Hiya Azzira! :)
Gaining weight without re-clogging your system IS a challenge. For me to direct you properly, I need to know what your Dosha is and preferably your blood type too, if you know it. If you don't, tell me your genetic background, like nationality.
Read the posts under yours on this page - lots of info on rebuilding body mass. :)
Are you currently challenged by candida? Or was it just IBS type things?
One thing I can recommend to everyone is the Kichadi recipe, nut butters, and this protein drink, but you HAVE to take pancreatic enzymes with it:
6
oz Vanilla Rice Milk
2 raw eggs - organic free range!
1 tblsp of lecithin
1 tblsp of flax seed oil or Udo's PRime
cinamon to taste
extra vanilla to taste if desired
pancreatic enzymes
Add 10 almonds and blend away. Should be blanched (or with shell) raw, soaked in water overnight.
You should be able to drink this in between your main meals without imbalancing yourself. :)
Sweet potatos are very balanced, a perfect food, and good for maintaining or gaining body mass. Find the yellow ones, not the dark orange yams, altho those are okay too.
Always eat at least one meal a day that is 3 to 1 ratio of basmati rice to beans - mung beans are tasty, as are aduki. Choose the bean by taste or Dosha. Spice it to balance your dosha and digestion both.
Drink more water. For some reason, being really well hydrated can help you gain weight, especially if it's cool but that's risky as it may reduce your power of digestion. If you can find a low-salt organic veggie or chicken broth, drink that too.
If your weight loss is connected to adrenal exhaustion or liver exhaustion and hormonal issues, consider taking an herbal compound of Gotu Kola and Licorice. Solaray has one or maybe Nature's Way.
Every night, drink the tea-less Chai drink with extra honey and almonds added (see Increasign Digestive Power Notes page 13).
Hope that helps! :)