Clinical studies on the hypolipidemic and antioxidant effects of selected natural substances.

BACKGROUND: The average blood levels of cholesterol and triacylglycerol in population are generally considered to be indicators of cardiovascular risk. AIM OF THE STUDY: The aim of our study was to present representative data of selected fractions of blood lipids, and the trend of their levels during the last 35 years in the adult population of Slovakia. RESULTS: This study demonstrates the risk of the elevated average cholesterolaemia and triacylglycerolaemia in men aged 35-39 years and above 60 years, as compared to womens' increased blood level that were detected only in the age group above 60 years. Strong gender differences in HDL-cholesterol were found, women having higher values than men, with these differences fading in the age group above 60 years. The results of two clinical studies present the hypolipemic effects of n-3 polyunsaturated fatty acid in individuals with dyslipidaemia, the hypotriacylglycerolemic effect being dominant (p < 0.001). The hypocholesterolemic effect was less significant (p < 0.05) than in cases when lyophilized powder of the Pleurotus ostreatus was applied (p < 0.01). In both cases, a stabilizing effect on serum HDL-cholesterol had been observed. In case of polyunsaturated fatty acid n-3, its increase was borderline with statistical significance (p = 0.05). CONCLUSION: The study emphasises the necessity of improving the average blood level of lipids in the population of Slovakia and the pertinence of using natural substances with a hypolipemic effect in secondary and even primary prevention of atherosclerosis and its serious complications (Tab. 3, Fig. 4, Ref. 27).

Correlation of carnitine levels to methionine and lysine intake.

Plasma carnitine levels were measured in two alternative nutrition groups--strict vegetarians (vegans) and lactoovovegetarians (vegetarians consuming limited amounts of animal products such as milk products and eggs). The results were compared to an average sample of probands on mixed nutrition (omnivores). Carnitine levels were correlated with the intake of essential amino acids, methionine and lysine (as substrates of its endogenous synthesis), since the intake of carnitine in food is negligible in the alternative nutrition groups (the highest carnitine content is in meat, lower is in milk products, while fruit, cereals and vegetables contain low or no carnitine at all). An average carnitine level in vegans was significantly reduced with hypocarnitinemia present in 52.9% of probands. Similarly, the intake of methionine and lysine was significantly lower in this group due to the exclusive consumption of plant proteins with reduced content of these amino acids. Carnitine level in lactoovovegetarians was also significantly reduced, but the incidence of values below 30 micromol/l was lower than in vegans representing 17.8% vs. 3.3% in omnivores. Intake of methionine and lysine was also significantly reduced in this group, but still higher compared to vegans (73% of protein intake covered by plant proteins). Significant positive correlation of carnitine levels with methionine and lysine intake in alternative nutrition groups indicates that a significant portion of carnitine requirement is covered by endogenous synthesis. Approximately two thirds of carnitine requirement in omnivores comes from exogenous sources. The results demonstrate the risks of alternative nutrition with respect to the intake of essential amino acids, methionine and lysine, and with respect to the intake and biosynthesis of carnitine.

[Comparison of nutrient intake and corresponding biochemical parameters in adolescent vegetarians and non-vegetarians]. / Porovnanie príjmu zivín a odpovedajúcich biochemických parametrov u dospievajúcich vegetariánov a nevegetariánov.

