NO - Besoin d'assistance

Observational epidemiological surveys (WG 3) page 63
_________________________________________________________________________________________
Part 4: Tomatoes and tomato products, lycopene, other
carotenoids, vitamins C and E and age-related eye diseases.
Cataract is one of the major causes of blindness throughout the world and is particularly
important in developing countries (Schwab, 1990). The cataract can be defined as
dysfunctions of the eye lens, which collect and focus light on the retina, leading to its
opacification. Besides metabolic disorders, opacification is usually associated with old age.
Another age-related eye disease is the macular degeneration. It affects a region situated in the
middle of the retina called fovea leading to a lost of visual acuity. Delaying the appearance of
these disease in old people would enhance the quality of life by decreasing the disability and
reducing its costs estimated to 5 billion $ in the United States. The biological mechanisms for
both disease involve oxidative processes resulting from chronically exposure of eyes to light
and oxygen and leading to damages of lens proteins which can then aggregate and precipitate
( Taylor et al., 1993) or to accumulation of oxidised polyunsaturated fatty acyls which are
very high in the retina membranes (Noell, 1980) and of lipofuscin, a complex made by
oxidised products (Iwasaki and Inomata. 1988). In the following tables, epidemiological
studies on the prevalence of antioxidants including vitamin C, vitamin E and carotenoids on
cataract and age related macular degeneration will be summarised.
4-1 Tomatoes, Fruit and other Vegetables and Cataract.
Studies were carried out by Jacques and Chylack (1991) on only 77 subjects with senile
cataract and 35 controls. A food frequency questionnaire was used to estimate dietary intake
for the one year period preceeding entry into the study. Subjects who consumed fewer than
3.5 servings of fruit or vegetables per day had an increased risk of both cortical (OR = 5.0,
p