High in protein and "good" monounsaturated fat, walnuts add a satisfying crunch to many meals and snacks. Walnuts are not only rich in flavor, but they also offer valuable health benefits.

When substituted for saturated fat in the diet, walnuts can help lower total cholesterol as well as bad (LDL) cholesterol without affecting levels of good (HDL) cholesterol. Unlike other nuts, walnuts are high in alpha-linolenic acid (ALA), an omega-3 fat that has been shown to have antioxidant and anti-inflammatory properties and to help keep triglycerides, the bad fat associated with prediabetes, under control. Moreover, walnuts are recommended in moderation on every Phase of the South Beach Diet.

Types of Walnuts: While there are three varieties of walnuts, you're most likely to find English walnuts in your supermarket. Black walnuts are less common but can be found in specialty stores, while butternut, or white walnuts, are very hard to find in the marketplace.

Choosing Walnuts: When buying walnuts in the shell, look for those with undamaged shells. Shake the nuts if you can: If the nuts feel extra light or rattle when shaken, they may be dried out inside. If you’re buying shelled walnuts, look for a freshness date on the package. Only buy nuts in bulk if you know the store has a high turnover rate.

Storing Walnuts: Walnuts are perishable and will spoil over time — particularly if they're exposed to heat, humidity, and light. To prevent nuts from spoiling, keep them in a cool, dry place. Walnuts left in their shells will stay fresh for about six months. Eat shelled nuts within four months. If you want to keep your nuts for a longer period of time, store them in the freezer for up to one year.

Enjoying Walnuts: Add some chopped walnuts to salads and dips, or enjoy them whole as a satisfying and tasty snack. Also look for walnuts in whole-grain breads at the supermarket. You can choose walnuts on all Phases of the South Beach Diet, but try to stick to a daily allotment of 15 — eating more may undermine weight-loss efforts.

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