Nuts are unique in their position among the healthiest foods. Though technically the “fruit” of the plant, nuts lack the high sugar and water content of most fruits. Instead, they’re dry and savory and have the high amounts of protein usually reserved for meat and dairy products. There are dozens of nut varieties (though the peanut is not one of them), each of which has a unique taste and appearance. So, what are the healthiest nuts?

Classifications of Nuts

Nuts vary in appearance, texture, and taste. They are classified by the type of covering they do–or do not–have.Botanical nuts (or “true nuts”) are hard-shelled and do not split open to release seeds. Hazelnuts and chestnuts are popular botanicals.Drupes have a fleshy covering over a pit or stone. Almonds, cashews, and walnuts are examples.Gymnosperm seeds are naked and include pine nuts and ginkgo nuts.Angiosperm seeds are part of a larger fruit and include Brazil nuts, Macadamias, and peanuts.

Healthiest Nuts By Nutrients

Nuts are nutrient-dense, meaning they have a lot of nutritional value for their calories. They contain many minerals and vitamins, from Vitamin A to Zinc, and they’re low in saturated fats. In addition, the healthiest nuts have fiber, a dietary necessity that helps the digestive system function properly. Nutrient-wise, the top five nuts are pistachio, ginkgo nut, hazelnut, almond, and chestnut. These nuts have healthy unsaturated fats, carotenoids and a high ratio of nutrients to calories.

High Protein Nuts

Protein is vital for a healthy diet, serving as a building block for muscles, bones, and skin. It also helps the body manufacture hormones and enzymes. Nuts are one of the only non-meat sources of protein and are popular among vegetarians and those trying to cut down on their meat consumption. Almonds, pistachios, and cashews offer the highest amount of protein, averaging five to six grams per serving size. Walnuts and hazelnuts follow close behind, with three to four grams.

Best Nuts for Weight Loss

Most people don’t associate nuts with diet foods. However, studies have shown eating a handful of the right kind of nuts can help you stay full longer and boost metabolism, burning fat more quickly. Nuts have monounsaturated fats, which can reduce the desire to eat within three hours of a meal by 40% and also serve to reduce the amount of fat the body stores. Some nuts, like almonds, contain L-arginine, an amino acid that helps the body burn more fat and carbs during workouts. Other nuts great for weight loss include Brazil nuts, walnuts, pistachios, chestnuts and ginkgo nuts.

Heart Healthy Nuts

Even though they are often touted as high-fat foods, nuts have lots of  “healthy” fats and few saturated fats. In fact, walnuts contain a fatty acid known as alpha-linoleic acid that helps reduce plaque buildup in the arteries and can lower overall cholesterol levels, particularly LDL (the “bad” cholesterol). Eating certain nuts also lowers blood pressure. Heart-healthy nuts include pistachios, walnuts, almonds, and pecans.

Research into Cancer Benefits

For those diagnosed with colon cancer, nuts can be a true lifesaver. Research indicated cancer patients who ate at least two servings of nuts per week (1-ounce serving size) had 57% improvement in overall recovery rates. There is no proof currently that nuts can help prevent cancer; however, research is ongoing, and there is some evidence that eating nuts in adolescence can reduce a woman’s likelihood of developing breast cancer. Finally, walnuts and Brazil nuts are high in selenium. This trace element defends the body from free radical damage and is said to reduce the risk of cancer.

How Not to Eat Nuts

Nuts are usually a healthy addition to any diet. But if they’re not prepared thoughtfully, consumers can easily negate the nutritious benefits of the food. Nuts should not be roasted in hydrogenated oils or heated to temperatures high enough to destroy the cooking process. Also, avoid nuts that have been coated in syrup, sugar, or chocolate, since all this does is add extra calories. Also, it is easy to eat too many nuts. Remember, they still high-calorie foods and should be consumed sparingly.

Preparation of Nut Dishes

Some people have difficulty digesting raw nuts because of the phytic acid they contain. To maximize the nutrients contained in nuts, consumers should soak fresh nuts in salt water for 18-24 hours and then let them dry. They can be dried in the oven (on the lowest setting), in the sun, or in a dehydrator. Some nuts, like cashews, pine nuts, hazelnuts, and macadamias should only be soaked for six hours and immediately roasted. Once prepared, they can be eaten by the handful or ground and used in cooking or smoothies.

The Consequence of Nut Allergies

Nuts have extensive dietary benefits, but many people have nut allergies that make eating them impossible. Some allergic reactions are simply annoying: skin reactions, cramps, and digestive issues are common. Anaphylaxis is an extreme reaction that can cause death. Peanuts, technically legumes not nuts, are a common culprit of allergies, but walnuts, cashews, pistachios, and almonds can also lead to an allergic response. While there is no way to guess who might develop a nut allergy, at least one recent study has hinted that pregnant women who eat peanuts once a week or more during pregnancy reduce the risk that their child will be allergic to nuts.

Nuts: The Big Picture

It’s clear nuts have nutritional benefits far beyond their vitamin and mineral content. Choosing which nuts to consume on a regular basis becomes more about personal preference and availability than anything else. There are, however, nut varieties that seem to stand out. Overall, the five healthiest nuts appear to be walnuts, almonds, pistachios, Brazil nuts, and cashews. But really, all nuts have health benefits. Therefore, it isn’t so important what types of nuts you consume, but that you enjoy them in moderation.