Kitten diet - how much to reduce his food by?

Hi everyone. 

Hope you don't mind me asking you all for some advice. 

My kitten (11/12 months) went to the vet today and while I was there she told me that Higgs is overweight. I was a bit surprised, as he's only 5kg (11lbs) but apparently for his small frame, he should be around 4kg (albs).

He was switched - about 8 weeks ago - onto adult cat food, and I suspect this is part of where the weight gain comes from. He is an indoor cat. 

The thing I am a bit unsure of is how much to reduce his food by. At the moment he gets 1 wet pouch (100g) in the morning and 45g in the evening of dry Purina One.

The vet recommended cutting this down to 0.5 pouch in the morning, and 30g in the evening. I've checked the suggested servings on the packs, and it's 3 pouches for a small adult cat per day, or 65-80g Purina One, so reducing it by this much - a 30%ish - reduction seems a bit drastic. 

Does anyone have any thoughts or advice on how much to reduce by?

i would say do as your vet told you to do, but i read it says make sure your cat doesn't lose more than 1/2 pound per month because that will cause other issues. 

i also read that if you must cut down, cut down on the dry food more than the wet food, like 1 pouch of wet food, and lesser grams of dry. 

but if i were in your shoes i would do as the vet recommended. 

30% is way too drastic. You have to cut back little by little or kitties can get fatty liver disease. I forget what the recommended percentage is, but it's nowhere near 30%, I believe it's around 5%-10% per month.

You should eliminate his dry food. Dry food has more carbs, so it will be easier to lose weight on wet food. Try to get a pate, the pate style is lower in carbs than gravy based foods. Do not get diet (weight management/indoor) food! These are just lower calorie foods. But the lower calories are achieved by more carbs.

@Raintyger  Thanks for the advice Glad that you agree that it seemed a bit drastic. The vet was very vague!

We've decided to do as you suggest, and cut down on the dry food initially - I want him to get a good amount of wet food so we'll look at increasing that and decreasing the dry.

I've not seen many pate style foods - I don't think we get a huge number of them in the UK apart from "treat" ones, but I'll keep an eye out.