Is Ascorbic Acid Bad For You?

Ascorbic acid is the chemical name for vitamin C, an essential dietary nutrient. Ascorbic acid also is used as a food additive. In recommended amounts, ascorbic acid helps keep you healthy and is not bad for you. The safe upper limit of vitamin C intake is 2,000 mg daily. If you consume more than this amount, you may experience side effects. Although the side effects from excess ascorbic acid consumption are uncomfortable, they do not usually pose a threat to your long-term health.

Diarrhea

Excessive intake of ascorbic acid is unlikely to occur from dietary sources alone. If you are taking supplementary vitamin C in large doses, however, you may experience digestive symptoms, including diarrhea. Large amounts of ascorbic acid can overwhelm the capacity of your intestines to absorb this nutrient. Unabsorbed, excess ascorbic acid leads to increased water in your bowels and diarrhea. If you experience diarrhea because of excessive ascorbic acid supplementation, reduce your dosage.

Abdominal Cramps

If you consume too much ascorbic acid, you may develop abdominal cramps. As water accumulates in your bowels because of ascorbic acid overload, spasms and painful cramps often occur. Abdominal cramps associated with ascorbic acid overload typically happen before diarrhea develops. Once the excess ascorbic acid passes in your stool, the abdominal cramps go away --- unless you continue to overload your system.

Increased Kidney Stone Risk

Consuming excess ascorbic acid may increase your risk of forming a kidney stone. How people metabolize excess ascorbic acid varies. In a July 2005 study published in the "Journal of Clinical Nutrition," registered dietitian Linda Massey and colleagues reported that approximately 40 percent of study subjects given 2,000 mg of ascorbic acid daily produced high levels of urinary oxalate, a breakdown product of ascorbic acid. High concentrations of urinary oxalate can lead to the formation of a kidney stone. If you have had a kidney stone, talk with your doctor before taking a vitamin C supplement.

Sources of Ascorbic Acid

Ascorbic acid occurs naturally in high concentrations in a variety of fruits and vegetables, including oranges, grapefruit, sweet peppers, papayas, strawberries, broccoli, Brussels sprouts, peas and kiwis. As a food additive, ascorbic acid helps preserve the color and flavor of food. Foods that may contain added ascorbic acid include cured meats, ready-to-eat cereals, rolled oats, fruit drinks, powdered milk, cheese, sherbet, sorbet, vinegar, mustard, canned fruit and wine. Ascorbic acid overload is highly unlikely to occur from dietary sources alone. High-dose vitamin C supplements are typically the cause of such overload.