This Nut Halts Dementia We know nuts are good for your health. They are packed with nutritional fiber, healthy antioxidants, and anti- inflammatory substances. A new study published in the American Journal of Clinical Nutrition has found this one type of nut to slow the progression of dementia in at- risk seniors. The research involved 636 participants aged between 63 and 79 from California and Barcelona. At the beginning of the study, they were declared cognitively healthy. The researchers divided them into two groups: one consumed between 30 and 60 grams of walnuts per day, and the other consumed none.