Erin is a 28-year-old professional woman who is 5 feet 8 inches tall and vigilantly maintains her weight at 118 pounds by following a lacto-ovo (non-fat milk and egg whites only) vegetarian diet that supplies approximately 1200 calories a day. With her understanding that protein should provide between 10 and 35 percent of her daily calories, she reasons that her daily intake of 40 grams of protein from milk, eggs, legumes, and nuts is adequate for her needs. She is concerned, however, that she has been sick more than usual and has experienced two stress fractures in her leg over the past three years while exercising. How many kcals per day should she take in for optimal energy intake?