Daily nutritional requirements

Vivian Imbriotis | June 22, 2026

Macronutrients

  • CHOs \(\to\) 4kCal/g, Prot \(\to\) 4kCal/g, fats \(\to\) 9kCal/g
  • Resting energy expenditure (REE) = energy required for resting individual = 21-25kCal/kg/day \(\approx\) 1kCal/kg/hr = 1,700kCal/day for a spherical frictionless 70kg adult.
  • Protein requirements 0.8g/kg/day = 55g at 70kg \(\to\) provides 200kCal/day \(\to\) 1,500kCal/day must be provided by fats and CHOs. Must also provide all 9 essential amino acids.
  • In ICU, protein requirements increased to 1.5g/kg/day
  • ~30% of remaining REE should come from fats \(\to\) 50g/day. Must provide sufficient omega-3 and omega-6.
  • ~70% should come from CHOs \(\to\) 260g/day

Micronutrients

  • Vitamins (essential organic compound body cannot synthesize in sufficient quantity). Fat soluble (ADEK), water soluble (vitamin C, B complex - B1,2,3,5,6,7,9,12).
  • Minerals (essential inorganic compound body cannot synthesize). Na 2mmol/kg = 140mmol/day, K 1mmol/kg = 70mmol/day
  • Ca and PO4 ~0.4mmol/kg = 30mmol/day
  • Mg ~0.2mmol/kg = 15mmol/day
  • Trace elements (Fe, Zn, Cu, iodine etc) small amounts

Water

  • 30ml/kg \(\to\) 2.1L/day