There is no research to support rotating certain foods into and out of the diet based on the menstrual cycle phase with the goal of “supporting” hormonal health. Menstrual cycle-based diets usually recommend some variation of the following: eating anti-inflammatory and iron-rich foods, (like salmon, red meat, and dark leafy green vegetables) during menstruation, eating “proestrogenic” foods (like flax seeds and kimchi) during the follicular phase, and eating foods that “balance” blood sugar and support progesterone (like complex carbohydrates, avocados, tofu, dark chocolate, and pumpkin seeds) during the luteal phase. These recommendations (e.g.,like eating iron-rich foods when losing blood through menstruation) certainly aren’t unhealthful or completely unfounded, but they are not an evidence-based way to “balance hormones”.