Replacing dairy fat with rapeseed oil causes rapid improvement of hyperlipidaemia: a randomized controlled study.

BACKGROUND: Rapeseed oil (RO), also known as canola oil, principally contains the unsaturated fatty acids 18:1n-9, 18:2n-6 and 18:3n-3 and may promote cardiometabolic health. OBJECTIVE: To investigate the effects on lipoprotein profile, factors of coagulation and insulin sensitivity of replacing a diet rich in saturated fat from dairy foods (DF diet) with a diet including RO-based fat (RO diet). DESIGN: During a 2×3-week randomized, controlled, cross-over trial, 20 free-living hyperlipidaemic subjects were provided with isocaloric test diets that differed in fat composition alone. Blood lipoprotein profile, coagulation and fibrinolytic factors and insulin sensitivity (euglycaemic clamp) were determined before and after the dietary intervention. RESULTS: All subjects completed the study, and compliance was high according to changes in serum fatty acids. The RO diet, but not the DF diet, reduced the levels of serum cholesterol (-17%), triglycerides (-20%) and low-density lipoprotein cholesterol (-17%), cholesterol/high-density lipoprotein (HDL) cholesterol ratio (-21%), apolipoprotein (apo) B/apo A-I ratio (-4%) and factor VII coagulant activity (FVIIc) (-5%) from baseline. These changes were significantly different between the diets (P=0.05 to P<0.0001), except for FVIIc (P=0.1). The RO diet, but not the DF diet, modestly increased serum lipoprotein(a) (+6%) and tended to increase the glucose disappearance rate (K-value, +33%). HDL cholesterol, insulin sensitivity, fibrinogen and tissue plasminogen activator inhibitor-1 levels did not change from baseline or differ between the two diets. CONCLUSIONS: In a diet moderately high in total fat, replacing dairy fat with RO causes a rapid and clinically relevant improvement in serum lipoprotein profile including lowering of triglycerides in hyperlipidaemic individuals.

Determination of 2,4,6-trichloroanisole and 2,4,6-tribromoanisole on ng L-1 to pgL-1 levels in wine by solid-phase microextraction and gas chromatography-high-resolution mass spectrometry.

A gas chromatography-high-resolution mass spectrometry (GC-HRMS) method using solid-phase microextraction (SPME) for the determination of 2,4,6-trichloroanisole (TCA) and 2,4,6-tribromoanisole (TBA) in wine at low ng L(-1) levels was developed. A robust SPME method was developed by optimizing several different parameters, including type of fiber, salt addition, sample volume, extraction and desorption time. The quantification limit for TCA and TBA in wine was lowered substantially using GC-HRMS in combination with the optimized SPME method and allowed the detection of low analyte concentrations (ng L(-1)) with good accuracy. Limits of quantification for red wine of 0.3 ng L(-1) for TCA and 0.2 ng L(-1) for TBA with gas chromatography-negative chemical ionization mass spectrometry and 0.03 ng L(-1) for TCA and TBA were achieved using GC-HRMS. The method was applied to 30 wines of which 4 wines were sensorically qualified as cork defected. TCA was found in three of these wines with concentrations in the range 2-25 ng L(-1). TBA was not detected in any of the samples.

A diet containing rapeseed oil-based fats does not increase lipid peroxidation in humans when compared to a diet rich in saturated fatty acids.

OBJECTIVE: To compare the effects of a rapeseed oil-based diet containing an increased proportion of easily oxidised polyunsaturated fatty acids such as alpha-linolenic acid with a diet rich in saturated fatty acids on the degree of lipid peroxidation in the human body. DESIGN: A randomised cross-over study. SUBJECTS AND INTERVENTIONS: Nineteen healthy moderately hyperlipidemic subjects (six women and 13 men, age 50+/-8 y and body mass index (BMI) 24.5+/-2.6 kg/m(2)) were given a rapeseed oil-based diet (RO) and a control diet (SAT) rich in saturated fatty acids during two consecutive 4 week periods separated by a 4 week wash-out period. Biomarkers of lipid peroxidation and antioxidants were analysed in plasma and urine. RESULTS: No significant differences in plasma or urinary levels of free 8-iso-prostaglandin F(2alpha), plasma total 8-iso-prostaglandin F(2alpha) plasma hydroperoxides or plasma malondialdehyde were observed between the RO and SAT diets (P=0.14-0.95). A higher concentration of serum gamma-tocopherol was detected after the RO diet compared to the SAT diet (P<0.001), whereas the serum alpha-tocopherol concentration and plasma antioxidative capacity did not differ between the two test diets. The total cholesterol, LDL cholesterol and LDL/HDL ratio were lower after the RO diet compared to the SAT diet (P<0.001), while HDL cholesterol and total triglyceride levels were similar after the two diets. CONCLUSION: These results suggest that a rapeseed oil-based diet rich in alpha-linolenic acid does not seem to increase the degree of lipid peroxidation in plasma and urine compared to a diet rich in saturated fats. This is possibly due to a sufficient content of antioxidants in the rapeseed oil diet to increase circulating concentrations of antioxidants that may protect unsaturated fatty acids from oxidation. SPONSORSHIP: Swedish Council for Forestry and Agricultural Research and Foundation for Geriatric Research.

