VegPoster presentations
Section IV: Biochemical / Clinical Outcome
LIPOPROTEIN (a) INCREASED O
N VEGAN-TYPE DIET AND POWDERED SOY MILK. James Blankenship 1, Milton Crane 2,3, Thomas Mullen 3, Ronald Gregory 3, Richard Lukens 3, Clyde Sample 3 . I School of Public Health, 2 Department of Medicine, Loma Linda University School of Medicine Loma LindaUniversity, Loma Linda, CA. 3Department of Medicine, Weimar Institute, Weimar, CA 95736Lipoprotein(a) [Lp(a)] was measured in four groups of ambulatory adults ages 17 to 94 at our lifestyle enhancement center for chronic degenerative diseases because of our preliminary evidence that soy milks made of soy protein isolate included in our basic total vegetarian diet of unrefined foods was associated with an elevated Lp(a) as measured by enzyme irnmunoassay on fasting serum samples. The tested groups consisted of the following:
Group 1: 72 on a total vegetarian diet (TV) who had routinely, for a year or more avoided all foods which had free (added) fats, sugar, and other refined ingredients. Group 2: 27 on the same T.V. diet as group 1, but whose diet usually included 150 to 500 ml/day of a commercial soy milk from one of three different companies PRISM) consisting of varying proportions of oil, sugar, and soy protein isolate. Group 3: 56 on an ad lib lacto-ovo-vegetarian diet, for over 2 years. Group 4: 146 on an ad lib omnivore diet (OMNI) for most of their lives.
The average (S.D.) for Lp(a) values in mg/dl) were:
Group 1. TV diet without PSM: Lp(a) was 6.9±5.3 mg/dl. (only 3 of the 72 had Lp(a) values over 15 mg).
Group 2. TV diet with PSM: Lp(a) was 19.6± 16.6 mg/dl. (13 of the 27 had Lp(a) over 15 mg/dl).
Group 3. LOVdiet: Lp(a) was 24.3±26.7. (31of the 56 were over l5mg/dl).
Group 4. Omni diet was 20.4±26.7. (59 of the 146 had Lp(a) values over 15 mg/dl).
The mean values of Group 2, 3, and 4 was significantly above the mean of Group 1 (p= <0.005). We conclude that powdered soy milk significantly increases the Lp(a) and should be excluded from the diet.
(Funded by the Donald and Barbara Cox Research Fund.)
TOTAL VEGETARIAN DIET OF UNREFINED FOODS LOWERS LIPOPROTEIN(a). Milton Crane 1,2, James Blankenship 3, Thomas Mullen', Ronald Gregory l, Richard Lukens 1, Clyde Sample l, 1Department of Medicine, Weimar Institute, Weimar, CA 95736,2 Department of Medicine, Loma Linda University School of Medicine, and 3 School of Public Health, Loma Linda University, Loma Linda, CA.
It is generally reported that diet has little or no effect on Lp(a). Serum lipids and Lp(a) (by enzyme immunoassay) were measured on 209 ambulatory adults ages 18 to 94 on entry into our 18-day live-in livestyle intervention program. Volunteer subjects were divided on entry into two groups on the basis of their food frequency history (otherwise unselected). Sixty (ave. Age 60 yrs) had been on an ad lib lacto-ovo-vegetarian (LOV), and 146 (ave. Age 59 yrs) had been on an ad lib omnivore (OMNI) diet for over a year. The Lp(a) and serum lipids were repeated after two weeks on the program for comparative analysis. The cafeteria prepared meals for all was a total vegetarian, low fat (10 to 22% of cal. from fat), high fiber diet which eliminated all animal products and refined foods. The average values (mg%±SD) for the initial (entry) serum Lp(a), cholesterol, and triglyceride for the LOV group were 27.4±13, 208±38, 182±98 mg%, respectively. The corresponding values for the initial serum Lp(a), cholesterol, and triglyceride for the OMNI group were 20.9±26, 220±54, 219±156 mg%, respectively. (Because of the known analytical variance for Lp(a), we excluded the results of 11.7% of the LOV and 12.1% of the OMNI groups with an initial Lp(a) value of <3 mg% in the calculation of the mean percent change in Lp(a). For the LOV group the mean percent changes in Lp(a), cholesterol and triglyceride on the program were -11±24, -10±8.8 and -7.2±23 percent respectively. Statistically, the mean percent decreases in Lp(a), in cholesterol, and in triglyceride from two weeks on the program were significantly (p<0.003) lower for both the LOV and the OMNI groups.
