Ah…Nuts

Recently an article was published in the Archives of Internal Medicine.  This article talked about the benefits of eating nuts. Many previous studies have reported that people who eat nuts have fewer heart attacks.  This is a study that pooled the data from several studies in attempt to estimate the effect of nuts on cholesterol levels.  It also looked at other factors that may change the effect nuts have on cholesterol levels.  It looked at other factors like weight, diet and cholesterol levels.

The study found that if a person ate about 67grams of nuts a day (about 16 nuts) the total cholesterol will lower about 10 mg/dl, the LDL will lower about 10 mg/dl and triglycerides will lower about 20 mg/dl.  This is not a big change, but none of the studies lasted more than 8 weeks. HDL levels did not change with eating nuts.  It has been estimated that nut consumption reduces the risk of cardiac disease by 37%.  This is a greater reduction that you would expect if nuts only reduce heart disease by reducing cholesterol.  Nuts seem to have additional effects that lead to less heart disease.

In these studies nuts were eaten in place of other food.  When the nuts replaced food that is part of a typical Western the cholesterol lowered the most.  When nuts replaced calories in Mediterranean diet, cholesterol did not lower as much.

Heavy people did not benefit from nuts as much as people with lower weight.  This is important because heavy people have a higher risk for heart disease.  Nuts are very high in fat and eating lots of nuts in addition to a regular diet could make losing weight difficult.  So if you eat nuts it should be in place of something.  Nuts can be substituted for meat.  One serving of nuts is 1.5 oz (43g).  This study looked at the benefits from eating twice this amount or about 16 nuts in a day.  The nuts that were studied were Walnuts, Almonds, Macadamias, Pistachios, Hazelnuts, Pecans and Peanuts.  (Peanuts are not actually nuts but part of the bean or legume family and seemed to have benefits similar to true nuts.)

So nuts do seem to lower cholesterol numbers modestly.  They as well seem to reduce the risk of heart disease.  However for people that are obese it seems that the benefits are not as great as for thin people.  People frequently add nuts to their diet. However they will have a greater benefit by eating nuts instead of food like fatty cuts of red meat.  Diet is only one way of becoming healthy.  It is important to also remember the importance of exercise.  Medication can be another important tool to prevent heart disease. 

Two of the authors did receive funding from California Walnut Commission, the Almond Board of California, the National Peanut board and the International Tree Nut Council.   But that doesn’t make them bad nuts.

Archives of Internal Medicine.  Nut Consumption and Blood Lipid Levels. Vol 170 (No.9) pages 821-827.