A comparison of administering protein alone and protein plus glucose on nitrogen balance

It has been suggested previously that in the fasting state the administration of amino acids alone would be more effective in sparing protein than the administration of amino acids plus small amounts of glucose. In the present study we have examined the effect of administration of amino acids alone (1 g/kg per day) and of the same regimen supplemented with 100 g glucose daily, on the nitrogen balance in 10 subjects, six of whom were obese and four undernourished. Mean cumulative nitrogen balance over a 5-day study period was -12.4 g on amino acids alone and +0.5 g when glucose was added (P less than 0.01). It thus appears that the addition of glucose may be beneficial rather than harmful in subjects receiving amino acid therapy.