Garlic and onions
Both garlic and onions belong to the narcissus family . The varieties in this family can be used in cooking, in addition to that they contain active biological compounds, and the functional characteristics of the types that can be eaten from this family have been studied extensively in the laboratory, including: garlic , onions, shallots , and shallots , garlic chives ,  and onions several types vary in size, flavor, color, and shape, but the most common varieties is red onion, Yellow, and white, As for garlic, it is considered a bulb crop that has a strong smell, and it is believed that its origin dates back to Kazakhstan, Uzbekistan and western regions of China, and garlic can be used in many forms, such as: fresh garlic, garlic powder, and aged garlic extract. All of them have a positive health-promoting effect. 
Benefits of garlic and onions
Both garlic and onions contain many sulfur compounds that mainly contain active elements of the amino acid derivative cysteine, which break down into a variety of thiosulfinates and polysulfides by making an enzyme. Allinase during the extraction process, and the analyzed substances are volatile substances present in garlic oil and onions, and they have anti-diabetic and antibiotic properties, in addition to their ability to reduce cholesterol levels and enhance the fibrinolytic process that It reduces the occurrence of thrombosis in blood vessels, and many other biological processes.  The following are some studies that were conducted on eating garlic and onions separately, and others that were conducted on garlic and onions together:
- A study published in the Journal of Food and Chemical Toxicology in 2005 was conducted to study the effect of onion and garlic juice on biochemical rates, enzyme activity, and fat oxidation in diabetic mice , as they were given 1 milliliter of onion or garlic juice per 100 grams of weight. The body daily, for a period of four weeks, and the results showed that onion and garlic juice has an antioxidant effect , reduces blood sugar levels, and may reduce the liver and kidney damage caused by diabetes in mice. 
- A study published in The American Journal of Clinical Nutrition in 2006 showed that increased intake of vegetables from the narcissistic family is associated with a reduced risk of several types of common cancers in humans. 
- A study was published in Nutrition and Cancer in 2020, in which cases of breast cancer were identified in a group of 314 women, aged 30 to 79 years, and another group of 346 women without a history of cancer other than non-melanoma (melanoma). In English: nonmelanoma skin cancer), and their diet was monitored, and it was found that the high intake of onions and garlic, which includes even spices, was associated with a lower risk of breast cancer in women. In the end, the results of the study suggest that eating a large amount of onions and garlic from It may reduce the risk of breast cancer in this group. 
- A study published in the journal Atherosclerosis was conducted on the effect of the essential oils in garlic and onions on rabbits that were given a diet rich in cholesterol, and the results showed that a decrease in the rate of high cholesterol levels in animals that were given this diet for a period of three months, as a result of eating onion oil and garlic, as well The study indicated that garlic oil has a greater effect compared to onion oil, in addition to this, it is possible for these oils to reduce the accumulation of fat in the aorta in rabbits. 
- A study in mice, published in Biological Trace Element Research in 2009, showed that onion and garlic extract has an effect that reduces the risk of liver exposure to oxidative damage caused by mice exposure to Cadmium, as onion and garlic extract helps mitigate the effects. Significantly negative cadmium, and this effect is likely due to reduced fat oxidation and enhanced body defense with antioxidants, Another study conducted on mice, published in Biometals in 2008, found that onion and garlic extract may have a damaging effect on cadmium, which is known to be a toxic substance that causes damage to the kidneys through oxidative stress, by reducing the levels of peroxidative fats. In English: Lipid peroxidation) in the kidneys, and it also enhances the antioxidant effect, and this extract may be useful nutrients to reduce cadmium damage to the kidneys. 
General benefits of garlic
Garlic contains more than 33 sulfur compounds, in addition to many enzymes, and contains 17 amino acids, and minerals such as selenium ,  and studies support garlic's possession of potential antibacterial benefits, as well as antioxidant properties, which may help Reducing free radicals, It is worth noting that a 3-gram clove of garlic contains almost no calories, and eating a whole head of garlic adds only 4 calories to the diet, and given that it is not consumed in large quantities during the day, it does not affect the calculation of calories, nor Eating it makes a noticeable difference to the amount of daily food intake, and carbohydrates are the source of calories in garlic, but they are very low, and therefore the calories in it are low, and garlic provides a few vitamins and minerals, as one clove provides a small amount of vitamin C and manganese. . 
General benefits of onions
Onions are rich in nutrients, as they contain high levels of vitamins, minerals and antioxidants, and are low in calories, and onions are a good source of vitamin C, vitamin B6, and manganese, as they contain less calcium, magnesium, phosphorus, and iron , Folate, potassium, the antioxidant quercetin, and sulfur, In addition, onions are a source of fiber, as the fiber makes up 0.9 to 2.6% of the fresh weight of onions, depending on the type, and onions are rich in a type of soluble fiber called fructans, and it is rich in plant compounds and antioxidants, And compounds that contain sulfur, and it should be noted that the different colors of onions such as yellow and red have a greater amount of antioxidants compared to white onions. 
To read more about the benefits of onions, you can refer to the article What are the benefits of onions for the body
Are there benefits of onions and garlic for pregnant women
Onions and garlic contain many of the nutrients mentioned previously, except that there are no studies that show the benefits of eating onions and garlic for pregnant women, but onions are classified among the safe products, but it is advised to avoid eating large quantities of it other than those in food, because it has not been proven how safe it is to eat Large quantities of it,  As for garlic, it is often considered safe when consumed during pregnancy in the quantities usually found in food, but eating it in large quantities or medicinally, such as those found in extracts, or nutritional supplements during pregnancy and lactation, is likely to be unsafe for health. 
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