Nutritional value and health benefits of pumpkin

pumpkin

Pumpkin, scientific name Cucurbita spp., is an annual herbaceous vine plant belonging to the Cucurbitaceae family. It has strong adaptability to the environment and can grow well in gaps that are not suitable for farming. It is easy to cultivate and has high yield. It is one of the main vegetables in summer and autumn in my country. Pumpkin resources are very abundant, and it is resistant to storage, easy to transport, and easy to process. For a long time, due to insufficient understanding of the nutritional value of pumpkin, people have always regarded it as an inferior vegetable. Except for a small amount of direct consumption, most of it is processed as feed, which has prevented this vegetable with great development prospects and application value from being well developed and utilized. In recent years, studies have found that pumpkin is not only rich in nutrition, but also has a variety of dietary health care effects and medicinal value [1]. It is considered a special health food. The comprehensive development and utilization of pumpkin products are increasingly valued by China and developed countries around the world. The development of pumpkin series products has a broad international and domestic market and a very attractive prospect. At present, my country is the second largest pumpkin producer in the world. It has many advantages such as sufficient raw materials and cheap labor, and has the ability to occupy the international market [1, 5]. However, the production scale of pumpkin series products in my country is small and the output is low, which is far from meeting the needs of the international market. This article discusses the nutritional value and health benefits of pumpkin, aiming to help people better understand and utilize pumpkin.

Nutritional value of pumpkin

Pumpkin is rich in nutrients (Table 1). The fruit contains carbohydrates (including starch, glucose, pectin, fructose, pentosan, mannitol, other dietary fibers, etc.), vitamins, proteins, multiple amino acids, fats and other ingredients. Among the three major heat-producing nutrients, pumpkin is mainly carbohydrates and has a very low fat content, making it a very good low-fat food [2, 5]. Pumpkin is rich in inorganic salts and trace elements, which play an extremely important role in maintaining human health. Pumpkin also contains a lot of potassium, calcium, and magnesium, but a low sodium content. It is rich in trace elements such as selenium, iron, and zinc. As a high-calcium, high-zinc, high-iron, and low-sodium food, pumpkin is particularly suitable for middle-aged and elderly people and patients with hypertension, and is beneficial for preventing osteoporosis and preventing and treating hypertension. The amino acid analysis of pumpkin powder by Huo Xiaoqiong et al. [5] showed that pumpkin contains 17 kinds of amino acids required by the human body, among which the essential amino acids such as lysine, leucine, isoleucine, phenylalanine, and threonine are relatively high. Its carotene content is 8 to 20 times that of watermelon, making it a high-quality source of vitamin A. In addition, pumpkin also contains trigonelline, cucurbitine, soluble fiber and mannitol and other effective ingredients. The calories produced by pumpkin are equivalent to wheat and corn, the protein content is equivalent to kidney beans and agar, the vitamin A content is equivalent to tomatoes, and the vitamin C content is higher than cucumbers.

Pumpkin's health benefits

In ancient my country, there are records of pumpkin's health-care effects. In Compendium of Materia Medica, Li Shizhen put pumpkin together with Ganoderma lucidum, saying that pumpkin can nourish the middle qi, liver qi, heart qi, lung qi, and essence qi. It is suitable for people with chronic illness, weak spleen and stomach, shortness of breath, fatigue, poor appetite, abdominal distension, edema, and oliguria. Recent studies have also shown that pumpkin has a variety of health-care effects, especially as a special nutritional health food for preventing and treating diabetes.

3.1 Blood sugar lowering function

Pumpkin is one of the traditional blood sugar lowering foods in my country. In the 1970s, Japan reported the use of pumpkin powder to treat diabetes. Over the years, many researchers have been committed to the study of pumpkin prevention and treatment of diabetes, and proposed that pectin, cyclopropyl amino acids, and trace elements zinc and chromium (Cr) in pumpkin may play a major role in pumpkin prevention and treatment of diabetes [7]. The chromium content of pumpkin ranks first among all vegetables. Cr is one of the essential trace elements for the human body. Trivalent chromium is the active center of glucose tolerance factor (GrP), which can stimulate glucose uptake and help maintain glucose tolerance. Chromium deficiency in the human body is one of the causes of hypertension, diabetes, and coronary heart disease. Chromium can not only inhibit the formation of malignant tumors in the body, but also promote the release of insulin in the body, so that diabetic patients can secrete insulin normally, which is very effective in lowering blood sugar. Cyclopropyl amino acids can promote insulin secretion and enhance the sensitivity of insulin receptors. At the same time, they can activate glucose enzymes, accelerate the conversion of glucose, and reduce blood sugar concentration [9]. In addition, pumpkin is rich in pectin, which can reduce blood sugar and blood insulin levels after meals; at the same time, pectin has a satiety effect, which can improve the patient's hunger, thereby controlling and assisting in the treatment of diabetes and its complications, and is a good food therapy for diabetics. In addition, Zhang Yongjun et al. [9, 11] isolated pumpkin polysaccharides from pumpkin and preliminarily determined the hypoglycemic mechanism of pumpkin polysaccharides through animal experiments on mice. Clinical trials have shown that diabetic patients who eat 100g of pumpkin powder every day have different degrees of improvement after 10 days of examination, and some have even recovered. At present, pumpkin powder has been regarded by experts as the "nemesis" of diabetes.

