In fact, eating walnuts is indeed beneficial to the brain, but not because of the so-called "form to supplement form", but its rich nutrients.
A study in the Lancet journal eClinicalMedicine affirmed the positive significance of walnuts for brain supplementation.
The study, conducted a six-month randomized controlled intervention in 771 adolescents aged 11-16 years in Spain, found that children who ate walnuts for more than 100 days (not consecutive days) experienced increased attention and mobility intelligence (fluid intelligence) and improved attention deficit hyperactivity disorder (ADHD) symptoms.
In addition to brain supplementation, many studies have shown other benefits of walnuts for the body.
The international authoritative nutrition journal "Nutrients" analyzed the association between walnut consumption and mortality risk.
The study found that eating more than 5 servings of walnuts per week was associated with a 1.3-year increase in healthy life expectancy, a 14% reduction in the risk of all-cause mortality, and a 25% reduction in cardiovascular mortality compared to those who did not eat walnuts.
Another systematic review and meta-analysis involving 13 trials in the US, Europe, and Asia showed that a daily intake of 15 g to 99 g of walnuts was associated with a reduction in serum total cholesterol, total triglycerides, and LDL cholesterol. Dyslipidemia is considered to be an important risk factor for cardiovascular disease, the world's number one killer.
The reason why walnuts are so good is because of their own high nutritional value.
Walnuts are one of the world's "four big" dried fruits, and the highest content in walnut kernels is fat, followed by protein, carbohydrates and dietary fiber.
Although it is high in fat, it is mostly unsaturated fatty acids (known as "good fats"), and its 9% α-linolenic acid content is its unique advantage compared to other nuts.
α-linolenic acid is not only one of the key components of nerve cell membranes, but also helps improve cognitive function, supports brain health, and has a positive effect on maintaining the health of the cardiovascular system.
α-linolenic acid can also be partially converted into DHA, which is known as brain gold.
The outer film of walnut kernels is rich in vitamin E, polyphenols and other antioxidants, which are important for delaying aging and reducing cell damage.
Although walnuts are good, they should be eaten in moderation, with reasonable combinations, and avoid overeating.
Although walnuts are packed with nutrients, eating them in moderation is key due to their high calorie content. The Dietary Guidelines for Chinese Residents suggest that healthy adults can consume 50-70 grams of nuts per week, that is, an average of about 10-15 grams per day, which translates to about 2-3 walnuts per day.
Try to choose unprocessed, unshelled walnuts. Keeping walnuts in their natural state allows them to retain their nutritional value to the maximum. Avoid choosing walnuts that have been heat-treated or added with sugar, salt, etc., to avoid excessive calories.
Some people may not be advised to consume walnuts due to specific health conditions or allergies.
Walnuts have always had the reputation of "longevity fruit" and "golden medicinal fruit", which has positive significance for promoting mental activity and regulating glucose and lipid metabolism.
Resources:
[1] Tindall A， Kris-Etherton P， Petersen K. Replacing Saturated Fats with Unsaturated Fats from Walnuts or Vegetable Oils Lowers Atherogenic Lipoprotein Classes Without Increasing Lipoprotein(a). The Journal of Nutrition. 2020; 150(4)：818-825.
[2] Alshahrani SM， Mashat RM， Almutairi D， Mathkour A， Alqahtani SS， Alasmari A， Alzahrani AH， Ayed R， Asiri MY， Elsherif A， Alsabaani A. The Effect of Walnut Intake on Lipids： A Systematic Review and Meta-Analysis of Randomized Controlled Trials. Nutrients. 2022 Oct 23; 14(21)：4460.
[3] Pinar-Martí A， Gignac F， Fernández-Barrés S， Romaguera D， Sala-Vila A， Lázaro I， Ranzani OT， Persavento C， Delgado A， Carol A， Torrent J， Gonzalez J， Roso E， Barrera-Gómez J， López-Vicente M， Boucher O， Nieuwenhuijsen M， Turner MC， Burgaleta M， Canals J， Arija V， Basagaña X， Ros E， Salas-Salvadó J， Sunyer J， Julvez J. Effect of walnut consumption on neuropsychological development in healthy adolescents： a multi-school randomised controlled trial. EClinicalMedicine. 2023 Apr 6; 59：101954.