Ascorbic acid acceptable daily intake

The amount of S02 added to foods is self-limiting because at levels from 200 to 500 ppm the product may develop an unpleasant off-flavor. The acceptable daily intake (ADI) is set at 1.5 mg/kg body weight. Because large intakes can result from consumption of wine, there have been many studies on reducing the use of S02 in wine making. Although some other compounds (such as sorbic acid and ascorbic acid) may partially replace S02, there is no satisfactory replacement for S02 in wine making. 

The body can absorb about 500 mg of ascorbic acid daily with any excess immediately excreted by the kidneys. Large doses may cause diarrhea or other gastrointestinal disturbances. Damage to the teeth has also been reported. However, no adverse effects have been reported at the levels employed as an antioxidant in foods and pharmaceuticals. The WHO has set an acceptable daily intake of ascorbic acid, potassium ascorbate, and sodium ascorbate, as antioxidants in food, at up to 15mg/kg body-weight in addition to that naturally present in food. ... 

The WHO has set an acceptable daily intake of ascorbic acid, potassium ascorbate, and sodium ascorbate, as antioxidants in food, at up to 15m g body-weight in addition to that naturally present in food. ... 

The minimum vitamin C requirement to prevent the development of scurvy has been found to be 10 mg/day (Hodges et al., 1971). This supply is not sufficient for the provision of acceptable reserves of the vitamin. The intake of 10 mg ascorbic acid per day reflects a plasma concentration of 7.6-14.1 p,mol/liter (0.13-0.24 mg/100 ml), a concentration that is far from tissue saturation. The renal clearance of ascorbic acid rises sharply at a point of 82 xmol/liter (1.4 mg/100 ml). An adequate plasma level of 44 p.mol/liter (0.75 mg/100 ml) can be maintained by a daily supply of 60-75 mg ascorbic acid. The daily amount of ascorbic acid, which is catabolized by the human body, can be calculated to be 60 mg based on a total body pool of ascorbic acid of approximately 1500 mg and a maximum turnover rate of 4%. These data are the scientific basis for the formulation of the above recommendations to meet the physiological needs. Table IV shows the recommended daily vitamin C intake for different population groups from the different societies that issue such recommendations. 

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