Similar effects of rapeseed oil (canola oil) and olive oil in a lipid-lowering diet for patients with hyperlipoproteinemia.

OBJECTIVE: To compare the metabolic effects of a lipid-lowering diet containing either low erucic rapeseed (canola) oil or olive oil. METHODS: Twenty-two hyperlipidemic patients participated in a cross-over study comprising two consecutive 3.5-week treatment periods. The participants were free-living throughout the study period, visiting the metabolic clinic initially and at the end of each treatment period for weighing and blood sampling. All food was prepared daily and weighed out for each individual appropriate to his/her energy requirement. RESULTS: Total serum cholesterol, low-density lipoprotein and the ratio between low-density and high-density lipoprotein cholesterol decreased to the same extent on the two diets tested, as did the apolipoproteins B, A-I and Lp(a). After adjustment for body weight changes, most of the reported effects remained virtually unaltered. However, there was a slightly greater decrease in low-density lipoprotein cholesterol with the diet containing rapeseed oil (-17%, p < 0.001) than with the olive oil diet (-13%, p < 0.01) with p < 0.04 for the difference between diets. Also, the intravenous glucose tolerance improved to a similar extent on both diets. CONCLUSIONS: The results indicate that lipid-lowering diets containing either rapeseed oil or olive oil have similar effects on serum lipoprotein concentration and glucose tolerance in hyperlipidemic subjects.

A diet rich in monounsaturated rapeseed oil reduces the lipoprotein cholesterol concentration and increases the relative content of n-3 fatty acids in serum in hyperlipidemic subjects.

The effects of 3 wk on a diet rich in monounsaturated rapeseed oil were compared with those of a diet containing sunflower oil within a lipid-lowering diet. Ninety-five subjects with moderate hyperlipoproteinemia were randomly assigned to one of the two well-controlled diets prepared at the hospital kitchen. Total serum, low-density- and high-density-lipoprotein cholesterol concentrations decreased by 15%, 16%, and 11% (P < 0.001), respectively, on the rapeseed oil diet and by 16%, 14%, and 13% (P < 0.001) on the sunflower oil diet. Serum triglycerides decreased more markedly (by 29%, P < 0.001) on the sunflower oil than on the rapeseed oil diet (14%, P < 0.01). The n-3 fatty acids (20:5 and 22:5) in the serum phospholipids increased significantly on the rapeseed oil diet but decreased on the sunflower oil diet. There was an increase in the alpha-tocopherol concentrations after both diets. The findings indicate that low erucic acid rapeseed oil can replace oils and fats rich in polyunsaturated fatty acids in a lipid-lowering diet.

Similar serum lipoprotein cholesterol concentrations in healthy subjects on diets enriched with rapeseed and with sunflower oil.

A double-blind cross-over study was conducted during two 3-week periods to compare the effects of rapeseed oil and sunflower oil, enriching a normal diet, on the lipoprotein and fatty acid composition in healthy subjects. It was carried out in randomized order at residential schools, comprising 101 persons (mean age 29.2 years). The dietary fats used for cooking and as table margarine were prepared from rapeseed oil during one period and from sunflower oil during the other. No changes were made in the total fat content or other dietary nutrients. During both treatment periods the serum cholesterol (-4%, P < 0.001), LDL cholesterol (-5% to -7%, P < 0.01 and 0.001) and apolipoprotein B (-5%, P < 0.001) concentrations decreased significantly and to the same extent, while serum triglycerides, HDL cholesterol, apolipoprotein A-1 and lipoprotein (a) remained virtually unchanged. The content of 18:2 n-6 serum phospholipids was increased after the sunflower oil-enriched diet, and the contents of oleic acid (18:1 n-9), alpha-linolenic acid (18:3 n-3), and eicosapentaenoic acid (20:5 n-3) were increased after the rapeseed oil-enriched diet. The concentration of alpha-tocopherol increased and gamma-tocopherol decreased after the sunflower oil-enriched diet, less so after the rapeseed oil-enriched diet. It is concluded that substitution of mono- and polyunsaturated fats for saturated fats without any other dietary changes causes a significant improvement of the lipoprotein profile in healthy subjects. The rapeseed oil and sunflower oil fats were equally effective in this respect. The results also indicate that humans have a certain capacity to elongate and desaturate alpha-linolenic acid to 20:5 n-3 in vivo. Dietary fats based on rapeseed oil seem to be attractive alternatives to the more commonly used oils and fats rich in linoleic acid. Financial support from the Swedish Council for Forestry and Agricultural Research and the Swedish Margarine Industrial Association for Nutritional Physiological Research is gratefully acknowledged.

Similar serum lipoprotein reductions by lipid-lowering diets with different polyunsaturated:saturated fat values.

