The purpose of this study is to compare the tolerance of two forms of vitamin C in adults with sensitivity to acidic foods.

Inclusion Criteria:

• Healthy as determined by laboratory results and medical history
• Females not of child bearing potential
• Self-reported sensitivity to acidic foods
• Agrees to consume a low vitamin C diet

Exclusion Criteria:

• Pregnant, breastfeeding, or planning to become pregnant during the trial
• Use of medications known to interact with vitamin C or cause epigastric effects
• Use of supplements containing containing vitamin C
• Duodenal ulcer or gastric ulcer, gastritis, hiatus hernia, or gastroesophageal reflux disease (GERD) within past 3 months
• Use of antacids and/or acid suppressors within 4 weeks of randomization
• History of irritable bowel syndrome and related disorders
• Alcohol use > 2 standard alcoholic drinks per day; alcohol or drug abuse within the past year
• History of cardiac disease within the past 6 months
• History of or current diagnosis of cancer
• Uncontrolled hypertension
• Unstable renal and/or liver disease
• History of kidney stones
• Unstable psychiatric disorder
• History of or current immunocompromise
• History of hemoglobinopathies
• Participation in another clinical research trial <30 days
• Abnormal liver function
• Serum creatinine > 1.5 x upper limit of normal (ULN)
• Anemia of any etiology
• Uncontrolled and/or untreated thyroid disorder
• BMI ≥ 35 kg/m2
• Unstable medications <30 days
• Allergy or sensitivity to test article ingredients
• Cognitively impaired and/or unable to give informed consent