You can eat low carb without eating huge amounts of fat. Just stick to healthier fats such as avocados, nuts and seeds(go easy on them), dairy...as long as it doesn't cause you to gain. These fats will help you to feel full. Dont eat low fat...any "benefit " is cancelled out by added salt or sugar. Eat protein such as chicken, oily fish, eggs, some red meat. Add lots of leafy, green veg. Avoid starchy things like pasta, rice, bread. Avoid veggie subs...make a packed lunch of veg, eggs or cheese, lean meat or tinned fish. Or make mini fritattas or eggy muffins* to carry with you. Most fruit is high in sugar...except berries. Try raspberries or blueberries with full fat Greek yogurt.
Eat before gym sessions...but have protein, not just veggies.
And if bacon is "calling" you, have it with eggs and skip the bread.
Hard I know, but it can work if you give it a chance. Good luck whatever you do.
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