EFFECTS OF A DIET RICH IN MACADAMIA NUTS ON CARDIOVASCULAR DISEASE RISK FACTORS

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. Numerous epidemiologic studies have established cardioprotective effects of tree nuts and the legume peanuts. Many clinical studies have been conducted to evaluate the effects of nut consumption on multiple risk factors for cardiovascular disease (CVD), and our research team has considerable experience in studying the effects of nuts on markers of cardiovascular risk (Kris-Etherton, Pearson et al. 1999; Kris-Etherton, Yu-Poth et al. 1999; West, Likos et al. 2002; Zhao, Etherton et al. 2004). In the current medical literature, almonds and walnuts have been studied the most intensively. In contrast, less is known about other nuts, including macadamia nuts. Macadamia nuts are of particular interest because, compared to the other nuts, they have a unique nutrient and fatty acid profile. In particular, they are a rich source of monounsaturated fatty acids, and numerous cardioprotective nutrients including fiber, vitamin E, and plant sterols. Because of this nutrient "package", it is likely that macadamia nut consumption can significantly reduce multiple CVD risk factors, compared to an "average American" diet. Results of a meta-analysis conducted by Garg et al. found that diets high in MUFA vs. high in carbohydrate reduce fasting TG levels by 19%, decrease VLDL-C by 22%, and moderately increase HDL-C without negatively affecting LDL-C. Taken together, the nutrients present in macadamia nuts have been shown previously to have independent beneficial effects on lipid metabolism. This study is designed as a 2 period, 5-week randomized crossover study. Participants will be given all of their food for the diet periods and endpoints will be assessed at the end of each period (lipids, markers of inflammation and oxidative stress, vascular health). Data will be compared between each of the two diet periods.