Beneficial Effects on Fatty Acid Composition and Indices of Fatty Acid Desaturase Activity with a Paleolithic-Type Diet during a Two-Year Intervention in Obese Postmenopausal Women

Program: Abstracts - Orals, Poster Previews, and Posters
Session: SUN 572-599-Lipids, Lipoproteins, Dyslipidemia and Fatty Liver Disease (posters)
Basic/Translational
Sunday, April 3, 2016: 1:15 PM-3:15 PM
Exhibit/Poster Hall (BCEC)

Poster Board SUN 575
Caroline Blomquist*1, Elin Chorell1, Mats Ryberg2, Caroline Mellberg3, Christel Larsson4, Bernt Lindahl2, Ulf Riserius5 and Tommy Olsson3
1Umeå University, UMEÅ, Sweden, 2Umeå University, Umeå, Sweden, 3Umeå University, Umea, Sweden, 4University of Gothenburg, Gothenburg, Sweden, 5Uppsala Universtity, Uppsala, Sweden
Objectives:To study diet effects of two defined diets on fatty acid (FA) composition in cholesterol esters (CE) and desaturase activity (DA) in plasma and describe their association to reported intake and changes in insulin resistance (IR) in postmenopausal obese women.

Subjects and methods: Seventy obese postmenopausal women (BMI= 32.6 ±3.4) were randomized to either an ad libitumPaleolithic-type diet (PD) aiming at 30 energy percent (E%) protein, 30 E% carbohydrates and 40 E% fats including a high content of unsaturated FAs, or a low fat diet (LFD) aiming at 15 E% protein, 55 E% carbohydrates and 30 E% fat for 24 months. Anthropometry, 4-day food records, IR and relative FA composition of CEs in plasma were measured at baseline and after six and 24 months. Surrogate measures of DAs were expressed as ratios of CEs: Δ-9 DA=16:1/16:0; Δ-6 DA=18:3n-6/18:2n-6 and Δ-5 DA=20:4n-6/20:3n-6. FA E% intake was correlated with FA composition in CE using Spearman rank correlation coefficient. Further sample comparison modeling was performed using orthogonal partial least squares (OPLS) to elucidate correlation patterns between IR and FAs in CE.

Results:At 24 months the reported intake in the PD group of saturated fatty acids (SFA) decreased with 19% and monounsaturated fatty acids and polyunsaturated fatty acids (PUFA) increased with 47% respectively 71% (all p<0.001). The correlation between reported FA E% intake and FA composition of CE in the PD group was significant for SFA (r=0.31, p=0.003) and PUFA (r=0.42, p<0.001). There were no significant changes in reported intake of FAs and no correlation found to FAs in CE in the LFD group at 24 months. Δ-6 and Δ-9 DA decreased significantly more in the PD group than in the LFD group after 24 months (p=0.002 and p=0.013, respectively). Δ-5 DA increased in both groups at 6 months, significantly more in the PD group (p<0.001). FAs associated to IR including 14:0, 16:1, 18:3n-6 and 20:3n-6 decreased all in the PD group after 24 months (p=0.001; 0.001; 0.014; and 0.0001 for difference between groups). Both diets resulted in a similar reduction in body weight and abdominal height (both p<0.001 within groups) after 24 months. We detected a significant pattern of FAs via the OPLS analysis that was associated to IR with higher levels of 14:0, 15:0, 16:1, 18:0, 18:3n-3 and 20:3n-6 and lower levels of 20:4n-6 and Δ-5 DA; this was more pronounced at 6 months in the PD group. 

Conclusions: The biomarkers for FA intake confirm an increased intake of PUFA (fish) and decreased intake of SFA (dairy products at 6 months) in the PD group. The PD reduced specific FAs (14:0; 16:1; 18:3n-6 and 20:3n-6) and DAs (Δ-9 and Δ-6) associated with IR more distinctly than a LFD during a 24-month diet intervention. The changes in FA levels associated to PD may have long-term beneficial effects on obesity-related disorders.

Nothing to Disclose: CB, EC, MR, CM, CL, BL, UR, TO

*Please take note of The Endocrine Society's News Embargo Policy at https://www.endocrine.org/news-room/endo-annual-meeting/pr-resources-for-endo