The main nutrients in tomatoes are vitamins, the most important and abundant of which is lycopene, a type of carotene. In recent years, scientists have made many new breakthroughs in the research on the health effects of lycopene. Its proven benefits include: possessing unique antioxidant capabilities to eliminate free radicals in the human body that cause aging and disease; preventing the occurrence of cardiovascular diseases; stopping the progression of prostate cancer, and effectively reducing the risk of developing cancers of the pancreas, rectum, larynx, oral cavity, and breast.
The lycopene content in tomatoes is significantly influenced by factors such as the variety, color, ripeness, sweetness, and even the season in which they are grown. Yellow tomato varieties contain very little lycopene, only about 0.3 milligrams per 100 grams. Red varieties, on the other hand, have a much higher content, typically 2-3 milligrams per 100 grams, with some reaching as high as 20 milligrams. Generally, the redder the tomato, the higher the lycopene content. Unripe and semi-ripe green tomatoes have relatively low levels. There are also pink tomatoes on the market, whose lycopene content is not as high as that of red ones.
The lycopene content in tomatoes is negatively correlated with their soluble sugar content. This means that the less sweet a tomato is, the higher its lycopene content. Additionally, tomatoes grown in the summer have higher lycopene levels. This is primarily because abundant summer sunlight and longer exposure to light significantly increase the lycopene content. In contrast, tomatoes grown in greenhouses during the winter have lower lycopene levels.
An adult can meet their body's daily lycopene needs by consuming 100-200 grams of tomatoes. However, many people prefer eating tomatoes raw, which is not conducive to lycopene absorption because it is a fat-soluble vitamin. Its health benefits are better realized after heating and cooking with oil. Furthermore, since lycopene is prone to decomposition when exposed to light, heat, and oxygen, cooking should avoid prolonged high heat to preserve more of its nutritional value. When cooking, covering the pot tightly and adding a little vinegar can help protect it from being destroyed by oxygen.