Also see:
Toxicity of Stored PUFA
Vitamin E Needs Increases with PUFA Consumption and Greater Unsaturation
Israeli Paradox: High Omega -6 Diet Promotes Disease
Protective “Essential Fatty Acid Deficiency”
PUFA Accumulation & Aging
Arachidonic Acid’s Role in Stress and Shock
Saturated and Monousaturated Fatty Acids Selectively Retained by Fat Cells
PUFA Promote Stress Response; Saturated Fats Suppress Stress Response
Your MUFA + PUFA Intakes Determine Your True Vitamin E Requirements – N-3s are the Worst Offenders + Even MUFAs Need Buffering | Tool to Calculate Your Individual Needs
The Dangers of Fat Metabolism and PUFA: Why You Don’t Want to be a Fat Burner
Some studies accumulated orginially by Stephan Guyenet, PhD.
Am J Clin Nutr. 1975 Jun;28(6):577-83.
Recommended dietary allowance for vitamin E: relation to dietary, erythrocyte and adipose tissue linoleate.
Witting LA, Lee L.
The general trend toward increased consumption of polyunsaturated fatty acids is apparent in the linoleate level of adipose tissue (13.0 plus or minus 1.3%) and erythrocyte lipids (14.0 plus or minus 1.9%) in the present group of female undergraduate student volunteers compared to values reported in the early 1960’s. On the basis of the level of linoleate in their diets (19.5 plus or minus 0.8%), it is also apparent that further increases in tissue lipid linoleate levels are to be anticipated, which in turn will result in an increased requirement for vitamin E. It is suggested that adipose tissue linoleate levels in the general population be used as a baseline for the periodic evaluation and revision of the recommended dietary allowance for vitamin E. The recommended dietary allowance could then be phrased in terms of the quantity of vitamin E activity to be consumed per gram linoleate in 100 g adipose tissue fatty acids. A recommendation of 0.6 IU vitamin E activity/g linoleate in 100 g adipose tissue fatty acids is tentatively suggested.
Am J Clin Nutr. 1991 Aug;54(2):340-5.
Fatty acid composition of subcutaneous adipose tissue and diet in postmenopausal US women.
London SJ, Sacks FM, Caesar J, Stampfer MJ, Siguel E, Willett WC.
The distributions of fatty acids in subcutaneous-adipose-tissue aspirates and their relation to intake as assessed by a semiquantitative food-frequency questionnaire were investigated in 115 postmenopausal US women free from cancer. Percentages of fatty acids in adipose tissue were significantly correlated with the percentage of total fat intake for polyunsaturated fatty acids (Spearman correlation = 0.37), n-3 fatty acids of marine origin (Spearman correlation = 0.48), and trans fatty acids (Spearman correlation = 0.51) but not for saturated and monounsaturated fatty acids. Correlations were somewhat stronger in 78 women with stable weight over the 6 mo before fat aspiration. These data suggest that intakes of polyunsaturated fatty acids, including n-3 fatty acids, and trans fatty acids are reflected in the adipose tissue but that intakes of saturated and monounsaturated fatty acids are not. The data also provide further support for the validity of the food-frequency questionnaire in the assessment of fat intake.
Am J Clin Nutr. 1998 Jan;67(1):25-30.
The relation between dietary intake and adipose tissue composition of selected fatty acids in US women.
Garland M, Sacks FM, Colditz GA, Rimm EB, Sampson LA, Willett WC, Hunter DJ.
We compared fatty acid amounts in adipose tissue with fatty acid intake calculated from 2 separate weeks of diet recording and two food-frequency questionnaires for 140 participants in the Nurses’ Health Study. Our results showed that the amounts of polyunsaturated and trans fatty acids in adipose tissue reflect dietary intake and confirm those of previous studies. The correlation between the polyunsaturated fatty acid content of adipose tissue and polyunsaturated fatty acid intake from the average of the two food-frequency questionnaires was 0.40; this correlation for trans fatty acids was also 0.40. Linolenic acid amounts in adipose tissue were also moderately correlated with intake from the average of the food-frequency questionnaires (r = 0.34). An estimate of trans fatty acid intake from vegetable sources correlated much more strongly with adipose trans fatty acids than did an estimate of trans fatty acids from animal sources. Adipose tissue aspirates can be used to indicate intake of exogenous fatty acids.
Am J Epidemiol. 1992 Feb 15;135(4):418-27.
Comparison of measures of fatty acid intake by subcutaneous fat aspirate, food frequency questionnaire, and diet records in a free-living population of US men.
Hunter DJ, Rimm EB, Sacks FM, Stampfer MJ, Colditz GA, Litin LB, Willett WC.
