Teens who smoke pot can damage memory, intelligence

AppId is over the quota
AppId is over the quota

LONDON (Reuters) - Teenagers who become hooked on cannabis before they reach 18 may be causing lasting damage to their intelligence, memory and attention, according to the results of a large, long-term study published on Monday.

Researchers from Britain and the United States found that persistent and dependent use of cannabis before the age of 18 may have a so-called neurotoxic effect, but heavy pot use after 18 appears to be less damaging to the brain.

Terrie Moffitt, a psychology and neuroscience professor at King's College London's Institute of Psychiatry, said the scope and length of the study, which involved more than 1,000 people followed over 40 years, gave its findings added weight.

"It's such a special study that I'm fairly confident cannabis is safe for over-18 brains, but risky for under-18 brains," she said.

Before the age of 18, the brain is still being organized and remodeled to become more efficient and may be more vulnerable to damage from drugs, she added.

Moffitt worked with Madeleine Meier, a post-doctoral researcher at Duke University in the United States, to analyze data on 1,037 New Zealanders who took part in the study. About 96 percent of the original participants stuck with the study from 1972 to today, she said.

At age 38, all participants were given a battery of psychological tests to assess their memory, processing speed, reasoning and visual processing.

Those who had used pot persistently as teens scored significantly worse in most of the tests. Friends and relatives regularly interviewed as part of the study were more likely to report that the heavy cannabis users had attention and memory problems such as losing focus and forgetting to do tasks.

The researchers also found that people who started using cannabis in adolescence and continued for years afterwards showed an average decline in Intelligence Quotient (IQ) test scores of eight points between the ages of 13 and 38.

"Study subjects who didn't take up pot until they were adults with fully-formed brains did not show similar mental declines," Moffitt said.

"MARIJUANA IS NOT HARMLESS"

She said the decline in IQ could not be explained by alcohol or other drug use or by having less education, and Meier said the key variable was the age people began to use pot.

Meier said the study's message was clear: "Marijuana is not harmless, particularly for adolescents."

While eight IQ points may not sound like a lot on a scale where 100 is the mean, Meier said an IQ drop from 100 to 92 would mean dropping from being in the 50th percentile to being in the 29th.

Higher IQs also correlate with higher levels of education and income, better health and longer lives, she said. "Somebody who loses eight IQ points as an adolescent may be disadvantaged ... for years to come," she added.

Robin Murray, a professor of psychiatric research at King's Institute of Psychiatry, who was not involved in this work, said the study was impressive and the findings should be taken "very seriously".

"It is of course part of folk-lore among young people that some heavy users of cannabis seem to gradually lose their abilities and end up achieving much less than one would have anticipated," he said in a statement. "This study provides one explanation as to why this might be the case."

Previous research on cannabis use has also pointed to potential long-term psychiatric effects.

A study published in March last year found that people who use it a lot in their youth dramatically increase their risk of psychotic symptoms, and that continued use of the drug can increase the risk of developing a psychotic disorder.

Meier pointed out that it was not possible to say from this latest study what a safer age for persistent pot use might be, or what kind of dosage level causes damage.

According to the 2011 United Nations Office for Drugs and Crime (UNODC) global drugs report, which used data from 2009, between 2.8 and 4.5 percent of the world's population aged 15 to 64 - or between 125 and 203 million people - had used cannabis at least once in the previous 12 months.

SOURCE: http://bit.ly/NS97zV Proceedings of the National Academy of Sciences, online August 27, 2012.

Organic Foods Not Necessarily Better

Study Questions Health Benefits of Eating Organic

Sept. 4, 2012 -- Will eating pricey organic foods make you healthier? Maybe not, a new research review shows.

The review sums up evidence from hundreds of studies of organic foods. It's published in the Annals of Internal Medicine.

Some of the studies compared organic milk, meats, eggs, and produce to non-organic foods. Those studies measured nutrients in the foods as well as contaminants like pesticides and bacteria. A few studies tried to find health differences between people who ate only organic or only non-organic foods.

