Navigator for the protein-nutrition and supplement clusters — how much protein and which sources change an outcome, how quality is scored, and which supplements earn their place. The muscle, strength, bone, and function side (sarcopenia, grip, resistance training, fracture) moved to Musculoskeletal Health and Physical Function Hub; protein’s role in building muscle is cross-referenced there. Nucleus of the quality side: Protein Quality and the DIAAS Score.
Protein — how much, which source, and mortality
- Protein Intake for Older Adults — how much protein an older adult needs, daily (1.0-1.2 g/kg/d, 1.2-1.5 in illness) and per meal (~25-30 g / 2.5-2.8 g leucine), why the RDA undershoots, and the severe-CKD contraindication (its muscle-preservation mechanism: Anabolic Resistance, in the Musculoskeletal Health and Physical Function Hub)
- Dietary Protein and Mortality — the mortality half (Naghshi 2020, observational): plant protein associates with lower all-cause/CVD mortality, animal protein is null, total amount does little — a source-substitution decision, distinct from the muscle-quantity target
- Protein Quality and the DIAAS Score — how protein quality is scored, and whether hitting a target from plant sources costs more food mass and carbohydrate than from animal sources
- Protein Intake and Kidney Function — does higher protein harm the kidneys? Devries 2018 SR-MA: no change in GFR in adults without CKD (the GFR rise is benign kidney functional reserve); the standing objection to a higher target, defused for the healthy — with a hard stratum flip for established CKD
- Protein Intake During Energy Restriction — how much protein retains fat-free mass during a deficit in a resistance-trained adult, and why that target runs higher than the energy-balance one
Supplements — worth taking or not
- Vitamin and Mineral Supplements for Disease Prevention — for a generally-nourished adult, whether vitamins, minerals, multivitamins, or marine omega-3 prevent CVD, cancer, fractures, or death
- Omega-3 Supplementation and Atrial Fibrillation — the harm-channel counterweight: marine omega-3 supplements raise incident-AF risk dose-dependently (overall HR 1.25; >1 g/d 1.49 vs <=1 g/d 1.12)
- Creatine Supplementation — which of creatine’s many claims are established (and which are not), for whom, and at what dose
- Vitamin C and the Common Cold — refuted for general-population incidence (RR 0.97); a real route-(b) exception under heavy acute physical stress (RR 0.48); modest duration effect of regular use only; therapeutic-at-onset unproven
- Vitamin B12 Status in Vegetarian and Vegan Diets — the repletion mirror: a diet-defined shortfall (B12 has no plant source) makes supplementation close to non-optional for vegetarians/vegans; serum B12 is the wrong marker (use MMA/holo-TCII); biochemical deficiency is a surrogate, not held harm