Researchers Debunk Medical Myths About Vitamin D


We are constantly bombarded with conflicting headlines about nutrition and ads for products that promise to make or keep us healthy. Sorting out the truth from the hooey is an uphill battle, but science can help. A team of researchers have examined 10 common claims about vitamin D, and found that most of them lack evidence. They published their findings in the Journal of General Internal Medicine. 

Lead researcher Michael Allan is the director of Evidence-Based Medicine at the University of Alberta. He and his colleagues reviewed more than 80 studies on vitamin D, looking for support for claims that the vitamin can reduce cancer risk, treat arthritis, and more. The team was somewhat surprised by their results; "Even areas that we really thought there was good evidence for benefit early on, don't seem to be bearing out," Allan said in a press statement. In other words, we should rein in our enthusiasm for a "vitamin D panacea," as the authors call it. 

The results showed insufficient evidence for eight popular beliefs about vitamin D supplementation:

  • That it can treat depression;
  • That it can treat rheumatoid arthritis;
  • That it can treat multiple sclerosis;
  • That it can prevent respiratory tract infections;
  • That it lowers cancer risk and mortality;
  • That it reduces overall mortality;
  • That taking a higher dose is better; and
  • That healthy adults should get their vitamin D levels checked regularly.

The remaining two out of the ten beliefs tested were backed by some evidence. The researchers found that vitamin D supplementation can help reduce the risk of falls and the risk of fracture from falls in older people. But even those benefits are minimal, Allan says. 

“If you were to take a group of people who were at higher risk of breaking a boneso had about a 15 per cent chance of breaking a bone over the next 10 yearsand treated all of them with a reasonable dose of vitamin D for a decade, you'd prevent a fracture in around one in 50 of them over that time. Many people would say taking a drug for 10 years to stop one in every 50 fractures is probably not enough to be meaningful.” 

Now, just because something hasn’t been proved doesn’t mean it’s wrong. Allan says a lot of the existing vitamin D research was poorly done, and there hasn’t been much of it. It’s possible that, in the future, research will find enough evidence to support some of these claims. But right now, it just isn't there. 

For more myths and facts, check out the National Institutes of Health’s vitamin D web page.

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New Patient Test Could Suggest Whether Therapy or Meds Will Work Better for Anxiety

Like many psychological disorders, there's no one-size-fits-all treatment for patients with anxiety. Some might benefit from taking antidepressants, which boost mood-affecting brain chemicals called neurotransmitters. Others might respond better to therapy, and particularly a form called cognitive behavioral therapy, or CBT.

Figuring out which form of treatment works best often requires months of trial and error. But experts may have developed a quick clinical test to expedite this process, suggests a new study published in the journal Neuropsychopharmacology.

Researchers at the University of Illinois at Chicago have noted that patients with higher levels of anxiety exhibit more electrical activity in their brains when they make a mistake. They call this phenomenon error-related negativity, or ERN, and measure it using electroencephalography (EEG), a test that records the brain's electric signals.

“People with anxiety disorders tend to show an exaggerated neural response to their own mistakes,” the paper’s lead author, UIC psychiatrist Stephanie Gorka, said in a news release. “This is a biological internal alarm that tells you that you've made a mistake and that you should modify your behavior to prevent making the same mistake again. It is useful in helping people adapt, but for those with anxiety, this alarm is much, much louder.”

Gorka and her colleagues wanted to know whether individual differences in ERN could predict treatment outcomes, so they recruited 60 adult volunteers with various types of anxiety disorders. Also involved was a control group of 26 participants with no history of psychological disorders.

Psychiatrists gauged subjects’ baseline ERN levels by having them wear an EEG cap while performing tricky computer tasks. Ultimately, they all made mistakes thanks to the game's challenging nature. Then, randomized subjects with anxiety disorders were instructed to take an SSRI antidepressant every day for three months, or receive weekly cognitive behavioral therapy for the same duration. (Cognitive behavioral therapy is a type of evidence-based talk therapy that forces patients to challenge maladaptive thoughts and develop coping mechanisms to modify their emotions and behavior.)

After three months, the study's patients took the same computer test while wearing EEG caps. Researchers found that those who'd exhibited higher ERN levels at the study's beginning had reduced anxiety levels if they'd been treated with CBT compared to those treated with medication. This might be because the structured form of therapy is all about changing behavior: Those with enhanced ERN might be more receptive to CBT than other patients, as they're already preoccupied with the way they act.

EEG equipment sounds high-tech, but it's relatively cheap and easy to access. Thanks to its availability, UIC psychiatrists think their anxiety test could easily be used in doctors’ offices to measure ERN before determining a course of treatment.

A Pitless Avocado Wants to Keep You Safe From the Dreaded 'Avocado Hand'

The humble avocado is a deceptively dangerous fruit. Some emergency room doctors have recently reported an uptick in a certain kind of injury—“avocado hand,” a knife injury caused by clumsily trying to get the pit out of an avocado with a knife. There are ways to safely pit an avocado (including the ones likely taught in your local knife skills class, or simply using a spoon), but there’s also another option. You could just buy one that doesn’t have a pit at all, as The Telegraph reports.

British retailer Marks & Spencer has started selling cocktail avocados, a skinny, almost zucchini-like type of avocado that doesn’t have a seed inside. Grown in Spain, they’re hard to find in stores (Marks & Spencer seems to be the only place in the UK to have them), and are only available during the month of December.

The avocados aren’t genetically modified, according to The Independent. They grow naturally from an unpollinated avocado blossom, and their growth is stunted by the lack of seed. Though you may not be able to find them in your local grocery, these “avocaditos” can grow wherever regular-sized Fuerte avocados grow, including Mexico and California, and some specialty producers already sell them in the U.S. Despite the elongated shape, they taste pretty much like any other avocado. But you don’t really need a knife to eat them, since the skin is edible, too.

If you insist on taking your life in your hand and pitting your own full-sized avocado, click here to let us guide you through the process. No one wants to go to the ER over a salad topping, no matter how delicious. Safety first!

[h/t The Telegraph]


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