People living with chronic conditions often have increased nutrient demands compared to healthy individuals. Under these circumstances, disruptions in metabolic processes, underlying inflammation, oxidative stress, or an inability to meet metabolic demands with current nutrient reserves renders certain nutrients “conditionally essential.”

In a study published this week in Diabetes, Obesity and Metabolism, researchers demonstrated that patients who have type II diabetes had improved glycemic control and blood pressure after 4 months of supplementation with ascorbic acid.

Previous research showed that patients with type II diabetes have lower plasma vitamin C levels; therefore, individuals with a history of prediabetes or diabetes have greater vitamin C requirements. This makes sense, since insulin resistance is associated with chronic low-grade inflammation; there will be increased vitamin C requirements to mitigate oxidative stress. Other factors may contribute to this as well, such as increased vitamin C excretion in those with microalbuminuria, or competition between glucose and vitamin C for uptake into cells.

This study included 31 patients with type II diabetes. It was a randomized cross-over study in which each patient took 500 mg of ascorbic acid twice daily or placebo for a 4-month period. Patients wore glucose monitors for 48 h and consumed standardized meals pre- and post-supplementation. Measurements included postprandial glucose incremental areas under the curve, duration of day in hyper- and hypo-glycemia, average 24 h and daily postprandial glucose concentrations, HbA1c, insulin, blood pressure and oxidative stress.

Ascorbic acid supplementation significantly decreased daily postprandial glucose, postprandial hyperglycemia, and time spent in hyperglycemia. In addition, compared to placebo, systolic and diastolic blood pressure decreased an average of 7 mmHg and 5 mmHg, respectively.

Vitamin C supplementation should be considered in patients with type II diabetes to prevent complications and to support overall health. Previous research demonstrated that vitamin C doses over 200 mg per day significantly reduce glucose concentrations.

Other studies have shown that inositol deficiency is common in patients with insulin resistance. There appears to be a reduced ability to process, metabolize, and effectively use inositol from foods, which is a distinctive characteristic feature of insulin resistance. As a result, the nutritional requirements of these patients may not be met by a simple change in the diet. Inositol should be viewed as a conditionally essential nutrient for these individuals.

The level of nutrient intake that maintains the best possible health varies greatly among different individuals. Lifestyle choices and environmental exposures filtered through genetic predisposition are fundamental factors in the expression of disease, and a successful treatment approach must include an investigation into these factors.