Snacking on walnuts may protect against heart disease. Spanish scientists have shown that walnuts can protect against the hardening of the arteries that occurs when you eat fatty foods. Fat molecules trigger an inflammatory response that reduces the elasticity of the arteries, over time this contributes to their hardening and can lead to heart disease. Healthy volunteers were given a high-fat meal of salami, cheese sandwiches and full-fat yoghurt with either five teaspoons of olive oil or eight shelled walnuts. Both the olive oil and the walnuts helped reduce inflammation in the arteries, but ultrasound examinations revealed that the arteries of those eating the walnuts retained more elasticity and flexibility. Walnuts are rich in an amino acid called arginine, which is important for the production of a substance that helps keep arteries flexible. Walnuts also contain antioxidants and alpha-linolenic acid, a plant-based omega-3 fatty acid, which can help protect against heart disease.
Cortés B, Núñez I, Cofán M, Gilabert R, Pérez-Heras A, Casals E, Deulofeu R and Ros E. 2006. Acute Effects of High-Fat Meals Enriched With Walnuts or Olive Oil on Postprandial Endothelial Function. Journal of the American College of Cardiology. 48 (8) 1666-1671.