n-3 Essential fatty acids decrease weight gain in genetically obese mice

1. Lean (ln/ln) and obese (ob/ob) mice were given diets containing a fat source of 100 g evening primrose (Oenothera biennis) oil (fatty acids 18:2n-6, 18:3n-6; EPO) or 100 g cod liver oil (20:5n-3, 22:6n-3; CLO)/kg diet. 2. Weight gain was lower in the ob/ob mice fed on CLO, an effect unrelated to food intake. 3. In the ob/ob mice fed on CLO, thromboxane synthesis by clotting platelets was reduced compared with that in ob/ob mice fed on EPO. 4. The ob/ob CLO-fed mice had lower arachidonic acid but higher levels of n-3 fatty acids in liver, brown adipose tissue and white adipose tissue. 5. The n-3 fatty acids in CLO therefore replaced the n-6 fatty acids in tissue lipids and reduced synthesis of '2 series' prostaglandins in addition to causing lower weight gain in the CLO-fed ob/ob mice.     

Diets containing Sophora japonica L. prevent weight gain in high-fat diet-induced obese mice

Obesity, a worldwide epidemic, is associated with metabolic diseases such as insulin resistance, dyslipidemia, hypertension, and heart disease. Many strategies, including natural alternative antiobesity agents, have been widely used to prevent obesity. Polyphenolic compounds and flavonoids from natural products are shown to inhibit adipogenesis. Because mature fruits of Sophora japonica L. were previously shown to contain antiadipogenic compounds, we hypothesized that diets with mature fruits of S japonica L. would prevent body weight gain in high-fat diet–induced obesity. Four-week-old mice were fed either a control high-fat diet, or high-fat diet containing 1% or 5% of S japonica L. for 4 weeks. The administration of S japonica L. fed in combination with a 30% high-fat diet significantly decreased body weight gain. S japonica L. also reduced serum and hepatic triglyceride, serum total, and high-density lipoprotein cholesterol. Consistent with the effects of lowering glucose level and fat mass, S japonica L. caused a decrease in the number of large adipocytes and a concomitant increase in the number of small adipocytes, which may explain at least in part the antiobesity effects of S japonica L. Together, these data provide evidence for roles of S japonica L. in the control of body weight and obesity-related metabolic diseases.     

Impact of Korean pine nut oil on weight gain and immune responses in high-fat diet-induced obese mice

Korean pine nut oil (PNO) has been reported to have favorable effects on lipid metabolism and appetite control. We investigated whether PNO consumption could influence weight gain, and whether the PNO-induced effect would result in an improvement of immune function in high-fat diet (HFD)-induced obese mice. C57BL/6 mice were fed control diets with 10% energy fat from either PNO or soybean oil (SBO), or HFDs with 45% energy fat from 10% PNO or SBO and 35% lard, 20% PNO or SBO and 25% lard, or 30% PNO or SBO and 15% lard for 12 weeks. The proliferative responses of splenocytes upon stimulation with concanavalin A (Con A) or lipopolysaccharide (LPS), Con A-stimulated production of interleukin (IL)-2 and interferon (IFN)-γ, and LPS-stimulated production of IL-6, IL-1β, and prostaglandin E₂ (PGE₂) by splenocytes were determined. Consumption of HFDs containing PNO resulted in significantly less weight gain (17% less, P < 0.001), and lower weight gain was mainly due to less white adipose tissue (18% less, P = 0.001). The reduction in weight gain did not result in the overall enhancement in splenocyte proliferation. Overall, PNO consumption resulted in a higher production of IL-1β (P = 0.04). Replacement of SBO with PNO had no effect on the production of IL-2, IFN-γ, IL-6, or PGE₂ in mice fed with either the control diets or HFDs. In conclusion, consumption of PNO reduced weight gain in mice fed with HFD, but this effect did not result in the overall improvement in immune responses.     

