Does Vitamin C Make The Body More Acidic?

All foods can be classified as alkaline- or acid-forming in your body based on the cumulative nature of the compounds they produce when metabolized. In general, alkaline-forming foods support a healthy, balanced body pH, while acid-forming foods generate acidic waste products that your body must buffer and remove to maintain homeostasis. A food’s acid content isn’t reflective of its pH nature in your body -- many highly acidic foods, including those rich in vitamin C, are alkaline-forming in your body. Likewise, many low-acid foods are moderately to highly acid-forming in your body.

Vitamin C

The primary function of vitamin C, also known as L-ascorbic acid, is the manufacture of your body’s main protein substance, collagen. Consequently, vitamin C is essential for healthy skin, gums, teeth, bones, tendons, ligaments, cartilage and blood vessels, and it plays an integral role in wound healing and scar formation. Vitamin C is also an important nutritional antioxidant that provides protection against cell-damaging free radicals. Vitamin C may reduce the risk of cancer and cataracts, and it protects against damage caused by pollution and cigarette smoke and boosts immunity, according to the “Encyclopedia of Healing Foods.” The chemical makeup, behavior and bioavailability of the vitamin's natural form is identical to its synthetic form, according to the Linus Pauling Institute.

Acid Content

Vitamin C is highly acidic, according to the book “The Acid-Alkaline Balance Diet.” As an acid, it contributes to the low pH values of the foods in which it naturally occurs. All vegetables and fruits have some vitamin C in them. This L-ascorbic acid content, combined with other common organic acids such as quinic, malic or oxalic acids, are what give nearly all fruits and vegetables acidic pH values. Foods with pH values below 7 and above 4.6, such as cabbage, parsley, papaya and watermelon, are considered low-acid foods. Foods with pH values lower than 4.6 -- including apricots, lemons, limes, tomatoes, mangoes, strawberries and raspberries -- are high-acid foods.

Metabolic Effect

A food’s acid content doesn’t determine its pH nature in your body. Rather, the metabolic process affects whether a food primarily contributes acidic or basic substances to your body. High-protein foods, for example, break down into phosphoric and sulfuric compounds, both of which are highly acidic. Consequently, unaged beef, which has a neutral pH of 7, according to Oklahoma Cooperative Extension Service, is highly acid-forming in your body. Similarly, most fruits and vegetables are rich in potassium citrate, which becomes potassium bicarbonate when metabolized. Potassium and bicarbonate are two important alkalizing substances. Nearly all fruits and vegetables are alkaline-forming in your body, according to “Acid Alkaline Food Guide.” Exceptions include Swiss chard, cranberries, plums and conventionally grown carrots.

Considerations

Fruits and vegetables rich in vitamin C support your body’s natural, slightly alkaline pH by contributing alkalizing substances when digested. Some of the foods highest in vitamin C -- including cantaloupe melon, watermelon, kiwi fruit, citrus fruits, mango, papaya, strawberries, broccoli, parsley, bell peppers, cabbage, sweet potatoes and winter squash -- are among the top most alkaline-forming foods.
Heating and cooking significantly reduces a food’s vitamin C content, as does storing it for long periods. Fresh, uncooked fruits and vegetables at the peak of ripeness provide more vitamin C than their less ripe or overripe counterparts. Likewise, uncooked alkaline-forming fruits and vegetables are more alkalizing when they’re fully ripe but not overripe.