Poster presentations
Section I: Diet and Chronic Disease
THE EFFECT OF NUTRITIONAL
AND CLINICAL FACTORS UPON SERUM PROSTATE SPECIFIC ANTIGEN AND PROSTATE
CANCER IN A POPULATION OF ELDERLY CALIFORNIA MEN. D.
Baldwin, G. Naco, F. Petersen, G. Fraser, H. Ruckle. Loma Linda University,
Loma Linda, CA,USA.
Dietary factors have been associated with a risk for prostate cancer including fat, vitamins, isoflavonoids and lycopenes. In an attempt to determine whether increases in Prostate Specific Antigen (PSA) might precede later diagnosis of cancer, we studied the influence of diet upon PSA and prostate cancer.
Method: We undertook a study of 60-80 year old Seventh-day Adventist men who had completed a detailed diet and lifestyle questionnaire in 1976. Twenty years later in 1995, a total of 940 men completed a second detailed dietary and lifestyle questionnaire and had serum PSA determined.
Results: Factors associated with abnormal PSA (PSA>4) included age (p<.001, OR=1.1), self-reported "prostate enlargement" (p<.001, 0R= 2.5), and previous transurethral resection of the prostate (p=.03, OR=.41). Prostate cancer (n=81) was found to be associated with age (p<.001, OR=1.1), prior prostate infection (p<.001, OR=3.6), brother with prostate cancer (p<.001, OR=4.4) and "prostate enlargement" (p<.001, OR=3.7). In a cross-sectional analysis of the 1995 questionnaire, dietary food groupings analyzed including tomatoes, vegetables, legumes, fish, meat, and soy were not associated with PSA or prostate cancer. However, consumption of wheat based glutens were inversely associated with PSA (p=.02, OR=.10). Food groupings analyzed longitudinally using the 1976 and 1995 questionnaires suggested consistent high consumption of tomatoes is protective for both "prostate enlargement" (p=.02, OR=.63) and a PSA>4 and/or prostate cancer (p=.03, OR=.59) when compared with low consumption.
Conclusion: This study reveals
those with a history of prior prostate infections and enlargement may
be more likely to develop prostate cancer. An inverse association between
consumption of tomatoes and PSA >4 and/or prostate cancer and "prostate
enlargement" was also suggested by our study.
DIETARY PHYTOCHEMICALS MODULATE
THE MUTAGENIC ACTIVATION OF HETEROCYCLIC AMINES.
Solomon M. Hamilton,
Department of Biology, La Sierra University, Riverside, CA, Zhno Zhang
and Robert W. Teel, Department of Physiology and Pharmacology, Loma
Linda, CA, USA.
Plants synthesize and contain
compounds with antimutagenic and anticarcinogenic properties. In this
study, we investigated the effects of benzyl isothiocyanate (BITC) and
phenethyl isothiocyanate (PEITC) that occur naturally in cruciferous
vegetables and capsaicin, the principal component of Capsicum
fruits, on the mutagenic
activation of five heterocyclic amines in the Salmonella
- rnicrosome mutagenicity
assay (Ame's test). Heterocyclic amines form during the cook~ng of foods
by the pyrolys~s of amino acids and proteins. They have been shown to
be carcinogenic in a number of animal models. Heterocyclic amines are
mutagenically activated by microsomal enzymes known as cytochrome P450s
(CYP450), specifically CYP4501A1 and CYP4501A2. Capsaicin, BITC and
PEITC strongly inhibited the mutagenicity of the heterocyclic amines
tested as determined by the number of histidine-positive revertant colonies
in Salmonella typhimurium strain
TA98. The inhibition of mutagenic activity of the heterocyclic amines
correlated with the inhibition of deethylation of ethoxyresorufin and
demethylation of methoxyresorufin that measure CYP4501A1 and CYP4501A2
activity, respectively. Our data suggest that capsaicin, BITC and PEITC
possess chemopreventive properties that may be anumutagen~c and anticarcinogenic.
EFFECTS OF A VEGETARIAN DIET
ON SOME PROPOSED RISK FACTORS FOR CANCER Gunnar K. Johansson. Department of Food and Nutrition, University of Umea,
Sweden.
A Multitude of epidemiological
studies have demonstrated a relationship between diet and cancer. However,
the mechanisms behind these connections are unclear. This is a compilation
of six articles on the effect of a shift from a well balance mixed diet
to a facto-vegetarian diet on some cancer associated variables. Twenty
normal weight, non-smoking, healthy omnivores (mean age 44 years) who
were on no medical treatment changed from a mixed diet to a facto-vegetarian
diet. A dietary survey was performed and fecal and urinary samples collected
before and three months after the shift to a facto-vegetarian diet.
