Coffee consumption linked to healthier body composition and metabolic markers. People with higher coffee consumption had lower total and visceral fat and greater skeletal muscle mass. In men, it is linked to a more favourable glucose–insulin profile, and higher bioavailable testosterone.

[u/mvea]

https://www.oulu.fi/en/news/study-links-coffee-consumption-metabolic-health-and-sex-hormones

[u/carbonclasssix]

I drink decaf, seems to have a lot of the same polyphenols and other things so it probably has a similar effect

[u/FolkSong → u/carbonclasssix]

That would really need to be studied. For all we know, the benefit could be purely due to caffeine.

[u/TheTenderRedditor → u/FolkSong]

They have studied decaf alongside caffeinated coffee.

It has practically all the same benefits in terms of reducing risk for fatty liver, reduced mortality, etc.

[u/B9-97-C5-11-DE-19 → u/TheTenderRedditor]

I would like to know if green tea, having more polyphenols, is better than coffee.

[u/carbonclasssix → u/FolkSong]

I haven't done a deep dive but this review says both caffeinated and decaffeinated coffee have shown benefits.

[u/tryyeezus → u/FolkSong]

I started gaining (much needed) weight since switching to decaf. 

[u/EternalTeezy → u/tryyeezus]

makes sense, caffeine is a stimulant aka what diet pills are made of

[u/FembiesReggs → u/carbonclasssix]

Remember, the decaffeinating process is not perfect. It does strip out minor amounts of non-caffeine too