We conclude that the avoidance of free (added) fat, powdered soy milk, and other refined food lowers the Lp(a) significantly by 10 to 15% in two weeks. Further, the mean percent changes in Lp(a) were essentially the same whether their initial Lp(a) was in the three subgroups: for the 3 to 10 mg% range, for the 11 to 20 range, in for the >20 range.
(Funded by the Donald and Barbara Cox Research Fund.)
INFLUENCE OF ORAL CREATINE SUPPLEMENTATION ON TORQUE PRODUCTION IN A VEGETARIAN AND NON-VEGETARIAN POPULATION. Peter Clarys, Evert Zinzen, Marcel Hebbelinck and Marc Verlinden. Faculty of Physical Education and Physiotherapy, Vrije Universiteit Brussel, Brussels, BELGIUM
Creatine (methylguanidine-acetetic acid) plays an important role in muscular contraction. Creatine is endogeneously synthesized from arginine and glycine in the liver, pancreas and kidney while the diet can be seen as an exogeneous source in omnivores since meat can contain up to 10 g creatine/kg. The vegetarian lifestyle of athletes is often questioned since the absence of exogenous creatine is supposed to lead to lower muscular creatine and hence poor performance in high intensity exercise. The purpose of the present study was to investigate whether peak power torque is lower in vegetarians compared to non-vegetarians and whether oral creatine supplementation affects torque production and reduces short term muscular fatigue in a vegetarian and non-vegetarian population as tested on an isokinetic dynamometer. A group of vegetarian (n=12) and non-vegetarian volunteers (n=12) matched for age, gender and lifestyle, participated in the study. The subjects received oral creatine supplementation (20 g creatine during 6 days) and placebo in a randomized double blind cross-over design. Isolated as well as repeated bouts of contractions were found to produce similar torque outputs in vegetarians and non-vegetarians. Oral creatine supplementation provoked no increase of torque output during isolated nor during repeated bouts of maximal exercise in the vegetarian as well as in the non-vegetarian group. It was indicated that the fatigue index did not differ between the two test populations.
(This study was supported by a grant of the Isostar Sport Nutrition Foundation, Bern, Switzerland)
COMPARISON OF THE EFFECT OF VARIATIONS IN DIETARY PURINE ON THE RISK OF URIC ACID STONE FORMATION. Roswitha Siener, Albrecht Hesse. Division of Experimental Urology, Department of Urology, University of Bonn, Bonn, GERMANY
About 10 - 15 % of all urinary stones are uric acid stones. A high uric acid excretion, a low urinary volume and pH value have been suggested to be the most important risk factors for the formation of uric acid stones. In the present study we examined the effect of three diets with different purine content on the risk of uric acid stone formation.
Ten healthy male individuals received three different standard diets for five days each. Diet 1 corresponded to the usual german dietary habits of healthy men at the age of 19 to 35 years. Characteristic therefore is a high energy, alcohol and purine intake, an excess of protein and a very low fluid intake (1.5 l/d). On the contrary, diet 2 (mixed diet) and diet 3 (ovo-lacto-vegetarian diet) were established according to the dietary recommendations of the German Society of Nutrition. Diet 2 and diet 3 were isoenergetic with equal amounts of the main nutrients and a fluid intake of 2.5 1/d. In the course of the test period, 24 h urine samples were collected. Urinary supersaturation with uric acid was estimated by the computer program EQUIL.
The risk of uric acid stone formation was highest on diet 1, due to the low urinary volume and pH and the high urinary uric acid excretion. On diet 2, relative supersaturation with uric acid was significantly reduced by 85 %, consequent to the decrease of uric acid excretion and concentration and the increase of urinary pH value. The intake of diet 3 led to a funkier significant decline in the risk of uric acid stone formation by
55% compared to diet 2.
These results indicate that the intake of a balanced ovo-lacto-vegetarian diet with a low animal protein and purine content and a high fluid intake leads to the lowest risk of uric acid stone formation.
PLANT-BASED ALPHA-LINOLENIC ACID IN SERUM CHOLESTEROL ESTERS: EFFECT ON 3 EICOSANOIDS. Karen B. Jaceldo, Joan Sabaté, Synnove F. Knutsen, Departments of Nutrition and Epidemiology, Loma Linda University, Loma Linda, CA, USA.