In 1986-1987, the authors assessed the fatty acid intake of 118 Boston-area men, aged 40-75 years, by a semiquantitative food frequency questionnaire administered twice, by two 7-day diet records, and by capillary gas chromatography of subcutaneous fat samples obtained by needle aspirate from the lateral buttock. Spearman correlation coefficients between diet record estimates of fatty acid intake (as a percentage of total fat) and fat aspirate measures (as a percentage of total peak area) were as follows: saturated fat, r = 0.16 (p = 0.09); monounsaturated fat, r = 0.22 (p = 0.01); and polyunsaturated fat, r = 0.49 (p = 0.0001). Spearman correlation coefficients between estimates derived from the food frequency questionnaire were as follows: saturated fat, r = 0.18 ( p = 0.05); monounsaturated fat, r = 0.14 (p = 0.14); polyunsaturated fat, r = 0.50 (p = 0.0001); and eicosapentaenoic acid, r = 0.47 (p = 0.0001). These data confirm that the polyunsaturated and eicosapentaenoic fatty acid content of subcutaneous fat is a measure of dietary intake of these fats. Although diet records are commonly thought to be the “gold standard” method of dietary assessment, the similar correlations observed between the fatty acid composition of adipose tissue and estimates of intake from the food frequency questionnaire and from diet records suggest that these two dietary assessment methods have similar validity in the measurement of polyunsaturated fatty acid intake.
Ann Epidemiol. 2003 Feb;13(2):119-27.
Comparison of adipose tissue fatty acids with dietary fatty acids as measured by 24-hour recall and food frequency questionnaire in Black and White Adventists: the Adventist Health Study.
Knutsen SF, Fraser GE, Beeson WL, Lindsted KD, Shavlik DJ.
PURPOSE:
To calibrate and compare intake of different fats and individual fatty acids as assessed with a food frequency questionnaire (FFQ) against that estimated with (i) a series of dietary recalls and; (ii) the relative fat concentration in an adipose tissue biopsy. The FFQ was specially designed for use in a cohort of Seventh-day Adventists. In preparation for a large cohort study investigating the effect of diet on risk of colon, prostate and breast cancer.
METHODS:
The association of adipose tissue fatty acids and dietary fat intake was assessed in 49 black and 72 white Seventh-day Adventists subjects using 8 different 24-hour recalls, a 200-item food frequency questionnaire (FFQ) and adipose tissue biopsies from each subject.
RESULTS:
Pearson correlation between fatty acids in adipose tissue and dietary intake as assessed by multiple 24-hour recalls were as follows: Linoleic acid: 0.77 in black and 0.71 in white subjects, respectively; Linolenic acid: 0.68 (blacks) and 0.62 (whites); Total Polyunsaturated fat (PUFA): 0.78 (blacks) and 0.70 (whites); Total Monounsaturated fat (MUFA): 0.35 (blacks) and 0.03 (whites); Total Saturated fat (SFA): 0.46 (blacks) and 0.56 (whites). Correlations between fatty acids in adipose tissue and dietary intake as assessed by FFQ were: Linoleic acid: 0.61 (blacks) and 0.52 (whites), respectively; Linolenic acid: 0.29 (blacks) and 0.49 (whites); PUFA: 0.62 (blacks) and 0.53 (whites); MUFA: 0.07 (blacks) and 0.31 (whites), SFA: 0.21 (blacks) and 0.31 (whites).
CONCLUSIONS:
Our study confirms findings of others that 24-hour recalls are valid for assessing dietary intake of different types of fat. The FFQ we developed and used in this study gave reasonably valid measures of fatty acid intake in our population and is thus suitable for use in large cohort studies. It had validity comparable to that observed for other FFQs.
Am J Clin Nutr. 1995 Nov;62(5):956-9.
Biomarkers of habitual fish intake in adipose tissue.
Marckmann P, Lassen A, Haraldsdóttir J, Sandström B.
The association between habitual fish and marine n-3 polyunsaturated fatty acid (PUFA) intake, and the fatty acid composition of subcutaneous fat was studied in 24 healthy young volunteers. Habitual dietary intakes were estimated from three 7-d weighted food records made at months 0, 5, and 8 of the 8-mo study period. The adipose tissue fatty acid composition of each individual was determined by gas chromatography as the mean of two gluteal biopsies, obtained in the first and the last month of the study. The daily consumption of fish and of marine n-3 PUFAs in absolute terms (g/d) was significantly associated with adipose tissue docosahexaenoic acid content (DHA; r = 0.55 and 0.58, respectively, P < 0.001), but not with eicosapentaenoic and docosapentaenoic acid contents. Our study indicates that the adipose tissue DHA content is the biomarker of choice for the assessment of long-term habitual dietary intakes of fish and marine n-3 PUFAs.
