spacer
Life Extension
 

Life Extension is a global authority on nutrition, health and wellness

as well as a provider of scientific information on anti-aging supplements and therapies. We supply only the highest quality nutritional supplements, including minerals, vitamins, herbs and hormones.

Access your account today: Login        Learn about our membership benefits

translation by SYSTRAN  
Life Extension Overstock Sale - Save 60% to 75% - SHOP NOW
 
Life Extension Magazine




May 9, 2000

 

National Academy of Sciences References


461. JAMA 1994 Nov 9;272(18):1413-20
Published erratum appears in JAMA 1995 Feb 22;273(8):622
Dietary carotenoids, vitamins A, C, and E, and advanced age-related macular
degeneration. Eye Disease Case-Control Study Group.
Seddon JM, Ajani UA, Sperduto RD, Hiller R, Blair N, Burton TC, Farber MD,
Gragoudas ES, Haller J, Miller DT, et al
Epidemiology Unit, Massachusetts Eye and Ear Infirmary, Boston 02114.

OBJECTIVE--To evaluate the relationships between dietary intake of carotenoids and vitamins A, C, and E and the risk of neovascular age-related macular degeneration (AMD), the leading cause of irreversible blindness among adults. DESIGN--The multicenter Eye Disease Case-Control Study. SETTING-Five ophthalmology centers in the United States. PATIENTS--A total of 356 case subjects who were diagnosed with the advanced stage of AMD within 1 year prior to their enrollment, aged 55 to 80 years, and residing near a participating clinical center. The 520 control subjects were from the same geographic areas as case subjects, had other ocular diseases, and were frequency-matched to cases according to age and sex. MAIN OUTCOME MEASURES--The relative risk for AMD was estimated according to dietary indicators of antioxidant status, controlling for smoking and other risk factors, by using multiple logistic-regression analyses. RESULTS--A higher dietary intake of carotenoids was associated with a lower risk for AMD. Adjusting for other risk factors for AMD, we found that those in the highest quintile of carotenoid intake had a 43% lower risk for AMD compared with those in the lowest quintile (odds ratio, 0.57; 95% confidence interval, 0.35 to 0.92; P for trend = .02). Among the specific carotenoids, lutein and zeaxanthin, which are primarily obtained from dark green, leafy vegetables, were most strongly associated with a reduced risk for AMD (P for trend = .001). Several food items rich in carotenoids were inversely associated with AMD. In particular, a higher frequency of intake of spinach or collard greens was associated with a substantially lower risk for AMD (P for trend < .001). The intake of preformed vitamin A (retinol) was not appreciably related to AMD. Neither vitamin E nor total vitamin C consumption was associated with a statistically significant reduced risk for AMD, although a possibly lower risk for AMD was suggested among those with higher intake of vitamin C, particularly from foods. CONCLUSION--Increasing the consumption of foods rich in certain carotenoids, in particular dark green, leafy vegetables, may decrease the risk of developing advanced or exudative AMD, the most visually disabling form of macular degeneration among older people. These findings support the need for further studies of this relationship.

462. Cancer Epidemiol Biomarkers Prev 1994 Oct-Nov;3(7):571-4
Increased plasma level of cholesterol-5 beta,6 beta-epoxide in endometrial
cancer patients.
Kucuk O, Churley M, Goodman MT, Franke A, Custer L, Wilkens LR, St Pyrek J
Prevention and Control [O. K., M. C.], Epidemiology [M. T. G., L. R. W.], and
Molecular Oncology [A. F., L. C.], University of Hawaii, Honolulu 96813.

Plasma levels of alpha- and beta-isomers of cholesterol-5, 6-epoxides were
quantitated in a pilot study of 9 women with endometrial cancer and 9 race- and
age-matched control women by isotope dilution gas chromatography/mass
spectrometry. Endometrial cancer cases had significantly higher cholesterol-5
beta,6 beta-epoxide levels than the controls (P = 0.01). The mean plasma
beta-epoxide level was 0.71 0.46 ng/ml for the cases and 0.35 0.25 ng/ml
for the controls. No significant differences were found between the plasma
alpha-epoxide levels of the cases and the controls. Plasma levels of various
carotenoids, tocopherols, and ascorbic acid were also quantitated by high
performance liquid chromatography. An inverse correlation was present between the plasma levels of cholesterol-5 beta,6 beta-epoxide and cis-lutein/zeaxanthin
(P = 0.01). These data suggest a possible role for cholesterol-5 beta,6
beta-epoxide as a biomarker of endometrial cancer risk. Further studies are
warranted to investigate the possible association between the oxidation products of cholesterol and endometrial cancer and to determine the interactive role of antioxidants.

