Effects of Beef Consumption on Skeletal Muscle Protein Homeostasis and Inflammatory Factors in Pre- and Postmenopausal Females

Effects of Beef Consumption on Skeletal Muscle Protein Homeostasis and Inflammatory Factors in Pre- and Postmenopausal Females

This will be a randomized study to determine if animal-based protein-rich food sources can stimulate greater muscle protein turnover and whole-body protein balance and reduce skeletal muscle inflammatory markers in postmenopausal women compared to vegetarian base protein-rich foods.

A randomized cross-sectional controlled trial will be conducted to quantify whole-body and muscle protein turnover and skeletal muscle inflammation following 5-days of consumption of either beef or isonitrogenous plant-based sources of protein in normal/overweight and obese post-menopausal females. A premenopausal normal/overweight group consuming beef containing study meals will also be recruited to serve as a healthy control comparison.

Inclusion Criteria:

1. Postmenopausal women ages 50-65 (absence of menstruation for at least 12 months).
2. Premenopausal women ages 35-45 (presence of normal monthly menstruation for the past 12 months).
3. BMI of 20.0 - 34.9 kg/m2.
4. COVID-19 negative and/or asymptomatic

Exclusion Criteria:

1. Any substantial musculoskeletal injuries/diseases that have limited daily activities in the past month.
2. Unable to stop the use of anti-inflammatory drugs for the week prior to and during study.
3. Diagnosed metabolic or hormonal disease (i.e., renal, cardiovascular, thyroid, polycystic ovary syndrome, or type I/II diabetes mellitus).
4. Currently pregnant.
5. Gave birth or was lactating within previous 12 months.
6. Undergone gastric bypass/bariatric surgery.
7. Clinically significant weight gain or loss (>5% change) in the last 12 months.
8. Consuming metabolism-altering drugs or medications (i.e., corticosteroids, stimulants, insulin, thyroid medication).
9. Unable or unwilling to suspend anti-clotting medications including aspirin use for 5 days prior to Visit 4.
10. Participating in >200 minutes/week of vigorous exercise and/or >4 days/week of resistance training.
11. Unwilling to fast overnight.
12. Surgical menopause.
13. Having undergone hormone replacement therapy in the last 12 months.