A number of epidemiological studies have reported associations of beta-carotene plasma levels or intake with decreased lung cancer risk. Does beta-carotene explain why reduced cancer risk is associated with vegetable and fruit intake? Lycopene, another type of carotenoid, has also demonstrated similar effects against lung cancer.  |  Investigation of the trial findings is currently underway globally and will likely lead to a greater understanding of both the role of carotenoids in human health and of carcinogenesis itself.  |  If the β-carotene supplementation trials had not been conducted, for example, it is possible that guidelines more specific than those promoting greater consumption of vegetables and fruit might have emerged. The quantity and quality of the relevant studies, the degree of consistency among the data, the availability of a plausible mechanism or set of mechanisms, and, importantly, the beneficial (or lack of adverse) effect on other aspects of human health and disease are all highly relevant to the issue of nutrition recommendations. None of these results suggests that beta-carotene supplements cause lung cancer, but they do indicate that they don’t help to prevent it where smoking is a risk factor. 1) Data from human studies bearing on the issue were accumulated, especially from observational case-control and cohort investigations published in the 1970s and 1980s. For more than a decade, overwhelming observational evidence has existed that supports an association between lower lung cancer risk and greater consumption of carotenoid-rich foods and, specifically, higher β-carotene intake. Taking beta-carotene seems to increase the risk of lung cancer in people who smoke, people who used to smoke, people exposed to asbestos, and those who use alcohol in addition to smoking. Ultimately, abstinence from smoking remains the best way to reduce lung cancer risk. One other important issue must be considered. Eating the most beta-carotene reduced the lung cancer risk in male heavy smokers by 51 percent. Lung cancer Studies indicate that increased intake of vegetables and fruits rich in beta-carotene may decrease the risk of lung cancer. In total, these trials provide solid evidence for a relatively small adverse effect of β-carotene supplementation on lung cancer in cigarette smokers. Furthermore, a nutrient-specific guideline for β-carotene intake need not have specified source. Although dietary guidelines relevant to β-carotene intake are not discussed here in detail, they are germane as background to the case of β-carotene and lung cancer. One finding in both trials that has received less attention but is highly significant for the present purposes is that the trial participants with lower baseline β-carotene intake or β-carotene serum concentrations at baseline experienced higher lung cancer incidence during the study, independent of the intervention effects (19, 24, 25). The results indicate that beta-carotene … Increases in lung cancer may be due to the tendency of β-carotene to oxidize, and may hasten oxidation more than other food colors such as annatto. Several excellent, comprehensive reviews of this research were published, including those by Ziegler (10), Willett (11), Steinmetz and Potter (12), Block et al (13), van Poppel and Goldbohm (14), and Ziegler et al (15). Results from CARET corroborated this finding (25). Nov. 30, 2004 - Years after they stopped taking high-dose beta-carotene supplements, a group of smokers still suffer extra-high rates of lung cancer and death. However, evidence that higher fruit and vegetable intake is consistently associated with reduced cancer risk at most sites remains unchallenged. This trial studied >18000 men and women, of whom 388 developed lung cancer, with a 28% increase in lung cancer incidence in participants who received the β-carotene–retinyl palmitate combination daily for an average of 4 y compared with participants who received placebo. Other investigations should further explore the issue of vegetable and fruit consumption compared with β-carotene and carotenoid intake or serology (or, where possible, both intake and serology) and evaluate associations for dietary and supplementary sources of the micronutrients. Their results require that some caution be exercised in recommendations concerning supplemental β-carotene and argue against changing related dietary recommendations in the direction of greater nutrient specificity at this time. Eating the most beta-carotene reduced the lung cancer risk in male heavy smokers by 51 percent. The Western Electric Study, © 1999 American Society for Clinical Nutrition, The 2020 Nobel Peace Prize rewards the persistent vision of a world without hunger, famine, or malnutrition, Changes in diet quality and food security among adults during the COVID-19–related early lockdown: results from NutriQuébec, Eucaloric diets enriched in palm olein, cocoa butter, and soybean