S 23521 decreases food intake and body weight gain in diet-induced obese rats

OBJECTIVE: To investigate the effect of S 23521, a new glucagon-like peptide-1-(7-36) amide analogue, on food intake and body weight gain in obese rats, as well as on gene expression of several proteins involved in energy homeostasis. RESEARCH METHODS AND PROCEDURES: Lean and diet-induced obese rats were treated with either S 23521 or vehicle. S 23521 was given either intraperitoneally (10 or 100 microg/kg) or subcutaneously (100 microg/kg) for 14 and 20 days, respectively. Because the low-dose treatment did not affect food intake and body weight, the subcutaneous treatment at high dose was selected to test the effect on selected end-points. RESULTS: Treated obese rats significantly decreased their cumulative energy intake in relation to vehicle-treated counterparts (3401 +/- 65 vs. 3898 +/- 72 kcal/kg per 20 days; p < 0.05). Moreover, their body weight gain was reduced by 110%, adiposity was reduced by 20%, and plasma triglyceride levels were reduced by 38%. The treatment also improved glucose tolerance and insulin sensitivity of obese rats. Regarding gene expression, no changes in uncoupling protein-1, uncoupling protein-3, leptin, resistin, and peroxisome proliferator-activated receptor (PPAR)-gamma were observed. DISCUSSION: S 23521 is an effective glucagon-like peptide-1-(7-36) amide analogue, which induced a decrease in energy intake, body weight, and adiposity in a rat model of diet-induced obesity. In addition, the treatment also improved glucose tolerance and insulin sensitivity of obese rats. These results strongly support S 23521 as a putative molecule for the treatment of obesity.     

Tea polyphenols and theaflavins are present in prostate tissue of humans and mice after green and black tea consumption

Green and black tea have shown promise in the chemoprevention of prostate cancer. The objective of this study was to determine the bioavailability and bioactivity of tea polyphenols (PP) and theaflavins in human serum and human and mouse tissues. A decaffeinated black tea diet was administered to C57BL/6 mice. PPs and theaflavins were found in the small and large intestine, liver, and prostate in conjugated and free forms. The relative prostate bioavailability of theaflavin was 70% higher than that of epigallocatechin gallate (EGCG). In the second mouse study, a green tea (GT) diet was administered followed by the control diet for 1-5 d. Epicatechin (EC), EGCG, and epicatechin gallate (ECG) concentrations in prostate tissue were significantly decreased after 1 d of consuming the control diet. Epigallocatechin gallate (EGC), however, did not decrease significantly. For the human study, 20 men scheduled for surgical prostatectomy were randomly assigned to consume 1.42 L daily of GT, BT, or a caffeine-matched soda control (SC) for 5 d before radical prostatectomy. Tea PPs were greater in prostate samples from men consuming BT and GT than in men consuming SC (P = 0.0025). Although tea PP were not detectable in serum, ex vivo LNCaP prostate cancer cell proliferation was less when cells were grown in media containing patient serum collected after BT (P < 0.001) and GT (P = 0.025) consumption relative to baseline serum This is the first human study to show that tea polyphenols and theaflavins are bioavailable in the prostate where they may be active in the prevention of prostate cancer.     

Prevention of diet-induced obesity by dietary black tea polyphenols extract in vitro and in vivo

Objective

The effects of certain tea components on the prevention of obesity in humans have recently been reported, although it is still unclear whether black tea consumption is beneficial. We obtained black tea extract (BTPE) consisting of polyphenols specific to black tea, and from it, prepared a polymerized polyphenol fraction (BTP). The effectiveness of oral administration of the BTPE was examined in in vitro and in vivo experiments.

Methods

Effects of BTPE or BTP on pancreatic lipase activity were investigated in vitro. Male Wistar rats were administered an oral lipid emulsion containing BTPE at a concentration of 500 or 1000 mg/kg body weight and sequential plasma lipid levels were measured. Female C57BL/6N mice were fed a standard or high-fat diet supplemented with 1% or 5% (w/w) BTPE for 8 wk and changes in body weight were examined.

Results

BTP and BTPE inhibited pancreatic lipase activity with an IC₅₀ of 15.5 and 36.4 μg/mL in vitro, respectively. BTPE suppressed increases in rat plasma triglyceride levels in a dose-dependent manner after oral administration of a lipid emulsion. Furthermore, administration of the 5% BTPE suppressed increases in body weight (P < 0.05), parametrial adipose tissue mass, and liver lipid content (reduced to 56.9% and 81.7% of control mice, respectively, P < 0.05) in mice fed a high-fat diet.

Conclusion

The BTPE may prevent diet-induced obesity by inhibiting intestinal lipid absorption. It was suggested that the major active component in the BTPE was BTP.     

