The article linked to the claim is from Nature.com, a peer-reviewed research journal that requires a paid subscription. I do not have access to this site, but I have already found distrust in the article. First, the title of the article is “Eating less can lead to a longer life: massive study in mice shows why”. This stood out to me because I personally believe that studies using mice and other animals can only prove so much about human bodies as they are a totally different species. Disregarding my own opinion, this article is still not readily accessible.
After googling “Does eating less lead to a longer life?”, I found an article from Science.org, a scientific journal published by American Association for the Advancement of Science (AAAS). In summary, the article discusses findings of a gene in yeast called SIR2, that is related to its lifespan. According to Leonard Guarente, a molecular biologist from the Massachusetts Institute of Technology, “cutting yeast cells' glucose intake by as much as 75% increases their lifespan by 25%.” The article then states that although humans don’t have the same genes as yeast, they do have a similar gene that is believed to relate to aging: “If that gene proves important in aging, Guarente says, it may provide "one of the most promising avenues toward getting a drug that would affect the aging process." Although these scientists have made discoveries in how certain genes work, they have not yet proven that reducing your caloric intake will lead to a longer life.
I also looked at an article from the National Library of Medicine called “Beneficial effects of intermittent fasting and caloric restriction on the cardiovascular and cerebrovascular systems”, written by Matt P. Mattson. This articles states that intermittent fasting (reduced meal frequency) and caloric restriction extend the lifespans of rodents and monkeys but does not include information regarding the effects on humans. It describes how these techniques strengthen the cardiovascular and brain functions in these animals as well as helping to prevent diseases and other factors that could decrease life span.
Although this information seems to be accurate and supported by credible sources, these studies have been done on rodents and other animals, not humans. There is little information proving that eating less actually increases life spans, but more information showing that following healthy eating practices and techniques will prevent diseases and health problems, that would therefore indirectly lead to a longer life.
This claim is also tricky due to its wording, as “eating less” is subjective to individuals and is not specific enough to provide a proper claim.
https://www.science.org/content/article/why-eating-less-means-living-longer
https://pubmed.ncbi.nlm.nih.gov/15741046/