Archive for June, 2012
Can taking vitamin D and calcium help you live longer?
By Susan E. Matthews
Older people who take vitamin D supplements along with calcium may live longer than others, according to a new review of previous studies.
The researchers looked at data regarding the vitamin D intake of more than 70,000 adults in their 60s and 70s. They found that people who took vitamin D, along with calcium supplements, were 9 percent less likely to die over a three-year period, compared with people who took neither supplement.
However, they found that taking vitamin D alone had no effect on mortality rates.
For every 151 people who took with daily vitamin D and calcium for three years, one life would be spared, according to the researchers’ calculations.
The finding comes on the heels of several studies with conflicting results about the health benefits of vitamin D, including its possible effects on longevity. The new review is the largest of its kind, and included eight randomized controlled trials, said study leader Lars Rejnmark, of Aarhus University Hospital in Denmark. Such trials are considered the strongest type of scientific evidence.
Study participants were generally older people with health conditions, and possibly had inadequate nutrition. Therefore, it’s “not guaranteed that anyone in good health who takes these vitamins would increase life expectancy,” Autier said.
In the review, the researchers found that 5.5 percent of the 35,412 people who didn’t take vitamin D or calcium died during the study period, whereas 5.3 percent of the 35,116 people who took vitamin D died.
Taking vitamin D, with or without calcium, had a significant effect on mortality rates only after three years; mortality rates were not significantly different among those taking the vitamin after one or two years, according to the study.
Vitamin D and calcium are important throughout life, because of their role in bone health, Rejnmark said. But he recommends people start paying particular attention to their intake “around menopause for women, and around the age of 50 for men.”
While the review was based on studies of people who took supplements, Rejnmark said he does not believe the benefits would be any different for people who get the nutrients through food.
Autier noted that the greatest source of vitamin D is what the skin makes naturally when it is exposed to sunlight. People with darker skin tones, who are less able to produce vitamin D in response to sunlight, should consider supplements as a viable option, he said.
A total of 87 percent of the studies’ participants were female, but Rejnmark said this had no bearing on the results, and vitamin D and calcium are equally beneficial to both sexes in terms of preserving longevity.
More from MyHealthNewsDaily:
9 Good Sources of Disease-Fighter Vitamin D
8 Tips for Healthy Aging
7 Common Summer Health Concerns
5 mind-bending facts about dreams
By Jeanna Bryner
When your head hits the pillow, for many it’s lights out for the conscious part of you. But the cells firing in your brain are very much awake, sparking enough energy to produce the sometimes vivid and sometimes downright haunted dreams that take place during the rapid-eye-movement stage of your sleep.
Why do some people have nightmares while others really spend their nights in bliss? Like sleep, dreams are mysterious phenomena. But as scientists are able to probe deeper into our minds, they are finding some of those answers.
Here’s some of what we know about what goes on in dreamland.
1. Violent dreams can be a warning sign
As if nightmares weren’t bad enough, a rare sleep disorder — called REM sleep behavior disorder — causes people to act out their dreams, sometimes with violent thrashes, kicks and screams. Such violent dreams may be an early sign of brain disorders down the line, including Parkinson’s disease and dementia, according to research published online July 28, 2010, in the journal Neurology. The results suggest the incipient stages of these neurodegenerative disorders might begin decades before a person, or doctor, knows it.
2. Night owls have more nightmares
Staying up late has its perks, but whimsical dreaming is not one of them. Research published in 2011 in the journal Sleep and Biological Rhythms, revealed that night owls are more likely than their early-bird counterparts to experience nightmares.
In the study 264 university students rated how often they experienced nightmares on a scale from 0 to 4, never to always, respectively. The stay-up-late types scored, on average, a 2.10, compared with the morning types who averaged a 1.23. The researchers said the difference was a significant one, however, they aren’t sure what’s causing a link between sleep habits and nightmares. Among their ideas is the stress hormone cortisol, which peaks in the morning right before we wake up, a time when people are more prone to be in REM, or dream, sleep. If you’re still sleeping at that time, the cortisol rise could trigger vivid dreams or nightmares, the researchers speculate. [ Top 10 Spooky Sleep Disorders ]
3. Men dream about sex
As in their wake hours, men also dream about sex more than women do. And comparing notes in the morning may not be a turn-on for either guys or gals, as women are more likely to have experienced nightmares, suggests doctoral research reported in 2009 by psychologist Jennie Parker of the University of the West of England.
