Walnuts are the fruit of the Juglans regia tree. Practical to always have with you, tasty and full of energy, walnuts are the perfect snack, they enrich the breakfast muesli and make preparations such as bread and cakes even more delicious. But walnuts are also a precious source of health properties for the well-being of the heart, brain and gut, let's see better.
Walnuts, properties
Walnuts are an important source of omega 3 fatty acids. These fatty acids are often lacking in Western diet but play an essential role in various biological processes such as inflammation and coagulation and result able to regulate glucose tolerance, blood pressure and the nervous system. Not only that, walnuts also provide vitamins, such as vitamin E, and mineral salts, such as magnesium, calcium, potassium and manganese (Petrovic Oggiano et al, Nutrients, 2020). Thanks to the substances contained, walnuts are protective for the heart. In fact, thanks to their content in alpha linolenic acid, which is a fatty acid of the omega 3 type, they perform an antiarrhythmic action and, due to the presence of particular substances called phytosterols, reduce bad LDL cholesterol even up to 16% (Kris Etherton et al, J Nutr, 2014). In addition to this, walnuts are also anti-inflammatory, help improve the function of the endothelium, which is the lining of blood vessels, and are able to reduce blood pressure by 2-3 mmHg (Berryman et al, J Nutr, 2013). Walnuts also contain antioxidant substances, such as carotenoids, tocopherol and ellagitannins, which show an interesting antitumor action (Ros et al, Curr Opin Clin Nutr Metab Care, 2018). Finally, walnuts also improve the health of the microbiota, which is the set of bacteria that live in our intestines. In fact, the daily intake of 40 grams of walnuts for 8 weeks showed to promote the so-called good bacteria, such as those that produce butyric acid. Butyric acid is a fatty acid that, while being produced in the colon, also has effects on the cardiovascular system, since it helps to reduce blood pressure (Bamberger et al, Nutrients, 2018).
Walnuts, brain and mood
Walnuts are also beneficial for cognitive functions and mood, so much that the topic certainly deserves a dedicated section. In fact, walnuts are rich in antioxidants, including vitamin E and polyphenols, and fatty acids and for this reason they are an important ally for brain health, helping to counteract, or delay in case of high risk, degenerative diseases such as Alzheimer's (Pparmi et al, Nutrients, 2016 - Sal Vila et al, Am J Clin Nutr, 2020). Not only that, walnuts also play an important role against depression by providing substances such as melatonin, which has been found to be useful in improving mood and also fighting insomnia. The alpha linolenic acid contained in walnuts is not only beneficial for the heart, as we saw in the previous paragraph, but also for the brain. In fact, this fatty acid is a precursor of other substances, including DHA, which participates, among other functions, also in neuroplasticity, in the regulation of serotonin and in the transmission of neurosignals (Pparmi et al, Nutrients, 2016).