Cat or dog person?

Leah Michelle Baines and Jessica Lee Oliva at James Cook University in Australia say they have discovered that people who own dogs tend to be more resilient than those who own cats. They also report discovering that people who own cats tend to be more neurotic than those who own dogs.

Writing in Anthrozoös, they say: “In contrast to our expectations, no other personality differences were found between pet owners…Findings suggest that personality factors might explain why people who choose to own dogs fare better than people who choose not to own dogs during challenging times of social isolation, which may be unrelated to the animal itself.”

Sizing up satisfaction

Much of science depends on the question “how can I measure this thing (whatever this thing is) accurately, precisely and reliably enough to gain insight about it”. That question almost screams – maybe in ecstasy, maybe in agony, maybe in puzzlement – from a research paper that reader Nicolas Clairis brought to Feedback’s attention.

“Do sex toys make me satisfied? The use of sex toys in Denmark, Norway, Sweden, Finland, France, and the UK” was published by Gert Martin Hald, Silvia Pavan and Camilla S. Øverup in The Journal of Sex Research.

How, Feedback has stayed up nights wondering, could one measure that kind of satisfaction in someone other than oneself? Measure it in a way that would make one feel confident that the answer is accurate and true?

Apparently unafraid of the problem, Hald, Pavan and Øverup went at it. They went at it more than a thousandfold. More than 10 times a thousandfold. They sought measurements of a sort from “11,944 respondents from six European countries”.

Feedback hesitates to go into detail here about how the team got and interpreted the 11,944 answers. If the temptation is too much for you to resist, go read the paper. Tell us whether you find its climactic conclusion to be satisfying.

Coffee controversy

Nothing gets kidneys pumping quite the way coffee does — and nothing gets the hearts and minds of kidney researchers pumping quite the way the kidneys/coffee question does. Kidney International Reports sometimes treats its readers to boluses of opinion and fact about this, from researchers who seem emotionally primed and pumped.

A two-part question drives this action: exactly how, and exactly how much, does coffee get kidneys pumping? A back-and-forth between two groups of US researchers began with the publication of “Coffee consumption may mitigate the risk for acute kidney injury“. Its authors say that “higher coffee intake was associated with a lower risk” of kidney problems.

The team looked at data collected during a three-year span, in which 15,792 middle-aged people indicated how many cups of coffee they thought they had swallowed during the previous year – thus, 15,792 self-educated guesses. The study compares those guessed coffee-cup tallies with each person’s record, in later life, of what it calls “acute kidney injury events”, or AKIs.

A second group responded by pumping out a letter called “The missing link between coffee consumption and AKI-water“. The drinks, or the failure to drink, can have overwhelming effects on the kidneys, the researchers suggest. They also suggest that the first group may not have fully considered that.

The first group disagreed, and pumped back a well-maybe-but-Killer response, citing a study about coffee and dehydration. That British study’s lead author: Sophie Killer.

Onward forth, and onward back, sloshes the discussion. More recently, a third group based in China, South Korea and the Czech Republic brought the flow of opinion again into its traditional middle-ground muddle. “In summary,” says the team’s report, “several contradictory effects of caffeine intake on kidney function have been reported”.

Coffee to prevent covid-19

Coffee-drinking can have almost any desired medical effect on a person, to some degree. In some cases, that degree is zero. In other cases, it’s not.

Chen-Shiou Wu at China Medical University in Taiwan and colleagues ran experiments that led them to publish a study called “Coffee as a dietary strategy to prevent SARS-CoV-2 infection“.

Their first experiment asked if coffee could impede the SARS-CoV-2 virus from infecting human embryonic kidney cells nurtured in a lab. Then they drew and did experiments on blood from 64 coffee drinkers. The cell work and the drinker work, combined, led to some optimistic suggestions.

The team reports that the ideal timeline for coffee to inhibit SARS-CoV-2 infection is within 6 hours. “Taken together,” they say, “drinking 1–2 cups of coffee [or even] decaffeinated coffee daily can potently reduce SARS-CoV-2 infection including wild-type, Alpha, Delta, and Omicron variants.” These likelihoods “can serve as a guideline for dietary health during coexistence with SARS-CoV-2”.

At most, this could be the effective, simple treatment that everyone has been seeking. At least, coffee is as efficacious against covid-19 as it is against most other diseases.

Marc Abrahams created the Ig Nobel Prize ceremony and co-founded the magazine Annals of Improbable Research. Earlier, he worked on unusual ways to use computers. His website is improbable.com

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