I prefer a wetsuit that is too large---as this effectively makes it much more flexy feel,they tend to last longer too,downside will not be quite so warm.

ikw777 said...

Have to buy a wetty this week, a 3/2. Trouble is I know that over autumn I will lose about 5kg. (I'm presently 80).

Would losing 5kg affect the fit and therefore effectiveness of a wetsuit much?

Drink more beer in Autumn.

I had trouble deciding on a size when I bought mine last winter. I usually put on 1 -2kgs over winter but I was thinner than usual when I ordered.I decided to go for a size to allow for the extra weight - although I haven't put on any since . I didn't get to really try it out in coldest conditions as it was late spring by the time it arrived .
Maybe it won't be quite as warm as it could be but I figured I could always wear my 1mm metallic over shirt if I was cold and at least I wouldn't have a wetsuit that I couldn't get into.
I had to buy via the internet as I wanted a 4/5 3mm one and couldn't get any locally.

No matter how much weight you lose your bones will be the same. Same arm/leg length etc. Same distance from shoulders to crotch. So, unless you've got a mega gut and lose that, your wettie size will stay the same.