Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2008 Nov 19:7:33.
doi: 10.1186/1475-2891-7-33.

Vitamin E supplementation and pneumonia risk in males who initiated smoking at an early age: effect modification by body weight and dietary vitamin C

Harri Hemilä  1 , Jaakko Kaprio
Affiliations

Vitamin E supplementation and pneumonia risk in males who initiated smoking at an early age: effect modification by body weight and dietary vitamin C

Harri Hemilä et al. Nutr J. .

Abstract

Background: We had found a 14% higher incidence of pneumonia with vitamin E supplementation in a subgroup of the Alpha-Tocopherol Beta-Carotene Cancer Prevention (ATBC) Study cohort: participants who had initiated smoking by the age of 20 years. In this study, we explored the modification of vitamin E effect by body weight, because the same dose could lead to a greater effect in participants with low body weight.

Methods: The ATBC Study recruited males aged 50-69 years who smoked at least 5 cigarettes per day at the baseline; it was conducted in southwestern Finland in 1985-1993. The current study was restricted to 21,657 ATBC Study participants who initiated smoking by the age of 20 years; the median follow-up time was 6.0 years. The hospital-diagnosed pneumonia cases were retrieved from the national hospital discharge register (701 cases).

Results: Vitamin E supplementation had no effect on the risk of pneumonia in participants with body weight in a range from 70 to 89 kg (n = 12,495), risk ratio (RR) = 0.99 (95% CI: 0.81 to 1.22). Vitamin E increased the risk of pneumonia in participants with body weight less than 60 kg (n = 1054), RR = 1.61 (1.03 to 2.53), and in participants with body weight over 100 kg (n = 1328), RR = 2.34 (1.07 to 5.08). The harm of vitamin E supplementation was restricted to participants with dietary vitamin C intake above the median.

Conclusion: Vitamin E supplementation may cause harmful effects on health in certain groups of male smokers. The dose of vitamin E used in the ATBC Study, 50 mg/day, is substantially smaller than conventional vitamin E doses that are considered safe. Our findings should increase caution towards taking vitamin E supplements.

Trial registration: ClinicalTrials.gov NCT00342992.

PubMed Disclaimer

Figures

Figure 1
Figure 1
Vitamin E supplementation and pneumonia risk in subgroups of the ATBC Study participants who started smoking at ≤ 20 years. A) Weight < 60 kg and dietary vitamin C intake > 75 mg/day (n = 468). B) Weight ≥ 100 kg and dietary vitamin C intake > 95 mg/day (n = 613). Nelson-Aalen cumulative hazard functions for vitamin E and no-vitamin E groups are shown. Each step indicates one case of pneumonia. For the difference between the two survival curves, the logrank test gives A) P = 0.0021 and B) P = 0.0020. The survival curves are cut at 7.2 years because the number of participants declines abruptly thereafter. At 6-years of follow-up there were remaining 114 and 126 participants in A), and 146 and 162 participants in B), in the vitamin E and the no-vitamin E groups, respectively.
See this image and copyright information in PMC

References

    1. Ford ES, Ajani UA, Mokdad AH. The prevalence of high intake of vitamin E from the use of supplements among U.S. adults. Ann Intern Med. 2005;143:116–120. - PubMed
    1. Ames BN, Shigenaga MK, Hagen TM. Oxidants, antioxidants, and the degenerative diseases of aging. Proc Natl Acad Sci USA. 1993;90:7915–7922. doi: 10.1073/pnas.90.17.7915. - DOI - PMC - PubMed
    1. Finkel T, Holbrook NJ. Oxidants, oxidative stress and the biology of ageing. Nature. 2000;408:239–247. doi: 10.1038/35041687. - DOI - PubMed
    1. HOPE and HOPE-TOO Trial Investigators Effects of long-term vitamin E supplementation on cardiovascular events and cancer: a randomized controlled trial. JAMA. 2005;293:1338–1347. doi: 10.1001/jama.293.11.1338. - DOI - PubMed
    1. Miller ER, Pastor-Barriuso R, Dalal D, Riemersma RA, Appel LJ, Guallar E. Meta-analysis: high-dosage vitamin E supplementation may increase all-cause mortality. Ann Intern Med. 2005;142:37–46. - PubMed

Associated data