Eat apples to lower cholesterol! Key: How to take quercetin?

“An apple a day keeps the doctor away” means that apples are rich in pectin, vitamins, quercetin and other nutrients that are beneficial to health. Eating them in moderation every day can help keep away chronic diseases. In recent years, they have even been used as one of the ingredient options for weight loss meals! However, can quercetin, a type of phytochemical that helps plants resist diseases and pests, really lower cholesterol and reduce weight when ingested by the human body?

Not just apples! Quercetin can also be found in onions, berries, and ginkgo

Among phytochemicals, quercetin is a type of flavonoid (also known as "flavonoid"), which is mainly found in the seeds, nuts, stems, and leaves of plants. In addition to apples, common edible foods include onions, tea, berries, and a variety of cruciferous vegetables, where traces of quercetin can also be found.

Onions and apples are common natural foods rich in quercetin.

In addition, the "Taichung District Agricultural Monthly" published by the Council of Agriculture and an article published by Dr. Zhang Longren of the Taichung District Agricultural Improvement Station also mentioned that quercetin is also contained in ginkgo, Hypericum perforatum, elderberry and many other medicinal plants, and is the main active ingredient of these medicinal plants. Many experimental studies have confirmed that it has health effects or therapeutic effects on the human body.

Quercetin antioxidant helps lower bad cholesterol levels

Hou Wenyi, director of the Nutrition Department of St. Martin's Hospital, said that the main function of quercetin is anti-oxidation and free radical scavenging. A review of domestic and foreign literature shows that quercetin has the effect of inhibiting lipid peroxidation, which can prevent the oxidation of low-density cholesterol (also known as bad cholesterol) and thus protect cardiovascular health. However, this type of research data comes from test tube experiments or animal experiments. Whether it can be directly applied to humans still needs to be supported by more empirical results.

Domestic research has found that heating can promote the release of quercetin in food ingredients.

So does quercetin help with weight loss? Nutritionist Hou Wenyi said that she has not seen any literature showing that quercetin can directly or indirectly help with weight control. However, if people can supplement other nutrients and dietary fiber while taking quercetin through whole grains, tubers, and fresh fruits and vegetables, and follow the principle of a balanced diet, they can naturally achieve the goal of losing weight and maintaining an ideal weight.

Don’t be greedy when supplementing quercetin. Heat the natural ingredients before eating to avoid the trouble of overdose.

It should be noted that eating more quercetin does not necessarily improve your health! Dr. Zhang Longren pointed out in the article that the intestinal absorption rate of quercetin is extremely low, only about 2%. In animal experiments, feeding mice a high concentration of quercetin at 160 mg per kilogram of body weight caused the death of half of the test mice, indicating that eating too much quercetin may not be a good thing.

In this regard, nutritionist Hou Wenyi believes that as a daily health care, there is no need to deliberately supplement quercetin through nutritional supplements. As long as you consume a balanced amount of plant-based foods every day and supplement quercetin through fresh fruits and vegetables, you don't have to worry about the potential health risks of consuming too much quercetin, and you can still promote your health.

As for how to improve the intestinal absorption rate of quercetin in natural fruits and vegetables, nutritionist Hou Wenyi said that you can refer to the principles of flavonoid food intake. Some people in China have done research on citrus fruits and found that after heating pomelo peel and kumquat peel at 120℃ and 150℃ for 90 minutes respectively, the phenolic acid content and antioxidant activity both showed an upward trend. Therefore, if people eat vegetables, they should steam, boil or heat them more often, so that they may be able to eat more natural quercetin.