dam, the recommendations in his study could apply to men as well as women.

The 77,782 women aged 34 to 59 who took part in the study completed detailed follow-up questionnaires every two years about their diet, frequency of physical activity, alcohol intake, weight, how much they smoked, and disease history.

Over the follow-up period the authors documented 8,882 deaths including 1,790 from heart disease and 4,527 from cancer.

A spokeswoman from the British Nutrition Foundation said: “This study reaffirms the importance of prevention.

“It is worth making lifestyle changes now, so that our later years are spent free from diseases such as cancer and heart disease.”

“It is worth making lifestyle changes now, so that our later years are spent free from diseases”.…as per British Nutrition Foundation spokeswoman

Risk reduction

Meanwhile, a study by the British Heart Foundation has found women at high risk of diabetes can reduce their body’s insulin resistance – the most important biological risk factor for diabetes – by exercising.

After seven weeks of an exercise programme of three 30 minute exercise sessions in the first week, working up to five 60 minute sessions in weeks six and seven, insulin resistance had reduced by 22% in women whose family history put them at a high risk of type 2 diabetes.

Professor Peter Weissberg, medical director at the BHF, said: “I hope the findings will encourage people to get active for their health.”

Sources: BBC NEWS:Sept. 16. ’08

Related articles by Zemanta
Reblog this post [with Zemanta]
Categories
News on Health & Science

Unravelling Alzheimer’s

[amazon_link asins=’1988298156,3639210980′ template=’ProductCarousel’ store=’finmeacur-20′ marketplace=’US’ link_id=’1a266f4b-c6eb-11e7-9384-af77c0736d47′]

Recent studies throw much light on changes in the brain that lead to Alzheimer’s disease.

CLICK & SEE

It may have been ascribed a name more than a century ago, but Alzheimer’s disease — the most common form of dementia that makes people forget names, places and things and lose track of time and events irretrievably — still remains a mystery.

Science has so far failed to fully understand the exact cause of this brain disorder, let alone develop a cure. Alzheimer’s strikes at old age, occasional memory lapse being the first symptom. The condition deteriorates rapidly and those suffering from its severest forms may not be able to recognise even their closest family members. Moreover, the patients often experience delusions and hallucinations.

The name “Alzheimer’s disease” entered the medical lexicon in 1907 following a description of the condition by the German physician Dr Alois Alzheimer at a scientific meeting the year before. Dr Alzheimer happened to treat a female patient in 1901 who had some peculiar symptoms: problems with memory, unfounded suspicions about her husband’s fidelity and difficulty in speaking and understanding what was said to her. After her death — which was about five years later — he performed an autopsy on her, of course with her family’s permission. He found that her brain had shrunken dramatically, particularly in the cortex region, the outer layer involved in memory, thinking, judgement and speech.

Scientists may still not know the cause of the disease, but recent advances in neuro-imaging techniques have shown that those suffering from it have two abnormal structures in their brain: plaques formed of deposits of a sticky protein fragment called beta-amyloid, and tangled or twisted fibres of another protein called tau inside the dying nerve cells.

Actually, most people develop plaques and tangles as they age, but those with Alzheimer’s tend to form them on a much larger scale. Ever since the discovery of these unusual elements in the brain of Alzheimer’s patients, scientists have been trying to ascertain their role in triggering as well as in the progression of the disease.

There have been three independent studies recently — two of them involving Indian researchers — that have greatly enhanced scientists’ understanding of Alzheimer’s.

The first, by a team of researchers that included Ganesh Shankar and Tapan Mehta of Harvard Medical School, shows that all the beta-amyloid in an Alzheimer’s patient’s brain is not directly responsible for the disease. The work, led by Dennis Selkoe of the Centre for Neurologic Diseases at Harvard, is the first such study to unlock the cascade of molecular events that lead to this debilitating condition. The team also has researchers from University College, Dublin, and the Royal College of Surgeons in Ireland.

Selkoe and his team observed for the first time that beta-amyloid exists in various forms. While some of these survive as single molecules called monomers, there are others which are formed by two or more molecules of beta-amyloid that stick together and which are soluble. Then there are clumps which are not soluble at all.

The study, recently published in Nature Medicine, came up with an interesting finding. The scientists first isolated beta-amyloid from the brains of Alzheimer’s patients, separating them as monomers, oligomers and insoluble plaque. They then injected these separately into the brains of mice. To their surprise they found that memory was impaired only when soluble beta-amyloid oligomers were administered to the hippocampus (brain region where memory is stored) of the animals.

The exposure to soluble beta-amyloid reduced the density of dendrite spines (that actually receive and transit messages sent by other brain cells) in the hippocampus by almost half. This led the scientists to conclude that soluble beta-amyloid molecules act directly on synapses, the connections between neurons that are necessary for communication in the brain.

When they exposed the mice nerve cells to amyloid plaques from which soluble beta-amyloid had been removed, the researchers found that there was no disturbance in the brain signalling.

“We think that plaques are protective, but it’s the soluble oligomers that interrupt synaptic function,” says Selkoe.

“The study has put yet one more piece into place in the puzzle that is Alzheimer’s,” observes Richard Hodes, director of the US National Institute on Aging that financed the study.

The second study, by Lawrence Rajendran, a post-doctoral student at the Max Planck Institute of Molecular Cell Biology and Genetics at Dresden in Germany, and colleagues looks into the very formation of beta-amyloid. Their work shows that beta-secretase, an enzyme that chops down a molecule called amyloid precursor protein to make beta-amyloid, works only in a tiny compartment inside the brain cell.

Beta-secretase, which is found in the cells of many organs, is an innocent bystander most of the time, Rajendran told KnowHow. “Only when it is inside the endosome — a tiny compartment in brain cells — does it assume a villainous form,” he says. He thinks that if scientists can devise a strategy to attack beta-secretase inside the endosomes, they can control the production of beta-amyloid.

Yet another study by researchers in the UK and Canada, which appeared last week in Nature Cell Biology, says that the best way to treat Alzheimer’s is to trick the brain into not producing the tau protein, which forms the aggregates called tangles. The scientists, who studied the chemistry and structure of the tau protein, designed an enzyme inhibitor which uses a sugar molecule to lower the production of the protein.

With the new insights, scientists hope that the management of Alzheimer’s disease — which is estimated to cost more than $300 billion a year — may become easier. Perhaps there may soon be drugs that can treat the worst of neuro degenerative disorders.

Sources: The Telegraph (Kolkata, India)

Related articles by Zemanta
css.php