[Truncated abstract] Nitric oxide (NO) is fundamental to cardiovascular health. Components of fruits and vegetables could mediate their cardioprotective effects through NO. Two such dietary components are nitrate and polyphenols. There is mounting evidence that dietary nitrate and polyphenols can alter NO status via distinct pathways. Inorganic nitrate augments NO status through the enterosalivary nitrate-nitrite-NO pathway. Polyphenols may affect NO status through the endogenous L-arginine NO synthase pathway. There are, however, a number of gaps in our knowledge. Four studies were conducted to address some of these gaps. Green leafy vegetables are rich in nitrate. Few epidemiological studies have examined the relationship between nitrate intake and measures of vascular disease. We conducted a cross-sectional analysis of the relationship between dietary nitrate intake and common carotid artery intima-media thickness (CCA-IMT), a surrogate measure of atherosclerosis, in a population of older women (n=1080). Higher nitrate intake was associated with lower maximum CCA-IMT (P = 0.005) and lower mean CCA-IMT (P = 0.011). This relationship remained significant after adjustment for lifestyle and cardiovascular risk factors. Thus, increased dietary nitrate was associated with a lower CCA-IMT independent of other risk factors. These results add weight to the growing body evidence that nitrate rich vegetable intake has vascular benefits. Whether the increase in NO status after dietary nitrate intake is a dose related response is unknown. In addition, of concern is whether use of antibacterial toothpaste will interrupt the enterosalivary nitrate-nitrite-NO pathway negating the beneficial effects of dietary nitrate consumption.
|Qualification||Doctor of Philosophy|
|Publication status||Unpublished - 2012|