Brief Answer: Detailed Answer: Hello Welcome to Health Care Magic. My name is Dr Muhammad Ahmad & i will look into your problem. I have gone through your query and would try to help you in the best possible way. Note:40 years is not an age to have a last period unless you are taking OCP s or something if it happened without any of these factors then get your hormonal and other issues checked.and thyroid as well. What We suggest for a healthy weight loss: (1)Don t eat LESS ,eat HEALTHY Cut down fat and carbohydrate content in your food,eat salads (with no cream and myonnaese) add apple,red beans,boiled corns,leafy veges and boiled chicken to your salad(avoid high sugar fruits like banana mango)...don t do binge eating if you have 3 heavy meals a day have 5 lighter ones,replace normal milk bread with Bran bread,as much fibre as you can take it s good for you..NO DRINKS Like Coke and stuff..switch to natural juice.Eat chicken ..fish (not fried), you can have three-four boiled eggs with yolks removed they have low calories and super energetic. DON T SKIP BREAKFAST, Skipping breakfast is the worst thing you can do.As your body during night goes to power saver mode and when you don t take breakfast it stays on that mode and doesn t burn fat.Do brisk walk regularly(start with 20 min gradually go to 50 mins dont over work yourself) and take a rest day after every 3 days. Don t stuff your stomach: break your daily three meals into five and still don t stuff your stomach ..leave some room... Drink two glasses of water before you eat it will automatically make fill your stomach so some extent and you will end up eating less. Avoid chocolates ,white sugar or anything in which white sugar can be present, Just stay steady nothing changes in a single month tell yourself that you will give yourself 5 months of controlled eating and exercise and yes your health does deserve 5 months of your life.. (2) Pizza,burgers,coke,sprite or any fuzzy sugary drinks =A big NO (3) Fresh fruit juices =YES Conclusion: Under eating always hurts your body sooner or later, some researches say these people get dementia and weaker brain earlier than others,and under-eating also cause weaker bones and muscles and lazy behaviour lack of awareness and many many other issues. So Don under eat but eat things which you should. Always try to avoid slimming meds. Only slimming med i would recommend: Though we don;t encourage it is Metformin 500 mg twice a day it may cause you diarrhea or lethargy in start but soon ur body will adjust to it and it will reduce you appetite time to take it is 2 hours after breakfast and 2 hours before dinner, Wish you health