Lipid-lowering diets enriched in polyunsaturated fat decrease the serum cholesterol in hyperlipoproteinaemia, usually by reducing both the low-density-lipoprotein (LDL) and high-density-lipoprotein (HDL) cholesterol concentrations. The aim of the present study was to investigate whether the effects on LDL could be maintained but those on HDL cholesterol be diminished by reducing the ratio, polyunsaturated:saturated fat (P:S) of the diet. Twenty hyperlipoproteinaemic patients (six with type IIa, eight with type IIb and six with type IV) in a metabolic ward were given two fat-modified diets during two consecutive 3-week periods in a randomized order. The diets were identical with regard to nutrient composition but differed with regard to the P:S values, which were 2.0 and 1.3 respectively. The lipoprotein-lipid composition and serum apolipoprotein concentrations were similar at the end of the two dietary periods in type IIa and type IV patients but in type IIb patients a more pronounced reduction of the LDL-cholesterol concentration by 9% (P less than 0.05) was achieved on the diet with the higher P:S value. The HDL-cholesterol did not differ significantly. The results indicate that increasing the P:S value of lipid-lowering diets from 1.3 to 2.0 does not offer a great advantage with regard to the lipoprotein-lipid reductions achieved in moderate hyperlipoproteinaemia.

A fasting and vegetarian diet treatment trial on chronic inflammatory disorders.

Twenty patients with arthritis and various skin diseases were studied on a metabolic ward during a 2-week period of modified fast followed by a 3-week period of vegetarian diet. During fasting, arthralgia was less intense in many subjects. In some types of skin diseases (pustulosis palmaris et plantaris and atopic eczema) an improvement could be demonstrated during the fast. During the vegan diet, both signs and symptoms returned in most patients, with the exception of some patients with psoriasis who experienced an improvement. The concentrations of lactoferrin in serum reflect the turnover and activity of neutrophil leukocytes. When this protein was initially increased it fell to normal values in most cases. The improvement or impairment of signs and symptoms was related to the lactoferrin levels in serum.

Reduction of high density lipoprotein cholesterol and apoliproprotein A-I concentrations by a lipid-lowering diet.

Nine hyperlipoproteinaemic patients were treated with a serum lipid-lowering diet during 4 weeks in a metabolic ward. The diet contained 35% energy from fat and the ratio between polyunsaturated and saturated fats (the P/S ratio) was 2.0. This treatment caused a reduction of the serum concentrations of the low density lipoprotein cholesterol (Chol) by 17% (P less than 0.01), of the apolipoprotein (apo) B by 27% (P less than 0.01), of high density lipoprotein (HDL) Chol by 15% (P less than 0.05) and of the apo A-I by 9% (P less than 0.02). The apo B/apo A-I ratio decreased by 19% (P less than 0.01). It is suggested that the reduced HLD Chol and apo A-I concentrations may be due to both the qualitative change to more polyunsaturated fats in the diet and to the reduction of the total dietary fat intake.

Pronounced lipoprotein lipid reduction obtained by combined lipid-lowering treatment in patients with atherosclerotic disease.

The feasibility of reducing serum lipoprotein levels in patients with atherosclerotic disease by combining diet, clofibrate and nicotinic acid (niceritrol) has been investigated. An additive lipid-lowering effect of diet and the two drugs was demonstrated. It was possible to reduce the serum triglycerides (TG) in hypertriglyceridaemic patients by 50-60%. This corresponded to a reduction of very low density lipoprotein (VLDL) TG by 73 and 66% in patients with hyperlipoproteinaemia (HLP) type IIB and IV, respectively. In normotriglyceridaemic patients the serum TG concentration decreased by 30-40%. The serum cholesterol (Chol) concentration was reduced by 33% and the low density lipoprotein (LDL) Chol by 37% in HLP type IIA and IIB. The LDL Chol decreased by 32% in normolipoproteinaemic patients and by 21% in HLP type IV. The mean value for serum cholesterol after therapy was in all groups close to 200 mg/100 ml. In hypertriglyceridaemic patients high density lipoprotein (HDL) Chol increased by 18%. Clofibrate and niceritrol differed with regard to the effect on serum lipoprotein concentrations as well as on other metabolic parameters. Niceritrol was significantly more effective than clofibrate in lowering LDL Chol and in increasing HDL Chol. Niceritrol treatment significantly reduced the Chol/TG ratio in VLDL while no such effect was seen during clofibrate administration. The two drugs also showed significantly different effects on the fractional removal rate (K2) of triglyceride-rich lipoproteins as measured by the intravenous fat tolerance test (IVFTT). The K2 was significantly increased by clofibrate but was not affected by niceritrol treatment. The two drugs differed also with regard to the effects on serum uric acid concentration and the liver function tests. The plasma fibrinogen levels and the erythrocyte sedimentation rates were reduced during treatment with both niceritrol and clofibrate. The present study demonstrates that it is possible to obtain substantial reductions of serum lipoprotein concentrations by combining lipid-lowering diet, clofibrate and niceritrol treatment. There was an additive lipid-lowering effect of this treatment and the combination of the two drugs seemed beneficial in regard to certain possible side effects. The impact of a lipid reduction within this range on cardiovascular morbidity and mortality remains to be evaluated.