Your browser doesn't support JavaScript. Please upgrade to a modern browser or enable JavaScript in your existing browser.
Skip Navigation U.S. Department of Health and Human Services www.hhs.gov
Agency for Healthcare Research Quality www.ahrq.gov
AHRQ Home | Questions? | Contact Us | Site Map | What's New | Browse | Información en espańol | E-mail UpdatesE-mail Updates
www.ahrq.gov

You Are Here: AHRQ Home > Clinical Information > U.S. Preventive Services Task Force (USPSTF) > Guide to Clinical Preventive Services, 2001-2004 > Counseling: Vitamin Supplementation to Prevent Cancer & Cardiovascular Disease > Summary of the Evidence

Table 1a. Randomized Controlled Trials of Vitamin Supplementation to Prevent CancerA

Study, Publication Setting/Population Treatment Duration of Followup;
Followup Rate
Beta-carotene
Hennekens, 19968
Physicians' Health Study		 22,071 U.S. male physicians aged 40-84 years; no history of:
  • Cancer.
  • Myocardial infarction.
  • Stroke.
  • Cerebral ischemia.
  • Noncompliance in run-in phase.
 50 mg beta-carotene on alternate days; cointervention with 325 mg aspirin on alternate days in 2 x 2 factorial design Mean 12 years; 99.99%
Alpha-Tocopherol Beta-Carotene (ATBC) Study Group, 19949 SW Finland; 29,133 male smokers aged 50-69 years 20 mg/day beta-carotene; 50 mg/day alpha-tocopherol in 2 x 2 factorial design 5-8 years; median 6.1 years
Greenberg 199411
Polyp Prevention Study		 6 U.S. gastroenterology clinics; 864 subjects; 79% male <80 years; at least one polyp 25 mg/day beta-carotene  vs placebo; cointervention with combination of 1 g/day vitamin C and 400 mg/day vitamin E or placebo in 2 x 2 factorial design 3 years between year 1 and year 4 colonoscopies (mean 36.6 months; no difference between groups)
MacLennan, 199512
 Australian Polyp Prevention Study		 Australian gastrointestinal clinics; 424 subjects; 67% male; aged 30-74 years; at least one polyp 20 mg/day beta-carotene; fat reduction (25% of total energy target); wheat bran fiber (25 g/day of finely milled raw wheat bran) in 2 x 2 x 2 factorial design 2-4 years
I-M Lee, 199910
Women's Health Study		 39,876 U.S. female health professionals >45 years 50 mg beta-carotene on alternate days vs placebo; cointervention with 100 mg aspirin or placebo on alternate days and 600 IU vitamin E or placebo on alternate days in 2x2x2 factorial design. Beta-carotene study terminated early. 4 years
DeKlerk, 199815
Mesothelioma Prevention Study		 1024 Australian male (92%) and female (8%) asbestos mine workers; mean age 57; 21% current smokers, 52% ex-smokers, 27% never smokers 30 mg/day beta-carotene (n=512) or 25,000 IU/day retinol (n=512); No placebo group Through 5/95; mean FU 4.5 years
Vitamin E
ATBC Study Group, 19949 SW Finland; 29,133 aged 50-69 years male smokers 20 mg/day beta-carotene; 50 mg/day alpha-tocopherol in a 2 x 2 factorial design 5-8 years; median 6.1 years
Multivitamin and antioxidant combinations
Greenberg, 199411
 Polyp Prevention Study		 6 U.S. gastroenterology clinics; 864 subjects; 79% male; <80 years; at least one polyp 1 g/day vitamin C and 400 mg/day vitamin E vs  placebo; cointervention 25 mg/day beta-carotene or placebo in a 2 x 2 factorial design 3 years between year 1 and year 4; colonoscopies (mean=36.6 months, no difference between groups)
Omenn  199614
CARET		 4060 West Coast male asbestos workers; 14,254 U.S. male and female heavy smokers (66% male overall) 30 mg/day beta-carotene and 25,000 IU/day retinol or placebo 5.5 years
McKeown-Eyssen 199825 Toronto hospital;  185 subjects; 60% male; at least one polyp 400 mg/day vitamin C and 400 mg/day vitamin E or placebo 2 years
Ponz de Leon 199726
 Italian Polyp Prevention Study 		Italy; 255 subjects; % male not known; at least one polyp Antioxidant vitamins (30,000 IU vitamin A, 70 mg vitamin E, 1 g vitamin C per day); lactulose (crystalline powder or syrup); placebo 36 months

A For more details about the trials, go to Appendix 3.

Note: ATBC indicates Alpha-Tocopherol Beta-Carotene;g, gram; mg, milligram; n, number; FU, followup; NR, not reported; CARET, Beta-Carotene and Retinol Efficacy Trial.