The shift resulted in no change in carbohydrate and fiber intake. The
excretion of short chain fatty acids and fecal weight increased significantly.
There were decreases in the total fecal concentrations of soluble fatty
acids, deoxycholic acid, beta-glucuronidase, beta-glucosidase, sulphatase
and mutagenic activity and also a decrease in urinary mutagenic activity.
Part of the explanation for the decreased fecal characteristics is obviously
a dilution effect, because much of the increased fecal weight after
the shift in diet was associated with a higher water content. To conclude,
these studies indicate that it is possible to detect a decrease in proposed
risk variables for cancer upon changing from a well balanced mixed diet
to a so-called low risk diet for colon cancer.
ROLE OF VEGETARIAN DIET IN
CANCERS OF OESOPHAGUS AND FEMALE BREAST IN INDIA. D.N. Rao, Division of Epidemiology and Biostatistics, Tata Memorial
Hospital Parel, Mumbai - 400 012, India.
In India by religious custom, a large section of the Hindu population practice vegetarian diet and totally avoid poultry products, animal fats and fish in their diet. In order to assess the effect of non-vegetarian diet in cancers of oesophagus and female breast a separate case control study was conducted.
A case control study of 503 oesophageal cancer cases in males and 634 controls registered at the Tata Memorial Hospital during the period 1980-84 was carried out to determine the association of oesophageal cancer with two types of dietary practices, viz., vegetarian and non-vegetarian, in addition to tobacco and alcohol habits. In the presence of an alcohol habit, the relative risk for tobacco chewing and smoking was observed to be high in the non-vegetarian group compared to the vegetarian group. A vegetarian diet was found to be protective in our study.
A case-control study of 689
breast cancer patients and 711 females (controls) did not show non-vegetarian
diet as a significant risk factor.
DIETARY RISK FACTORS FOR
COLON CANCER IN A LOW RISK POPULATION: FINDINGS FROM THE ADVENTIST HEALTH
STUDY. Pramil N. Singh, Gary E. Fraser. Center for Health Research, Loma Linda
University, Loma Linda, CA, USA.
In a six-year prospective cohort
study, we examined the relation between diet and incident colon cancer
among 32,051 non-Hispanic, white cohort members of the Adventist Health
Study. This population was characterized by a low prevalence (< 4%)
of current smoking or alcohol use, and thirty percent ate no meat. The
risk of colon cancer for intake levels of specific foods was determined
from proportional hazard regression. In the total population, a positive
association with meat intake (RR [95% Cl]
for non-vegetarian
versus strict
vegetarian, 1.84 [1.20,
2.81); trend, p =
0.01) and a negative association with legume intake (RR [95% CI)
for > 2 x / week
versus <
1 x / week, 0.52 [0.
32, 0.85], trend,
p = 0.02) was observed. Among subjects favoring specific types of meat,
significant positive associations for red meat and white meat (fish
+ poultry) were also observed. An effect due to the relative intake
of meat and legumes was shown whereby the increase in risk due to meat
intake was most evident among those in the low intake category of legumes
(RR [95% CI] for non-vegetarian versus strict vegetarian, 2.58 [1.21, 5.501; trend, p = 0.009) and the decrease in risk due to legume
intake was most evident among those in the high intake category of meat
(RR [95% CI] for > 2 x / week versus < 1 x / week 0 34
[0.14, 0.867, trend,
p = 0.004). The findings from this population identify both red and
white meat intake as important dietary risk factors for colon cancer,
and raise the possibility that the risk due to meat intake can be modified
by consumption of legumes.
SYNDROME-AC: NIDDM AND THE
ANABOLIC/CATABOLIC PARADOX. Steve Provonsha, Kaiser Permenante, Riverside, CA, USA.
A review of medical literature
suggests a mechanism for development of NIDDM. While many possible mechanisms
and numerous loci of Insulin resistance have been studied, there emerges
one underlying theme; the abnormal activation of catabolic body chemistry
during the anabolic process of eating. Patients with NIDDM have elevated
blood levels of glucagon, cortisone, fatty acids protein and glucose
as well as other components of catabolism. The activatlon of catabolic
pathways in the body is a powerful force which results in a multilevel,
multi-site interference with glucose handling. It is proposed that NIDDM
is a chronic result of the dietary activation of catabolic chemistry
simultaneously with that of anabolic chemistry. Since muscle protein
and saturated fat are the blood messengers of catabolism ordinarily
set free when insulin levels fall, it appears the dietary consumption
of muscle and fat is creating a system-wide pseudo-catabolism interfering
with the carbohydrate portion of a meal. In addition, ingestion of injured
muscle tissue may be releasing other tissue catabolism cues such as
tumor necrosis factor (TNF) ordinarily set free when the body is injured.