BACKGROUND: In comparison to food habits of non-vegetarians alternative nutrition bears several risks, but it also has beneficial effects. Considering risks represent a significant age aspect. Nutritional risk and protective factors were evaluated in a adolescent group. METHODS AND RESULTS: Food habits of 53 lactoovovegetarians (mean duration of vegetarianism 3.2 y) assessed by analysis of dietary questionnaires were compared to those of 55 nonvegetarians and evaluated with respect to basic biochemical indicators (iron, hemoglobin, calcium, total protein, cholesterol, fatty acids, vitamin A, beta-carotene, vitamin C, vitamin 3). Vegetarians consume less fat, and they have higher intake of plant fat, which is reflected din more favourable lipid levels, i.e. lower risk parameters of atherosclerosis (cholesterol, LDL-cholesterol, atherogenic index, saturated fatty acids) and higher values of factors with antisclerotic effect (32.9% ratio of HDL-cholesterol vs. 30.6% in non-vegetarians, polyunsaturated fatty acids, vitamin E/cholesterol ratio, vitamin C). Total plasma protein levels are balanced in both groups (intake of full value mixture of amino acids from grains, legumes (soya), and mild in vegetarians, similar intake of total proteins with a small difference in plant protein consumption). Iron and calcium absorption is inhibited in vegetarians as a consequence of presence of plant food--physic acid, oxaloacetic acid (20.7% hyposiderinemia vs. 0% in non-vegetarians, high iron intake in both groups, iron from plant sources represented 82% in vegetarian boys and 95% in vegetarian girls, hypocalcemia in 28% of vegetarians vs. 7.3% of non-vegetarians). Vegetarians have significantly higher levels of all antioxidant vitamins. This is result of higher consumption of vegetables, fruit, plant fat and sprouts. Higher intake and higher levels of antioxidants are reflected in significantly lower lipoperoxidation values. CONCLUSIONS: Lactoovovegetarian nutrition represents risk for adolescents if the values of iron and calcium are considered, however it has positive aspects on lipid parameters, protein values, and antioxidant parameters.

[Importance of certain hemostatic indicators as cardiovascular risk factors in type 2 diabetes]. / Význam niektorých hemostatických ukazovatelvov ako kardiovaskulárnych rizík u diabetikov 2. typu.

BACKGROUND: Abnormal levels of some hemostatic factors in patients with type 2 diabetes mellitus are associated with increased risk of severe cardiovascular complications. OBJECTIVES: For the purpose of clinical practice it is necessary to specify most relevant coagulation factor abnormalities pertaining to a particular patient's risk profile (e.g. diabetes duration, his/her lipoprotein profile), since a routine examination to their full extent is in common ambulatory practice hardly manageable. This information is also needed for aiming the efforts to influence them purposefully. METHODS: The investigated group included 42 out-patients with type 2 diabetes mellitus. Selected hemostatic factors and lipoproteins were measured with standard methods. Patients were stratified into terciles based on supposedly causative factors (diabetes duration for vWF and lipoproteins for F VII), these relations being also examined in the whole group using regression analysis. MAIN RESULTS AND CONCLUSIONS: vWF (antigen) plasma concentration mean value in the whole group (in % of reference plasma: 149.917; 95% CI 134.296 to 165.538) was on the upper limit of the normal value reference range (56 to 140), exceeding it distinctly in the tercile III with the longest diabetes duration (vWF mean was 180.115; 95% CI 151.961 to 208.270). The mean in this tercile was also by 42.187 (95% CI of diff. 10.231 to 74.142; sign. level 0.012) higher than in the tercile I with the shortest diabetes duration. These 2 variables significantly correlated (r = 0.345; p = 0.025) also in the whole group. F VII plasma concentration mean values in terciles III with highest triacylglycerol (TAG) or total cholesterol (TCH) serum levels (in %: 129.286, 95% CI 121.117 to 137.455 or 121.071, 95% CI 109.228 to 132.915, respectively; the normal value reference range being 70 to 130) clearly surpassed the analogous values in tercile I by 35.0 (95% CI of diff. 22.793 to 47.207; sign. level < 10(-5)) or by 26.0 (95% CI of diff. 10.815 to 41.185; sign. level 0.002), respectively. There were also positive significant correlations between lipoproteins (TAG, TCH or LDL) and F VII in the whole group (r = 0.697, r = 0.580, r = 0.397; p < 0.0001, p < 0.0001, p = 0.018, respectively). Therefore the estimation of vWF seems to be useful in all diabetic patients and most elevated values are to be expected in long-duration-diabetics. F VII should be cared for especially in patients with concomitantly elevated TAG, TCH or LDL-cholesterol serum levels. (Tab. 6, Fig. 4, Ref. 24.)

[Nutritional risk factors of a vegetarian diet in adult lacto-ovo vegetarians]. / Rizikové nutricné faktory vegetariánskeho stravovania u dospelých laktoovovegetariánov.