oil did not differentially affect liver fat concentration in healthy participants: a 16-week randomized controlled trial, Sugar-sweetened beverage (SSB) consumption is associated with lower quality of the non-SSB diet in US adolescents and young adults, About The American Journal of Clinical Nutrition, DIETARY GUIDELINES RELEVANT TO β-CAROTENE INTAKE. The conflicting evidence of the relation between β-carotene and lung cancer in humans serves as a poignant case study with respect to what types of evidence are sufficient to support or change a nutrition recommendation. Depending on results from additional studies such as these, further testing of supplemental β-carotene (at lower dosages in lower-risk groups), other carotenoids, or other phytochemicals may be warranted once concerns about safety have been addressed. 1999 Summer;60(3):160-165. The interpretation of more than a decade's worth of research on the relation between β-carotene from vegetables and fruit and lung cancer was suddenly brought into question by these findings. Paisley JA(1). The demonstration of these protective associations, along with other established etiologic associations with lung cancer, such as risk increasing with age, number of cigarettes smoked daily, years and pack-years of cigarette smoking, degree of inhalation, and occupational asbestos exposure, added to both the validity and the generalizability of the studies' findings. Epidemiology, Fruit, vegetables, and cancer prevention: a review of the epidemiological evidence, Epidemiologic evidence for β-carotene and cancer prevention, Diet and lung cancer risk: findings from the Western New York Diet Study, Serum beta-carotene, vitamins A and E, selenium, and the risk of lung cancer, Dietary antioxidants and the risk of lung cancer, Alpha-Tocopherol, Beta Carotene Cancer Prevention Study Group, The effect of vitamin E and beta carotene on the incidence of lung cancer and other cancers in male smokers, Effects of a combination of beta carotene and vitamin A on lung cancer and cardiovascular disease, Nutrition intervention trials in Linxian, China: supplementation with specific vitamin/mineral combinations, cancer incidence, and disease-specific mortality in the general population, Lack of effect of long-term supplementation with beta carotene on the incidence of malignant neoplasms and cardiovascular disease, α-Tocopherol and β-carotene supplements and lung cancer incidence in the Alpha-Tocopherol, Beta-Carotene Cancer Prevention Study: effects of baseline characteristics and study compliance, Risk factors for lung cancer incidence and intervention effects in CARET, the Beta-Carotene and Retinol Efficacy Trial. Studies have found that the risk of lung cancer is lower in those who have higher levels of beta carotene naturally present from the foods they eat. National Center for Biotechnology Information, Unable to load your collection due to an error, Unable to load your delegates due to an error. » New data from Canada shows a diet rich in fruits and vegetables can lower the risk by 25-35%, with male smokers seeing the biggest benefits. Some aspects of design and findings common to both the ATBC Study and CARET are the random assignment of persons at rather high risk for lung cancer because of cigarette smoking, asbestos exposure, or both; the very high serum concentrations of β-carotene achieved; and similar relative risk increases (though somewhat greater in CARET) for lung cancer incidence and total mortality. However, such a recommendation has not been made to date, in part because of the results of the studies described below. 5) The entire body of evidence was reinterpreted, with further discussion, debate, and consensus conferences in the mid-1990s. Beta-carotene: a cancer chemopreventive agent or a co-carcinogen? Some studies also showed that persons with higher blood β-carotene concentrations are at reduced risk for lung cancer compared with those with lower concentrations (14, 15). The term observational epidemiology is used to describe case-control and cohort studies. Albanes D, Heinonen OP, Taylor PR, et al. COVID-19 is an emerging, rapidly evolving situation. However, scientific evidence shows that people who eat a lot of fruits and vegetables containing beta-carotene are less likely to develop cancer and heart disease – whether or not they smoke. In contrast, the intervention results from large, controlled trials of β-carotene supplementation do not support the observed beneficial associations or a role for supplemental β-carotene in lung cancer prevention; instead, they provide striking evidence for adverse effects (ie, excess lung cancer incidence and overall mortality) in smokers. Alpha-Tocopherol and beta-carotene supplements and lung cancer incidence in the alpha-tocopherol, beta-carotene cancer prevention study: effects of base-line characteristics and study compliance. n In current smokers there is some evidence that