This is the reason why low fat and sugar free works when it comes to weight loss. Provided you do some moderate exercise as well.

I calculated how many grams per month you would save by first reducing added sugar and second, choosing low or fat free dairy.

Sugar 

One glass of fizzy drink(250 ml) has about 25-30g sugar. 

25-30g everyday (30 days a month) = 750g – 900g.

If you drink one glass of sugary drink everyday, you would have gained almost 1kg!! The opposite applies for when you don’t drink a sugary beverage everyday, you will avoid adding that extra grams every month.

Fats and dairy 

I did the math with full cream milk as well. 

100ml full cream milk has (estimated)  3.4g of fat.

Let’s say for argument’s sake you use 250ml per day ( for porridge and 2 cups coffee/tea daily).

250ml = 8.8g per day

= 260g per month ( 30 days).

As much as you are hesitant to change your habits for weight loss, I think the numbers speaks for themselves.

For fun sake,here is a chart showing how much sugar is in what you drink