Risk nutritional factors of alternative alimentation detected in childhood were evaluated in a group of adult lactoovovegetarians (n = 47). The levels of iron, calcium, zinc, total proteins, gluthatione, plasmatic profile of fatty acids and the lipoperoxidation product in correlation with the values of antioxidative vitamins were studied. The results are compared with mean sample upon mixed nutrition (omnivores n = 42). In both groups were the mean values of iron, calcium and zinc in physiological range, but significantly lower in vegetarians. In the alternative nutrition group was in 21 percent of probands hyposiderinemia detected (vs 5 percent in the omnivores group), in 19 percent of probands hypocalcemia (vs 9 percent) and in 6 percent hypozincemia (vs 0 percent). Full-bodied mixture of milk proteins, egg proteins and vegetable sources in lactoovovegetarians ensured sufficient protein saturation and caused significantly higher level of blood gluthatione (intake also in food). Increased value of fatty acid peroxidation index was not due to increased lipoperoxidation in lactoovovegetarians--significantly lower levels of conjugated fatty acid dienes were determined. This was ensured by sufficient protection by means of essential antioxidants--the levels of vitamins E, C, beta-carotene are in vegetarians significantly higher. These are overtreshold values representing reduced risk of free-radical diseases. Lactoovovegetarians had significantly higher content of linoleic and alpha-linoleic acids in plasma. Values of polyunsaturated fatty acids with C20 and C22 and 3-6 double bonds were similar to values in omnivores. In probands on alternative nutrition with iron deficit was significantly lower activity of delta 6 desaturase determined. (Tab. 3, Ref. 45.)

[Alternative nutrition and glutathione levels]. / Alternatívne stravovanie a hladiny glutatiónu.

BACKGROUND: Low protein quality and quantity is reported to be a possible risk of alternative nutrition. Pulses contain 18-41% of methionine in relation to reference protein, moreover, its content in cereals is by one half lower. Therefore vegetarians and vegans may have an insufficient intake of sulphur-containing amino acids that may subsequently affect glutathione values (precursors of its synthesis). METHODS AND RESULTS: In groups of adults on an alternative diet--lactoovovegetarians (n = 47) and vegans (n = 44) aged 19-62 years with average duration on a vegetarian or vegan diet of 7.6 and 4.9 years, respectively, glutathione levels (GSH) were measured in erythrocytes (spectrophotometrically), as well as the activity of GSH-dependent enzymes. As nutritional control (n = 42) served an average sample of omnivores selected from a group of 489 examined, apparently healthy subjects of the same age range living in the same region. One to low protein intake (56% of RDA) exclusively of plant origin significantly lower levels of total proteins were observed in vegans with a 16% frequency of hypoproteinaemia (vs 0% in omnivores). In comparison to omnivores a significantly lower glutathione level was found (4.28 +/- 0.12 vs 4.84 +/- 0.14 mumol/g Hb, P < 0.01). Lactoovovegetarians because of their protein intake in adequate amounts with a 27% proportion of animal proteins (dairy products, eggs) consume a balanced mixture of amino acids, which is reflected in total protein levels similar to omnivores and significantly higher values of glutathione -5.26 +/- 0.12 mumol/g Hb, P < 0.05 (intake of glutathione in diet, higher consumption of fruit and vegetable in comparison to omnivores). A sufficient supply of glutathione as the substrate for enzymatic reactions of hydrogen peroxide or lipid hydroperoxide catabolism, as well as for detoxication of xenobiotics, was reflected in lactoovovegetarians in a significantly higher activity of glutathione-peroxidase and glutathione-S-transferase in erythrocytes. CONCLUSIONS: Low protein intake exclusively of plant origin, significantly lower protein levels with 16% frequency of hypoproteinaemia, significantly lower glutathione values in blood in comparison to omnivores and lactoovovegetarians confirm the risk of a vegan diet also in adult age.

[The effect of n-3 fatty acid administration on selected indicators of cardiovascular disease risk in patients with type 2 diabetes mellitus]. / Vplyv podávania n-3 mastných kyselín na vybrané ukazovatele kardiovaskulárnych rizík u pacientov s diabetom mellitus II. typu.