463. Circulation 1994 Sep;90(3):1154-61
Serum antioxidants and myocardial infarction. Are low levels of carotenoids and
alpha-tocopherol risk factors for myocardial infarction?
Street DA, Comstock GW, Salkeld RM, Schuep W, Klag MJ
Department of Epidemiology, Johns Hopkins University School of Hygiene and
Public Health, Baltimore, Md.

BACKGROUND: In vitro, animal and epidemiological studies suggest that
lipoprotein oxidation may play an important role in atherosclerosis.
Antioxidants may protect against lipoprotein oxidation and in that way inhibit
atherosclerosis and its clinical sequelae. To investigate this possibility, we
examined the association between levels of several antioxidants and myocardial
infarction using serum specimens collected 7 to 14 years before the onset of
myocardial infarction. METHODS AND RESULTS: A nested case-control design was used. Cases and control subjects were selected from the 25,802 persons who had donated 15 mL of blood in 1974 for a serum bank. Cases comprised 123 persons with a subsequent first diagnosis of myocardial infarction who ranged from 23 through 58 years of age in 1974 and who had had their first diagnosis of myocardial infarction during 1981 to 1988. Two groups of control subjects matched to the cases for sex and age were selected from donors to the serum bank, one from those with hospital admissions during the same period and the other from the total group of donors. Sera were assayed for four carotenoids (beta-carotene, lycopene, lutein, and zeaxanthin), alpha-tocopherol, and cholesterol. Because associations with these serum nutrients showed similar trends whether based on hospital or community controls, the two control groups were combined. There was a significantly increasing risk for subsequent
myocardial infarction with decreasing levels of beta-carotene in 1974 (P value
for trend, .02) and a suggestive trend with decreasing levels of lutein (P =
.09). When the results were stratified by smoking status, the excess risk of
myocardial infarction associated with low serum levels of carotenoids was
limited to smokers. A protective association with higher levels of
alpha-tocopherol was suggested only among persons with high levels of serum
cholesterol. CONCLUSIONS: Low serum levels of carotenoids were associated with an increased risk of subsequent myocardial infarction among smokers.

464. Am J Clin Nutr 1994 Apr;59(4):891-5
Effect of smoking on serum nutrient concentrations in African-American women.
Pamuk ER, Byers T, Coates RJ, Vann JW, Sowell AL, Gunter EW, Glass D
Division of Nutrition, Centers for Disease Control and Prevention, Atlanta.

The relationship between current cigarette smoking and serum concentrations of
vitamins C, E, and A, and of five carotenoids in human serum were examined in 91

low-income, African-American women. General linear models were used to adjust geometric mean serum concentrations of micronutrients for age, dietary and supplement intakes, total energy intake, alcohol intake, medication use, body mass index, and serum concentrations of cholesterol and triglycerides. Among smokers, serum concentrations of alpha-carotene, beta-carotene, cryptoxanthin, and lycopene averaged only 71-79% of the concentrations among nonsmokers. Mean serum concentrations of vitamins C and E and lutein/zeaxanthin were only slightly lower among smokers relative to nonsmokers, and current smokers had higher serum concentrations of vitamin A. Among current smokers, mean serum concentrations of all five carotenoids decreased with an increase in the amount smoked. The negative effect of smoking on serum concentrations of antioxidant carotenoids may pose a serious health risk in low-income populations already at higher risk for many chronic diseases.

465. Cancer Epidemiol Biomarkers Prev 1993 Jul-Aug;2(4):335-9
Serum micronutrients and the subsequent risk of cervical cancer in a
population-based nested case-control study.
Batieha AM, Armenian HK, Norkus EP, Morris JS, Spate VE, Comstock GW
Department of Epidemiology, School of Hygiene and Public Health, Johns Hopkins University, Baltimore, Maryland 21205.

