Perimenopause and menopause change a lot at once: hormones, sleep, mood, and how your body carries weight. If you’ve searched for how long this stage lasts, what the symptoms are, or why your weight feels different this year than it did five years ago, you’re not alone. Two things the Prolon 5-Day Fasting Mimicking Diet (FMD) can help with during this stage are menopausal weight gain and muscle protection.