BACKGROUND: Serum triacylglycerols (TG), VLDL, HDL, fatty acid and eicosanoid spectrum are among the factors determining the risk of cardiovascular complications in NIDDM. N-3 polyunsaturated fatty acids (PUFA) are expected to have beneficial effects on these factors. In NIDDM patients there have however been previously reported (late 1980s) some adverse effects. OBJECTIVES: Our aim was to verify the effects of n-3 PUFA in NIDDM patients using relatively low dosage. METHODS: The investigated group included 21 NIDDM patients with dyslipoproteinemia type IV. The patients were treated for 28 days with 1.7 g EPA (eicosapentaenoic acid) + 1.15 g DHA (docosahexaenoic acid)/day (10 capsules/day of MAXEPA, Seven Seas U.K.). The lipoproteins were measured using the BIO-LACHEMA kits, the fatty acid spectrum in phospholipids was determined by gas chromatography and prostanoids (after their separation) were measured by RIA methods. MAIN RESULTS AND CONCLUSIONS: After the MAXEPA treatment there has been a strong decrease in TG (p < 0.005) and VLDL (p < 0.002) serum levels, accompanied by a significant increase in HDL (p < 0.02). The final-to-baseline TG ratio in individual patients negatively correlated with the relative percentage of EPA in phospholipids after the treatment (p < 0.03; r = -0.474). There was no significant change in serum total cholesterol, fasting glycaemia and glycosylated hemoglobin. There was a slight, but statistically already significant (p < 0.05), rise in LDL. The relative percentage of EPA, docosapentaenoic acid and DHA in serum phospholipids increased sharply (p < 0.001, p < 0.001, p < 0.001). The increase of n-3 PUFA in individual patients was linked with the decrease in n-6 PUFA (p < 0.001; r = -0.686). The spectrum of the latter has changed also very markedly. The prostacyclin PGI2-to-thromboxane TxA2 ratio increased significantly (p < 0.001). Beneficial effects of n-3 fatty acids have prevailed and this kind of treatment seems very encouraging also in NIDDM patients. The results are logically compatible with other authors' results pattern formed in 1990s. A slight rise in serum LDL needs a more detailed discussion since only its phenotype B ("small dense LDL particles") has been recently found to be atherogenic. (Tab. 2, Fig. 5, Ref. 15.)

Influence of vegetarian and mixed nutrition on selected haematological and biochemical parameters in children.

To evaluate the health and nutritional status of children with two different nutritional habits, the authors examined 26 vegetarians (lacto- and lacto-ovo; an average period of vegetarianism 2.8 years) and 32 individuals on mixed diet (omnivores) in the age range 11-14 years. Vegetarian children had significantly lower erythrocyte number as well as reduced levels of haemoglobin and iron compared to omnivores. The average level of iron did not reach the lower limit of the physiological range and hyposiderinemia was found in 58% of vegetarians vs 9% of omnivores. Reduced iron levels were observed in spite of increased intake of vegetable iron sources and vitamin C (which facilitates the conversion to ferro-form). This reduction can be attributed to the absence of animal iron sources with high utilizability and to lower iron utilization in the presence of phytic acid (higher intake of grains compared to omnivores). The incidence of hypoalbuminemia and hypoproteinemia in vegetarian children was 38 and 12%, respectively, compared to 0% in omnivores. The protein mixture from milk, eggs and vegetable sources is complete, but vegetarian children had significantly reduced intake of milk and dairy products. Favourable lipid and antioxidant parameters in vegetarian children reflect the optimal nutrition composition with respect to the prevention of free radical diseases. Such a nutrition results in significantly lower levels of cholesterol and LDL-cholesterol compared to omnivores and significantly higher and over threshold values of essential antioxidants--vitamin C, vitamin E/cholesterol (more effective protection against LDL oxidation), beta-carotene, vitamin A.

[Nutrition and Crohn's disease]. / Výziva a Crohnova choroba.

The relationships between non-specific inflammatory bowel disease and nutrition is considered. One of the hypotheses holds that environmental factors, especially those in dietary intake, can be the initiators of intestinal inflammation. In this connection authors examined a group of patients suffering from Crohns disease and ulcerative colitis. Results observed in patients with Crohns disease indicate: preferred consumption of flour products, decreased intake of vegetables and fruit, lowered tolerance to milk and milk products, increased sugar consumption, increased proportion of smokers, no differences in diet regimen between nick and healthy subjects. (Tab. 3, Ref. 16.)

[The plasma profile of fatty acids in vegetarians]. / Plazmatický profil mastných kyselín u vegetariánov.

