White blood cell (WBC) counts are among the most routinely ordered labs in clinical practice, and values that fall outside the standard range are often a cause for concern. Leukopenia is defined as a white blood cell count <4,000 cells/µL, while neutropenia refers to an absolute neutrophil count <1,500 cells/µL. Neutrophils make up the largest share of circulating leukocytes and are responsible for engulfing pathogens, so a shortage can weaken immune defenses. Neutropenia can arise from autoimmune conditions, infections, medication side effects, low folate, vitamin B12, or copper, or leukemia, among others. When the cause is unclear, or the counts are severely abnormal, a bone marrow biopsy is often ordered to check whether neutrophil reserves are adequate.
One explanation that often goes unconsidered is benign ethnic neutropenia (BEN), where lower neutrophil counts reflect genetic background rather than disease. On average, people of African descent carry a white blood cell count about 700 cells/µL lower than that of White individuals.
Roughly 4.5% of African Americans and as many as 50% of Africans carry the Duffy-null phenotype, which is linked to malaria resistance and to neutrophil counts that fall below the standard range without any added risk of infection. That discrepancy has led researchers to advocate for separate reference ranges for people with this phenotype, as the standard cutoff does not reflect normal variations across different populations. In any case, for individuals looking to raise their counts, vitamin C is one nutrient with a plausible role in supporting white blood cell production.
Vitamin C is a water-soluble vitamin that supports white blood cell production and concentrates inside neutrophils, where it helps shield them from the oxidative stress generated when they engulf pathogens. It also appears to contribute to the development of B-cells and T-cells, which produce antibodies and coordinate the body's targeted immune response. Most of the literature on vitamin C and low white blood cell counts focuses on intravenous dosing, leaving oral supplementation largely untested. When low counts trace to population variation, oral vitamin C may be a more fitting route to explore than an IV protocol.
However, a recent case report published in Integrative Medicine: A Clinician's Journal followed a 67-year-old African American male who had lived with leukopenia for more than 30 years and also presented with neutropenia. Those findings had sent him for two bone marrow biopsies decades apart, both of which came back normal. He had never had the symptoms that typically accompany low white blood cell counts, such as easy bruising, recurrent infections, fever, or fatigue. Additionally, he reported a healthy lifestyle, going for runs several days per week, eating mostly whole plant foods, meditating regularly, not taking any medications, and occasionally taking vitamin C orally when traveling or feeling a cold coming on.
Routine bloodwork in November 2023 found his white blood cell count at 1,800 cells/µL (reference range 4,000 to 11,000 cells/µL), and his neutrophil count at 730 cells/µL (reference range 1,500 to 8,000 cells/µL), with all other values on his complete blood count in range. His physician referred him to a hematologist for another biopsy to rule out leukemia, which was negative. Having read Linus Pauling's work on vitamin C and wanting to avoid further testing, he asked his nutritionist about using vitamin C to raise his white blood cell count.
The protocol started in March 2024 and combined two forms of vitamin C. Morning and afternoon servings came from vitamin C powder mixed into 10 ounces of water. A liposomal form was used before bed, which spared him from drinking a large volume of fluid at night. A second evening serving was added on days when he felt run down. Over the course of a year, daily intake landed between 5,000 and 7,000 mg, titrated to gastric tolerance.
Follow-up bloodwork was drawn at several points over the following thirteen months, and counts of both total white blood cells (WBC) and absolute neutrophil count (ANC) increased at each check:
By the final assessment, his white blood cell count had nearly doubled and sat just below the standard range, while his neutrophil count had cleared the cutoff and was well within the normal range. He continues on 3,000 mg of oral vitamin C daily.
Dosing at this level raises reasonable questions about tolerance and absorption. The Tolerable Upper Intake Level (UL) is set at 2 g for adults 19+, though the National Institutes of Health (NIH) notes vitamin C carries low toxicity and is not thought to cause serious adverse effects at high intakes. Caution still applies for those with hemochromatosis or a history of hyperoxaluria. Absorption is another consideration, as efficiency drops off well before these amounts and excess spills into the urine once plasma saturates. The combination approach may have helped combat this barrier, as liposomal vitamin C leads to higher circulating concentrations than unencapsulated forms.
Population differences in white blood cell counts shaped this patient's decades-long workup. When clinicians are unaware that lower counts are common among people of African descent, evaluation can extend beyond what the clinical picture calls for, adding unnecessary hardship such as additional testing, financial expense, and time away from work.
As with any single case report, these findings reflect one individual and cannot be generalized without further research. Whether smaller servings would produce the same result is still unknown, and controlled studies are needed to clarify what role oral vitamin C might play in supporting healthy white blood cell production.
Learn more about vitamin C and immune system support:
Immunomodulatory Effects of Vitamins D, E, and C
Vitamin C: Fueling Nitric Oxide for Healthy Blood Vessels
Acerola Fruit: Promoting Vitamin C Status and Absorption
The Role of Phytonutrient-Rich Superfoods in Immune, Brain, and Heart Health
By Jesse Martin, MS
Designs for Health has been dedicated to being the most trusted source for superior quality, science-based nutritional products for nearly three decades. We’re committed to maximizing successful health outcomes by providing healthcare practitioners with comprehensive support through our extensive product line, ongoing clinical education, and practice development programs. The blogs we publish here cover a range of topics, including new and original approaches to diet and healthcare, analyses of the latest cutting-edge research, deep-dives into specific nutrients, botanicals, nutraceuticals and more, all fully referenced for those who want to dig deeper into the primary literature.