Whey protein isolate and glycomacropeptide decrease weight gain and alter body composition in male Wistar rats

The effect of feed protein type on body composition and growth has been examined. Evidence exists that whey protein concentrate is effective at limiting body fat expansion. The presence of caseinomacropeptide, a mixture of glycosylated and non-glycosylated carbohydrate residues, in particular glycomacropeptide (GMP) in whey protein concentrate may be important for this effect. The influence of whey protein isolate (WPI) and GMP on weight gain and body composition was examined by feeding Wistar rats ad libitum for 7 weeks with five semi-purified American Institute of Nutrition-based diets differing in protein type: (1) casein; (2) barbequed beef; (3) control WPI (no GMP); (4) WPI+GMP at 100 g/kg; (5) WPI+GMP at 200 g/kg. Body composition was assessed, and plasma samples were assayed for TAG, insulin and glucose. Body-weight gain was lower (- 21 %) on the control WPI diet relative to casein, with a non-significant influence associated with GMP inclusion (- 30 %), the effect being equivalent at both levels of GMP addition. Renal and carcass fat mass were reduced in the highest GMP diet when compared with WPI (P < 0.05). Plasma insulin was lowered by GMP at the highest addition compared with WPI alone (- 53 %; P < 0.01). Plasma TAG in the WPI+GMP (200 g/kg) group were lower (- 27 %; P < 0.05) than the casein and beef groups. In conclusion, GMP appears to have a significant additional influence when combined with WPI on fat accumulation. WPI alone appears to have the predominant influence accounting for 70 % of the overall effect on body-weight gain. Mechanisms for this effect have not been identified but food intake was not responsible.     

Plasma and tissue levels of tea catechins in rats and mice during chronic consumption of green tea polyphenols

To understand the relationship between tea consumption and its biological effects, plasma and tissue levels of (-)-epigallocatechin-3-gallate (EGCG), (-)-epigallocatechin (EGC), and (-)-epicatechin (EC) were measured after rats and mice were given a 0.6% green tea polyphenol preparation as the drinking fluid for different periods of time. EGC and EC levels in rat plasma increased over time and reached peak values (3 times the Day 1 values) on Day 14. Then the plasma levels of tea catechins decreased, to Day 1 values on Day 28. The plasma concentrations of EGCG were much lower than those of EGC or EC. High levels of EGC and EC were found in urine, whereas high levels of EGCG were found in feces. The changes in the urinary and fecal excretions of tea catechins could not account for the above-described changes in the plasma levels. The amounts of catechins in different tissues reflected the ingestion, absorption, and excretion pattern. When the green tea polyphenol preparation was given to mice, the "increase-and-then-decrease" pattern of catechin levels was also observed in the plasma, lung, and liver; the EGCG levels were much higher than in the rats. The results suggest that consumption of tea by rodents could induce adaptive responses affecting blood and tissue levels of tea catechins with time and that investigation of a similar phenomenon in humans is warranted.     

The efficacy of black tea in ameliorating endothelial function is equivalent to that of green tea

Consumption of tea has been shown to improve endothelial function. It is assumed that catechins are the tea components responsible for these beneficial effects. In black tea, catechin concentrations are significantly lower than in green tea. The present study was designed to compare green and black tea with regard to amelioration of endothelial function. Endothelial function in response to both teas was assessed in bovine aortic endothelial cells (BAEC) and rat aortic rings. To elucidate whether these findings are also applicable to humans, flow-mediated dilation (FMD) and nitro-mediated dilation (NMD) were assessed by ultrasound in twenty-one healthy women before and 2 h after consumption of green and black tea (2 h of FMD and NMD), in comparison with water (control). In BAEC, green and black tea significantly increased endothelial NO synthase activity to the same extent. Similarly, both teas induced comparable endothelial-dependent vasodilation in rat aortic rings. In human subjects, ingestion of green and black tea led to significant increases in FMD: from 5.4 (sd 2.3) to 10.2 (sd 3) % (baseline-adjusted difference (BAD) for 2 h of FMD, green tea v. water: 5.0 (95 % CI 3.0, 7.0) %; P < 0.001) and from 5 (sd 2.6) to 9.1 (sd 3.6) % (BAD for 2 h of FMD, black tea v. water: 4.4 (95 % CI 2.3, 6.5) %; P < 0.001), respectively. The increase in FMD was not significantly different between the two tea preparations (BAD for 2 h of FMD, green tea v. black tea: 0.66 (95 % CI - 0.76, 2.09) %; P = 0.36). NMD did not vary between any of the groups. In conclusion, green and black tea are equally effective in improving endothelial function.     

