There is an account on Twitter called “Speaks only in mice‘, which is very similar to what the title says. Whenever a study on lab mice appears in the media and the results are described as if they could be applied to humans, the Twitter account adds important context by quoting the study and simply saying “…IN MICE” .
We may now need to create a second account, “Just Says in Zebrafish”, in order to respond to a new study that appears to show that “Intermittent fasting can cause fertility problems“. And, perhaps, this shows that – “… IN RENIORENIO.”
If you’re used to reading the scientific reports on the health benefits of intermittent fasting, which is all the rage right now, you’ll be surprised by this new study that highlights a major potential downside – the risk to your fertility. But once you understand that no one is involved in the investigation (and, frankly, this has been mentioned in a lot of media somewhere, even if it wasn’t in the headlines), you can start worrying less about it to be on the safe side.
Leaving the human transmission for a moment, let’s look at what has been done to these zebrafish. The experiment was fairly simple, although the picture of the results is quite complex. The first thing to note, as mentioned elsewhere, is that Lent did not last a day or several evening hours. The starving fish went without food for a full 15 days before the effects of starvation were measured.
Zebrafish that were starving or eating normally this way had part of their fins cut off (oops!) to see if fasting would help them grow them back faster. Later, they were mated with other fish of the opposite sex and given some time – a maximum of five hours – for the “spawning” of offspring. The eggs were collected and the scientists recorded the total number of offspring and the survival time of the offspring.
When they looked at the results for the entire sample, they didn’t find much. Only after the authors divided the fish into a group of males and a group of females did they begin to see results.
For example, there was some evidence that fasting females grew fins faster than normally feeding females, suggesting some health benefits of fasting. But since the difference between fasting diets was not statistically significantly greater in women than in men, it’s hard to say what to do with this result.
They also specifically looked at sex in terms of their reproductive success. At first, the results seemed paradoxical: during fasting, females produced fewer offspring – a sign of reduced fertility – but these offspring lasted longer, indicating that they were of better quality. They did not find this trade-off between “quantity and quality” in males, which showed a decrease in offspring after starvation. AND in the likelihood that the eggs they fertilize will survive.
After the sober females began to feed again, the scientists saw the opposite result: the fish began to produce more offspring, but of lower quality.
There are some statistical issues here. First, unlike the results for fin length, I could not find any analysis in the study that directly compared the difference between fasting and feeding males and females. If you say fasting affected one gender and not the other, you really should check to see if the effects were statistically different.
And this leads to the second point: it was not clear expected the results in women are stronger than in men, whether it was a surprise. If they predicted this, their theory seems even stronger. If they expected both sexes to have the same impact of fasting on their fertility, then these results could be proof. in turn for at least part of the theory.
And this theoretical element is really important here: from the point of view of evolution, the results are the most interesting. The question that animals might be programmed by natural selection to act when food runs out for an extended period of time—what happens when they find food again—is intriguing. The idea that during times of famine they start investing in fewer, higher quality offspring makes a lot of evolutionary sense.
But, as the authors themselves acknowledge in their article, the fact that it is interesting from an evolutionary point of view does not make it directly relevant to the practical, human question of the effects of fasting. Of course, zebrafish are a “model organism” that allows us to test hypotheses in a highly controlled environment, but they are also far from humans in terms of their metabolism and the conditions under which they will starve. . The only way Real To find out if fasting has similar effects on fertility in humans, it would be… to do a human study.
However, the press release accompanying the study is worded in terms of fasting and discusses a “popular health and fitness trend” that “people do to lose weight and improve their health.” It’s not that they hide that the results were in the fish – it’s very clear. But they seem to want both, indicating that they have nothing to do with people, but still talk a lot about people.
I think it’s a shame: the results of the study are interesting enough without making them practical and relevant to people. Sometimes a biology degree can stand on its own without getting people into the equation, even if it’s just “…In ZEBRAVIS.”
Source: I News
With a background in journalism and a passion for technology, I am an experienced writer and editor. As an author at 24 News Reporter, I specialize in writing about the latest news and developments within the tech industry. My work has been featured on various publications including Wired Magazine and Engadget.