"Many DJS patients just have a sloppy diet after the surgery, what is the main cause of many problems, which occur during and after the recovery phase (in my oppinion)." - Interesting. What 'many negative affects' can poor diet have in your opinion? How can they avoid this..? Just eat nutritious food basically?
The main negative effect is just the same like in every surgery: You stop being active for a certain time period. Stop being active accerelates your aging process, that means your body degenerates. The degeneration process is really fast. If Athletes stop doing training for a month, then they are losing 20% of their strength (after 1 month!). And that was just the strength lose. The reduction of your endurance is even faster. Especially losing endurance is really painful, that is what makes you feel really old.
After a DJS this degeneration process is even faster for many patients, because they don't eat well. So yes, what you can basically do is to eat proper. That is possible, if you just drink liquid food and it should be real meal replacement liquid food, not just soups or some smoothis.
For soft tissue healing you need alot of amino acid, so a higher protein intake after a surgery is necessary.
Anyway, I think it was enough offtopic.