The Association between Adipose Tissue N-3 Fatty Acids and Blood Lipids

Research supports the beneficial effects of  n - 3   fatty   acids  ( n - 3  FA) in preventing cardiovascular disease (CVD). However, consensus on the effect of  n - 3  FA on CVD risk factors, like dyslipidemia, is lacking. There are no recent studies that examine the relationship between  adipose   tissue   n - 3  FA (which may reflect long term  fatty  acid intake), and  blood   lipids  in adults, especially in the context of inflammation and abdominal obesity. The purpose of this study was to examine the  association  between  adipose   tissue   n - 3  FA and  blood   lipids .

In this cross-sectional study, secondary data analysis was done utilizing data collected from subjects (n=1011; 66% female, 42% Black; Mean age: 58 years) randomly selected from the Adventist Health Study-2 (AHS-2) cohort (n=96,000) to participate in a calibration sub-study. Multivariable linear regression analysis was done to examine the  association  between  adipose   tissue   n - 3  FA (continuous and/or categorical variables) and fasting triglycerides (TAG), low-density lipoprotein cholesterol (LDL-C), and high-density lipoprotein cholesterol (HDL-C). Stratified analyses by waist circumference and c-reactive protein (CRP) were also done for the  association  between  adipose   tissue   n - 3  FA, and TAG and LDL-C.

Adipose   tissue  α-linolenic acid (ALA) was inversely associated with TAG (β= −0.10; p<0.05). After stratified analysis, the inverse  association  between ALA, and TAG remained for subjects with a normal waist circumference (β= −0.13; p<0.05). ALA was inversely associated with LDL-C in subjects with a normal waist circumference (2 nd  and 3 rd  tertiles of ALA β= −9.27 and −9.22; p<0.05), and in subjects with elevated CRP (2 nd  and 3 rd  tertiles of ALA β= −12.63 and −14.77; p<0.05). There was a positive  association  between ALA and HDL-C (3.18; p<0.05). In terms of  adipose   tissue  eicosapentaenoic acid (EPA) plus docosahexaenoic acid (DHA), an inverse  association  with TAG in subjects with abdominal obesity (β= −0.11; p<0.05), and in subjects with CRP >3 mg/L (β= −0.25; p<0.05) was observed.  Adipose   tissue  EPA+DHA and LDL-C was inversely associated in subjects with a CRP>3 mg/L (3 rd  tertile of EPA+DHA β= −10.95; p<0.05). There no significant  association  between  adipose   tissue  EPA+DHA and HDL-C.

In conclusion,  adipose   tissue   n - 3   fatty   acids  overall has favorable effects on  blood   lipids , but they seem to be influenced by abdominal obesity and state of inflammation which needs to be further explored.