The plasma profile of fatty acids has been observed in 27 vegetarian adults, their age ranging from 20 to 63 years (13 men, 14 women) with the average period of vegetarian dietary pattern being 8.8 years. A third of the men and a half of the women were lacto-vegetarians, the rest of them were lacto-ovo-vegetarians. The contents of saturated and monounsaturated fatty acids insignificantly decreased in vegetarians when compared with non-vegetarians (n = 26, 12 men, 14 women, average group of non-smokers with mixed nutrition). The results of parameters regarded as positive factors in vegetarian diet and effective in prevention of atherosclerosis are as follows: significantly higher values of linoliec acid C 18:2, a significantly higher ratio of linoliec/leic acids C 18:2/C18:1 and insignificantly higher value of linolenic acid C 18:3, together with an unchanged, or moderately decreased contents of poly-unsaturated fatty acids C 20:4 (arachidonic acid) and C 22:6 (n3; docosahexaenoic acid). Further prooxidative-antioxidative parameters were selected in regard to the theoretical anticipation of risk brought about by increased lipoperoxidation in vegetarians (poly-unsaturated fatty acids-substrate of the process) which is significant in the etiology of cardio-vascular and oncologic diseases. Their favourable values (significantly lower plasma contents of conjugated dienes of fatty acids, significantly higher plasma value of vitamin C, Beta-carotene, vitamin E/cholesterol-protection of LDL, vitamin E/triacylglycerols-protection of fatty acids, 3.5 times more significant positive linear correlation of vitamin E/triacylglycerol versus plasma contents of C 18:2) eliminate the risk of increased lipoperoxidation in vegetarians. (Tab. 3, Fig. 1, Ref. 29.)

Plasma fatty acid profile and alternative nutrition.

Plasma profile of fatty acids was examined in a group of children consisting of 7 vegans, 15 lactoovovegetarians and 10 semivegetarians. The children were 11-15 years old and the average period of alternative nutrition was 3.4 years. The results were compared with a group of 19 omnivores that constituted an average sample with respect to biochemical and hematological parameters from a larger study of health and nutritional status of children in Slovakia. Alternative nutrition groups had significantly lower values of saturated fatty acids. The content of oleic acid was identical to omnivores. A significant increase was observed for linoleic and alpha-linolenic (n-3) acids. The dihomo-gamma-linolenic (n-6) acid and arachidonic (n-6) acid values were comparable to omnivores for all alternative nutrition groups. Values of n-3 polyunsaturated fatty acids in lactoovovegetarians were identical to those of omnivores whereas they were significantly increased in semivegetarians consuming fish twice a week. Due to the total exclusion of animal fats from the diet, vegans had significantly reduced values of palmitoleic acid as well as eicosapentaenoic (n-3) acid and docosahexaenoic (n-3) acid resulting in an increased n-6/n-3 ratio. Values of plasma fatty acids found in alternative nutrition groups can be explained by the higher intake of common vegetable oils (high content of linoleic acid), oils rich in alpha-linolenic acid (cereal germs, soybean oil, walnuts), as well as in n-3 polyunsaturated fatty acids (fish). The results of fatty acids (except n-3 in vegans) and other lipid parameters confirm the beneficial effect of vegetarian nutrition in the prevention of cardiovascular diseases.

[Risks and advantages of the vegetarian diet]. / Riziká a prednosti vegetariánskej výzivy.

The authors summarize the health risks and advantages of alternative nutrition-lactovegetarian, lactoovovegetarian and vegan. These dietary patterns involve risk in particular during pregnancy, lactation and for the growing organism. Veganism excluding all foods of animal origin involves the greatest risk. General nutritional principles for the prevention of cardiovascular diseases, oncological diseases and diabetes are fully met by the vegetarian diet. Vegetarians and vegans have low risk factors of atherosclerosis and conversely higher levels of antisclerotic substances. Overthreshold values of essential antioxidants in vegetarians imply a protective action against reactive metabolic oxygen products and toxic products of lipid peroxidation and may reduce the incidence of free radical diseases. The authors also draw attention to some still open problems of vegetarianism (higher n-3 fatty acids, taurine, carnitine). In the conclusion semivegetarianism is evaluated.

Lipid and antioxidant blood levels in vegetarians.

