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The Promise

Your brain already holds the tools you need to lose weight and keep it off. At least, that's the theory behind the Instinct Diet. You learn how your brain responds to eating and how various foods affect the brain. Then you use the information to shed pounds.

The Instinct Diet comes from creator Susan Roberts, PhD, a nutrition professor at Tufts University. She says you don't have to count calories, but you do have to base your eating around protein, certain carbohydrates, and fiber.

On average, people will lose an average of 30 pounds over about 6 months on the Instinct Diet, Roberts says.

What You Can Eat and What You Can't

The diet is divided into stages.

In the first stage, which lasts 2 weeks, you won't be able to eat refined carbohydrates like white bread or drink alcohol.

In the later stages, you can add "free choices" like steak fries (only six at a time) or one glass of alcohol a day.

Level of Effort: Medium

The diet is flexible and gives you lots of food choices.

Limitations: Once you finish the first stage, you'll be able to choose from a wide variety of foods, including treats such as chocolate.

Cooking and shopping: You can use the diet's shopping list at any grocery store. The book includes recipes and ideas for meals you can serve up from prepared food from the supermarket.

Packaged foods or meals: No.

In-person meetings: Not required, though the diet has in-person classes in the Boston area as well as online classes. You can also subscribe to a newsletter about the diet.

Exercise: Roberts says you can lose weight without exercising but recommends you do it anyway for your health.

Does It Allow for Dietary Restrictions or Preferences?

Vegetarians, vegans, and people on low-fat or low-salt diets should have no trouble following the Instinct Diet.

What Else You Should Know

Cost: Just your regular food shopping. Your first shopping trip will be the most expensive, because you'll probably buy a lot of new items. If you take a group class, those cost between $275 and $299.

Support: You can do this diet alone, or you can take a class or find support online with other dieters.

What Maryann Jacobsen, MS, RD, Says:

Does It Work?

Yes, it can help you lose weight. That's because the diet is based on eating mostly healthy, whole foods that fill you up on fewer calories. The foods also are low on the glycemic index, meaning they won’t raise your blood sugar too much.

Is It Good for Certain Conditions?

The diet isn’t extreme and promotes healthy eating principles, which can help you with conditions like high blood pressure and high cholesterol.

If you have diabetes, the plan's information on the glycemic index may be helpful.

The diet also recommends foods that are low in saturated fat and high in fiber, which are good for managing heart disease.

Ask your doctor if this plan is OK for you. And be sure to follow any guidelines that your doctor or dietitian gave you, such as limiting sodium if you have high blood pressure.

The Final Word

The Instinct Diet provides healthy eating advice and helps you understand why eating certain foods can control your appetite.

The downside is that it doesn't give specifics on exercise, and you might feel like you're eating the same foods over and over.

If you’re starting your first diet or don’t like to cook, then the requirements of this plan might be a challenge for you.

WebMD Diet A-Z

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