The only way you can permanently and physically reduce the size of your stomach is to have surgery. You can lose overall body fat over time if you eat healthy foods, but that won't change the size of your stomach.
Many women also notice an increase in abdominal fat as they age, even if they do not gain weight. This is likely due to a decrease in the level of estrogen, which appears to influence where fat is distributed in the body.
Squats down. Yes, this leg day staple is a great way to work your entire body, strengthening your leg and building a solid midsection.