Objective To compare the effects of essential vs. long chain omega (n)-3 polyunsaturated fatty acids (PUFA) in polycystic ovary syndrome (PCOS). Materials/Methods In this 6-week, prospective, double-blinded, placebo (soybean oil) controlled study, 51 completers received 3.5 g n-3 PUFA/day (essential from flaxseed oil or long chain from fish oil). Anthropometric variables, cardiovascular risk factors and androgens were measured; oral glucose tolerance test (OGTT) and frequently sampled intravenous GTT (FSIVGTT) were conducted at the baseline and 6 wks. Results Between group comparisons showed significant differences in serum triglyceride response (p = 0.0368), while the changes in disposition index (DI) also tended to differ (p = 0.0621). When within group changes (after vs. before intervention) were considered, fish oil and flaxseed oil lowered serum triglyceride (p = 0.0154 and p = 0.0176, respectively). Fish oil increased glucose at 120 min of OGTT (p = 0.0355); decreased Matsuda index (p= 0.0378); and tended to decrease early insulin response during IVGTT (AIRg; p = 0.0871). Soybean oil increased glucose at 30 min (p = 0.0030) and 60 min (p = 0.0121) and AUC for glucose (p = 0.0122) during OGTT; tended to decrease AIRg during IVGTT (p= 0.0848); reduced testosterone (p = 0.0216) and tended to reduce SHBG (p = 0.0858). Fasting glucose, insulin, adiponectin, leptin or hs-CRP did not change with any intervention. Conclusions Long chain vs. essential n-3 PUFA rich oils have distinct metabolic and endocrine effects in PCOS, and therefore they should not be used inter-changeably.

Background/Objectives: Polycystic ovary syndrome (PCOS) is commonly associated with insulin resistance, dyslipidemia and increased inflammation, which all benefit from dietary intake of monounsaturated and n-3 polyunsaturated fatty acids (MUFA and n-3 PUFA). Our goal was to compare the effects of MUFA-rich almonds vs n-3/n-6 PUFA-rich walnuts on metabolic and endocrine parameters in PCOS. Subjects/Methods: Thirty-one PCOS patients randomly received either walnuts or almonds containing 31 g of total fat per day for 6 weeks. At the beginning and at the end, anthropometric parameters, fasting lipids, phospholipid-fatty acids, inflammatory markers, androgens, oral glucose tolerance tests (OGTT) and frequently sampled intravenous-GTT were obtained. Results: Weight remained stable. Within group, walnuts increased the n-3/n-6 essential PUFA in the diet and plasma phospholipids. Walnuts decreased low-density lipoprotein-cholesterol by 6% from 3.76 ± 0.27 to 3.38 ± 0.22 mmol/l (P ¼ 0.05) and apoprotein B by 11% from 0.72 ± 0.04 to 0.64 ± 0.05 g/l (Po0.03). Although almonds also reduced low-density lipoprotein-cholesterol by 10% and apoprotein B by 9%, these were not significant. Walnuts increased insulin response during OGTT by 26% (Po0.02). Both walnuts and almonds increased adiponectin (walnuts from 9.5 ± 1.6 to 11.3 ± 1.8 mg per 100 ml, P ¼ 0.0241; almonds from 10.1 ± 1.5 to 12.2 ± 1.4 mg/dl, P ¼ 0.0262). Walnuts decreased HgBA1 from 5.7 ± 0.1 to 5.5 ± 0.1% (P ¼ 0.0006) with significant intergroup difference from almonds (P ¼ 0.0470). Walnuts increased sex hormone-binding globulin from 38.3±4.1 to 43.1±4.3 nmol/l (P ¼ 0.0038) and almonds reduced free androgen index from 2.6±0.4 to 1.8±0.3 (P ¼ 0.0470). Conclusion: Nut intake exerted beneficial effects on plasma lipids and androgens in PCOS.