In female athletes, lack of menstruation is often a sign of RED-S (relative energy deficiency in sport) - insufficient calorie intake and/or excessive energy expenditure, which can jeopardize long-term physical and psychological health (impairments to menstrual and hormonal health, bone health, immunity, cardiovascular health, metabolic rate, and mood state). 18 year old powerlifter, R, approached us because she was not having a period despite partaking in perceived “healthy” behaviors – training regularly, staying active during the day, and eating lots of whole foods. While these are certainly not detrimental to health, when they result in insufficient calorie intake they no longer have the desired positive effect. We implemented appropriate calorie and macronutrient goals to support health and performance, monitoring and adjusting numbers until weight change in the positive direction occurred. This came with replacing some of R’s whole food intake with more processed carbohydrates and calorie-dense foods to alleviate the extreme fullness she was experiencing at this higher calorie level. Incremental increases in intake led to a little over 1000 calories above her initial consumption before steady weight progress was observed, accompanied by the return of her period 3 months in. This also resulted in marked improvements in energy levels, mood state, and training adaptations – including setting a state record in the deadlift and squat 5 months later.