Theaflavins in black tea and catechins in green tea are equally effective antioxidants

Green tea catechins, including (-)-epicatechin (EC), (-)-epicatechin gallate (ECG), (-)-epigallocatechin (EGC) and (-)-epigallocatechin gallate (EGCG), are oxidized and dimerized during the manufacture of black tea and oolong tea to form orange-red pigments, theaflavins (TF), a mixture of theaflavin (TF1), theaflavin-3-gallate (TF2A), theaflavin-3'-gallate (TF2B) and theaflavin-3,3'-digallate (TF3). The present study was designed to compare the antioxidant activities of individual TF with that of each catechin using human LDL oxidation as a model. All catechins and TF tested inhibited Cu(+2)-mediated LDL oxidation. Analysis of the thiobarbituric acid-reactive substances (TBARS) and conjugated dienes produced during LDL oxidation revealed that the antioxidant activity was in the order: TF3 > ECG > EGCG > or = TF2B > or = TF2A > TF1 > or = EC > EGC. Four TF derivatives also demonstrated a dose-dependent antioxidant activity in Cu(+2)-mediated LDL oxidation at concentrations of 5-40 micromol/L. These results demonstrate that the TF present in black tea possess at least the same antioxidant potency as catechins present in green tea, and that the conversion of catechins to TF during fermentation in making black tea does not alter significantly their free radical-scavenging activity.     

Does diet-induced weight change effect anxiety in overweight and obese adults?

Anxiety is the most prevalent type of mental disorder and a significant health concern. Cross-sectional studies have detected a positive association between obesity and anxiety. What is less clear is whether weight loss can reduce anxiety. We sought to answer three questions:1. Can weight loss improve symptoms of anxiety in the overweight and obese population?2. Does the macronutrient content of energy-restricted diets that induce weight loss affect anxiety?3. Is the change in anxiety related to the amount of weight lost?We investigated the findings from seven interventional studies, which induced weight loss by dietary intervention, in overweight and obese individuals, using established anxiety assessment tools. Mean weight loss ranged from 0.7 to 18.6 kg (SD 4.5) and in three of the studies, anxiety fell by 9.2% to 11.4% and did not change in four studies. When macronutrient content was considered, only one of four interventional studies and one pilot study reported a beneficial effect of a moderate-fat diet on anxiety. There appears to be no strong evidence to indicate that diet-induced weight loss has a beneficial effect on anxiety, however, none of the diet-induced weight loss studies assessed had a detrimental effect on anxiety.     

Anti-inflammatory and anti-diabetic effects of brown seaweeds in high-fat diet-induced obese mice

BACKGROUND/OBJECTIVESSeaweeds have been reported to have various health beneficial effects. In this study, we investigated the potential anti-obesity and anti-inflammatory effects of four types of domestic brown seaweeds in a high-fat diet-induced obese mouse model and bone marrow-derived macrophages (BMDM).MATERIALS/METHODSMale C57BL/6N mice were fed low-fat diet (LFD), high-fat diet (HFD) or HFD containing Undaria Pinnatifida, HFD containing Laminaria Japonica (LJ), HFD containing Sargassum Fulvellum, or HFD containing Hizikia Fusiforme (HF) for 16 weeks.RESULTSBrown seaweed supplementation did not affect long-term HFD-associated changes in body weight or adiposity, although mice fed HFD + LJ or HFD + HF gained slightly less body weight compared with those fed HFD at the beginning of feeding. Despite being obese, mice fed HFD + LJ appeared to show improved insulin sensitivity compared to mice fed HFD. Consistently, we observed significantly reduced blood glucose concentrations in mice fed HFD + LJ compared with those of mice fed HFD. Although no significant differences in adipocyte size were detected among the HFD-fed groups, consumption of seaweeds decreased formation of HFD-induced crown-like structures in gonadal adipose tissue as well as plasma inflammatory cytokines. BMDM from mice fed HFDs with seaweeds showed differential regulation of pro-inflammatory cytokines such as IL-1β and IL-6 compared with BMDM from mice fed HFD by LPS stimulation.CONCLUSIONAlthough seaweed consumption did not prevent long-term HFD-induced obesity in C57BL/6N mice, it reduced insulin resistance (IR) and circulation of pro-inflammatory cytokines. Therefore, seaweeds may ameliorate systemic inflammation and IR in obesity partially due to inhibition of inflammatory signaling in adipose tissue cells as well as bone marrow-derived immune cells.     