She found women’s dreams/nightmares could be grouped into three categories: fearful dreams (being chased or having their life threatened); dreams involving the loss of a loved one; or confused dreams.
4. You can control your dreams
If you’re interested in lucid dreaming, you may want to take up video gaming. The link? Both represent alternate realities, said Jayne Gackenbach, a psychologist at Grant MacEwan University in Canada.
“If you’re spending hours a day in a virtual reality, if nothing else it’s practice,” Gackenbach told LiveScience in 2010. “Gamers are used to controlling their game environments, so that can translate into dreams.” Her past research has shown that people who frequently play video games are more likely than non-gamers to have lucid dreams where they view themselves from outside their bodies; they were also better able to influence their dream worlds, as if controlling a video-game character.
That level of control may also help gamers turn a bloodcurdling nightmare into a carefree dream, she found in a 2008 study. This ability could help war veterans suffering from post-traumatic stress disorder (PTSD), Gackenbach reasoned.
5. Why we dream
Scientists have long wondered why we dream, with answers ranging from Sigmund Freud’s idea that dreams fulfill our wishes to the speculation that these wistful journeys are just a side effect of rapid-eye-movement (REM) sleep. Turns out, at least part of the reason may be critical thinking, suggests Harvard psychologist Deirdre Barrett who presented her theory in 2010 at the Association for Psychological Science meeting in Boston.
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Her research revealed that our slumbering hours may help us solve puzzles that have plagued us during daylight hours. The visual and often illogical aspects of dreams make them perfect for the out-of-the-box thinking that is necessary to solve some problems, she speculates.
So while dreams may have originally evolved for another purpose, they have likely been refined over time for multiple tasks, including helping the brain reboot and helping us solve problems, she said.
- 5 Mind-Bending Facts About Dreams (mytechnologyworld9.blogspot.com)
- 5 mind-bending facts about dreams (psychieblog.wordpress.com)
- Violent Dreams Can Be A Warning Sign (businessinsider.com)
- 5 mind-bending facts about dreams (purestrange.wordpress.com)
- Sleeper Sell! No Rest for City’s Techies as ‘Lucid Dreaming’ Gets Trendy (betabeat.com)
The findings show that girls tend to initiate the transition to a mixed-gender friendship network earlier than boys, and continue this transition at a faster pace during adolescence. As a result girls who experienced this transition early and fast were more likely to develop substance abuse problems during late adolescence.
Researchers followed a sample of almost 400 adolescents (58% girls), aged twelve to eighteen, from a large French-speaking school district in Canada. They were interviewed annually over a seven-year period about their friendship network and their use of alcohol and drugs.
Lead author Dr. François Poulin, “Peer relationships are considered to be one of the main risk factors for substance use. However, for boys, the formation of other-sex friendships is not associated with later substance use problems. Boys reported receiving higher levels of emotional support from their other-sex friends, whereas girls receive more support from their same-sex friends. It is possible that having other-sex friends is protective for boys because they gain emotional support and are therefore less likely to engage in problem behavior.”
The study finds that among girls, antisocial behavior and early pubertal maturation accelerated the increase in the proportion of other-sex friends. Compared to their same-sex friends, girls tended to form friendships with older males in out-of-school contexts. Since the legal drinking age is 18 in Canada, it may simply be more difficult for younger girls to purchase their own alcohol, thus older boys become one point of access for this substance. The study findings imply that parents may wish to take a more active role in monitoring their daughters’ friendships, especially with older boys.
The authors maintain that by middle adolescence, once this transition has been completed, the impact of other-sex friendships on girls’ maladjustment fades away. Mixed-gender networks then become more normative and girls are more likely to form romantic relationships with their male peers. The influence of boys on girls’ substance-using behavior might then operate in the context of these romantic relationships.
The authors suggest that future studies should also examine the longitudinal associations between other-sex friends and other outcomes such as educational achievement and antisocial behavior. Finally, aspects of these other-sex friendships in early adolescence should be more carefully investigated, including the setting in which they take place, their linkages with the rest of the youth’s friendship network, and parental supervision of these new emerging relationships