I look at number of subjects, double blind, self reported, etc.

I am a sciency guy who spent many years in medical research. Most of us are in a sense "sceptics at heart". One needs to be flexible and willing to replace ideas that are disproven and much more. I look at the sources and always try to read the original research papers when possible and not rely on opinion pieces about the original papers. I like articles from Mayo clinic myself and from NIH too. Even with some of the best studies like the National Weight Control Registry which follows over 10,000 participants long term you have to look at the specifics. Sadly all of the results there (by necessity) are self-reported and even worse "self-defined" in regards to some critical factors. Eating breakfast is highly touted and about 78% of the successful participants self-report that they eat what they believe to be breakfast (self-defined). When groups of folks are questioned the percentage of participants eating within 1 hour of arising for example drops off from that percentage. Without definition the meaning of "breakfast" loses it value as we all in a sense "break the fast" and eat sometime. Sounds picky but that is what double-blind, peer reviewed science is.
Another splash article about eating late and obesity in Spain is shown to be about something quite different. The authors who were being paid by a grant could in no manner show ANY correlation between eating late at night and obesity so they showed by statistics that folks who ate a later lunch had some correlation with obesity. They went on to rationalize that their title wasn't erroneous because many folks in Spain eat large meals for lunch. I was unimpressed.

I don't follow any of the studies. I believe what Fat @FatCrankyGoat said "eat as healthy as possible; avoid processed foods as much as possible; and offset it all by living an active lifestyle!"
The only problem is actually doing it.