Vitamin C Status Correlates with Markers of Metabolic and Cognitive Health in 50-Year-Olds: Findings of the CHALICE Cohort Study

Abstract

A cohort of 50-year-olds from Canterbury, New Zealand (N = 404), representative of midlife adults, undertook comprehensive health and dietary assessments. Fasting plasma vitamin C concentrations (N = 369) and dietary vitamin C intake (N = 250) were determined. The mean plasma vitamin C concentration was 44.2 µmol/L (95% CI 42.4, 46.0); 62% of the cohort had inadequate plasma vitamin C concentrations (i.e., <50 µmol/L), 13% of the cohort had hypovitaminosis C (i.e., <23 µmol/L), and 2.4% had plasma vitamin C concentrations indicating deficiency (i.e., <11 µmol/L). Men had a lower mean plasma vitamin C concentration than women, and a higher percentage of vitamin C inadequacy and deficiency. A higher prevalence of hypovitaminosis C and deficiency was observed in those of lower socio-economic status and in current smokers. Adults with higher vitamin C levels exhibited lower weight, BMI and waist circumference, and better measures of metabolic health, including HbA1c, insulin and triglycerides, all risk factors for type 2 diabetes. Lower levels of mild cognitive impairment were observed in those with the highest plasma vitamin C concentrations. Plasma vitamin C showed a stronger correlation with markers of metabolic health and cognitive impairment than dietary vitamin C.

Optimal Nutritional Status for a Well-Functioning Immune System Is an Important Factor to Protect against Viral Infections

“…Currently, the most commonly used vitamin C cutoff levels are approximately ≤23-28 µmol/L for hypovitaminosis C and ≤11 µmol/L for deficiency [58]. The evidence indicates that vitamin C insufficiency or deficiency is common in low and middle-income countries (e.g., Mexico, Brazil, India), and not uncommon in high income countries (e.g., US, Singapore, New Zealand), particularly in at-risk subpopulations [53,[59][60][61][62][63][64][65][66][67]. Furthermore, the WHO and the Food and Agriculture Organization (FAO) of the United Nations have described that, based on blood markers, vitamin A and iron deficiencies are widespread and of significant global concern [46, 49,50].…”

Una mirada actual de la vitamina C en salud y enfermedad

“…También participa en los procesos de maduración neuronal durante el desarrollo embrionario, en la neurotransmisión y en la inmunomodulación, actúa como antioxidante neuronal y como supresor de la formación del péptido beta-amiloide y de la excitotoxicidad mediada por glutamato 31 . Estudios in vitro y en modelos animales han evidenciado efectos protectores del AA en enfermedades neurodegenerativas, principalmente en Alzheimer y Parkinson, mientras que en personas con déficit cognitivo leve se han encontrado bajos niveles de vitamina C 38,39 .…”

“…Sin embargo, estos alimentos no son comúnmente consumidos en Chile, porque no se producen o no forman parte de nuestra cultura culinaria. Las frutas que presentan mayores concentraciones de vitamina C y que son de uso común en nuestro país se presentan en la tabla 1 54,39 . Existen frutas y vegetales que presentan niveles de vitamina C sobre los 40 mg/100 g de alimento, pero son consumidos cocidos, como la papaya, el brócoli, los repollos bruselas y las espinacas, perdiendo hasta un 90% de su contenido de vitamina C, según método de cocción 55 .…”

Erythrocyte Ascorbate Is a Potential Indicator of Steady-State Plasma Ascorbate Concentrations in Healthy Non-Fasting Individuals

“…A diet severely lacking in vitamin C can result in the deficiency disease scurvy, which is characterised by the breakdown of connective tissue, causing localised bruising and bleeding, and ultimately leading to death [2,3]. Although scurvy is now rarely seen, the inadequate dietary intake of vitamin C is thought to be much more common and hypovitaminosis C (plasma ascorbate concentrations < 23 µmol/L) has been described in up to 15% of individuals [4,5]. These levels are associated with early symptoms of scurvy, such as fatigue and depression [6].…”