Increased levels of -3 eicosanoids have been associated with improved cardiovascular disease outcomes. Walnuts contain high concentrations (12% of total fat) of the -3 fatty acid, -linolenic acid. In a previous study, we examined the cholesterol-lowering effect of a diet containing 20% of energy from walnuts (Sabaté et al. NEJM 1993;328:603-7). This present investigation assessed the availability of -linolenic acid [LNA, 18:3(n-3)] in serum cholesterol esters for further metabolism to eicosapentaenoic acid [EPA, 20:5(n-3)] and docosahexaenoic acid [DHA, 22:6(n-3)]. In a strictly controlled experiment, we fed 18 men two mixed natural diets for four weeks, in random order. LNA content during the walnut diet (2.8% of total calories) was nearly triple the control diet (1.0% of total calories). LNA and EPA increased by 119% and 23%, respectively. DHA decreased by 30% from control to walnut, possibly due to competition for elongase and desaturase enzymes by elevated linoleic acid [18:3(n-6)] levels in walnuts. The product precursor ratio 20:5(n-3)/18:3(n-3) decreased from 0.79 in the control to 0.44 in the walnut diet (p<0.005). Subsequent 22:6(n-3)/18:3(n-3) ratio dropped further from control, 1.59, to walnut, 0.51, (p<0.005). The decrease in (EPA+DHA)/LNA ratio from 2.08 in control to 0.90 in walnut (p<0.005) was consistent with the product precursor ratios. Thus, diets rich in -3 fatty acids from plant sources greatly increase LNA in serum cholesterol esters but only moderately EPA. Ratios of these -3 fatty acids suggest limitations in tissue metabolism possibly due to rate-limiting precursor levels, or competitive inhibition by -6 fatty acids.
INFLUENCE OF INTAKE FREQUENCY OF FRUIT AND VEGETABLES ON ENDOTHELIAL FUNCTION IN MIDDLE-AGED MEN. R. Pullmann, I. Bukovsky, P. Hra ko, Department of Clinical Biochemistry, Faculty Hospital, Martin and Institute of Physiology, Comenius University, Bratislava, Slovak Republic.
On the basis of experimental as well as clinical observations, is endothelial dysfunction - EDf (defined as impaired or absent endothelium-dependent relaxation) considered to be very important point in the process of atherogenesis. As we have already shown, EDf in middle-aged men is correlated with certain indicators of lipoperoxidation (e.g. MDA, SOD) in vivo.
We have further analyzed the influence of dietary habits on endothelial function and the level of oxidation in sixty men 25 to 45 years old. We have found positive correlation between endothelial function expressed as functional vasodilation reserve and fresh fruit consumption (P = 0.0190), while vegetable consumption and endothelial function show a positive correlation (P=0.0023).We also found a strong correlation between SOD and fresh fruit consumption (p<0.05), suggesting the SOD-saving effect of phytochemical complex of fresh fruits. Consumption of dark green leafy vegetables 3 - 7-times per week was connected with significantly (P = 0.0088) higher HDL (mean HDL = 1.6500) than the consumption 2-times and less per week (mean HDL = 1.2153). Negative correlation (p = 0.0398) between dark green leafy vegetables and TCH/HDL ratio (mean TCH/HDL = 3.2194 in men with high frequency of use, versus mean TCH/HDL = 5,1136 in men with low frequency of use) also underlines the positive effect of vegetables on lipid parameters.
Analysis suggests that we can assume a significant influence of diet on lipid oxidation and/or the endothelial function, and due to this, employ a change toward substantially increased consumption of fruits and vegetables.
ANIMAL PRODUCT INTAKE AND IMMUNE FUNCTION. David C. Nieman, Diane E. Butterworth, Sandra L. Nehlsen-Cannarella, Omar R. Fagoaga. Dept. Health & Exercise Science, Appalachian State University, Boone, NC; Immunology Center, Loma Linda University Medical Center, Loma Linda, CA.
