It can be due to anemia, phase preceding menopause,
diabetes and low or high
thyroid functions
I hope that she's not overweight
If so,make changes in diet with less fats,heavy proteins and carbs
More of seasonal vegetables and fruits and light digestible foods and more water and ORS
Next Steps
get blood tested for cbc,
sugar and
thyroid profile ( both tests are done, fasting for 8-10 hours
Health Tips
get back here with reports for more guidance