This and similar substances cause profound insulin resistance. In spite
of this, overt hyperglycemia is masked for decades by elevated insulin
levels which appear to act on peripheral body fat stores causing weight
gain until on upper limit of insulin production is reached. The failure
of the anabolic compensation of Insulin results in clinical diabetes.
In a series of 89 patients on a muscle free diet, averagee blood sugars
were reduced by 78.3 mg/dl (p=3x10-15), blood insulin levels were reduced 30.6% or 8.1 micro
IU/ml (p=6.6xlO-4), triglycerides by 61.4 mg/dl (p=0.047) and a weight
loss average of 3.6 Ibs per month over an average of 114 days.
THE EFFECT OF A LOW-FAT, UNREFINED,
VEGAN DIET ON NIDDM. A.S. Nicholson. M.D., Physicians Committee for Responsible Medicine, Washington,
D.C., U.S.A.
This study is a prospective, randomized, controlled trial to determine whether a low-fat, unrefined, vegan diet is more effective than a commonly recommended diabetic diet at controlling non-insulindependent diabetes (NIDDM) and improving risk factors associated with macrovascular complications. Persons with NIDDM were screened at the Georgetown University Medical Center, and 13 were randomly assigned to the experimental or control diet group for an intensive, three-month intervention in a community setting.
Significant diet group differences
were found for weight and fasting blood glucose (FBG), although the
subject sample size was intentionally small in accordance with the study
design. The vegan group lost an average of 15.6 pounds over 12 weeks,
while the control group lost an average of 8.4 pounds. The experimental
group mean FBG decreased by 28% to 140.9 mg/dl. The control group mean
FBG decreased by 12% to 157 mg/dl. Diabetic medications were decreased
in the vegan group, while no subject in the control group achieved serologic
changes requiring medication adjustment. Substantial group differences
were found for total serum cholesterol and 24-hour microalbuminuria.
An unrefined, exclusively plant-based diet may be substantially more
effective than the standard diabetic diet at controlling NIDDM and improving
risk factors for macrovascular disease. Subjects with NIDDM are able
to adhere well to the plant-based diet with research supports in a community
setting. The clinical differences between the two diet groups are sufficiently
great to reach statistical significance even with a small sample size.
RAPID REDUCTION OF SERUM
CHOLESTEROL AND BLOOD PRESSURE BY A TWELVE-DAY, VERY LOW FAT, STRICTLY
VEGETARIAN DIET. John McDougall, Vicki Saunders and Gene A. Spiller, St. Helena Hospital,
Deer Park, CA and the Sphera Foundation, Los Altos, CA, USA.
Objective: This study was conducted to demonstrate the effectiveness of a strictly vegetarian, very low-fat diet on cardiac risk factor modification.
Methods: Five hundred men and women, participants in an intensive 12-day live-in program, were studied. The program focused on dietary modification, moderate exercise, and stress management at a hospital-based health-center.
Results: During this short time period, cardiac risk factors improved: there was an average reduction of total serum cholesterol of 11% (p<0.001), of blood pressure of 6% (p<0.001), and a weight loss of 2.5kg for men and 1 kg for women. Serum triglycerides did not increase except for two subgroups females age >65 years with serum cholesterol <6.5 mmol/L and for females 50 to 64 years with baseline serum cholesterol between 5.2-6.5 mmol/L. High density lipoprotein cholesterol measured on 66 subjects decreased by 19%.
Conclusion: A strict, very
low-fat vegetarian diet free from all animal products combined with
lifestyle changes that include exercise and weight loss is an effective
way to lower serum cholesterol and blood pressure.
EFFECTS OF DIET AND EXERCISE
ON INTRAOCULAR PRESSURE AND CARDIAC RISK FACTORS.
S. G. Mellgren,
M. G. Crane, R. Gregory, W. Zinke. Weimar Institute, Weimar, CA, USA.
To evaluate the short-term
effects of diet and exercise on intraocular pressure (IOP), we compared
the IOP of 91 patients who had changes in diet and exercise to 30 age,
sex and smoking matched controls. The intervention consisted of a low-fat
(10-25% cal from fat), high fiber, no cholesterol, total vegetarian
diet with exclusion of refined foods; and exercise in the form of brisk
walking, a minimum of thirty minutes or two miles per day. Goldmann
applanation tonometry was performed at the same time of day. After 14
days, patients in the study group demonstrated a mean decrease of 11.3%
and 10.0% in intraocular pressure of the right and left eye, respectively,
while the control group demonstrated no significant change. We also
measured a mean decrease of 16.4% in plasma lipoprotein (a), 12.1% in
plasma cholesterol, 16.5% in low density lipoprotein, 3.3% in high density
lipoprotein, 8% in triglycerides, 7.7% in systolic blood pressure, 10.6%
in fasting blood glucose, and 2.2% in weight. These systemic changes
show an improvement in cardiac risk factors, some of which apply to
IOP and glaucomatous optic neuropathy (GON). IOP, the primary risk factor
in GON, is positively correlated with blood pressure and obesity. Other
risk factors for GON include systolic hypertension, diabetes, and peripheral
vascular disease. These short-term improvements in IOP seem to result
from changes in diet and exercise which may be adjuvants to conventional
treatment of glaucomatous optic neuropathy (GON).
