Is Vitamin C Buffered derived from corn? Can I take it if I'm sensitive to corn?Updated 2 months ago
Yes, the ascorbic acid used in our Vitamin C Buffered (90 capsules) is typically produced via a fermentation process that uses corn as the starting material.
However, no intact corn is present in the finished ingredient due to the extensive manufacturing and purification processes involved.
Ingredients in Vitamin C Buffered
Our Vitamin C Buffered contains the following active ingredients:
Magnesium ascorbate
Magnesium carbonate
Zinc ascorbate
Potassium ascorbate
Each capsule provides 358mg of vitamin C (448% NRV), along with 62mg magnesium (17% NRV), 14mg zinc (140% NRV), and 14mg potassium (<1% NRV).
How Is Ascorbic Acid Manufactured?
The magnesium ascorbate in our Vitamin C Buffered is manufactured from ascorbic acid, which is produced through an industrial fermentation process.
The manufacturing process involves:
Starting material: D-glucose, typically derived from corn (or other carbohydrate sources such as tapioca)
Fermentation step 1: D-glucose is converted to D-sorbitol, then fermented to L-sorbose using Acetobacter bacteria
Fermentation step 2: L-sorbose is converted to 2-keto-L-gulonic acid (2-KLG) using bacterial fermentation
Chemical conversion: 2-KLG undergoes cyclization (lactonization) to form L-ascorbic acid (vitamin C)
Purification: The ascorbic acid is crystallised, filtered, purified, and milled into a fine powder
This is the standard industrial method used worldwide for vitamin C production, whether described as the Reichstein process or modern two-step fermentation.
Is Corn a Declared Allergen?
No, corn is not one of the 14 major allergens that must be declared under UK/EU labelling regulations (FIC 1169/2011).
The 14 major allergens are:
Cereals containing gluten (wheat, rye, barley, oats, etc.)
Crustaceans
Eggs
Fish
Peanuts
Soybeans
Milk
Tree nuts
Celery
Mustard
Sesame seeds
Sulphur dioxide and sulphites (above 10mg/kg)
Lupin
Because corn is not a mandatory allergen, raw material suppliers are not legally required to state whether corn is present in the final raw material. However, they may indicate if corn has been used as a starting material in the fermentation process.
Is the Final Product Free from Corn?
The manufacturing and purification processes mean that no intact corn protein or intact corn material is present in the finished ingredient.
However, we cannot state that the product is completely free from corn-derived starting materials, as corn (typically in the form of glucose) was used at the beginning of the fermentation process.
Can I Take This If I'm Sensitive to Corn?
If you have a mild corn sensitivity, the highly processed and purified nature of ascorbic acid may mean the product is well-tolerated, as no intact corn protein remains.
However, if you are extremely sensitive to corn or corn-derived materials, we strongly recommend discussing this information with your healthcare practitioner before use to ensure it is appropriate for your individual needs.
Your practitioner can assess:
The level of corn sensitivity or allergy you have
Whether the degree of processing and purification is sufficient for your tolerance
Alternative vitamin C sources if needed (such as whole-food or plant-based vitamin C from acerola, rosehip, or camu camu)
Why Does Metabolics Disclose This Information?
At Metabolics, we are committed to transparency and full disclosure of ingredient sources, even when not legally required.
We believe customers have the right to make informed decisions about their supplement use, particularly when managing allergies, sensitivities, or dietary restrictions.
Are There Corn-Free Vitamin C Alternatives?
Most commercially produced ascorbic acid worldwide is manufactured via fermentation processes that use corn, tapioca, or other carbohydrate sources (such as glucose) as starting materials.
Alternative vitamin C sources may include:
Whole-food vitamin C from acerola cherry, rosehip, camu camu, or amla (Indian gooseberry)
Vitamin C derived from non-corn carbohydrate sources (e.g., tapioca, cassava, or beetroot), though these still undergo similar fermentation processes
If you require a guaranteed corn-free vitamin C supplement, we recommend consulting your healthcare practitioner, who can help identify suitable alternatives based on your specific needs.
Metabolics' Commitment to Quality and Transparency
All Metabolics products are:
Manufactured in our UK cleanroom facility to GMP (Good Manufacturing Practice) standards
Independently tested for identity, purity, quality, and strength at multiple stages of production
Free from unnecessary fillers, binders, coatings, and artificial additives
We regularly update our product labels to reflect changes in legislation, ingredients, or allergen information.
Vitamin C Buffered: Key Benefits
Our Vitamin C Buffered is a gentle, low-acid formula designed for individuals with sensitive stomachs.
Key benefits include:
Immune system support: Enhances function of immune cells and supports immune resilience during and after exercise
Collagen formation: Supports healthy skin, joints, and connective tissue
Energy metabolism: Reduces tiredness and fatigue through carnitine synthesis
Antioxidant protection: Protects cells from oxidative stress and regenerates vitamin E
Iron absorption: Converts plant-based (non-haem) iron into a more absorbable form, especially important for vegetarians
Added magnesium and zinc: Provides synergistic support for muscle function, bone health, cognitive function, and skin integrity
If You Need More Help
Email: [email protected]
Phone: +44 (0) 1380 812799 (Mon–Thurs: 8:30am–5:30pm, Fri: 8:30am–5:00pm)
Visit our Vitamin C Buffered product page for full ingredient and dosage information