Heart disease affects nearly 30% of the U.S. population. A major contributor to heart disease is high cholesterol, occurring in nearly 100 million Americans. In addition to cholesterol-lowering drugs, treatment includes decreasing total intake of fats, saturated fats and cholesterol. However, several clinical trials show that a diet low in saturated fats and high in unsaturated fats may be more effective than reducing total fat intake.
Nut consumption has been looked down upon by the healthcare industry due to the caloric and fat content. Growing epidemiological evidence is slowly changing this negative image. Nuts are rich in the following:
- plant proteins
- unsaturated fats
- minerals (copper, magnesium, potassium)
- vitamins (folic acid, niacin, vitamin E and B6)
FDA Recommends Eating Nuts to Reduce Risk of Heart Disease
The U.S. Food and Drug Administration issued a health claim stating that eating 1.5 oz/day of specific nuts may reduce heart disease risk. The specific nuts identified include:
A large body of evidence has demonstrated the protective effects of eating nuts. One study found that eating 1.5 oz of walnuts six days a week significantly reduced low-density lipoprotein (LDL) cholesterol and total cholesterol, decreasing risk of heart disease by approximately 18.6%. Another study showed pistachios can significantly increase high-density lipoprotein (HDL) cholesterol while decreasing total cholesterol and LDL. Pistachios contain ß-sitosterol, which is a phytosterol known to decrease cholesterol. Additionally, pistachios contain a large amount of arginine, which seems to relax blood vessels by increasing nitric oxide (NO) levels.
Nuts Help Reduce Heart Disease Risk in Type 2 Diabetes
Type 2 diabetes is known to drastically increase heart disease risk. One study focused on heart disease risk in women with type 2 diabetes who consumed nuts. The study looked at thousands of women between the years of 1980 and 2002. The results showed that eating at least five servings a week of nuts and peanut butter significantly lowered heart disease risk and heart attacks by up to 44% among women with type 2 diabetes. Of course, weight gain is always a concern, especially in diabetes. Fortunately, research has shown that eating nuts has no significant effect on weight.
Recently, a review of 25 studies focusing on the effects of nuts in cholesterol levels was completed. Total cholesterol and LDL were reduced, with no effect on HDL. Additionally, nuts decreased triglycerides in people with hypertriglyceridemia. However, the cholesterol-lowering effects were greater in people who started the study with higher LDL levels and those with a lower body mass index (BMI). Typically, intestinal absorption of cholesterol is reduced in obesity. Plant sterols in nuts work by reducing intestinal cholesterol absorption, dampening the cholesterol-lowering effects of nuts in obesity.
Nuts are slowly being recognized as a protective factor in heart disease. While studies tend to be small, mounting evidence suggest nuts may be advantageous when added onto traditional cholesterol therapies. Always speak with a doctor and pharmacist prior to starting or stopping any dietary or drug regimen.