When we say vitamin C is an “essential” vitamin, we’re not just saying it’s important. There’s an actual definition: As mbg’s VP of scientific affairs, Ashley Jordan Ferira, Ph.D., RDN, explains, “the term ‘essential’ here means we must consume vitamin C exogenously (i.e., from diet and supplements) daily because we do not have the physiological ability to produce it endogenously.”
She goes on to share, “while this sounds like a super basic fact–that you need vitamin C every day–in practice, many people treat daily nutrient intake and nutritional sufficiency like something that just magically happens. In reality, it takes thought and effort.”
According to the National Academies, the daily recommended dietary allowance (RDA) for vitamin C is 90 milligrams for men and 75 milligrams for women. Certain individuals–such as women who are pregnant (85 mg) and lactating (120 mg) women–require additional vitamin C each day. These are baseline daily minimums for vitamin C sufficiency.
To put these baseline quantities into perspective, according to the USDA’s nutrient analyses, a whole orange contains 68 milligrams of vitamin C, a whole kiwi contains 64 milligrams, and a whole grapefruit contains 78.6 milligrams.
As for higher vitamin C needs, smokers are estimated to require an additional 35 milligrams of vitamin C daily. Ferira explains, “that’s because, unfortunately, smoking reduces vitamin C levels in your blood and white blood cells. Another reason to strongly consider smoking cessation.”
Additionally, male gender, younger age, body composition (e.g., overweight and obesity), food insecurity, lower income, and even race (black and Mexican American) have been tied to higher risk for vitamin C insufficiency.