The purpose of this research project was to study the relationship of animal product intake and immune function in women while controlling for potential confounding factors. Animal product and nutrient intake was measured in 80 healthy women who differed widely in age (45.6±1.1 years, range 27-72), body mass (80.8±2.2 kg, range 52-156), dietary intake, and maximal aerobic power (26.7±1.1 ml kg-' min-', range 12.7-50.7), and related to immune function measures. Multiple regression models were used to control for factors known to influence immune function including age, aerobic fitness, body composition, and psychological well-being. Immune measures included most major leukocyte subsets (natural killer cell activity, granulocyte/monocyte phagocytosis and oxidative burst activity, mitogen-induced T and B lymphocyte proliferation). Various food indexes and nutrient ratios from three-day food records were included in the calculations, including a fruit-vegetable index (total of fruit and vegetable food exchanges), a meat-milk index (total of meat and milk exchanges), the vitamin B-12 nutrient density (vitamin B-12/1000 kilocalories), and the cholesterol nutrient density (cholesterol/1000 kilocalories). Animal product and nutrient intake were unrelated to immune function when controlling for potential confounding factors, except for a negative correlation between zinc and natural killer cell activity (r=-0.36, P=0.006). These data do not support the contention that animal product intake is associated with alterations in immune function. Supported by the Cybex Grant from the American College of Sports Medicine
VEGETARIAN RAW FOOD DIETARY: HEALTH HABITS AND NUTRIENT INTAKE. Carola B. Strassner, Sabine Doerries, Karunee Kwanbunian, Claus Leitzmann, Institute of Nutritional Science, Justus-Liebig-University Giessen, Germany
The Raw Food Diet (RFD) is one of a number of alternative dietary regimens currently enjoying popularity. Though known under the above name, the movement consists of a wide variety of different RFD, most of which are vegetarian regimens. Common to all is the high proportion of raw food in the diet: extreme forms consist of a nutrition comprised solely of raw foods. The Giessen Raw Food Study aimed to examine the various RED forms in (Germany and to determine the health behavior and nutritive status of raw food eaters. Health habits were investigated by means of a detailed questionnaire. Data from this nationwide survey indicate that a quarter to a third of the participants are underweight according to their BMI. Extreme RFD are more often practiced by younger participants and by males. Most are highly content with their diet and almost 98% intend to follow their RFD as a long-term regimen. About half the participants gave an own disease as the reason for changing to a RFD. Women who adhere to the stricter forms stated that their menstruation became infrequent or stopped altogether. Food consumption and nutrient intake were calculated from a 7-day estimated food record. For most participants the consumption of raw food lay above 90%. The diet consists primarily of fruit and vegetables. The intake of nutrients that are usually provided by foods of animal origin is insufficient. These include Vitamin B 12 and D, zinc and calcium. On the other hand, the intake of certain protective nutrients, such as Vitamin C and other antioxidants, lie above the national average. The authors are grateful to the Atoll Foundation, Germany, for research funding.
BIOMARKERS OF CHEMOPREVENTION IN LONG-TERM ADHERENTS TO A STRICT UNCOOKED VEGAN DIET ("LIVING FOOD" DIET). Anna-Liisa Rauma, Hans Verhagen 2, Riitta Törrönen 1, Hannu Mykkänen 1, 1 Departments of Clinical Nutrition and Physiology, University of Kuopio, Finland, 2 TNO Nutrition and Food Research Institute, AT, Zeist, The Netherlands.
In order to study the potential beneficial effects of a vegan diet on biomarkers of chemoprevention, a cross-sectional study was performed and several biomarkers of chemoprevention were measured in a population of female "living food" eaters (vegans, n=20) vs. matched omnivorous controls (n=20). White blood cells obtained from fresh blood samples were subjected to the single-cell gel-electrophoresis assay and the number of binucleated lymphocytes with micronuclei were calculated before and after treating the fresh cells with mitomycin C. The content of glutathione S-transferase in plasma was measured using RIA. There were no statistically significant differences between the vegans and controls in any of the parameters studied. However, the "tail moment" was significantly lower in a subset of the vegans (i.e., in those who did not use any health supplements), and a significant negative correlation (r=0.64, p<0.01) between the number of mitomycin C-induced micronuclei and the activity of erythrocyte superoxide dismutase was found in the vegans. The present data indicate only minor differences in biomarkers of chemopreventive potential in strict vegans vs. matched omnivorous controls. This finding may be due that the "living food" diet has both beneficial (high supply of antioxidants) and harmful substances (a low supply of vitamin B-12) characteristics as regards the chemopreventive potential.
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