There are different types of walnuts which have been cultivated for thousands of years. The most common walnut, referred to as the Persian walnut, originated in India and its regions surrounding the Caspian Sea. The ancient Romans introduced the walnut in the majority of European countries around 300 AD. Ever since it has been introduced by the ancient Romans, walnuts are grown all over Europe and the rest of the world. The walnut tree has been highly revered. Besides growing walnuts, the walnut tree is also used as shelter, for medicine, food, dye and lamp oil. White and black walnuts are native to North America. They originate from the Appalachian area and Central Mississippi. While and black walnuts played an important role in the lifestyles and diets of the early colonial setters and in the lives of the Native American Indians. While walnuts currently grow all over the world, the largest commercial producer of walnuts in the world is China. China produces an average of 350,000 metric tons of walnuts each year. The second largest commercial produced of walnuts is the United States with an average of 294,000 metric tons of production a year. The area in which walnuts grow in the United States is California. About 90% of the United States’ walnut production comes from California. More specifically, they grow in the Sacramento Valleys and San Joaquin. Next in line of production are Turkey, Iran and Ukraine.
Walnuts mostly grow during the winter period in December, but nowadays walnuts are available all year round and can be found in almost every supermarket. They are a great addition to a meal if you want some extra crunch, flavor and nutrition to it. Moreover, walnuts are also a great source of all important omega-3 fatty acids making them one of the healthiest nuts. The walnut kernel is made up of two bumpy lobes. The color of the lobes is off white and are covered in a thin, light brown skin. The walnut could be compared to an abstract butterfly since the two halves of the walnut are also partially attached to each other. The kernels are covered by a round brown shell which is pretty hard. There are different ways to open the shell of a walnut. You can either use a knife, or a nutcracker to break the shell open. The Persian walnut, currently referred to as the English walnut, is the most popular walnut and it has a thin shell and can easily be opened with a nutcracker. The black walnut has a thicker shell and is more difficult to break open with a nutcracker. Moreover, the black walnut also has a more pungent distinctive taste compared to the English walnut. The white walnut, on the other hand, has a more sweet and oilier taste compared to the black walnut and the English walnut. Nevertheless, it is relatively difficult to find white walnuts in the supermarket since they are not widely available. The different types of walnut do not only differ in taste and look, but they also each have a unique nutrient composition.
Most research done on walnuts related to the benefits they have on the heart and the circulatory system. There are a few studies which have emphasized the effects of walnuts on the vascular reactivity. This relates to the ability of the blood vessel to respond to different stimuli in a healthy manner. In order for the blood vessels to respond to these stimuli in a healthy manner, our cardiovascular system should be functioning optimally. Not just the cardiovascular system itself, but all its different aspects should be functioning well. Some of the aspects include the proper blood composition, the presence of anti-inflammatory nutrients and the presence of antioxidants in the blood. Researches have determined that walnuts have a desirable impact on all of the aspects of the cardiovascular system. While there have been some studies which state that walnuts have a positive effect on blood pressure, there are others which state that this is not necessarily the case. It is suspected that these mixed results are related to the mineral composition in the different types of walnuts. Researchers have also indicated that there is a positive relationship between healthy blood pressure and the intake of certain minerals. Some of these minerals include calcium, potassium and magnesium.
As mentioned earlier, walnuts contains antioxidant and anti-inflammatory nutrients. It is for this reason that a lot of research has been done of the effects of walnuts on cancer. Research has shown that the different types of walnuts have measurable anti-cancer benefits. It is indicated that the antioxidant properties in walnuts contribute to a lower risk of chronic oxidative stress. The anti-inflammatory properties, on the other hand, help lower the risk of chronic inflammation. When chronic oxidative stress and chronic inflammation are combined they pose a greater threat to the development of cancer cells in the body. Thus, the consumption of walnuts does not only contribute to the cardiovascular system but also has properties which lower the risk of cancer development. The types of cancer which have been studied most in relation to the consumption of walnuts are breast cancer and prostate cancer. Research has indicated that the intake of walnuts contributes to a reduced risk of both these types of cancer. The results are based on consuming an average of 3 ounces a day. The evidence is stronger for prostate cancer. Research with regards to walnut intake and prostate cancer has involved humans and its results are therefore more reliable compared to the studies of breast cancer. Research on breast cancer mostly involved rats and mice. This means that in order for the results to be more viable, more research needs to be done in the future to confirm the results.
Walnuts are also recommended for people trying to lose weight. They are considered to be a desirable food item which help prevent obesity and supports weight loss. Most people are often surprised to hear that walnuts contributes to weight loss. They often believe that walnuts are a high-calorie food and are high in fat, and therefore contribute to weight gain and obesity. It is true that the overconsumption of foods which are high in fat and in calories contribute to weight gain and could eventually lead to obesity. Nevertheless, obesity is not solely dependent on the intake of high-fat and high calorie products. Obesity has been identified as also involving chronic, unwanted inflammation. As mentioned earlier, walnuts contain anti-inflammatory nutrients and are therefore unique in that sense. They also contain high amounts of omega-3 fatty acids such as phenolic acids, phytonutrients and many other anti-inflammatory nutrients. The benefits of these nutrients can overshadow the high-fat risk of walnuts. This is exactly what has been done by numerous studies analyzing the relation between the consumption of walnuts and its link to obesity. While it is always possible to over-consume walnuts, it is recommended to have an average of 1 to 3 ounces a day in order to keep a right balance. By eating the right portions and not over-consuming walnuts, it is unlikely that walnuts contribute to weight gain and obesity.
When buying walnuts in the supermarket which are still in their shell, try buying those which feel a bit heavy for their size. Their shells should not be stained, cracked or pierced. If they are then this is often a sign of mold development. When mold has developed in the walnut, they should not be eaten since they are considered to be unsafe for consumption. Most supermarkets sell shelled walnuts in prepackaged containers or in bulk bins. When purchasing walnuts, make sure you also check the expiry date on the package to make sure they are fresh. If you want to ensure that the walnuts you are buying are of good quality and are fresh, it is also possible to buy them at a nut store or a delicacy store. Moreover, it is important to avoid buying those walnuts which look shriveled or rubbery. In order to be sure that the walnuts you are buying are fresh it is also possible to smell the walnuts. By smelling the walnuts before purchasing them you ensure that they are not rancid. Additionally, it is important that walnuts are stored properly. Since they are extremely high in poly-unsaturated fat, they are very perishable. If you are buying shelled walnuts, they should be stored in an airtight container. It is recommended that the airtight container is stored in the refrigerator. In the refrigerator the walnuts can last up to six months. They can also be stored in the freezer. In the freezer the walnuts can last up to one year. Unshelled walnuts, on the other hand, do not necessarily need to be stored in the refrigerator. They can be kept in a cool, dry and dark place. When stored in a place like this, they can stay fresh up to six months. They can, however, also be stored in the refrigerator. Also in the refrigerator can they be stored up to six months.
