I second @web265 on that "At the time of the treatment you'll likely be asked to be "gas (and fecal matter) free and full of pee" as much as possible." The thing is the "full of pee will push your guts further away from the beam, thus protecting them from damage. Foods that produce faeces and gas (mainly beans and veggies) will bloat your intestine to the point that the beam will affect it, thus it is a no- no. Is it difficult (boring) to maintain a diet during RT sessions but you have to do it and then eat that staff you want on Friday night and Saturday morning so there is enough time to evacuate them properly during the week end and before the next session. In my husband's case (gleason 4+4, RP, PSA after RP 3.75, RT 68 Gy in 34 fractions which started 2 weeks after starting ADT with eligard and Zytiga) they only "kicked him out" once (until he evacuated) and it was precisely because he had beans on a Sunday night. But for some reason, the RT equipment used (In Sylvester Comprehensive Cancer Center in Miami) would not start treating you if everything did not look perfect (thank you AI) and when you did have the treatment, you would not have side effects. Nothing burnt, no diarrhea, no muscle loss - nothing - all perfect.

Now eggs? he is eating 3 eggs daily on breakfast. (organic, pasture raised). His medical oncologist and radiologist oncologist said nothing about eggs, but yes, red meat. Stay away from red meat. Stick to vegetable sources of protein the said. If it has to be read meat, have very little (like 250 gms per week) and be sure it is hormone free. Dairy ... likewise. We all know dairy is made of milk - milk is made of animals that are either filled with hormones or caged, raped and frustrated whilst we milk them - do you really want to get all this into your system? I am greek and still don't eat greek yogurt - or any yogurt. (you can get your probiotics from a trillion other natural sources).

And yes - we did talk to a nutritionist from the same hospital - she was actually an italian and we ended up giving each other our grannies recipes. Because at the end of the day the mediterannean diet is what everybody suggest we all have, cancer or not. Back then we did not eat red meat at all. Maybe twice a month? it was only fish and chicken and that would be twice or three meals a week. The rest was based on beans, salads, veggies, home made bread (with sour dough), olive oil etc etc.

A tip: Husband is pre diabetic (only very very sightly, yet we have to get him to normal levels. Nutritionist suggested berberine, 1000 mg per day with food (as opposed to metformin). Cancer loves sugar (needless to say 0 sugar and 0 refined foods in your diet - I would also add 0 sweeteners as them too, apart from being non-natural, will tell the brain to tell the pancreas to produce insuline for no "real" reason). Have fruits (not dried fruits).

End of story - husband lost the extra weight, 8 months after RP and RT and 6 months into ADT he is in very good shape (30 min walking daily and he doubled his muscle exercise regime to counter the effect of ADT), eats as natural as I can manage and his blood results better than ever before.

Also prescribed by oncologist together with 1000 zytiga, is 1000IU vit D, 1000 calcium, 5mg prednisone. Calcium and vit D are important to help with your bone loss. Exercise is equally as important. Good luck. You are going to beat this.