Ascorbic acid role in containment of the world avian flu pandemic.

In this Comment, the ultimate intent is to increase survival of the anticipated global flu pandemic. The apparent failure of "medicine" to provide a completely understood and logically based biochemical prevention and treatment for all influenzas (and many other viral diseases) may be an unavoidable result of the evolving complexity of the H5N1 virus. However, clinical experience cited in all accounts, including the 2003 to 2006 period, suggest that: (i) ascorbic acid is not being administered to humans infected or at risk for influenza, and (ii) ascorbic acid is (mistakenly) believed to be a vitamin ("vitamin C"). Proper use of ascorbic acid as described here could provide effective containment for the flu pandemic.

Controlling hyperglycemia as an adjunct to cancer therapy.

Hyperglycemia is commonly manifested in cancer patients. Although high intakes of sugar and refined carbohydrates and elevated blood glucose are strongly associated with the risk of cancer, much less is known about their effects on survival after cancer diagnosis. There is evidence that high carbohydrate intake is associated with poorer survival after diagnosis for early breast cancer. We measured glycated hemoglobin in a group of cancer patients (some with active disease and some in remission) and found a statistically significant lower average blood glucose in those in remission. Glycated hemoglobin provides an indication of average blood glucose over 2 to 3 months. The authors discuss lifestyle changes including diet and physical activity that can reduce average blood glucose. Ascorbic acid (AA) supplementation as an adjunct to cancer therapy is also considered. Furthermore, they present a biologically plausible explanation for how hyperglycemia can impair the actions of AA and damage immune effectiveness and hinder cancer survival. One mechanism is likely a reduction in intracellular AA; high intracellular levels of AA are necessary for optimal activity of the hexose monophosphate shunt. This metabolic pathway is important for maintaining proper cellular antioxidant status in immune cells including lymphocytes involved in cell-mediated immunity.

Ascorbic acid, glycation, glycohemoglobin and aging.

The glycation of proteins alters both their structure and function. These changes have been linked to diabetic disorders and aging. The glycation of hemoglobin is also used as a diagnostic tool; the extent of glycation being a reflection of blood glucose averaged over a two to three month period. Accurate measures of average blood sugar (e.g., glycohemoglobin (GHb)) are important in clinical management of diabetes, pregnancy, cancer, etc. Ascorbic acid (AA) can react with proteins, including hemoglobin, and possibly interfere with GHb measurements. Past reports on the impact of AA on in vivo glycation have been equivocal. We studied GHb in subjects supplementing up to 20 g AA daily and found that for each 30 micromol/L increase in plasma AA, GHb was reduced by approximately 0.1. These results suggest that high AA intake can depress glycation, reduce GHb and lead to a clinically relevant underestimation of average blood sugar. Because AA is the most commonly consumed dietary supplement, awareness of an AA-associated bias in GHb is imperative. Of even broader significance is the possibility of AA-mediated inhibition of glycation in all proteins and the implications for aging. Moreover, AA could contribute through several other mechanisms to slowing of human aging (e.g., antioxidant properties, acceleration of pentose phosphate pathway, replacement of structural proteins).