Dietary intake levels, lycopene

Lycopene derived from a fungal biomass of Blakeslea trispos, suspended in sunflower oil at a concentration of 20% w/w, was tested for subchronic toxicity at concentrations of 0%, 0.25%, 0.50%, and 1.0% in rats for 90 days (Jonker et al., 2003). No evidence of toxicity of lycopene at dietary intake levels up to 1.0% was observed in this study. The authors suggest the noobserved-effect level (NOEL) for this lycopene to be 1.0% in the diet, the highest dietary concentration tested. McClain and Bausch (2003) published... 

Carotenoids and prostate cancer — Numerous epidemiological studies including prospective cohort and case-control studies have demonstrated the protective roles of lycopene, tomatoes, and tomato-derived products on prostate cancer risk other carotenoids showed no effects. " In two studies based on correlations between plasma levels or dietary intake of various carotenoids and prostate cancer risk, lycopene appeared inversely associated with prostate cancer but no association was reported for a-carotene, P-carotene, lutein, zeaxanthin, or p-cryptoxanthin. - Nevertheless, a protective role of all these carotenoids (provided by tomatoes, pumpkin, spinach, watermelon, and citrus fruits) against prostate cancer was recently reported by Jian et al. ... 

Carotenoids and urino-digestive cancers — On the whole, findings from epidemiological studies did not demonstrate a protective role of carotenoids against colorectal, gastric, and bladder cancers. Indeed, most prospective and case-control studies of colorectal cancer showed no association with dietary intake or plasma level of most carotenoids. - Only lycopene and lutein were shown to be protective against colorectal cancer. Otherwise, findings from the ATBC study s showed no effect of P-carotene supplementation on colorectal cancer. 

Among 27 prospective and case-control studies, 16 reported inverse associations between some carotenoids and CVDs, taking plasma or serum concentration as carotenoid biomarkers (11 of 16 studies), dietary intake (5 of 16 studies), or adipose tissue level (1 of 16 studies). With regard to the findings from the studies based on CVD risk, only two of seven presented significant inverse associations of carotenoids, particularly lycopene and P-carotene, whereas five studies of nine showed inverse correlations between myocardial infarcts and lycopene and/or P-carotene the others presented no associations. ... 

Epidemiological data on carotenoids and cerebral infarcts or strokes indicate a protective effect of P-carotene and lycopene. Indeed, the Basel prospective study, the Kuopio Ischaemic Heart Disease Risk Factor study, and the Physicians Health Study " have shown an inverse correlation between carotenoid plasma level and risk of stroke. In the same way, Hirvonen et al. demonstrated, in findings from the ATBC cancer prevention stndy, an inverse association between P-carotene dietary intake and stroke. However, clinical data on carotenoids and stroke are nonexistent and they are needed to confirm this possible protective effect of carotenoids on stroke. 

Lycopene levels in plasma and human tissues reflect dietary intake. In a study, when subjects consumed a tomato-free diet for 2 weeks, their lycopene levels dropped significantly (Rao and Agarwal, 1998a). Ingested lycopene is... 

Kanetsky, P.A., Gammon, M.D., Mandelblatt, J., Zhang, Z.F., Ramsey, E., Dnistrian, A., Norkus, E.P., Wright, Jr., T.C. 1998. Dietary intake and blood levels of lycopene association with cervical dysplasia among non-Hispanic, black women. Nutr Cancer. 31 31-40. 

Other dietary factors implicated in prostate cancer include retinol, carotenoids, lycopene, and vitamin D consumption.5,6 Retinol, or vitamin A, intake, especially in men older than age 70, is correlated with an increased risk of prostate cancer, whereas intake of its precursor, [3-carotene, has a protective or neutral effect. Lycopene, obtained primarily from tomatoes, decreases the risk of prostate cancer in small cohort studies. The antioxidant vitamin E also may decrease the risk of prostate cancer. Men who developed prostate cancer in one cohort study had lower levels of l,25(OH)2-vitamin D than matched controls, although a prospective study did not support this.2 Clearly, dietary risk factors require further evaluation, but because fat and vitamins are modifiable risk factors, dietary intervention may be promising in prostate cancer prevention. 

Since there was a significant positive correlation between serum lycopene levels and dietary lycopene intake as determined from the estimated food... 

---