Watzl Bernhard, Kulling Sabine E, Möseneder Jutta, Barth Stephan W, Bub Achim
Institute of Nutritional Physiology, Federal Research Centre for Nutrition and Food, Karlsruhe, Germany.
Am J Clin Nutr. 2005 Nov;82(5):1052-8. doi: 10.1093/ajcn/82.5.1052.
Whether different intakes of vegetables and fruit modulate immunologic markers is currently not known.
We investigated the effects of low, medium, and high intakes of vegetables and fruit on markers of immune functions, including nonspecific markers of inflammation.
In a randomized controlled trial, nonsmoking men consumed a diet that included < or = 2 servings/d of vegetables and fruit for 4 wk. The subjects were then randomly assigned to 1 of 3 groups to consume 2 servings/d, 5 servings/d, or 8 servings/d of carotenoid-rich vegetables and fruit for another 4-wk period. Plasma concentrations of vitamins C and E and carotenoids were measured. The assessment of immunologic and inflammatory markers included the number and activity of natural killer cells, secretion of cytokines, lymphocyte proliferation, and plasma C-reactive protein concentrations.
The high intake (8 servings/d) of vegetables and fruit significantly increased total carotenoid concentrations in plasma compared with the low intake (2 servings/d; week 4 compared with week 8), whereas concentrations of vitamins C and E did not differ between week 4 and week 8. Immunologic markers were not significantly modulated. In contrast, C-reactive protein was significantly reduced at week 8 in the subjects who consumed 8 servings/d of vegetables and fruit compared with those who consumed 2 servings/d.
In healthy, well-nourished, nonsmoking men, 4 wk of low or high intakes of carotenoid-rich vegetables and fruit did not affect markers of immune function. However, a high intake of vegetables and fruit may reduce inflammatory processes, as indicated by the reduction of plasma C-reactive protein.
目前尚不清楚蔬菜和水果的不同摄入量是否会调节免疫标志物。
我们研究了低、中、高摄入量的蔬菜和水果对免疫功能标志物的影响，包括炎症的非特异性标志物。
在一项随机对照试验中，不吸烟的男性连续4周食用蔬菜和水果摄入量≤2份/天的饮食。然后将受试者随机分为3组，在接下来的4周内分别食用2份/天、5份/天或8份/天富含类胡萝卜素的蔬菜和水果。测量血浆中维生素C、维生素E和类胡萝卜素的浓度。免疫和炎症标志物的评估包括自然杀伤细胞的数量和活性、细胞因子的分泌、淋巴细胞增殖以及血浆C反应蛋白浓度。
与低摄入量（2份/天）相比，高摄入量（8份/天）的蔬菜和水果显著提高了血浆中总类胡萝卜素的浓度（第4周与第8周相比），而第4周和第8周之间维生素C和维生素E的浓度没有差异。免疫标志物没有受到显著调节。相比之下，与食用2份/天蔬菜和水果的受试者相比，食用8份/天蔬菜和水果的受试者在第8周时C反应蛋白显著降低。
在健康、营养良好的不吸烟男性中，4周低或高摄入量的富含类胡萝卜素的蔬菜和水果不会影响免疫功能标志物。然而，如血浆C反应蛋白降低所示，高摄入量的蔬菜和水果可能会减少炎症过程。
