At the moment our three-month-old baby wakes up for a feed twice every night. He goes to bed at around 7 pm, wakes up around midnight for the first feed, then again at around 4 am.

I read in a magazine that a study involving 600 babies showed that if you want the baby to learn to sleep through, you must gradually step down the amount of milk given the baby at night time.
(Source: the British magazine "Archives of Disease in Childhood". The article is based on a study from London University).
It says that when a healthy child is three weeks old, the parents should gradually delay the breast- or bottle-feeding when the child wakes up at night. And you should change the nappy before you give the baby milk, so the child stops connecting the wake-up with the pleasure of food. The child then should just fall asleep again.
Also, according to the article, at bedtime, the sleepy baby should be put to bed quickly without any food or cuddling.
Now, I am questioning this. I worry that my child is not growing as much as he should, and there is no way I'd want to see him to go through the night hungry.
On the other hand, of course, I WOULD like to somehow reach that point where he sleeps through.
Anyone with good advice on this issue?