Parameters of lipid metabolism (triacylglycerols TG, cholesterol CH, HDL-CH, LDL-CH, atherogenic index AI, profile of fatty acids) were measured in blood samples of 81 healthy lacto and lacto-ovo vegetarians (42 males, 39 females; age range 19-39 years). The average period of being on a vegetarian diet was 6.2 years. Low levels of TG, CH, LDL-CH, AI and HDL-CH values on the borderline between standard and reduced risk (1.4 mmol.l-1) can be considered as favourable from the atherosclerosis prevention aspect. Compared with non-vegetarians (n = 62), the levels of TG, CH, LDL-CH, and AI are significantly reduced in the vegetarian group. As opposed to non-vegetarians, vegetarians showed a higher total sum of polyunsaturated fatty acids, a significantly higher content of linoleic acid (C 18:2) and linolenic acid (C 18:3), unchanged content of oleic acid (C 18:1), stearic acid (C 18:0) and other polyunsaturated fatty acids. The process of lipoperoxidation (with polyunsaturated fatty acids as substrate) is involved in the etiology of cardiovascular and oncological diseases. Favourable values of prooxidative-antioxidative parameters demonstrated a reduced risk of lipoperoxidation in vegetarians, compared to non-vegetarians (significantly reduced content of conjugated dienes of fatty acids in plasma, significantly higher plasma levels of vitamin C, beta-carotene, vitamin E/cholesterol ratio--and indicator of LDL protection, vitamin E/triacylglycerols ratio--an indicator of fatty acid protection--, selenium and glutathione-peroxidase activity).

Antioxidative levels in two nutritional population groups.

Plasma profile of polyunsaturated fatty acids, conjugated dienes of fatty acids (CD) in plasma, levels of vitamins C, E, A and beta-carotene, as well as plasma levels of trace elements (selenium, zinc, copper) were estimated in a group of 162 healthy lacto-vegetarians and lacto-ovo-vegetarians (non-smokers, aged 30-63 years, average period of vegetarianism was 5 years). When compared to omnivores (n = 159, average sample of non-smokers of the same age range from the same geographic region as the vegetarians), a significantly higher content of linoleic acid C 18:2 and linolenic acid C 18:3 was found in vegetarians. Plasma level of the first product of lipoperoxidation (CD) was significantly reduced in vegetarians compared to omnivores. Levels of essential antioxidative vitamins in plasma were significantly higher in vegetarians (vitamin C, beta-carotene, vitamin A, vitamin E/cholesterol-indicating more effective protection of LDL against oxidation, vitamin E/triacylglycerols and 2.27-fold pronounced the positive linear correlation between vitamin E/triacylglycerols and plasma C 18:2 content-indicating higher protective effect against peroxidation of polyunsaturated fatty acids). Beneficial antioxidative values were complemented by elevated level of selenium as well as copper and zinc values equivalent to omnivores. These results support the positive effect of vegetarianism on the regulation of prooxidative processes. This nutritional habit can thus contribute to reduced risk of free radical diseases such as cancer or cardiovascular diseases.

Diabetic esophageal neuropathy and esophageal changes.

Autonomic neuropathy (AN) is more common than previously presumed. In this paper we focus on these changes in the esophagus, which are the most common but clinically the least symptomatic. We examined 36 non-obese subjects with previously diagnosed peripheral neuropathy with no or only mild subjective complaints. Cardiorespiratory tests revealed signs of AN in 93% of the cases. Cholinergic changes were found in 20 patients, 7 of whom also had adrenergic changes. Radiographic changes included: tertiary spasms in 16.7%, inert esophagus in 5.5%, and gastro-esophageal reflex in 5.5% of patients. Statistically significant differences in the passage rate (P < 0.01) and in the lumen of esophagus (P < 0.001) were also found. Mean values obtained in the control group were considered as baseline.

Levels of lipid peroxidation and antioxidants in vegetarians.

