L-Glutamine: Helps with muscle soreness and recovery, improves gastrointestinal and immune function, may help with leaky gut and ulcers, supports brain health (addiction, anxiety depression, Alzheimer's, seizure disorders, and more), promotes muscle growth, supports metabolic and heart health, great as a chemotherapy adjunct to support gut lining permeability
Huang X, Huang L, Lu J, Cheng L, Wu D, Li L, et al
Biotin, Collagen & Keratin a beauty multicomplex featuring Biotin, Collagen, Keratin, Hyaluronic Acid, Vitamin B-complex, Vitamins A & E, and natural botanical extracts
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Every cell in your body relies on dietary protein not only for tissue growth, but also to regulate the complex hormonal and metabolic processes, nourish eggs and sperm, build the placenta, and even support breast milk production. 
They're more easily absorbed into the body than oral supplements, which is why they're being prescribed by doctors more frequently