After weighing all the evidence, the researchers conclude that organic foods don't appear to have more vitamins or nutrients than non-organic foods.

Non-organic fruits and vegetables were 30% more likely to have pesticides than organic fruits and vegetables. But because it's rare for any produce to exceed pesticide safety limits set by the FDA, researchers say it's not known whether reducing an already small exposure makes a difference.

The review also shows that organic meats are less likely to harbor "superbug" bacteria that are resistant to treatment with antibiotics. But researchers say most antibiotic-resistant infections in people come from misuse of antibiotics, not from eating contaminated foods.

In the end, researchers say there's no evidence that people who stick to organic diets are healthier than people who eat non-organic foods.

Not everyone agrees.

"There are many different reasons why people choose organic. They may be concerned about animal welfare or the environment. They may do it for taste," says researcher Crystal Smith-Spangler, MD, of Stanford University in California. "I didn't find that nutrition is a major reason to choose organic foods."

Nutrition experts praised the research since it helps to dispel some myths that might make people afraid to eat fresh fruits and vegetables.

"When we're talking about organic, it's really the process, not the product. The process of organic farming is different than conventional farming, but that doesn't mean that the food is bad or unsafe," says Melissa Joy Dobbins, RD, MS, a spokeswoman for the Academy of Nutrition and Dietetics.

Dobbins points out that organic foods can cost twice as much as non-organic foods.

"I don't want that mom who's at the grocery store to feel guilty if she can't afford organic. That mom shouldn't feel like she's making a lesser choice," Dobbins says.

Other experts, however, called the new review misleading.

"The message the general public is going to get is that there are no health benefits from organic foods so why seek it out? Why pay a slightly higher price? I do think the science and facts support some very significant and important long-term benefits," says Charles Benbrook, PhD, a professor of agriculture at Washington State University in Pullman, Wash.

Benbrook points to a similar review published last year that reached the opposite conclusion. That study, by British researchers, found that organic fruits and vegetables contain about 12% more disease-fighting nutrients than non-organic foods. Sticking with organic produce, researchers concluded, would be the equivalent of eating 12% more regular fruits and veggies.

Other experts say the study's conclusions shouldn't change the major reasons that people choose organic foods.

"Nutrition is a lesser concern. It's not the main reason people are buying organic. If you eat organic food, you still need to eat a varied diet, it's not going to solve every health woe. It's marketed to be pesticide-free and antibiotic-free, and that was strongly supported by the study," says Sonya Lunder, MPH, a senior analyst with the nonprofit Environmental Working Group.

New book of cuisine exalts the power of plants

text is null
Parameter name: text

Ginkgo Biloba Doesn't Protect From Alzheimer's

Second Major Study Shows No Benefit to Supplement

Sept. 5, 2012 -- A second large study failed to show that the supplement ginkgo biloba can prevent Alzheimer's disease.

The study included close to 3,000 elderly people in France with memory problems. Some of them took ginkgo biloba and some did not.

Over five years of follow-up, about the same number of people in the two groups got Alzheimer's disease.

The study is published in the journal Lancet Neurology.

An earlier study followed people in the U.S. for an average of six years. It also found no evidence that ginkgo biloba prevents Alzheimer's disease or delays mental problems.

Ginkgo biloba is widely used and marketed as a memory-boosting drug. Alzheimer's researcher Lon Schneider, MD, says it shouldn't be.

He says close to 10,000 people have participated in studies examining ginkgo biloba's impact on memory and the brain.

"This supplement has been studied as extensively as any drug, with no evidence that it improves memory" or delays problems with thinking, Schneider says. He says if ginkgo biloba were being developed as a drug, it would have been abandoned long ago.

"The drug company response would probably be, 'We're not wasting another dime on this dog,'" he says.

The French study included people in their 70s and older. They had complained to their doctors of having problems with memory.

Half of the people took ginkgo biloba twice a day. The other half took identical-looking placebo pills.

Over the next five years, 4% of the ginkgo biloba group and 5% of the placebo group were diagnosed with Alzheimer's disease.

