I'm not a dietition but trainers in gyms will give you hit and miss advice some are set on selling certain types of products others have no real clinical experiences with food and nutriition and others are incredibly good! My advice if your pocket book allows it consult with a good registered dietition and tell them of the gender change in body (if you feel you can entrust them) they may give you midifed advice or a specialized diet a trainer in a gym would not know of or think about doing?
I know food carbs do not hurt me drink carbs (sugars do) like carbonated sweetened beverages, nasty stuff i love pepsi but try and limit a bottle or can a day in evening! they're sugars i do not wanna confuse: complex and simple carbohydrates Your body breaks these down for various things for energy, eat too much do too little you end up storing too much.
Proteins are a little slower acting takes body longer to break down and get uses out of Carbs break down a little faster. Hikers for example eat a lot of calories but 50-60% are recommeneded to be carbohydrates cause they break down a little quicker and give you fuel as you go, proteins tke longer and kick in later on when you need them after hiking or resting for recharging and repleneshing.
Do not ignore the basic things, vitamin D, plenty of vegetables, and fruits! Greener the vegetable the better it is for you!
Things like iceberg lettuce although crunchy no ZERO nutritional benefit! Spinach leaves, broccoli, romaine lettuce, green beans, have more minerals and vitamins! So remember GREEN IS GO! Most fresh fruits and vegetables are fat free they have some calories and such. If trying to bulk incorporate your fats wisely, like do not eat a juicy steak with a 3" thick ribbon of fat thinking that will help you! That goes into your arteries, nasty stuff! although i love steaks! T-bones and porterhouse steaks are my fave! Anyway incorporate fats like whole butters, good oils into your cooking and foods. Eat plenty of regular yogurt and cottage cheeses if you like them! Darker fishes are the fattier ones more calories to.
Sorry rambling too much here!
Just my .02