A nested case-control study was conducted in Washington County, MD, to determine whether low serum micronutrients are related to the subsequent risk of cervical cancer. Among the 15,161 women who donated blood for future cancer research during a serum collection campaign in 1974, 18 developed invasive cervical cancer and 32 developed carcinoma in situ during the period January 1975 through May 1990. For each of these 50 cases, two matched controls were selected from the same cohort. The frozen sera of the cases and their matched controls were analyzed for a number of nutrients. The mean serum levels of total carotenoids, alpha-carotene, beta-carotene, cryptoxanthin, and lycopene were lower among cases than they were among controls. When examined by tertiles, the risk of cervical cancer was significantly higher among women in the lower tertiles of total carotenoids (odds ratio 2.7; 95% confidence limit, 1.1-6.4), alpha-carotene (odds ratio, 3.1; 95% confidence limit, 1.3-7.6), and beta-carotene (odds ratio, 3.1; 95% confidence limit, 1.2-8.1) as compared to women in the upper tertiles and the trends were statistically significant.
Cryptoxanthin was significantly associated with a lower risk of cervical cancer
when examined as a continuous variable. Retinol, lutein, alpha- and
gamma-tocopherol, and selenium were not related to cervical cancer risk. Smoking was also strongly associated with cervical cancer. These findings are suggestive of a protective role for total carotenoids, alpha-carotene and beta-carotene in cervical carcinogenesis and possibly for cryptoxanthin and lycopene as well.

466. Cancer Epidemiol Biomarkers Prev 1993 May-Jun;2(3):183-7
Published erratum appears in Cancer Epidemiol Biomarkers Prev 1994 Sep;3(6):523 Intake of specific carotenoids and lung cancer risk.
Le Marchand L, Hankin JH, Kolonel LN, Beecher GR, Wilkens LR, Zhao LP
Cancer Research Center, University of Hawaii, Honolulu 96813.

Using newly available food composition data for carotenoids, the authors
reanalyzed a population-based case-control study of diet and lung cancer
conducted in Hawaii in 1983-1985 (L. Le Marchand et al., J. Natl. Cancer Inst.,
81158-1164, 1989). The analysis included interviews with 230 men and 102
women with lung cancer and 597 men and 268 women as controls, frequency-matched to the patients by age and sex. A previously validated quantitative diet history assessed the usual intake of foods rich in carotenoids. After adjusting for
smoking and other covariates, no association was found with lung cancer risk for dietary lycopene or beta-cryptoxanthin intake, whereas dose-dependent inverse associations of comparable magnitude were found for dietary beta-carotene, alpha-carotene, and lutein. When subjects were cross-classified by their joint intakes of the latter three carotenoids, those who had a high intake (> median) for all three had the lowest risk for lung cancer. In a similar two-way
interaction analysis, the previously reported inverse association of lung cancer
with vegetable consumption in these data was found to be stronger than that with intake of these three carotenoids. Consistent with our previous findings, this
analysis provides further evidence for a protective effect of certain carotenoids against lung cancer and for the greater protection afforded by consuming a variety of vegetables compared to only foods rich in a particular
carotenoid.

467. Cancer Res 1993 Feb 1;53(3):536-43
Vegetables, fruit, and lung cancer in the Iowa Women's Health Study.
Steinmetz KA, Potter JD, Folsom AR
Division of Epidemiology, School of Public Health, University of Minnesota,
Minneapolis 55454-1015.

