For good health, the U.S. Department of Agriculture recommends that you get 1 1/2 to 2 cups of green vegetables a week. When you consider what green vegetables to eat, you probably think spinach and broccoli. While these are certainly healthy choices, if you're looking for a green vegetable that really packs a nutritional wallop, add seaweed to your weekly greens.

Good Choice for the Calorie Conscious

Like most other green vegetables, seaweed is low in calories, ranging from 15 calories in 1 1/2 pieces of kombu to 40 calories in four sheets of nori. Most Americans get more calories than they need, according to the 2010 Dietary Guidelines for Americans, and this trend is contributing to the obesity epidemic. Loading your plate with low-calorie vegetables like seaweed might help reduce your overall calorie intake without leaving you feeling hungry.

Build Stronger Bones

Vitamins in Seaweed

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If you're looking for a nonmilk source of calcium, seaweed fits the bill. Alaria, which is an Atlantic seaweed related to the Japanese wakame, has the most calcium, meeting 14 percent of the daily value in a 1/2-cup serving. Arame and hijiki, which are both Japanese seaweeds, are also good sources of calcium, meeting 10 percent of your daily value in a 1/2-cup serving. Calcium is not only important for bone health but also muscle function, nerve transmission and hormone secretion.

Build Better Blood

Both alaria and dulse -- an Atlantic seaweed grown off the coast of Maine -- are good sources of both iron and vitamin B-12. You need both of these nutrients to make red blood cells. Not getting enough iron or vitamin B-12 in your diet can lead to anemia, which can make you feel tired, dizzy and irritable. For vegans, seaweed makes a good green vegetable choice because vitamin B-12 is primarily found in animal products 2.

Keeps the Metabolism Going

Carbs and Protein in Spinach

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Iodine is a trace mineral that assists in the conversion of food into energy in your cells while also supporting normal thyroid function. Most people meet their daily iodine needs with iodized salt, according to MedlinePlus. But seaweed, with all its nutritional benefits, may be a better source. Depending on the type of seaweed, one serving meets 98 percent to 3,266 percent of the daily value for iodine.