Is it possible for a woman in their 30s

Of course it's possible. I'm 34 and I'm the fittest/thinnest I've EVER been. Even in high school I wasn't this small.

You can do anything if you put your mind to it!

I am 5' tall and 40, and I have lost 79 pounds since January 2012. You can do it.

Yes I think it is. I've seen people I'm their 50s do it. I'm 27 and I'm doing pretty well with it. Stop telling yourself you will fail.. Your sabotaging yourself! X

I am 31yrs old (5'4")and can tell you it IS possible cupcake! I am 18lbs away from the lowest weight I have ever been (100lbs loss) and 48lbs away from what might be my ideal weight.Trust and have faith in yourself because no one else can do that for you doll! xo Best of luck!

Nothing is stopping you so be positive.

You do need to see it as a long term change though, not something to get over and done with.

Weight loss is gradual, it is hard to take this in when you read about celebrities dropping 5lbs a week, this is an impossible figure, they aren't losing 5lbs of fat a week so pay no attention.

Take it slowly, follow the advice, don't cut calories too dramatically - do what is advised, work-out some more but eat what you like all in moderation though then there is no wagon to fall from.

Quick answer: yes

More long-winded advice (take only what you wish): I think the most likely reason that you might not reach your goal is if you stop trying. That is so easy to do. In my past, I've "tried too hard too fast". I know this is a bit counter, but if you all the sudden cut the calories you eat in half and go to the gym every day when you never went before, you may burn out...I always did. Here are my suggestions (again, take only what you find useful):
1. Start logging your calories today. Don't do anything special (eat what you want and don't do any more exercise that you normally do). Log everything. Every little 20 calorie bit of candy. Everything. When I did that I found I was eating ALMOST DOUBLE what I was supposed to eat. Use this to put things into perspective.
2. Set a goal not to eat more than your sustainable calories. In other words...don't try to lose weight, just get yourself to eating the number of calories to neither gain nor lose weight. This doesn't seem like a great goal...after all you want to lose weight. But you need to train yourself to eat/exercise properly at the correct balance...then focus on losing weight.
3. Think of "ultimate dream" and "goals". They are different for me. My ultimate dream is to be in the "normal" BMI range. But, if you judge your success on perfection, that might be discouraging. Instead, set small, stretch goals. These are hard, yet achievable goals. For me, I target to lose and maintain a certain weight. I was 250 and targeted to get to 240. Once I made that and stabilized, I targeted 10 pounds less. Don't over-think this. Even though these goals are artificial, you will feel a sense of accomplishment in achieving them...and you should!
4. Don't expect validation from others. People can act without thinking. They won't always recognize your successes and may even discourage you (even if not out of malice).
5. Take a picture of yourself now, and measure yourself (using both a tape measure and a weight scale). Sometimes I found that I "got smaller" but didn't lose any weight. That's normal and you should be proud of that too! This will be embarrassing. Do it anyway
6. Recognize that it will take time. It doesn't matter how slow it is, if you don't stop, you will be successful.

Best of luck.

I loved reading all the posts on this thread! I'll add my own: I'm 36 and started at 185 lbs. I'm doing a low-carb diet and did the couch to 5k program. I logged everything I put in my mouth. I had cheat days, I logged them too. Six months later I am 143 lbs. and in the healthy weight range. I don't think it matters what age you are as long as you eat at a calorie deficit you will lose weight. Also, there are wonderful people here on mfp to help support you and cheer you on. It really helps when you hit those lows that everyone hits at some point in their weight loss. Add me it you like, I'm on here everyday and my diary is open to my friends.

Ummm, yeah. I am 35 have been battling my weight since I was 10 or 12. I started Sparkpeople in February of 2007 and MFP shortly after at 272 and am now at 193. It is entirely possible!!!

and has been obese in her entire life to get ideal weight?

I'm 31, 5' 2 and 218 lbs. I am 90 lbs over from my ideal weight. last time I weight 55 kg (120 lbs) was when I was 9 year old. If I go with the weight loss rate of 1 lbs per week, I will need 2-2 and half year to lose all my extra pound.

I dont mind waiting 2 years or more, but I do admit I bit am afraid I will fall off wagon. 2 years is a long time. and some people even say it's impossible to be slim if you're already in your 30s.

I am 35 and have had 2 kids. I was overweight as a teenager and until I went to university, lost loads and got down to a US size 6/8, put some on when I was around 26, lost weight when I was 30 and got engaged, put it on in my 1st pregnancy, lost it, then put it on in my 2nd pregnancy. My youngest is now 19 months old and I'm in a US size 8 mainly now, so very nearly as small as I was at age 24. My aim is to be a size 6 (I live in the UK so that's a 10 here) although I'd be happy to be a small size 8. I just mainly need to lose my belly now which is the last part to go.

I'm 5'6",my lowest weight at age 25 was 147lbs, and my highest recent weight last July was 220lbs. I am now at 164lbs, aiming for around 150.