The pollution of human environment and aliment has many points of contact. Foreign materials penetrating into the chain of foodstuffts are significant risk for heart-vascular and cancer diseases. Many nutritive factors (vitamin C, tocopherols, carotenes, indigestible fibrous materials, selenium, indoles and many other up to now non-indentified materials from vegetable, fruit, mushrooms) reduce the negative impact of degraded human environment. Propagation of rational aliment often gets to paradox situation. Although coarse-fibred cereals appear as a rich resource of fibrous materials, but at the same time they may be a resource of toxical cadmium. Vegetable and fruit have high content of vitamin C, pectine and other biologically valuable materials, but at the same time they may contain unacceptable high amount of nitrates and residues of various pesticides. Insufficiency of detoxicational factors in aliment significantly increases the toxical effect of foreign materials. One of the most important protective factor is ascorbic acid – vitamin C – its lack negatively influences the function of central detoxical enzyme, cytochrome P-450 in liver cell. Vitamin C blocks also the formation of oxygen radicals and cancerogenous nitrosamines. The aliment of inhabitants of ČSFR is characteristical by permanently low receipt of vitamic C the lack of which is intensified in winter and in spring. In addition to it in our territory the negative effects of degraded human environment and other unbalances are cumulated in aliment. Such a negative synergism is probably the main reason of the rapid increase of untimely mortality of heartvascular diseases and cancer and together with this also the stagnation of average span of life of inhabitants in ČSFR.