Am J Clin Nutr. 2002 Oct;76(4):750-7.
Adipose tissue biomarkers of fatty acid intake.
Baylin A, Kabagambe EK, Siles X, Campos H.
BACKGROUND:
Biomarkers can provide a more accurate measure of long-term intake than can dietary questionnaires.
OBJECTIVE:
The objective was to identify which adipose tissue fatty acids are suitable biomarkers of intake as assessed with a validated food-frequency questionnaire.
DESIGN:
Costa Rican men with a mean (+/- SD) age of 56 +/- 11 y (n = 367) and women aged 60 +/- 10 y (n = 136) completed a 135-item food-frequency questionnaire and provided an adipose tissue sample. Fifty fatty acids were identified by capillary gas chromatography. Correlation coefficients were calculated after adjustment for age, sex, body mass index, and smoking status.
RESULTS:
The best adipose tissue marker for total intake of saturated fatty acids was 15:0 + 17:0 (r = 0.18). Both 15:0 and 17:0 were also the best correlates of dairy product intake (r = 0.31 for each). The diet-adipose tissue correlations for n-3 fatty acids were r = 0.34 for 18:3, r = 0.15 for 20:5, and r = 0.18 for 22:6. Fish intake correlated significantly with these adipose tissue n-3 fatty acids. Dietary and adipose tissue n-6 fatty acids were highly correlated: 18:2 (r = 0.58) and 18:3 (r = 0.24). The best indicators of total trans fatty acid intake were ct18:2n-6 and tc18:2n-6 (r = 0.58 for each); total 18:1 trans fatty acid (r = 0.45) and 16:1 trans fatty acid (r = 0.16) were the next best indicators.
CONCLUSIONS:
Adipose tissue is a suitable biomarker of dietary fatty acid intake, particularly for n-3 and n-6 cis polyunsaturated fatty acids and trans fatty acids. Ideally, adipose tissue and dietary questionnaires should complement, rather than substitute for, each other in epidemiologic studies.
Am J Epidemiol. 1999 Jul 1;150(1):75-87.
Evaluation of a food frequency questionnaire with weighed records, fatty acids, and alpha-tocopherol in adipose tissue and serum.
Andersen LF, Solvoll K, Johansson LR, Salminen I, Aro A, Drevon CA.
The authors examined the validity of a self-administered 180-item food frequency questionnaire in 125 Norwegian men aged 20-55 years who filled in the questionnaire and completed 14-day weighed records in fall 1995 to winter 1995/6. Spearman correlation coefficients between the two measurements ranged from 0.42 for percent of energy from fat to 0.66 for sugar intake (median r = 0.51). On average, 39% of the men were classified in the same quartile with the two methods, and 3% in the opposite quartile. Correlation coefficients between intake of fatty acids estimated from the questionnaire and the relative amounts of fatty acids in adipose tissue were: linoleic acid (18:2, n-6), r = 0.38; alpha-linolenic acid (18:3, n-3), r = 0.42; eicosapentaenoic acid (20:5, n-3), r = 0.52; and docosahexaenoic acid (22:6, n-3), r = 0.49. The correlations for these fatty acids between the total serum lipids and the diet were 0.16, 0.28, 0.51 and 0.52, respectively. The data suggest that very-long-chain n-3 fatty acids in adipose tissue and total serum lipids reflect the dietary intake of very-long-chain n-3 fatty acids to the same degree. No associations were observed between intake of alpha-tocopherol and concentration in adipose tissue and serum.
Am J Clin Nutr. 1990 Sep;52(3):486-90.
Subcutaneous adipose-tissue fatty acids and vitamin E in humans: relation to diet and sampling site.
Schäfer L, Overvad K.
The influence of diet and sampling site on subcutaneous adipose-tissue fatty acid composition and vitamin E content was examined in 20 healthy subjects. A dietary history and adipose-tissue biopsies from the buttock were obtained from 14 individuals. In another six individuals, samples were taken from both waist and buttock. The relative dietary intake of both polyunsaturated and saturated fatty acids correlated with the relative content in adipose tissue (r = 0.6, p = 0.02). Adipose-tissue vitamin E was strongly associated with dietary intake (r = 0.76, p = 0.004). The content of n – 3 (omega-3) fatty acids in adipose tissue was shown to influence adipose-tissue vitamin E negatively. Waist and buttock fat differed (p less than 0.05) with regard to fatty acid composition whereas no systematic variation was seen in the vitamin E content. The use of adipose-tissue biopsies in epidemiologic studies as measures of the habitual relative intake of fatty acids and vitamin E is suggested.
