Eat more tomatoes to improve blood vessels, and three tomatoes a day is the most suitable.
From "Poison" to Food
Tomatoes are loved by people all over the world, but this kind of fruit and vegetable originated in Peru is called "Wolf Peach" because of its early bright colors. /kloc-In the 6th century, an English duke brought tomatoes to Europe, but they only used them as decorations. Later, a painter risked his life and found it non-toxic and delicious. Since then, tomatoes have officially appeared on the dining table. Tomatoes were introduced to China in the Ming Dynasty. Because of the foreign language meaning of "vermicelli", it was called "sweet persimmon" at that time. Botanists later discovered that it belongs to Solanaceae and is also called tomato like eggplant. According to foreign organic planting websites, there are four main types of tomatoes: common tomatoes, cherry tomatoes, shrub tomatoes and steak tomatoes. The common tomato types in the market are mainly conventional tomatoes and cherry tomatoes, or both are cultivated varieties.
People at home and abroad continue to study the effects of tomatoes on health. In the above study, the research team divided healthy people with cholesterol values between 120 and 160 mg/dL into two groups. They eat tomatoes with high lycopene content and tomatoes without lycopene. After eating raw food for 12 weeks, they found that the bad cholesterol of the former was significantly reduced and the blood lipid was significantly improved. The latest issue of Food Science and Nutrition also published an article pointing out that tomatoes or tomato products (such as tomato juice) can lower blood pressure and cholesterol levels, which is beneficial to cardiovascular health.
Bad cholesterol is low density lipoprotein cholesterol, and good cholesterol is high density lipoprotein cholesterol. Both of them are "transporters" in the human body, but the former transports lipids in blood to cells, while the latter transports lipids in cells and blood to the liver for storage or decomposition. Under normal circumstances, both of them are unimpeded, but "bad" bad cholesterol means that when its transport volume increases (that is, the content of bad cholesterol increases), the lipid in the cell will accumulate, which will trigger a series of inflammatory reactions and eventually lead to atherosclerosis. Hardening and leading to plaque formation.
In addition to improving cardiovascular and cerebrovascular functions, tomatoes have also been proved to be beneficial to preventing diseases and improving bones. Xi Jiaotong University in China and the University of South Australia in Australia studied the effects of carotenoids on senile cataracts, and found that people who eat tomatoes and citrus fruits rich in carotenoids have lower risk of senile cataracts. Research by Leibniz Institute of Environmental Medicine in Germany shows that eating tomatoes regularly can effectively resist the adverse effects of ultraviolet rays, reduce wrinkles and prevent skin cancer. Xu, deputy chief physician of central hospital of wuhan Clinical Nutrition Department, said that the above research mainly focused on the special ingredients of tomatoes. At present, the clinical advice to patients is a more balanced food. It is not recommended to eat only tomatoes to prevent some diseases or assist some treatments. Red, orange and yellow nutrients are concentrated together.
The acidity of tomatoes comes from organic acids, and the sweetness comes from a small amount of sugar. It is rich in vitamin C, potassium, dietary fiber and antioxidants. The vitamin C content of tomato per 100g is about 5 times that of apple.
Lycopene is the main antioxidant in tomatoes. Some clinical biochemical scientists give lycopene to experimental mice at the recommended dose for humans. The results showed that the bone mineral density of the experimental mice increased obviously, and the sex hormones such as estrogen in the body also increased. Australian researchers have found that if you consume more than 25 mg of lycopene (including tomato sauce, tomato juice and raw tomatoes) every day, the bad cholesterol level of cholesterol level can be reduced by about 10%.
Yi Zhu, an associate professor of food science and nutritional engineering at China Agricultural University, said that if they consume 5- 10 mg of lycopene every day, everyone can get health benefits. The content of lycopene in different types of tomatoes is 0.8 to 4.2 mg per 100 g. According to the median of 2 mg, you need to eat 3 medium-sized tomatoes every day to meet your needs. According to the recommended intake of vegetables in the Dietary Guidelines for China Residents (20 16), the recommended intake of tomatoes and melons (including tomatoes) is about150g.
There are many kinds of tomatoes, and different colors have different nutrients. The American Horticultural Society discussed the influence of color difference on the nutritional value of tomatoes: red tomatoes are rich in lycopene; Tomato color has high lycopene content. Orange tomatoes are rich in tocopherol, which is an antioxidant and helps to prevent skin diseases such as eczema and psoriasis. Yellow tomatoes are usually high in content. Polyphenols help lower cholesterol and blood pressure. Different tomatoes have different nutritional components, but researchers say that no matter which kind of tomato is helpful to improve the overall health index, it is not necessary to stick to a certain color when choosing, but to be as diverse as possible.
Don't choose any additives for tomato products.
Many people have such a question: Is it better to eat tomatoes raw or cooked? Are tomato products such as ketchup also beneficial?
Yi Zhu said that the sweetness of tomatoes is a little sour. Eating raw can not only stimulate appetite, but also integrate vitamins, dietary fiber and other nutrients into the body. However, fat-soluble nutrients such as lycopene and carotene need to be mixed with oil. For better absorption. Therefore, putting tomatoes in a pot and frying them with a little oil is beneficial to the absorption of lycopene and carotene. In this case, the loss of vitamin C is also very small, and the content of nutrients (such as dietary fiber and minerals) that are not affected by temperature will not change. Therefore, tomatoes can be eaten raw or cooked. If cooked food can better meet the demand, in order to better absorb nutrients such as lycopene and carotene, but pay attention to the amount of fat added, one teaspoon is enough.
Tomato sauce is also a common seasoning, sweet and sour, very delicious. Experts remind that when choosing tomato sauce, you must first check whether it is pure tomato sauce or tomato sauce with sugar, salt and edible spices. The latter is a condiment with seasoning function. When cooking, pay attention to reducing the amount of sugar and salt. Similar to pure tomato juice, squeezed pure tomato juice retains all the nutrients of tomato, and the cell wall is destroyed, and the amount of lycopene dissolved is also greater, so it is a beverage with higher nutritional value. However, it should be noted that when buying bottled tomato juice in the supermarket, you must carefully observe the ingredient list. Many of them are based on adding sugar, salt and other ingredients to tomato juice. This drink is almost the same as a sweet drink.
Xu reminded some people to be cautious and eat less tomatoes. 1. Patients with gastroesophageal reflux and patients prone to abdominal pain. Gastroesophageal reflux is largely related to diet. Organic acids in tomatoes may cause gastric acid reflux and cause discomfort. Immature tomatoes contain a lot of alkaloids. Although the content of lycopene will decrease with maturity, people with sensitive gastrointestinal tract will still feel uncomfortable if they eat a lot of lycopene. It is suggested that such people eat cooked tomatoes and avoid eating tomatoes on an empty stomach or raw. 2. People who are allergic to tomatoes. Tomato is one of the known allergens. If eaten or touched by susceptible people, it may lead to sneezing, eczema, rash and so on. 3. People who take anticoagulants. Because of the high content of vitamin K in tomatoes, a large amount of food will reduce the anticoagulant effect of drugs, and a small amount of food is usually no problem.