Enhancement of erythrocyte antioxidants by green and black tea polyphenols during 7,12-dimethylbenz[a]anthracene-induced hamster buccal pouch carcinogenesis

We evaluated the comparative chemopreventive efficacy of green tea polyphenols (polyphenon-E) and black tea polyphenols (polyphenon-B) on 7,12-dimethylbenz[a]anthracene (DMBA)-induced hamster buccal pouch (HBP) carcinogenesis. Lipid peroxidation, reduced and oxidized glutathione (GSH and GSSG, respectively), and the GSH-dependent enzymes glutathione peroxidase and glutathione S-transferase in the erythrocytes were used as biomarkers of chemoprevention. Enhanced lipid peroxidation in erythrocytes of DMBA-treated animals was accompanied by a significant decrease in the antioxidant status. Dietary administration of polyphenon-E and -B to DMBA-treated animals significantly decreased the extent of lipid peroxidation and enhanced the levels of GSH, GSH/GSSG ratio, and activities of GSH-dependent enzymes. Our study provides evidence that polyphenon-B is more effective in inhibiting HBP carcinogenesis than polyphenon-E by enhancing the antioxidant status, suggesting that polyphenon-B may have a major impact in the chemoprevention of oral cancer.     

Black and green tea polyphenols attenuate blood pressure increases in stroke-prone spontaneously hypertensive rats

Oxidative stress was reported to be involved not only in cardiovascular diseases, but also in hypertension. Epidemiologic studies indicated that tea consumption slightly reduces blood pressure. We conducted two studies to determine whether black and green tea can lower blood pressure (BP) in stroke-prone spontaneously hypertensive rats (SHRSP). Male SHRSP (n=15) were allowed to recover for 2 wk after a transmitter for measuring BP was implanted in the peritoneal cavity. The rats were divided into three groups: the control group consumed tap water (30 mL/d); the black tea polyphenol group (BTP) consumed water containing 3.5 g/L thearubigins, 0.6 g/L theaflavins, 0.5 g/L flavonols and 0.4 g/L catechins; and the green tea polyphenol group (GTP) consumed water containing 3.5 g/L catechins, 0.5 g/L flavonols and 1 g/L polymetric flavonoids. The telemetry system was used to measure BP, which were recorded continuously every 5 min for 24 h. During the daytime, systolic and diastolic BP were significantly lower in the BTP and GTP groups than in the controls. Protein expressions of catalase and phosphorylated myosin light chain (MLC-p) were measured in the aorta by Western blotting. GTP significantly increased catalase expression, and BTP and GTP significantly decreased MLC-p expression in the aorta. These data demonstrate that both black and green tea polyphenols attenuate blood pressure increases through their antioxidant properties in SHRSP. Furthermore, because the amounts of polyphenols used in this experiment correspond to those in approximately 1 L of tea, the regular consumption of black and green tea may also provide some protection against hypertension in humans.     

Inhibition of intestinal tumorigenesis in Apc(min/+) mice by green tea polyphenols (polyphenon E) and individual catechins

In this work, we compared the cancer preventive activities of Polyphenon E (PPE), a standardized green tea polyphenol preparation given in diet versus drinking fluid as well as the activities of PPE versus individual catechins. We treated Apc(Min/+) mice for 9 wk with 0.08% (-)-epigallocatechin-3-gallate (EGCG), 0.08% (-)-epicatechin-3-gallate, or 0.12% PPE in drinking fluid or diet. Only 0.12% dietary PPE and 0.08% EGCG in drinking fluid significantly decreased tumor multiplicity (70% and 51%, respectively). Compared to PPE in drinking fluid, dietary PPE delivered twofold more EGCG to the small intestine. Immunohistochemistry showed that adenomas in groups treated with PPE and EGCG had decreased cell proliferation, Beta -catenin nuclear expression, and phospho-Akt levels; higher cleaved caspase-3 levels, and partially restored retinoid X receptor alpha expression. The results suggest that these molecular events contribute to the cancer prevention activity of EGCG and PPE. Furthermore, diet appears to be a better route of administration for PPE than drinking fluid.     

