l lost 70 lbs of fat a few years ago, and since then, l have been weightlifting. However, since l have a slow metabolism, l can not eat huge amounts of food that health experts say a weightlifter should eat to get results. what should l do because when l increase food (even healthy), l gain fat?!!

Work out harder man, and eat lots of proteins

Exercise, not just lifting weights. Run, walk, be active. The harder the exercise the more it boosts your metabolism.

People who have slower metabolism do not need as many calories to build muscle. The same metabolism that causes u to gain fat with less calories should also help u build muscle with less calories.

l recommend figuring out ur Total Daily Energy Expenditure (TDEE aka ur maintenance level), & eating only 5% above that. You need need lots of extra calories with ur body type.

What u eat can effect things as well.
Good things to eat are..
Carbs: Oatmeal, brown rice, sweet potatoes, 100% whole wheat, all veggies
Protein: Lean meats, protein shakes, eggs (or just egg whites)
Fat (in moderation): Almonds, flax seed oil, olive oil, peanut butter.

Remember that all of that counts towards ur daily calories.