Friday, January 27, 2017

New Guidelines for the Prevention of Peanut Allergy

An expert panel of scientists meeting under the sponsorship of the National Institute of Allergy and Infectious Diseases has issued new guidelines for the prevention of peanut allergies in young children. The guidelines draw on findings published last year (see this blog, Mar. 9, 2015) which showed that adding peanut proteins to the diet of young children at risk for developing allergies significantly reduced the chances of those children developing peanut allergies by age five. The new guidelines are that infants can be fed peanut-containing foods at any age; as early as they begin taking solid food, in fact.

Some parents are skeptical, and a few are even angry. That's because the previous guidelines were to withhold peanuts from young children in the hope that sensitivity to peanuts could be avoided. According to these parents, this reversal of the guidelines is just more evidence that scientists (and their recommendations) shouldn't be trusted.

But the reality is that we try to make rational choices based on whatever information we have at the time. So when new and better information becomes available (such as the data published last year), we should look carefully at it and change our view, if warranted. In a nutshell (no pun intended) that is what has happened with the peanut recommendations.

Tuesday, January 24, 2017

2016 was the Hottest Year on Record

2016 was the hottest year on record and the third consecutive year of record temperatures, according to climate scientists.   Furthermore, the rate of temperature change seems to be accelerating.

Nearly all climate models conclude that the most likely cause of global warming is rising levels of atmospheric CO2 levels brought about by the burning of fossil fuels.  And yet, so far not much has been done about it.  The problem (and perhaps the reason that climate deniers continue to deny that global warming is even happening) is that curbing future increases in CO2 will not be easy or cheap as long as we continue to depend on fossil fuels for most of our energy needs.

And so Earth will probably continue to warm up.  Sigh.

Sunday, January 15, 2017

Should "Gene Editing" be Regulated?

The generally accepted definition if a GMO (genetically modified organism) is an organism whose genome has been modified by the addition of one or more genes from another species.  Most genetically modified corn, for example, has been modified by the addition of genes from certain bacteria, with the goal of giving the corn either resistance to insect pests or resistance to a common herbicide.  Not everyone thinks that GMOs are a good idea, and there have been numerous efforts (some successful, some not) to block their development and widespread use.

Now for a new but related question; how should we feel about "gene editing"; the simple removal of existing genes from an organism, without the addition of foreign genes?  It's now possible, due to a recently developed technique (called Crispr) for selectively snipping genes out of DNA at selected locations.  Crispr is already being used to produce gene-edited plants of interest, such as potatoes or mushrooms that don't turn brown and soybeans with healthier fatty acids.

Last year Congress passed a law requiring that foods containing GMO ingredients must be labeled as such.  However, that labeling requirement apparently doesn't extend to plants that are just gene-edited because currently they fall outside the regulatory authority of the federal agencies that oversee GMOs, such as the Agriculture Department and the Food and Drug Administration.

It'll be interesting to see whether the regulatory agencies ever decide to examine and/or regulate gene editing.

Friday, January 13, 2017

Does Prevagen Improve Memory?

You've seen the commercials for Prevagen, right? It's a dietary supplement containing a protein derived from jellyfish that (according to the manufacturer) "improves memory and reduces common cognitive problems associated with aging." Trouble is, those claims are bogus, according to both the Federal Trade Commission (FTC) and the New York Attorney General's office. This week the two agencies sued Prevagen's manufacturer, Quincy Bioscience for making false and misleading claims, most notably the claim that Prevagen has been "clinically proven" to work. According to the complaint, the experiments undertaken to prove Prevagen's effectiveness were scientifically invalid because they did not show that Prevagen worked any better than a placebo.

No big deal, you say? Well, if you give people memory tests over time, you'd expect some improvement just from test familiarity alone. That's why it's so important to compare the experimental (Prevagen) group to a control group (a group given a fake pill, or placebo), using valid statistical methods.

Prevagen can cost upwards of $60 for a 30-pill bottle. According to the FTC, about $165 million a year is spent on the supplement. That's a lot for an untested cure.

Quincy Bioscience has responded to the lawsuit with a statement that says, in part, that Prevagen hasn't been shown to harm anyone (which is beside the point), and that "hundreds of thousands" of people tell them that Prevagen works and improves their lives. The latter statement, of course, is unscientific and unverifiable.

Monday, January 9, 2017

A Hallucinogen Reduces Anxiety and Depression in Cancer Patients

Two well designed studies published simultaneously by research teams at New York University and Johns Hopkins University have both come to the same conclusion: that a single dose of a powerful hallucinogen reduces anxiety and depression in patients with life-threatening cancers. The hallucinogen, known as psilocybin, is the active ingredient in "magic mushrooms". Nearly 80% of the patients reported feeling better following their hallucinogenic experience. The most striking finding was that they felt better for a long time - more than six months, in fact.

The federal government doesn't allow the use of public funds for research into the possible therapeutic uses of criminalized drugs. However, the research itself isn't banned. The present studies were funded largely from private sources after careful review by university research panels and federal regulators.

No one is suggesting that psilocybin should be made widely available to cancer patients. Nor is anyone suggesting (yet) that psilocybin should be used to treat general anxiety and depression. Still, the very long-lasting effect on anxiety and depression of a single hallucinogenic dose of psilocybin is intriguing. We need to know more about how this hallucinogen works. What if, for example a closely related drug could be found that reduces anxiety and depression, without the initial hallucinogenic effect?  Now, that would be a blockbuster drug.

Thursday, January 5, 2017

Taking Fish Oils During Late Pregnancy Reduces Childhood Asthma

A Danish study reports that children whose mothers who took high doses of fish oils during the last three months of pregnancy were about 30% less likely to develop asthma by age three.  16.9% of children of mothers who took fish-oil capsules developed asthma by age three, compared to 23.7% of children of mothers who took placebo capsules containing olive oil.

What on earth prompted the researchers to even think of such an experiment?  It turns out that there was some logic behind it.   Two relevant facts are; 1) chronic inflammation in the lungs and airways contribute to the development of asthma, and 2) the fatty acids in fish oils are known to reduce inflammation.  Put these two together, and the experiment seemed like a good idea.

The researchers say it's too early to recommend that all pregnant women take fish-oil capsules during pregnancy.  For one thing, the doses used in this experiment were high; 2.4 grams 0f fish-oil per day, or about 15-20 times the amount found in a normal U.S. diet.  It's not known whether lower doses might be just as effective.  Nor is it known whether the results would be better (or worse) if the women had taken the fish oils throughout pregnancy, instead of just in the last trimester.

Also, consider this: the beneficial effects of fish-oils on asthma were demonstrated only because the researchers were looking for an effect on asthma as their experimental endpoint.  Could there be negative side effects of high doses of fish oils that weren't found because they weren't looked-for?  I'm not saying that there are; I'm just making the point that it's hard to prove complete safety of a drug or treatment because there are always a lot of possibilities to test.  You won't find what you don't look for.

In the long run, the real importance of the current findings may be that they encourage further research leading to a much more targeted approach to preventing asthma than just ingesting large doses of fish oils.  It's a start.