A healthy vegetarian diet falls within the guidelines offered by the USDA. However, meat, fish and poultry are major sources of iron, zinc and B vitamins, so pay special attention to these nutrients. Vegans (those who eat only plant-based food) may want to consider vitamin and mineral supplements; make sure you consume sufficient quantities of protein, vitamin B12, vitamin D and calcium. You can obtain what you need from non-animal sources. For instance:
Calcium: For adult women aged 19-50, the USDA recommended daily allowance is 1,000 mg/day. For women over 50, the recommended daily allowance is 1,200 mg/day. Good sources of calcium include dairy products, leafy green vegetables, certain fish, grains, tofu, cabbage, and summer squash. Your body cannot take in more than 500 mg at any one time and there’s no benefit to exceeding the recommended daily amount.
Fluids: Fluid needs increase as women age. The reason: Kidneys become less efficient at removing toxins. “Drinking more fluids helps kidneys do their job,” Schwartz says. “Unfortunately, thirst signals often become impaired with age, so people are less likely to drink enough water and other fluids.” Rather than fret about how many glasses to drink, Frechman says, check the color of your urine. "It should be clear or very pale colored. If it becomes darker, you need more fluid.”