Oh nuts. Many people don't fully appreciate all the health benefits we get from them. Nuts are excellent for our heart health by: lowering our LDL (bad) cholesterol, reducing risk of blood clots, and reducing risk of coronary heart disease. They do this by providing a Power 12 List: 1) Omega-3 Fatty Acids, 2) L-arginine, 3) Fiber, 4) Vitamin E, 5) Plant Sterols, 6) Unsaturated Fats, 7) Vitamin K, 8) Vitamin B6, 9) Folate, 10) Vegetable Protein, 11) Calcium, & 12) Magnesium.
In addition to heart health, nuts contribute to health in other ways. They can reduce your risk of diabetes, Parkinson's disease and dementia, macular degeneration, and improve your mood (e.g. walnuts improve serotonin levels in your brain, similar to antidepressant medications).
The best nuts: walnuts, hazlenuts, almonds, cashews, pistachios, pecans, and even peanuts (although not really a nut, but rather a legume). Also, the way in which you eat them matters. Raw or dry-roasted are the best ways and offer equal nutritional value. Oil-roasted nuts have more fat and calories. Try to avoid nuts made with salt--or at minimum, make sure sea salt instead of regular salt is used. If you are a food pyramid follower, nuts belong in the "meat" group.
The nut craze doesn't come without precaution. Please don't go nuts (pun intended) eating these, as just a handful is approximately 200 calories. Everything in moderation. The reason they are so calorically dense is because of nuts' high fat content. These fats are the healthy ones though, polyunsaturated and monounsaturated.
Pregnancy nuts: there is debate about whether consumption of peanuts and other nuts during pregnancy increases the risk that a child will develop a nut allergy or asthma OR conversely, exposure protects a child from developing an allergy or asthma. Be sure to read scientific sources of literature and look at the date of publication. A lot of press came out after the July 15, 2008 article I referenced above and here, but more recent science says the opposite. Be sure to consult with your physician on this.
*photo courtesy of nuthealth.org