Hi dude,
The main confusion here is over the use of the word 'processed'.

In the same way that wearing clothes is technology, cooking food is processing. Taken literally, cooking food is 'a process', but that's a world of difference from the usual vernacular meaning of "processed food".

The evidence for cooking SOME food is good; for example we get very little nutrition out of raw broccoli, but once it's warmed up sufficient to soften a little and break down some cellulose, we can digest more of its nutrients.

So firstly the statement 'processed food is more efficiently absorbed by the body' is here taking the concept 'cooked' as meaning 'processed' and then metaphorizing incongruously by using the term 'processed food' with no indication of this limitation, apparently in an attempt to mislead but possibly from genuine ignorance (of which there is still a lot in nutritional science).

Secondly, even if it were true that ALL processed food were more easily absorbed by the gut, that says nothing about how healthy it is. Being 'easily absorbed by the gut' can be a very bad thing; for example belladonna is very easily absorbed by the gut, and so is arsenic. Hemlock tea goes down a treat as well  :  ) 

Thirdly, a diet of processed food usually means fast-release carbs, and it's well know that fast-release "easy to digest" foods don't take much energy to digest -but they're gone in a flash and the person is hungry again, eating several snacks and meals in the same time someone on healthy food would still be digesting one meal. Overall, the energy spent digesting food is actually greater, because the processed food eater has to eat more often.

Fourthly, the whole idea of slow-release carbs is that they're SLOW to digest which gives us a constant, regular supply of energy instead of the spikes and troughs created by a processed food diet. We know that 'spiking and troughing' due to 'easy to digest' foods is related to lots of nasty diseases like metablic syndrome & diabetes & obesity.

Fifthly, for the first part of human history we were hunter gatherers. There isn't any evidence I know of that homo sapiens 'hunter gatherer generation' 1 had smaller brains than homo sapiens 'fast food century 21 generation'. If you know of any, let me know, but I was watching a documentary just last night* about human bone development and the researcher pointed out that eating processed food has made the human jawbone smaller over the millennia, and he showed examples of skulls from all periods to explicate this. The brain cases were all pretty similar, but the modern dudes' jaws were indeed smaller.

I don't have time to follow this up right now but if you research each of the points I've made you'll find a bunch of science papers saying the same thing.  ...Who funded this study, one wonders? -Or is someone touting for future funds? In future, stick to sites such as PlosOne where all funding sources and any conflicting interests are stated.

...Wow you just caught me in the mood  :  )  Will that do?
Best,
AR

*Prof.Ben Garrod, 'Secrets of bones; Food for Thought' BBC4