Natural History
The pecan is a very large (up to 55m) tree in the hickory family, called Carya illinoinensis. It is native to central and southern USA but is now cultivated worldwide. Although native Americans and early American colonial settlers made good use of wild pecan tree produce, it was only cultivated as a crop in the 1880s. It can live and bear fruit for up to 300 years.
Health Benefits
Pecans are a rich source of vitamin E, magnesium, calcium, potassium, zinc and fibre. They contain more than 19 vitamins and minerals, and 25g of pecans provides 10% of the RDV for fibre.
Antioxidants: Pecans contain more antioxidants than any other nut, and are in the top category of foods with the highest antioxidant capacity. It has particularly high levels of vitamin E (25mg per 100g of nuts), which is itself an antioxidant and may provide neurological protection. It has been suggested from recent research that pecans may help prevent Alzheimers and Parkinson’s diseases as well as heart disease and cancer.
The vitamin E in pecans is probably also responsible for their ability to help prevent the oxidation of blood lipids, which is a contributor to heart disease.
Cancer prevention: Another notable antioxidant in pecans is the polyphenol ellagic acid, which has the added property of helping fight cancerous developments by directly inhibiting the DNA binding of certain carcinogens.
Pecans are a rich source of oleic acid, which helps suppress the activity of a gene that can trigger breast cancer. 25g of pecans provides 25% more oleic acid than 1 tablespoon of olive oil.
The type of vitamin E found in abundance in pecans – gamma-tocopherol – has the ability to kill prostate cancer cells while leaving healthy ones intact.
Cholesterol lowering: Pecans contain beta-sitosterol, a compound that helps lower cholesterol levels. They also contain other plant sterols that are known for their cholesterol lowering ability.
Gamma-tocopherol helps decrease the rate of oxidation of LDL cholesterol in the blood by up to 33%. Oxidised LDL contributes to inflammation in the arteries and can lead to cardiovascular problems.
One study compared people on a low fat diet and people on a diet enriched with pecans and their cholesterol levels. The results showed those on the pecan enriched diet lowered their total cholesterol levels by 11.3% and LDL levels by 16.5% – double the rate of the low fat diet. And no additional weight gain was recorded, despite consuming additional fats from the pecans.
