Agreed, not a good idea to really diet, but it's always a good idea to eat as healthy as you can for both you and the baby. Not only does dieting limit your calories, and the baby does need a certain amount to develop properly, but it might also keep you from getting the nutrients from certain foods that you need. Alone, we can and do restrict our bodies sometimes from certain types of food while we're dieting, when we're pregnant though we're eating to nourish the baby. Exercise is generally good, just be careful not to overdo and now that it's heating up a bit, not to overheat. Drink lots of water and make sure your blood pressure doesn't get too high. It might be good to invest in a blood pressure monitor, if you're not used to exercising much. Loved prenatal yoga btw.
It isn't safe to diet per se, because you still need to take in x amount of calories per day. Exercise is great for both mother and baby, just make sure you don't overdo it. Walking, yoga, and swimming are excellent for pregnant women. As for your diet, just make sure to cut out junk food (if you ate any previously) and replace it with fruits, veggies, and protein.
You should also speak with your OB/Midwife about weight management during your pregnancy. I was concerned with my weight gain while pregnant because I had severe morning sickness the whole time, and was unable to gain weight. My midwife helped me to manage my diet so that I felt more confident.
Thanks. I will have to tall to him
This is something you would want to talk to your doctor about. It might not be a bad idea, but there may be a way that your doc would prefer. One thing thats safe and can kinda jump start things though is if you drink soda, cut down and replace it with water. It's amazing how many calories/sugar you get from soda and the pounds you can shed from either cutting down or just giving it up (i still enjoy a soda once in a while myself lol).