How long will it take for an iron supplement to take effect? (for hemoglobin levels to rise)

Couple of weeks: If your anemia is due to iron deficiency and you start taking iron pills, you would see the beginning of the response in a few days, though it may take a few weeks to notice a substantial rise in hemoglobin. For good health - Have a diet rich in fresh vegetables, fruits, whole grains, low fat milk and milk products, nuts, beans, legumes, lentils and small amounts of lean meats. Avoid saturated fats. Exercise at least 150 minutes/week and increase the intensity of exercise gradually. Do not use tobacco, alcohol, weed or street drugs in any form. Practice safe sex. Get HPV vaccine.