When you think 'green' in March, maybe you think of leprechauns or four-leaf clovers. Or maybe you think about Al Gore and hybrid vehicles clogging up the HOV lanes during rush hour.

But let's not forget the original 'green' mindset, say nutrition, experts, and it involves diet.

Here’s a sampling of some green foods UT Southwestern dietitians recommend for March which, along with being a chance to drink green beer, is also National Nutrition Month (no, the green beer does not count as nutrition):

• Avocado – Also known as an alligator pear, the avocado is a good source of monounsaturated fats, which help lower cholesterol, said Dr. Vickie Vaclavik, clinical assistant professor of clinical nutrition at UT Southwestern. Avocados also are good sources of both vitamin E and lutein, a natural antioxidant that may help maintain eye health.

• Broccolini – A cross between broccoli and Chinese kale, broccolini is sometimes sold under the name asparation. It’s packed with the cancer-fighting nutrients isothiocyanates, sulforaphane and indoles – all linked with reducing the risk of breast, prostate, cervical, lung and other cancers – and offers as much vitamin C as orange juice, said Dr. Jo Ann Carson, professor of clinical nutrition at UT Southwestern.

• Brussels sprouts – Part of the cabbage family, brussels sprouts are another cruciferous vegetable with cancer-fighting phytochemicals. “They’re also high in vitamin C and are a good source of folate, vitamin A and potassium,” said Lona Sandon, assistant professor of clinical nutrition at UT Southwestern and a spokesperson for the American Dietetic Association. “Look for small, compact, bright green sprouts for the best flavor.” Ms. Sandon said the vegetable can be boiled, braised, steamed or microwaved. Just avoid overcooking, as they get mushy.

• Kale – A good source of vitamins K, C and beta carotene, kale is a form of cabbage in which the central leaves don’t form a head. A half-cup of cooked kale packs 1.3 grams of fiber but just 20 calories, said Cindy Cunningham, assistant professor of clinical nutrition at UT Southwestern.

• Nopales – Popular in the Mexican diet, nopales – also known as nopalitos or cactus pads – offer numerous nutritious advantages and are a great option for those managing diabetes or high blood pressure. “Not only is it low in calories at 22 calories per cup, the vegetable is also low in sodium and high in fiber,” Dr. Carson said. “In addition, a cup contains more calcium that an ounce of cheese and about half the potassium of a banana.”

• Okra – This staple of Southern cuisine is naturally low in calories and a good source of soluble fiber. It also provides some vitamin A. “It can be cooked whole until tender, then marinate it for about three hours in a small amount of vinegar in the refrigerator,” said Joyce Barnett, clinical assistant professor of clinical nutrition at UT Southwestern. “Top the drained okra with chopped onions and tomatoes for an out-of-the-ordinary salad.”

• Tomatillo – A common ingredient in Southwestern or Mexican cooking, the tomatillo looks like an unripe tomato covered in a paper-like leaf. The vegetable, which is a good source of vitamin C and potassium, is used in salsa verde and can be eaten raw. “But cooking brings out its flavor,” Ms. Sandon said.