Table 1b. OutcomesB of Randomized Controlled Trials of Vitamin Supplementation to Prevent Cancer

Study, Publication Lung Cancer Prostate Cancer Breast Cancer Colon Cancer Other Cancer All-cause Mortality
Beta-carotene
Hennekens, 1996 8
Physicians' Health Study		 Incidence:
0.93 (0.69-1.25; NS)		 Incidence:
 0.99 (0.88-1.11)		 NR Colon/Rectum Incidence:
0.96 (0.78-1.18) 		Incidence:
Stomach: 0.90 (0.49-1.67)
Pancreas: 1.38 (0.79-2.40)
Brain: 0.81 (0.48-1.36)
Melanoma: 0.88 (0.63-1.22)
Leukemia: 0.83 (0.53 -1.30)
Lymphoma: 1.07 (0.79-1.45)
Bladder: 1.51 (1.02-2.24)
Thyroid: 8.00 (2.05-31.23)
All cancer mortality:
1:02 (0.88-1.17)		 1.01 (0.93-1.10)
ATBC Study Group, 19949 Incidence:
1.19 (1.03-1.36)		 Incidence:
1.23 (0.95-1.60)		 NR Incidence:
1.05 (0.75-1.47)
Adenomatous polyps recurrence: 
   0.98 (0.71-1.35)		 Pancreatic incidence:
0.75 (0.49-1.14) 
Pancreatic mortality:
0.81 (0.53-1.26)		 1.08 (1.01-1.16)
Greenberg, 199411
Polyp Prevention Study		 NR NR NR Adenomatous polyps recurrence:
1.01 (0.85-1.20)		 NR 1.03 (0.82-1.30)
MacLennan, 199512
Australian Polyp Prevention Study		 NR NR NR Incidence:
1.5 (0.9-2.5)c		 NR NR
I-M Lee, 199910
Women's Health Study		 Incidence:
1.43 (0.82-2.48)		 NR Incidence:
1.01 (0.81-1.24)		 Incidence:
0.99 (0.62-1.60)		 Incidence:
Uterus: 1.15 (0.69-1.91;NS)
Ovary:  1.33 (0.73-2.43)
Thyroid: 0.75 (0.32-1.74;NS)
Bladder: 0.83 (0.27-2.57)
Brain: 0.67 (0.20-2.20)
Pancreas: 1.50 (0.45-4.94)
Cervix: 0.67 (0.13-3.33)
Stomach: 0.99 (0.10-9.58)
All cancer: 1.03 (0.89-1.18)
All cancer mortality:
1.11 (0.67-1.85)		 1.07 (0.74-1.56)
DeKlerk, 199815
Mesothelioma Prevention Study		 Incidence:
0.66 (0.19-2.32)		 NR NR NR Malignant mesothelioma incidence:
0.24 (0.07-0.86)
Other cancer mortality:
0.97(0.24-3.90)		 0.56 (0.33-0.95)
Vitamin E
ATBC Study Group, 19949 0.98 (0.86-1.12) Incidence:
0.68 (0.53-0.88)
Mortality:
0.59 (0.35-0.99)		 NR Incidence:
0.78 (0.55-1.09)
Adenomatous polyps recurrence:
1.66 (1.19-2.32)		 Cancer mortality:
1.05
Pancreatic cancer incidence:
1.34 (0.88-2.05) 
Pancreatic cancer mortality:
1.11 (0.72-1.72)		 1.02 (0.95-1.09)
Multivitamin and antioxidant combinations
Greenberg,  199411
Polyp Prevention Study		 NR NR NR Adenomatous polyps recurrence:
1.08 (0.91-1.29)		 NR NR
Omenn, 199614
CARET		 Incidence:
1.28 (1.04-1.57)
Mortality:
1.46 (1.07-2.00)		 Incidence:
1.01 (0.80-1.27)		 Incidence:
0.78 (0.55-1.12)		 Incidence:
1.02 (0.70-1.50)		 Incidence:
Urinary/bladder: .08 (0.69-1.70)
Head/neck: 1.26 (0.73-2.19)
Leukemia: 2.18 (0.95-5.03)
Lymphoma: 0.91 (0.42-1.98)
Mesothelioma: 1.52 (0.66-3.52)		 1.17 (1.03-1.33)
McKeown-Eyssen, 199825 NR NR NR Adenomatous polyps recurrence:
0.86 (0.51-1.45)		 NR NR
Ponz de Leon, 199726
Italian Polyp Prevention Study		 NR NR NR Adenomatous polyps recurrence:
0.16 0.04-0.46)		 NR NR

A For more details about the trials, go to Appendix 3.
B All confidence intervals .95%.
c Unadjusted odds ratio.

Note: ATBC indicates Alpha-Tocopherol Beta-Carotene;g, gram; mg, milligram; n, number; FU, followup; NR, not reported; CARET, Beta-Carotene and Retinol Efficacy Trial.

Return to Document

 
AHRQ Advancing Excellence in Health Care