3.2 Lipid-lowering function

Pumpkin polysaccharides were isolated and extracted from pumpkins, and animal experiments have shown that pumpkin polysaccharides can significantly reduce TG, Tch and LDL in the serum of diabetic mice [4]. TG, Tch and LDL in serum are factors that promote atherosclerosis, especially elevated LDL, which is a risk factor for myocardial infarction. The chemical composition of pumpkin polysaccharides contains a large amount of uronic acid and a large number of negatively charged acidic genes. Therefore, it is speculated that pumpkin polysaccharides may have a similar effect to phospholipids, which can remove cholesterol and prevent arteriosclerosis. In addition, at physiological pH, negatively charged pumpkin polysaccharides can bind to LPL and release it from the arterial wall into the blood, promoting the degradation of chylomicrons and VLDL, and preventing and treating cardiovascular diseases such as hypertension. [7, 13]

3.3 Cancer prevention and treatment effects

Pumpkin contains some physiologically active substances such as alkaloids, trigonelline, and cucurbitine, which can eliminate and catalyze the decomposition of carcinogenic nitrosamines and effectively prevent and treat cancer[10].

3.4 Detoxification, liver and kidney protection

Pumpkin is rich in pectin, which has excellent adsorption properties. It can bind and effectively eliminate bacterial toxicity and the effects of heavy metals and radioactive elements in the body. It has the effect of resisting environmental toxins and has a significant therapeutic effect on patients with gastrointestinal ulcers. Pumpkin contains potassium salt, water and a small amount of sodium salt, which can enhance the secretion capacity. When the prostate and liver are inflamed, it has a good effect on accelerating the dissolution of kidney stones and bladder stones. In addition, pumpkin powder is also effective in treating hepatitis, cirrhosis, kidney disease and other diseases, because yellow-green vegetables such as pumpkin contain ingredients that can destroy harmful substances such as pesticides and nitrites in food, which can help patients with weakened liver and kidney function and enhance the regeneration capacity of their liver and kidney cells. According to recent studies by the Japanese Cancer Prevention Center, eating yellow-green vegetables such as pumpkin and cauliflower every day can reduce the incidence of lung cancer and reduce the mortality rate of lung cancer. [2, 10]

3.5 Antioxidant and vision protection functions

Pumpkin is rich in vitamin E and carotene. Vitamin E has a strong antioxidant effect, which can effectively protect the body from damage by some oxygen free radicals and peroxides, and may have a certain anti-aging effect. Carotene can be converted into vitamin A (VA) in the body, which has important physiological effects on the human body. VA plays an important role in protecting eyesight, preventing eye diseases, maintaining the health of human epithelial tissues, and promoting the growth and development of children. At the same time, VA has an important physiological role in maintaining normal vision and eyesight, promoting bone development, and preventing cancer. As a source of VA in food, pumpkin food is more economical than animal food (such as liver, egg yolk, etc.) [1, 8]. It is reported that among people who often eat pumpkin, those over 80 years old can still maintain good eyesight and can read newspapers without wearing glasses.

3.6 Function of assisting in the treatment of prostatitis

Pumpkin seeds and pumpkin seed extracts have the pharmacological effect of relieving prostatitis and treating benign prostatic hypertrophy, but the effect is poor when used alone. If it is used in combination with other natural plants, the effect on prostate disease will be better. Pumpkin seed oil is rich in unsaturated fatty acids such as linoleic acid and linolenic acid, which can prevent prostate cancer and enhance male sexual function.

3.7 Other functions

Pumpkin is rich in citrulline, which can expel parasites such as roundworms, tapeworms, ginger worms and schistosomes, and has a certain effect on the treatment of schistosomiasis and late-stage schistosomiasis ascites. Pumpkin seeds are also rich in soybean oil acid, which can nourish brain cells, remove sediments on the inner wall of blood vessels, improve brain function, and improve cerebral blood circulation. The inorganic salts and trace elements in pumpkin play an extremely important role in maintaining the health of the body, and have the effects of preventing obesity, treating chronic osteomyelitis, curing asthma, protecting pregnancy, and promoting lactation in parturients.