Previous epidemiological studies have shown an inverse association between
vegetable and fruit consumption and lung cancer risk; few of these studies have
been prospective or have focused upon women. In 1986, we assessed food intake in 41,837 Iowa women, aged 55 to 69 yr, with a mailed 127-item food frequency questionnaire. After 4 years of follow-up, 179 incident cases of lung cancer were identified via the Iowa Surveillance, Epidemiology, and End Results cancer registry. After specific exclusion criteria were applied, a nested case-control comparison of 138 cases with 2,814 randomly selected noncases was undertaken. Intakes, in the upper-most quartile, of 11 vegetable and fruit groups, as well as of the nutrients beta-carotene and vitamin C, were explored. High intakes of all vegetables and fruit, all vegetables, and green leafy vegetables were each associated with an approximate halving of risk: age-, smoking-, and
energy-adjusted odds ratios (ORs) were 0.49 (95% confidence interval,
0.28-0.86), 0.50 (95% confidence interval, 0.29-0.87), and 0.45 (95% confidence
interval, 0.26-0.76), respectively. A lower lung cancer risk was also seen for
all fruit (adjusted OR = 0.75 for high consumption), high vitamin C vegetables
and fruit (OR = 0.75), carrots (OR = 0.71), and brocolli (OR = 0.72) and for the
nutrients beta-carotene (OR = 0.81) and vitamin C (OR = 0.81) (all 95%
confidence intervals included 1.0). Lung cancer risk was unrelated to
consumption of the three food groups defined as "high-carotenoid"
(beta-carotene, lutein, and lycopene) and tomatoes. In an analysis stratified by
histological type of lung cancer, the strongest inverse associations for
vegetables and fruit were seen for large cell carcinoma. Analysis by smoking
status showed the inverse associations for most vegetable and fruit groups with
lung cancer risk to be stronger for exsmokers than for current smokers. Results
from the stratified analyses must be interpreted with caution because of the
small number of cases in each stratum.

468. Cancer Res 1993 Feb 1;53(3):536-43
Vegetables, fruit, and lung cancer in the Iowa Women's Health Study.
Steinmetz KA, Potter JD, Folsom AR
Division of Epidemiology, School of Public Health, University of Minnesota,
Minneapolis 55454-1015.

Previous epidemiological studies have shown an inverse association between
vegetable and fruit consumption and lung cancer risk; few of these studies have
been prospective or have focused upon women. In 1986, we assessed food intake in 41,837 Iowa women, aged 55 to 69 yr, with a mailed 127-item food frequency questionnaire. After 4 years of follow-up, 179 incident cases of lung cancer were identified via the Iowa Surveillance, Epidemiology, and End Results cancer registry. After specific exclusion criteria were applied, a nested case-control comparison of 138 cases with 2,814 randomly selected noncases was undertaken. Intakes, in the upper-most quartile, of 11 vegetable and fruit groups, as well as of the nutrients beta-carotene and vitamin C, were explored. High intakes of all vegetables and fruit, all vegetables, and green leafy vegetables were each associated with an approximate halving of risk: age-, smoking-, and
energy-adjusted odds ratios (ORs) were 0.49 (95% confidence interval,
0.28-0.86), 0.50 (95% confidence interval, 0.29-0.87), and 0.45 (95% confidence
interval, 0.26-0.76), respectively. A lower lung cancer risk was also seen for
all fruit (adjusted OR = 0.75 for high consumption), high vitamin C vegetables
and fruit (OR = 0.75), carrots (OR = 0.71), and brocolli (OR = 0.72) and for the
nutrients beta-carotene (OR = 0.81) and vitamin C (OR = 0.81) (all 95%
confidence intervals included 1.0). Lung cancer risk was unrelated to
consumption of the three food groups defined as "high-carotenoid"
(beta-carotene, lutein, and lycopene) and tomatoes. In an analysis stratified by
histological type of lung cancer, the strongest inverse associations for
vegetables and fruit were seen for large cell carcinoma. Analysis by smoking
status showed the inverse associations for most vegetable and fruit groups with
lung cancer risk to be stronger for exsmokers than for current smokers. Results
from the stratified analyses must be interpreted with caution because of the
small number of cases in each stratum.

469. Cancer Res 1992 Apr 1;52(7 Suppl):2060s-2066s
Does beta-carotene explain why reduced cancer risk is associated with vegetable and fruit intake?
Ziegler RG, Subar AF, Craft NE, Ursin G, Patterson BH, Graubard BI
Environmental Epidemiology Branch, National Cancer Institute, Bethesda, Maryland 20892.

