Patient description: A 42-year-old healthy woman came to the clinic to have her flu shot in early October. She works in a rehab center and has no underlying disease. It's her first time getting the vaccine this year. She is married for 5 years and uses barrier methods of contraception. Her menstrual cycle is irregular. She does not smoke. She is not on any medications. She exercises regularly for 30 minutes a day at least 5 days a week. She has no history of allergies to any food or drugs. Her past surgical history is significant for tonsillectomy and she is otherwise healthy.

Clinical trial eligibility criteria: eligible ages (years): 18.0-28.0,  Hormones Female 2. Between 18 and 28 years of age (inclusive) 3. Reported menarche between the ages of 11 and 14 years 4. Gynecological age of less than or equal to 14 years 5. A history of self-reported regular menstrual cycles when not on contraceptive medication of between 25 and 35 days (inclusive) at prescreen and knowledge of date of onset of menses before the screening visit 6. A BMI of 18.5 to 27 kg (Summation)m(2) and a weight >= 93 lbs. 7. Agrees to use barrier contraception method for the duration of the study 8. Agrees to abstain from alcohol consumption during both 5-day diet/exercise study interventions 9. Agrees to abstain from donating blood during the study and within 30 days of completing the study 10. Is willing and able to fulfill the requirements of the protocol and to provide informed consent 11. Able to speak and read English 12. Lives within 50 miles of the Clinical Research Unit  Currently lactating or pregnant or planning on becoming pregnant for the duration of the study 2. Has ever given birth 3. History in the past 3 months of dieting or weight loss amounting to greater than 2 kg (4.4 lbs) 4. > 4 hours per week of aerobic exercise for the past 3 months 5. Has initiated training for an athletic sport or event in the past 3 months that, in the opinion of the investigator, may interfere with the results of the study 6. Currently using hormone-based contraception, including those administered orally, vaginally, via injection, sub-dermally, or transdermally 7. Current use of medications or supplements that may interfere with the results of the study, including: i.Steroids ii.Hormone-based contraception iii.Sleeping pills iv.Homeopathic substances (e.g. Chinese herbs, protein or other powders, and other-the-counter extracts) v.Stimulants (e.g. Ritalin) vi.Antidepressants or anti-epileptic medications or centrally acting anti-hypertensive medications 8. Current use of recreational drugs (alcohol intake will be monitored and excluded during the two intervention periods) 9. Unable to consume food containing dairy or nuts 10. Has currently or has a history of any of the following: autoimmune, heart, liver, renal disease, diabetes, or another health condition deemed by the PI to be a contraindication to study participation. History of thyroid disorder is permissible if the patient is biochemically euthyroid on replacement. Additional to be Met Prior to Start of Intervention(s): 1 Habitual energy intake between 35-55 kcal/kg LBM*day 2 VO2max less than or equal to 40 ml/kg/min with the option to increase this at the discretion of the PI, depending on the current and past exercise level of the participant 3 Hemoglobin, prolactin and TSH within normal female range for testing laboratory. 4 Ovulation confirmed in the cycle before each study intervention by self-reported positive urine test, ultrasound and/or progesterone blood-levels