In a written statement, study researcher Bruno Vellas of Toulouse, France's Hopital Casselardit called for more studies on whether taking ginkgo biloba over the long term affects age-related memory decline.

"The fact that prevalence of [Alzheimer's disease] is expected to quadruple by 2050 suggests that research into preventative therapies for this disease needs to receive urgent attention," he says in the statement.

But Schneider says investigators would be better off looking elsewhere for effective treatments.

"If there were truly nothing else that might delay the onset of dementia I could understand why users might want to stick with ginkgo biloba," he says. "But we are learning about more and more health behaviors that appear to impact risk."

Studies suggest that getting regular exercise, eating less fat, and treating high blood pressure, high cholesterol, and other heart risk factors all protect against age-related memory decline, he says.

Vitamin d supplements may not improve heart health

by Genevra Pittman, updated 4 September 2012

NEW YORK (Reuters Health) - despite numerous studies linking higher levels of blood vitamin d heart attacks and deaths, a new trial found giving daily older women of d supplementation did not cut heart risk.

Women's cholesterol, blood pressure and blood glucose was not lower after one year to take one of the two doses of vitamin D than those who took placebo free of vitamin pills.

What is called observational studies, which measure vitamin d in the blood of the people and then follow them over time - tend to find a link between heart health and vitamin levels.

"There is a tremendous amount of epidemiological data showing a relationship between low levels of vitamin d and an increased risk of cardiovascular events," said Dr. Michel Chonchol, who studied this association at the University of Colorado Denver, but was not involved in the new research.

But these types of testing can prove the cause-effect because it is impossible to take into account all possible food and lifestyle differences between people with lower and higher vitamin D levels.

Randomised controlled trials, regarded as the "gold standard" studies of medicine, were designed to circumvent this obstacle. By dividing a group of people at random and give some but not for others a special treatment, researchers can better hone in on its specific effects.

For new trial, Adrian Wood of the University of Aberdeen in Britain and colleagues divided 305 sixties women into three groups. Every morning for a year, the women took either 400 units International (UI) or 1000 IU of vitamin d or a placebo.

Participants were returned to the laboratory every two months for a panel of heart tests.

In the study, women in each group were similar on most measures of health. Women in the placebo group, for example, had 152 pounds in weight, blood pressure and total cholesterol of 128/78 of 238.

The next year, cholesterol levels and blood pressure vary according to the season - but not based on knowledge if the women were taking additional vitamin d.

Ultimately, no there was no clear difference between the three groups of changes in cardiac markers, the wood team reported in the Journal of the clinical endocrinology & metabolism.

The study did not look far enough or have enough women, to determine if vitamin d could affect heart attack or death.

Food sources of vitamin d are cod liver oil and other fish and fortified juices and dairy products.

The Institute of Medicine recommends that most adults is 600 IU of vitamin d per day. In a report of 2010, he found there is strong evidence linking vitamin d and calcium for a better bone health but that the other benefits offered, including blood pressure and cardiovascular disease are provided.

However, some researchers believe taking additional vitamin D - especially for people who have very low levels first - can help prevent inflammation of the body and to play a role in the regulation of blood sugar.

SOURCE: http://bit.ly/ODc3xc Journal of Clinical Endocrinology & metabolism, August 3, 2012 online.

You forgot your password? Click here!

Beyond Statistics: 2 Faces of West Nile Virus

Thousands Now Live With West Nile Virus Infection. Here, 2 Share Their Stories

Aug. 31, 2012 -- This year, more than 1,500 people in the U.S. have been diagnosed with West Nile virus infection and several have died.

Transmitted by the bite of a mosquito, the infection isn't equal opportunity.

© 2012 WebMD, LLC. All rights reserved.

Some infected people don't notice any symptoms. Others have a milder form of the disease, known as West Nile fever. About 1 in 150 people infected develop severe complications, including infections of the brain (encephalitis) or spinal cord and connecting nerves (meningitis) or paralysis.