Increased intake of vegetables, fruits, and carotenoids and elevated blood
levels of beta-carotene are consistently associated with reduced risk of lung
cancer in epidemiologic studies. Epidemiologic research also suggests that
carotenoids may reduce the risk of other cancers, although the evidence is less
extensive and consistent. The simplest explanation is that beta-carotene is
protective. However, the possible roles of other carotenoids, other constituents
of vegetables and fruits, and associated dietary patterns have not been
adequately explored. To evaluate these alternative hypotheses, we are
undertaking three lines of research. (a) With dietary data from the 1987
National Health Interview Survey and the 1982-1984 Epidemiologic Follow-up of
the first National Health and Nutrition Examination Study, we have determined
which food groups and nutrients are highly correlated with vegetable and fruit
intake. (b) We have developed and characterized a liquid chromatography method for optimal recovery and resolution of the common carotenoids in blood,
specifically lutein, zeaxanthin, beta-cryptoxanthin, lycopene, alpha-carotene,
and beta-carotene. (c) In a population-based case-control study of lung cancer
in white men in New Jersey, we are assessing whether estimates of the intake of the individual carotenoids might produce stronger inverse associations than
estimates of provitamin A carotenoids based on current food composition tables.

470. Am J Epidemiol 1991 Dec 1;134(11):1347-55
A case-control study of nutrient status and invasive cervical cancer. II.
Serologic indicators.
Potischman N, Herrero R, Brinton LA, Reeves WC, Stacewicz-Sapuntzakis M, Jones CJ, Brenes MM, Tenorio F, de Britton RC, Gaitan E
Environmental Epidemiology Branch, National Cancer Institute, Bethesda, MD.

A study of 387 cases and 670 controls from four Latin American countries
evaluated the hypothesis that lower serum levels of eight micronutrients were
associated with a higher risk of invasive cervical cancer. The serologic
analyses were restricted to a sample of subjects with stage I and II disease to
minimize effects of the disease on the serologic markers. Ninety-four percent of
eligible subjects donated blood samples, which were analyzed for carotenoids,
retinol, and tocopherols by high-pressure liquid chromatography. Cases did not
differ significantly from controls in mean serum levels of retinol,
cryptoxanthin, lycopene, alpha-carotene, lutein, or alpha-tocopherol. The mean
level of beta-carotene was lower and the mean level of gamma-tocopherol was
higher among cases as compared with controls. After adjustment for age, study
site, sexual and reproductive behavior, socioeconomic status, screening
practices, detection of human papillomavirus types 16/18, cholesterol, and
triglycerides, a trend of decreasing risk was associated with higher levels of
beta-carotene (p for trend = 0.05), with the adjusted odds ratio decreasing to
0.72 for the highest versus the lowest quartile. beta-Carotene results were
similar by stage of disease, which argues against an effect of disease
progression on nutrient values. Unexpectedly, increasing risks were observed as
the level of gamma-tocopherol increased (odds ratio = 2.09; p for trend = 0.03);
however, levels were higher among stage II cases as compared with stage I cases, suggesting a metabolic alteration resulting from the disease process. The
concordance in the strength and direction of the blood and dietary results,
presented in the accompanying report (Herrero R, Potischman N, Brinton LA, et
al., American Journal of Epidemiology 1991;134:1335-46), supports a role for
beta-carotene or foods rich in beta-carotene in the etiology of cervical cancer.
This study also indicates that simultaneous analysis using serologic and dietary
nutrient indicators allows better discrimination of the association.

 



column header
Sign Up for Life Extension's FREE email newsletter Health Concerns
Products
Magazine
spacer
Calorie Restriction Mimetic Formula
Network Solutions SecuredBetter Business Bureau Accredited BusinessLife Extension Track Record5-Star Rated Fish Oil SupplementLife Extension Royal Treatment Customer ServiceLearn About our VIP AutoShip ProgramCustomer Satisfaction GuaranteedDirect Marketing Association Member

Home | Membership | Products | Magazine | Health Concerns | News | About Us | Legal Notices | Privacy Policy | Site Map


All Contents Copyright © 1995-2010 Life Extension Foundation® All rights reserved.

*These statements have not been evaluated by the FDA. These products are not intended to diagnose, treat, cure, or prevent any disease. The information provided on this site is for informational purposes only and is not intended as a substitute for advice from your physician or other health care professional or any information contained on or in any product label or packaging. You should not use the information on this site for diagnosis or treatment of any health problem or for prescription of any medication or other treatment. You should consult with a healthcare professional before starting any diet, exercise or supplementation program, before taking any medication, or if you have or suspect you might have a health problem. You should not stop taking any medication without first consulting your physician.