Almonds and Almond Oil Have Similar Effects on Plasma Lipids and LDL Oxidation in Healthy Men and Women

Abstract

Epidemiologic and clinical studies have shown that nut consumption is associated with favorable plasma lipid profiles and reduced cardiovascular risk. These effects may result from their high monounsaturated fat (MUFA) content but nuts contain constituents other than fatty acids that might be cardioprotective. We conducted a study to compare the effects of whole-almond vs. almond oil consumption on plasma lipids and LDL oxidation in healthy men and women. Using a randomized crossover trial design, 22 normolipemic men and women replaced half of their habitual fat (approximately 14% of approximately 29% energy) with either whole almonds (WA) or almond oil (AO) for 6-wk periods. Compliance was ascertained by monitoring dietary intake via biweekly 5-d food records, return of empty almond product packages and weekly meetings with a registered dietitian. Fat replacement with either WA and AO resulted in a 54% increase in percentage of energy as MUFA with declines in both saturated fat and cholesterol intake and no significant changes in total energy, total or polyunsaturated fat intake. The effects of WA and AO on plasma lipids did not differ compared with baseline; plasma triglyceride, total and LDL cholesterol significantly decreased, 14, 4 and 6% respectively, whereas HDL cholesterol increased 6%. Neither treatment affected in vitro LDL oxidizability. We conclude that WA and AO do not differ in their beneficial effects on the plasma lipid variables measured and that this suggests that the favorable effect of almonds is mediated by components in the oil fraction of these nuts.

Effects of hazelnut-enriched diet on plasma cholesterol and lipoprotein profiles in hypercholesterolemic adult men

“…Our results are in agreement with those previously published for other tree nuts (Rajaram et al, 2001;Hyson et al, 2002) and other MUFA-rich foods (Grundy, 1986;Kris-Etherton et al, 1999a). The present study also demonstrated that a high-MUFA-rich diet had the added benefit of not increasing TAG, as the lowcholesterol diets recommended by the American Heart Association tend to do (Ginsberg et al, 1990).…”

“…Incorporation of hazelnut (40 g/day) into human diet favorably altered multiple plasma lipid variables in hypercholesterolemic adult men (Figure 1 and Table 5). Our results are comparable to those reported for other tree nuts such as almond (Hyson et al, 2002), macadamia (Garg et al, 2003), pecan (Rajaram et al, 2001), pistachio (Edwards et al, 1999) and walnut (Zambó n et al, 2000), despite the fact that inclusion of Effects of hazelnut-enriched diet on plasma lipid profiles SM Mercanlıgil et al hazelnut into the human diet in our study was less than half of those reported for other nuts. The intake of SFA generally increases the risk of CHD by increasing the concentrations of total and LDL cholesterol, and Apo B, and increasing the ratios of total/HDL cholesterol and LDL/HDL cholesterol (NRC, 1989).…”

“…It is, therefore, imperative to identify alternative diets that can more effectively modify the plasma lipid profiles, and thus reduce CHD risk. In contrast with a Step I or Step II diet, a MUFA diet tends to raise HDL cholesterol and lower TAG concentrations (Grundy, 1986;Mensink and Katan, 1987;Rajaram et al, 2001;Hyson et al, 2002). In keeping with this evidence, hazelnut that is an excellent source of MUFA (Alasalvar et al, 2003b, c), may help in this respect.…”

“…In contrast, there was no difference between the control diet and the baseline. The significant increase in HDL cholesterol concentrations has been reported after consumption of tree nuts such as hazelnut (Durak et al, 1999), almond (Hyson et al, 2002), pistachio (Edwards et al, 1999) and macadamia (Garg et al, 2003). It can be speculated that the increase in HDL cholesterol might be most likely due to decreased triglycerides, where HDL becomes less of a substrate for catabolism (Tokgözoglu, 1999).…”

“…However, recent epidemiologic and clinical studies suggest that frequent nut consumption is associated with favorable plasma lipid profiles (Durak et al, 1999;Edwards et al, 1999;Kris-Etherton et al, 1999b;Zambó n et al, 2000;Rajaram et al, 2001;Hyson et al, 2002;Garg et al, 2003) and reduced risk of coronary heart disease (CHD), cardiovascular disease (CVD), myocardial infarction, atherosclerosis and other chronic ailments (Fraser et al, 1992;Hu and Stampfer, 1999;Sabaté et al, 2000;Albert et al, 2002;Feldman, 2002). The FDA (2003) has recently authorized a health claim about the relationship between the consumption of nuts and reduced risk of CHD.…”