膳食诱导肥胖小鼠下丘脑Kiss-1和GPR54 mRNA表达

目的探讨Kiss-1/G蛋白偶联受体54(GPR54)基因在肥胖导致雄性小鼠促性腺激素释放激素低下中作用。方法6周龄C57bl/6雄性小鼠,共48只,动物随机分为2组:对照组12只,给予基础饲料,实验组36只,给予高脂饲料,饲养8周后,小鼠按体重分为肥胖倾向(DIO)和肥胖抵抗(DIO-R)2组,下腔静脉抽血后全部断头处死,称量生殖脏器、睾丸周和肾周脂肪含量,电镜检测睾丸间质细胞改变,迅速取出下丘脑组织,检测Kiss-1和GPR54 mRNA表达水平。结果 与对照组比较,DIO组小鼠肾周脂肪、附睾脂肪[(0.59±0.10)、(1.16±0.26)g]及其系数[(0.018±0.002)、(0.036±0.007)]明显升高(P<0.05);DIO组小鼠睾丸系数(0.66±0.08)明显低于对照组(0.77±0.03)(P<0.05);DIO组小鼠下丘脑Kiss-1 mRNA表达水平(0.39±0.07)明显低于对照组(1.00±0.05)(P<0.05)。结论 Kiss-1 mRNA表达降低可能在雄性小鼠促性腺激素释放激素低下中起作用。     

Effects of in vitro vitamin D treatment on function of T cells and autophagy mechanisms in high-fat diet-induced obese mice

BACKGROUND/OBJECTIVESObesity is associated with the impaired regulation of T cells characterized by increased numbers of Th1 and Th17 cells and the dysregulation of vitamin D metabolism. Both obesity and vitamin D have been reported to affect autophagy; however, a limited number of studies have investigated the effects of vitamin D on T cell autophagy in obese mice. Therefore, we aimed to determine whether in vitro treatment with vitamin D affects the proliferation, function, and autophagy of T cells from obese and control mice.MATERIALS/METHODSFive-week-old male C57BL/6 mice were fed control or high-fat diets (10% or 45% kcal fat: CON or HFDs, respectively) for 12 weeks. Purified T cells were stimulated with anti-CD3 and anti-CD28 monoclonal antibodies and cultured with either 10 nM 1,25(OH)₂D₃ or 0.1% ethanol (vehicle control). The proliferative response; expression of CD25, Foxp3, RORγt, and autophagy-related proteins (LC3A/B, SQSTM1/P62, BECLIN-1, ATG12); and the production of interferon (IFN)-γ, interleukin (IL)-4, IL-17A, and IL-10 by T cells were measured.RESULTSCompared with the CON group, T cell proliferation tended to be lower, and the production of IFN-γ was higher in the HFD group. IL-17A production was reduced by 1,25(OH)2D₃ treatment in both groups. The LC3 II/I ratio was higher in the HFD group than the CON group, but P62 did not differ. We observed no effect of vitamin D treatment on T cell autophagy.CONCLUSIONSOur findings suggest that diet-induced obesity may impair the function and inhibit autophagy of T cells, possibly leading to the dysregulation of T cell homeostasis, which may be behind the aggravation of inflammation commonly observed in obesity.     

Changes in abdominal and gluteal adipose-tissue fatty acid compositions in obese subjects after weight gain and weight loss

The fatty acid compositions of abdominal and gluteal subcutaneous adipose tissues of eight obese subjects were measured after an initial 5-10-wk period of weight maintenance on a liquid-formula diet (40% of calories as corn oil, 45% as carbohydrate, and 15% as protein), after a 10% increase in weight (11-20 kg) on a solid-food diet of each subject's choice (n = 5) or after a 20% decrease in weight (26-37 kg) on 800 kcal/d of the same corn-oil-formula diet (n = 5). After weight gain or weight loss, all subjects maintained their new weights for 2-10 wk on the same corn-oil-formula diet. As hypothesized, there were minimal changes in the concentrations of 41 fatty acids identified in both abdominal and gluteal tissues after all dietary phases, and small site-specific differences in the levels of saturated and monounsaturated fatty acids were not altered. The largest change was a 15% decrease (P less than 0.05) in 18:3n-3 in both abdominal and gluteal tissues during weight loss, despite higher levels in the diet than in the baseline adipose tissue. This decrease occurred without coexisting decreases in 22:5n-3 and 22:6n-3, two elongase-desaturase products of 18:3n-3 that were not detectable in the diet.