In addition to providing slow burning complex carbohydrates, lima beans can increase your energy by helping to replenish your iron stores. A cup of lima beans contains 24.9% of the daily value for this important mineral. Particularly for menstruating women, who are more at risk for iron deficiency, adding to their iron stores with lima beans is a good idea—especially because, unlike red meat, another source of iron, lima beans are low in calories and virtually fat-free. Iron is an integral component of hemoglobin, which transports oxygen from the lungs to all body cells, and is also part of key enzyme systems for energy production and metabolism. And remember: If you're pregnant or lactating, your needs for iron increase. Growing children and adolescents also have increased needs for iron.