Except the books by Gary Taubes, Nina Teicholz, Jason Fung, Tim Noakes… etc. are very well researched and sourced. Go look at the bibliography and footnotes. Go run down the sources yourself if you are worried. I have checked out and corroborated a lot of it because I care to do it and I have an academic background.
The argument that because someone can always say the opposite and therefore we can’t know what is true is not only sophistical, but a logical fallacy. The science, as far as I’m concerned, is becoming quite clear about how the metabolism, diabetes, and obesity works, esp. if you read those authors. Tim Noakes was tried for crimes in South Africa for speaking the truth and vindicated after the court considered thousands of pages of evidence for LCHF diet and heard from witnesses from all over the world who supported him.
Noakes used to be a low fat / exercise advocate, but totally changed his mind on the premises of the science.
If you haven’t done the research yet, then you should be worried. Go inform yourselves and stop worrying… at the very least read Taubes’ “Good Calorie, Bad Calorie.” It’s dense but you can do it in a couple of days of reading.