Rob Wagner Jr., 52, is a construction worker in Riverside County, Calif., near Los Angeles. He learned he had West Nile virus earlier this month.

Don R. Read, MD, is a Dallas surgeon who became infected in 2005 at age 63. He says he is still coming back from the complications, including paralysis.

Rob Wagner Jr., is a big guy who has worked construction most of his life. Most recently, he has been working as a glass glazer in Southern California.

In early August, he was hanging out at a friend's house in the city of Riverside, spending a lot of time in the backyard.

A lifelong mosquito magnet, he remembers being bitten but not thinking much about it. "I was getting bitten every night," he says.

One morning soon after, he woke up with a burning fever. "I was sweating like crazy," he says. The day before, he remembers feeling like he was coming down with something.

He was lagging at work. "I have to deal with measurements, stuff like that," Wagner says. "I was really slow, feeling incompetent in my measurements."

He had an excruciating headache. He says he's had those before, and they were linked with his high blood pressure. "It was like flu symptoms," he says.

"I had a friend take me to the emergency room." They told him the fever was 105 degrees.

"They started doing tests, taking blood. They did CT scans and MRI." He had two painful spinal taps, a typical test to check for meningitis, which doctors suspected.

Doctors admitted him to the hospital. They decided the diagnosis was bacterial meningitis and started him on antibiotics.

The pain was so bad the doctors put him on morphine.

The week he spent in the hospital was a nightmare, his sister, Pamela Vest, says. "A whole week, we couldn't even talk to him because he was so out of it."

"One morning he woke up crying," she says, "saying, 'What is wrong with me?' 'What is it?'"

When he improved some, he was released.

Then came the call from the Riverside County Department of Health. "It wasn't bacterial meningitis, it was West Nile virus," he says.

"I didn't know that much about it," he says. "I was still kind of out of it."

Non-Alcoholic Red Wine May Boost Heart Health

Sept. 6, 2012 -- Much research has touted the health benefits that come from drinking moderate amounts of red wine.

Now, a new study may extend some of these benefits to teetotalers. Non-alcoholic red wine may be even more effective at lowering blood pressure in men who are high risk for heart attack. The study findings appear in Circulation Research.

The study included 67 men who had diabetes or three or more heart disease risk factors. When the men drank red wine with alcohol, their blood pressure went down a little, and there was no change in blood pressure levels when they drank gin.

When the men drank non-alcoholic red wine, their blood pressure went down enough to lower their risk of heart disease by 14% and stroke by as much as 20%.

The real health benefits in red wine may be found in powerful antioxidants called polyphenols, not the alcohol. In fact, the alcohol in red wine may dampen its blood pressure-lowering potential. In the study, the red wine with alcohol and non-alcoholic wine contained equal amounts of polyphenols.

The researchers were able to link polyphenol levels to a boost in men’s levels of nitric oxide, which helps lower blood pressure. Nitric oxide helps blood vessels relax and allows more blood to reach your heart and organs.

During the study, the men ate similar diets and drank either 10 ounces of red wine, 10 ounces of non-alcoholic red wine, or 3 ounces of gin. All of the men tried each diet/beverage combination for four weeks.

“The non-alcoholic part of the wine -- namely polyphenols -- exert a protective effect on the cardiovascular system,” says researcher Ramon Estruch, MD, PhD of the University of Barcelona in Barcelona, Spain. “Polyphenols also have anti-inflammatory and antioxidant properties that may be useful to prevent other disease such as diabetes."

He predicts that more people will turn to non-alcoholic wine in the future. 

This is welcome news for people who can’t or don’t want to drink alcohol, says Suzanne Steinbaum, DO, at Lenox Hill Hospital in New York City. Although some alcohol is thought to be good for you, too much alcohol can increase blood pressure levels.  

“Certain people don’t want to drink alcohol, so here we have an alternative way for them to get the heart health benefits,” she says. “It’s not so much the alcohol as it is the polyphenols in red wine.”

Other alcoholic drinks have also been shown to have health benefits, but they may do so differently than red wine, Steinbaum says.