Age dependence of lipid peroxidation levels estimated as conjugated dienes (CD) of plasma fatty acids was investigated in vegetarian and non-vegetarian males and females aged 11-14, 15-18, 19-39 and 40-60 years. The increase of CD levels with age was found in probands on both types of nutrition up to the age of 40 years. In the first three age groups, lipid peroxidation was insignificantly lower in vegetarians when compared to nonvegetarians. The increase of conjugated dienes was on the level of significance (p < 0.05) in the oldest vegetarians vs nonvegetarians. Therefore, content of defense parameters--antioxidative vitamin and enzyme--was estimated in blood of vegetarians aged 40-60 years. Significantly higher levels of vitamin C and catalase activity were found in vegetarians (C-63.6 and 86.5 mumol/l; CAT-1497 and 1313 U/ml for males and females, respectively) when compared to nonvegetarians (C-41.3 and 54.4 mumol/l; CAT-1192 and 1086 U/ml). A significant negative linear correlation (p < 0.001) for CD-C and CD-CAT was found in both sexes of vegetarians and in nonvegetarian females (p < 0.05 for nonvegetarian males). Important finding is a more pronounced in vegetarians (2.5-3.4 times higher slope of regression lines) indicating positive effect of vegetarian nutrition on efficiency of protection system.

Plasma fatty acid profile and prooxidative-antioxidative parameters in vegetarians.

Fatty acid profile in plasma was examined in 12 adult vegetarians (lacto and lacto-ovo) aged 41-63 years with an average period of vegetarian nutrition of 9.8 years. Difference in the content of saturated and monounsaturated fatty acids in vegetarians was insignificant (compared to non-vegetarians). Positive factor of vegetarian nutritional habit with respect to atherosclerosis included significantly elevated content of linoleic acid (C 18:2) and linolenic acid (C 18:3), as well as unchanged or only slightly reduced content of polyunsaturated fatty acids--arachidonic acid (C 20:4) and docosahexaenoic acid (C 22:6, n = 3). Favourable values of prooxidative-antioxidative parameters (significantly reduced content of conjugated dienes of fatty acids in plasma, significantly higher plasma levels of vitamin C, beta-carotene, vitamin E/cholesterol--indicator of LDL protection and vitamin E/triacylglycerols--indicator of fatty acid protection) demonstrated a reduced risk of lipoperoxidation in vegetarians.

Selected vitamins and trace elements in blood of vegetarians.

Selected vitamin (A, C, E, beta-carotene) and trace element (selenium, zinc, copper) levels were estimated in the blood of 67 vegetarian nonsmokers aged 34-60 years. The average period of lacto- or lacto-ovovegetarianism was 6.2 years. The results were compared with those of 75 nonvegetarians of the same age and living in the same region. Vegetarians had significantly higher plasma levels of essential antioxidants: vitamin C, beta-carotene, and vitamin A. A significantly higher molar ratio vitamin E/cholesterol indicates a more effective protection especially of low-density lipoproteins against peroxidation. Oxidation of low-density lipoproteins represents one of the key factors in the pathogenesis of atherosclerosis. The molar ratio vitamin E/total lipids was significantly higher in plasma of vegetarians, demonstrating a more effective protection of polyunsaturated fatty acids against peroxidation. Vegetarians had significantly higher plasma levels of selenium and similar levels of zinc and copper when compared to nonvegetarians. These trace elements are important for the activity of antioxidant enzymes. The results document a beneficial effect of vegetarian nutritional habits on antioxidative parameters and thus on the reduction of cardiovascular diseases and cancer risk. Reactive products of oxygen metabolism and subsequent toxic products of lipid peroxidation play an important role in the etiology of these diseases.

Selected prooxidative - antioxidative parameters in blood of adult vegetarians.

Selected prooxidative - antioxidative parameters (conjugated dienes of fatty acids CD, vitamin C, vitamin E, catalase activity CAT, glutathione peroxidase GSH-Px activity) were investigated in blood of 81 vegetarians aged 20-40 years. The average period of consuming vegetarian food was 3.5 years. The results were compared to corresponding values of non-vegetarians of the same age and from the same geographical region (Bratislava). The levels of conjugated dienes of fatty acids were significantly lower in vegetarians. Significantly higher values of molar ratio vitamin E/cholesterol, vitamin E/triacylglycerols and vitamin E/polyunsaturated fatty acids found in vegetarians imply a higher protective effect against lipid peroxidation - antioxidative status in vegetarians is indicated also by significantly higher levels of vitamin C in plasma, significantly increased catalase activity and insignificantly increased activity of glutathione peroxidase in erythrocytes.