suggests consuming foods containing vitamin C decreases the risk of lung cancer. Nutrition intervention trials in the general population of Linxian, China, investigated the effects of selected micronutrients on the incidence of esophageal cancer and total mortality in nearly 30000 men and women (primarily nonsmokers) (21). Additional research holds the key to providing us with a more complete understanding of these etiologic relations. Beta carotene is an oil-soluble nutrient, and the body may be better able to absorb it when foods are cooked, especially when they are cooked in oil. In this article, available evidence concerning the relation between β-carotene and lung cancer is reviewed and evaluated. Before changes are made to the current guidelines regarding foods, vegetables, and fruit, more definitive evidence is needed about specific micronutrients such as β-carotene. As a health and wellness educator, I would be completely remiss not to address this first. β-CAROTENE AND LUNG CANCER: WHAT IS THE EVIDENCE? This is consistent with the previously discussed observational epidemiologic studies. It was the connection between beta-carotene and lung-cancer prevention that led to some fascinating studies. It is not clear if these effects can be attributed to beta-carotene alone as the role of other . Vietnamese gac ( Momordica cochinchinensis Spreng.) Author information: (1)School of Nutrition, Ryerson Polytechnic University, Toronto, ON. Normal levels of beta-carotene from foods such as dark-green leafy vegetables, carrots, sweet potato, mango and dried apricots may help protect against cancer. Alpha-Tocopherol, Beta Carotene Cancer Prevention Study Group. However studies have shown that there is a convincing link between beta-carotene supplements and the risk of lung cancer in people who smoke cigarettes. Further, the supplementation trials suggest not only lack of benefit of β-carotene in lung cancer prevention, but possible harm in smokers from not only lung cancer but overall mortality as well. One early, widely cited paper by Peto et al (7) highlighted the potential public health significance of β-carotene and the need for controlled trials. Specifically, further evaluation of other carotenoids and phytochemicals, both in the diet and in serum, is clearly warranted because any one or more of these substances present in vegetables and fruit might be responsible for the inverse association with lung cancer. These Increased lung cancer risk among smokers who received beta-carotene was observed in two of the four trials. Cancer. Observational epidemiology should again revisit carotenoids, foods, and related biochemical factors. 11-13 In contrast, RCTs provided divergent results for other cancer sites. Epidemiological evidence for beta-carotene in prevention of cancer and cardiovascular disease. Increase Your Curcumin Intake. Furthermore, in many studies a protective association was shown for β-carotene intake in particular, and several of these related lower lung cancer risk with higher biochemical status (usually serum concentration) of β-carotene. Novel chloramphenicol sensor based on aggregation-induced electrochemiluminescence and nanozyme amplification. The deeper the color, the higher the beta-carotene content (x, x, x). Heimendinger J, Van Duyn MA, Chapelsky D, Foerster S, Stables G. Sporn MB, Dunlop NM, Newton DL, Smith JM. A 2009 study linked beta-carotene, which is naturally found in carrots, squash, spinach, and other colorful vegetables, to an increased lung cancer risk in smokers. This site needs JavaScript to work properly. [PubMed Abstract] Rautalahti MT, Virtamo JR, Taylor PR, et al. Recent randomized clinical trials of supplemental beta-carotene as a chemopreventive agent against lung cancer have had contradictory results.  |  What follows is a brief summary. The media stories that followed 10 The harmful effect of beta‐carotene supplementation on lung cancer was also well established in smokers and asbestos workers supplemented with 20–30 mg of beta‐carotene per day. Initial studies of this kind include those of Le Marchand et al (34) and Ziegler et al (35), which further explored the role of other dietary carotenoids using newly available food-composition data. BOSTON (November 1, 2016)—Beta-cryptoxanthin (BCX), a carotenoid pigment compound found primarily in plants, reduces the number and invasiveness of tumors in mouse and cell models of lung cancer, report scientists from the Jean Mayer USDA Human Nutrition Research Center on Aging at Tufts University (USDA HNRCA). This no doubt reflected, in part, the growing literature regarding the inverse association between vegetable and fruit consumption and cancer risk. The effects of vitamin E and beta carotene on the incidence of lung cancer and other cancers in male smokers. Does beta-carotene increase, rather than decrease, human lung cancer rates? 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