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The Promise

Could you slow down aging, get more energy, and lose weight, too -- without counting calories or sacrificing taste?

The O2 diet, by registered dietitian Keri Glassman, says you can.

Glassman’s 32-day plan centers on the ORAC (oxygen radical absorbance capacity) scale, which tells you how rich a food is in antioxidants. The higher the ORAC score, the better.

On this plan, you count ORAC points, not calories. You eat more of the ORAC scale’s top-rated foods, including leafy greens, artichokes, blueberries, salmon, herbs, and spices and less of the lowest, such as fried foods, baked goods, candy, and soda.

What You Can Eat and What You Can't

You eat three meals and at least one snack a day.

Off-limits: fried foods, baked goods, sugar- and fat-free processed foods, high-fat or processed meats, soda, artificial sweeteners, trans fats, and high-fructose corn syrup.

The first few weeks of the plan can be fairly intense, particularly the first few days.

Phase 1 (lasts 4 days): This phase is a "cleanse." You get a whopping 50,000 ORAC points per day on very few calories, and you drink water and green tea.

Phase 2: You get 30,000 ORAC points a day, control your portions, and eat lots of fresh fruits and veggies for 2 weeks.

Phase 3: You can add one indulgence per week, and you get more food options. This phase lasts for 2 weeks.

Phase 4 (ongoing): Stick with the Phase 3 guidelines, plus one more indulgence per week and one more high-ORAC fruit per day.

You can't have alcohol during Phases 1 and 2. You can drink, in moderation, in Phases 3 and 4, as one of your indulgences.

Level of Effort: Medium

You may have to make a big change in your food choices, depending on what you eat now. But this change is meant to last.

Limitations: You have more restrictions at the start of the plan, which gradually loosens up.

Cooking and shopping: You should be able to find many ORAC-rich foods at your grocery store. The book includes tips for eating out and choosing foods at convenience stores.

Packaged foods or meals: No.

In-person meetings: No.

Exercise: Every week, you should do 2.5 hours of moderate exercise.

Does It Allow for Dietary Restrictions or Preferences?

You can easily adjust this plan to fit vegetarian, vegan, and gluten-free needs.

What Else You Should Know

Cost: Just your groceries.

Support: You do this plan on your own. Glassman's web site includes an option to order meals.

WebMD Medical Reference

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