The Nutritional Composition and Health Benefits of Lincang Walnuts.
An area of particular interest is the role walnuts may play in brain health. One small human intervention study showed some effects on mood, although only in males.30 A small cross-sectional
study showed improvements in working memory in an older female cohort at high cardiovascular disease risk. However, walnut supplementation for 2-years was shown not to affect cognition in
healthy, free-living elderly people.
However, in this study, there were some indications that walnuts might delay cognitive decline in subgroups at higher risk for dementia. In addition to human
trials, animal trials indicate other potential health benefits, including other effects on brain function. Walnut diets improved motor performance and cognitive ability in older mice, but effects were dependent on amounts consumed, with the moderate intake being optimal. These authors subsequently showed anti-inflammatory effects of walnuts in microglia, which could have benefits in protecting neurodegeneration.
Soil composition may also affect the nutritional composition and the nature of Lincang soils has been studied. Carbonatite is the main soil in the Yunnan walnut planting area, especially brick-red soil and limestone. The brick-red soil has good hydrothermal conditions, and the parent materials are mostly granite, phyllite, gneiss, sand shale, and old alluvial laterite. The limestone soil is rich in organic matter and nutrients, with a good structure. The concentration of serotonin in walnuts was determined by LCMS. Lincang walnuts were significantly higher in serotonin, particularly compared with the Californian sample.
Adv Food Technol Nutr Sci Open J. 2020; 6(1): 29-41. doi: 10.17140/AFTNSOJ-6-166