Lipids. 1988 Jun;23(6):598-604.
Biopsy method for human adipose with vitamin E and lipid measurements.
Handelman GJ, Epstein WL, Machlin LJ, van Kuijk FJ, Dratz EA.
An adaptation of the needle biopsy procedure of Beynen and Katan for human adipose tissue, which yields 2-10 mg adipose samples, is described and evaluated. Micromethods are presented for the analysis of alpha-tocopherol, cholesterol and fatty acids in each adipose specimen. The needle biopsy procedure, which uses a Vacutainer to create suction, is compared with a punch biopsy method. The needle biopsy is rapid (6 samples/hr), simple and unobjectionable to the subjects, and provides samples with reproducible ratios of cholesterol and alpha-tocopherol. Unlike the punch biopsy, the needle biopsy reliably obtains specimens with a lipid composition typical of adipocytes. The needle biopsy method is adaptable to nutritional studies of tocopherol and fatty acid metabolism in adipose, and to studies of hazardous compounds stored in adipose. The linoleic acid content of adipose from residents of the West Coast was found to be considerably higher than values reported earlier. The adipose fatty acid data indicate an increase in human adipose linoleate when compared with earlier reports and suggest a trend toward increasing linoleic acid in the American diet.
Am J Clin Nutr. 1985 Dec;42(6):1206-20.
Relationship of diet to the fatty acid composition of human adipose tissue structural and stored lipids.
Field CJ, Angel A, Clandinin MT.
The habitual intake of 20 healthy free-living subjects was determined by two 7-day food records. Documented fatty acid intakes were utilized to examine the influence of fatty acid intake on fatty acid composition of stored and structural lipids in subcutaneous adipose tissue. Subjects with higher intakes of saturated fatty acids exhibited increased levels of total saturated fatty acids and decreased polyunsaturated fatty acids in adipose tissue triglycerides (p less than 0.01). The dietary P/S ratio was significantly related to the saturated and polyunsaturated content of stored lipids. In the phospholipid fraction, relationships were found between dietary C18:2(6) and the P/S ratio of phosphatidylcholine (p less than 0.05). The essential fatty acid content of the two phospholipids studied was related to the dietary fats consumed. Relationships were identified between major fatty acids in the triglyceride and phospholipid fraction. Although diet was found to relate to fatty acid composition, the structural lipids in human adipose tissue appear more resistant to compositional change than stored triglycerides.
Am J Epidemiol. 1986 Mar;123(3):455-63.
Validity of the fatty acid composition of subcutaneous fat tissue microbiopsies as an estimate of the long-term average fatty acid composition of the diet of separate individuals.
van Staveren WA, Deurenberg P, Katan MB, Burema J, de Groot LC, Hoffmans MD.
The relationship between the fatty acid composition of subcutaneous adipose tissue and diet was estimated in 59 Dutch women aged 32-35 years. Food consumption was estimated by taking the means of nineteen 24-hour recalls administered over a period of two and a half years, August 1981-December 1983. Highly significant correlations were found between linoleic acid content of fat tissue and diet (r = 0.70) and also between the linoleic acid-to-saturated fatty acid (linoleic/S) ratio of fat tissue and diet (r = 0.62). This confirms the hypothesis that on an individual level the fatty acid composition of the adipose tissue is a valid index for the habitual dietary fatty acid composition of free-living adults. When using one 24-hour recall instead of the average of 19 recalls, the correlation coefficient between the linoleic/S ratio of the diet and that of the adipose tissue was substantially decreased. This demonstrates the weakening effect of the large day-to-day variation in within-person intake on the correlation between a short-term assessment of the nutrient intake of an individual and a biochemical indicator of long-term nutritional status.
Adv Nutr November 2015 Adv Nutr vol. 6: 660-664, 2015
Increase in Adipose Tissue Linoleic Acid of US Adults in the Last Half Century
Stephan J Guyenet and Susan E Carlson
Linoleic acid (LA) is a bioactive fatty acid with diverse effects on human physiology and pathophysiology. LA is a major dietary fatty acid, and also one of the most abundant fatty acids in adipose tissue, where its concentration reflects dietary intake. Over the last half century in the United States, dietary LA intake has greatly increased as dietary fat sources have shifted toward polyunsaturated seed oils such as soybean oil. We have conducted a systematic literature review of studies reporting the concentration of LA in subcutaneous adipose tissue of US cohorts. Our results indicate that adipose tissue LA has increased by 136% over the last half century and that this increase is highly correlated with an increase in dietary LA intake over the same period of time.
