Behavioural despair tests get rethink + "Nutrition science is broken"

#1
C C Offline
Depression researchers rethink popular mouse swim tests
https://www.nature.com/articles/d41586-019-02133-2

EXCERPT: Nearly every scientist who has used mice or rats to study depression is familiar with the forced-swim test. The animal is dropped into a tank of water while researchers watch to see how long it tries to stay afloat. In theory, a depressed rodent will give up more quickly than a happy one — an assumption that has guided decades of research on antidepressants and genetic modifications intended to induce depression in lab mice.

But mental-health researchers have become increasingly sceptical in recent years about whether the forced-swim test is a good model for depression in people. It is not clear whether mice stop swimming because they are despondent or because they have learnt that a lab technician will scoop them out of the tank when they stop moving. Factors such as water temperature also seem to affect the results.

“We don’t know what depression looks like in a mouse,” says Eric Nestler, a neuroscientist at the Icahn School of Medicine at Mount Sinai in New York City.

[...] “The National Institute of Mental Health has for some time been discouraging the use of certain behavioral assays, including the forced swim and tail suspension test, as models of depression,” [NIMH director Joshua] Gordon said in a statement to Nature. “While no single animal test can capture the full complexity of a human disorder, these tests in particular are recognized by many scientists as lacking sufficient mechanistic specificity to be of general use in clarifying the neurobiological mechanisms underlying human depression.” But Gordon said that the tests are still “crucial” for some specific scientific questions, and that the NIMH will continue to fund such studies.

Although scientists insist that behavioural tests that cause stress in animals are necessary for developing human treatments, the PETA campaign [against forced-swim testing] dovetails with scientists’ growing concern about the quality of data produced by forced-swim tests, says Hanno Würbel, a behavioural biologist at the University of Bern. “The point is that scientists shouldn’t use these tests anymore,” he says. “In my opinion it’s just bad science.” (MORE - details)



Nutrition Science Is Broken. This New Egg Study Shows Why.
https://undark.org/2019/07/18/science-of-eggs/

INTRO: It’s been a tortuous path for the humble egg. For much of our history, it was a staple of the American breakfast — as in, bacon and eggs. Then, starting in the late 1970s and early 1980s, it began to be disparaged as a dangerous source of artery-clogging cholesterol, a probable culprit behind Americans’ exceptionally high rates of heart attack and stroke. Then, in the past few years, the chicken egg was redeemed and once again touted as an excellent source of protein, unique antioxidants like lutein and zeaxanthin, and many vitamins and minerals, including riboflavin and selenium, all in a fairly low-calorie package.

This March, a study published in JAMA put the egg back on the hot seat. It found that the amount of cholesterol in a bit less than two large eggs a day was associated with an increase in a person’s risk of cardiovascular disease and death by 17 percent and 18 percent, respectively. The risks grow with every additional half egg. It was a really large study, too — with nearly 30,000 participants — which suggests it should be fairly reliable.

So which is it? Is the egg good or bad? And, while we are on the subject, when so much of what we are told about diet, health, and weight loss is inconsistent and contradictory, can we believe any of it?

Quite frankly, probably not. Nutrition research tends to be unreliable because nearly all of it is based on observational studies, which are imprecise, have no controls, and don’t follow an experimental method. As nutrition-research critics Edward Archer and Carl Lavie have put it, “’Nutrition’ is now a degenerating research paradigm in which scientifically illiterate methods, meaningless data, and consensus-driven censorship dominate the empirical landscape.”

Other nutrition research critics, such as John Ioannidis of Stanford University, have been similarly scathing in their commentary. They point out that observational nutrition studies are essentially just surveys: Researchers ask a group of study participants — a cohort — what they eat and how often, then they track the cohort over time to see what, if any, health conditions the study participants develop.

The trouble with the approach is that no one really remembers what they ate. You might remember today’s breakfast in some detail. But, breakfast three days ago, in precise amounts? Even the unadventurous creature of habit would probably get it wrong. That tends to make these surveys inaccurate, especially when researchers try to drill down to specific foods.

Then, that initial inaccuracy is compounded when scientists use those guesses about eating habits to calculate the precise amounts of specific proteins and nutrients that a person consumed. The errors add up, and they can lead to seriously dubious conclusions. A good example is... (MORE)
Reply


Possibly Related Threads…
Thread Author Replies Views Last Post
  Controversial psychology tests are often still used in US courts C C 0 98 Feb 19, 2020 04:15 AM
Last Post: C C
  Daryl Bem proved ESP is real. Which means science is broken C C 1 436 Jun 14, 2017 05:13 PM
Last Post: Magical Realist
  The Broken Technology of Ghost Hunting C C 17 2,719 Nov 24, 2016 06:26 PM
Last Post: Zinjanthropos
  Science Isn’t Broken C C 2 933 Aug 28, 2015 07:44 PM
Last Post: Yazata



Users browsing this thread: 1 Guest(s)