SELENIUM DEFICIENCY AND
INCREASED CORONARY MORTALITY IN SOUTH INDIAN VEGETARIANS.
K.Radha Shanmugasundaram,
Department of Biochemistry, PG Institute of Basic Medical P Sciences,
University of Madras, Madras India.
Urban South Indians have several-fold higher coronary mortality than North Indians. The South Indian diet is sparing in saturated fat and fat derived calories (<20%), animal proteins and rich in fibre. The dietary aberrations causing coronary mortality is yet to be identified. Epidemiological studies have shown an inverse relationship between blood selenium levels and coronary heart disease (CHD). Selenium is a constituent of Glutathione Peroxidase, an enzyme which inactivates the toxic hydrogen peroxide and hydroperoxides. Selenium is identified as an essential antioxidant nutrient.
Selenium status was studied in South Indian Vegetarians by a) dietary survey of 880 urban South Indian adults, b) analysis of selenium content in food constituents, and c) assay of plasma and RBC selenium in adults with and without CHD.
In the lacto vegetarian diet, the legumes namely red gram and black gram and wheat, parboiled rice and milk provide selenium. Finger millet rich in selenium is consumed very sparingly. In lactovegetarians, dietary selenium ranged from 15 to 42 (mean 25) and 11 to 32 (mean 20) ,ug per day for males and females respectively. The omnivores consumed 18 to 115 (mean 46) and 15 to 89 (mean 35) ,ug selenium per day. USRDA for males and females are 70 and 55 ,ug selenium per day. Selenium intake in urban South Indian in low, especially among the vegetarians and could contribute to the development of CHD.
Red cell selenium levels are in the lower range 90-140 ng/g, compared to 75-240ng/g reported in USA. In CHD, red cell selenium is lowered and is in the range of 27 to 131/ng/g.
Selenium in South Indian vegetarian diet can be enhanced by substituting polished rice with parboiled rice, wheat and finger millet, as in the North Indian diet.
DIETARY VITAMIN E AND RISK
OF CORONARY HEART DISEASE IN CALIFORNIA SEVENTH-DAY ADVENTISTS.
Peter Pribs
, Gary Fraser, Georgia Hodgkin, Joan Sabaté, Center for Health
Research, Adventist Health Studies, School of Public Health, Loma Linda
University, Loma Linda, CA, USA.
There is growing evidence that dietary antioxidant vitamins can prevent oxidative modification of low-density lipoproteins, thereby inhibiting the promotion of atherosclerosis. We studied 14,181 (8,319 women and 5,862 men) California Seventh-day Adventists aged 25-70 years with no Coronary Heart Disease (CHD) who in 1976 completed a Food Frequency Questionnaire (FFQ) that assessed, among other factors, their intake of vitamin E from food sources. The validity correlation comparing the vitamin E intake calculated from the FFQ was five 24-hour dietary recalls was 0.30. During the six years of follow-up, 46 men and 8 women experienced a non-fatal CHD. When fatal CHD is the endpoint, data are available for twelve years of follow-up, during which 59 men and 29 women died of CHD incident. In Proportional Hazard regression analyses adjusted for age, gender and envergy intake, dietary vitamin E appeard to be inversely associated with the risk from fatal CHD (relative risks from lowest to highest tertile for men, 1.0, 0.36, 0.78, P for trend=0.13 for women, 1.0, 0.42, 0.74, P for trend=0.57, and when both sexes are combined 1.0, 0.37, 0.70, P for trend=0.08). For non-fatal CHD, relative risks from lowest to highest tertile of vitamin E in men are, 1.0, 0.49, 0.10, P for trend=0.003, and when both sexes are combined, 1.0, 0.50, 0.22, P for trend=0.003. These results indicate that intake of vitamin E from foods alone protects against non-fatal CHD, and supports previous observations from other epidemiological studies regarding fatal CHD.
[Vegetarian Congress contents]
All contents copyright © 2001 Loma
Linda University. All rights reserved.
Revised
Monday, January 15, 2001 10:40 AM
Send comments and questions to webmaster@univ.llu.edu
URL: http://www.llu.edu