Dean Ornish Diet Review: Does It Work?

Medically Reviewed by Christine Mikstas, RD, LD on May 13, 2025
4 min read

Maybe you want to lose 15 pounds — or maybe 100. Maybe you've had a heart attack , and you're improving your diet. Or perhaps you've already lost weight and want to keep it off.

Forget all-or-nothing approaches, Dean Ornish, MD, says. His latest diet plan, called the Spectrum diet, is not about banning foods.

He ranks foods from the healthiest ("Group 1") to the most indulgent ("Group 5"). In general, the more you stick with foods toward the Group 1 end of the spectrum, the more benefits you'll get in terms of weight loss and overall health.

Besides food, Ornish also emphasizes thinking about how active you are, how you respond to stress, and how much love and support you have in your life.

Nothing is entirely off-limits, but how much you can eat of some foods (including poultry, refined carbs, sugar, and alcohol) depends on your goal.

Try to fill most of your plate with the following foods:

  • Fruits and vegetables
  • Egg whites
  • Green tea
  • Tofu and other soy-based foods
  • Legumes, such as lentils and beans
  • Whole grains
  • Nonfat sweets

Enjoy these foods sparingly:

  • Oils and fats
  • Meat, poultry, and seafood
  • Nuts and seeds
  • Egg yolks
  • High fat foods such as coconut, avocado, and olives
  • Full-fat dairy products such as yogurt, cheese, and milk
  • Caffeine (except from green tea)

It's up to you how far you want to take the program. You could go for a major change, or a more moderate one, depending upon your goals.

Limitations. Meat lovers and people who eat a lot of highly processed foods may find it hard to adapt to this plan. If you have a condition such as heart disease, you'll have more limitations, including how much fat is in your diet.

Cooking and shopping. Ornish encourages choosing fresh, seasonal foods — organic, when possible. The Spectrum includes many healthy recipes (by chef Art Smith) that are easy to follow.

Packaged food or meals. None.

In-person meetings. No, but you can participate in a nine-week online program offered through the program's website that includes live classes on managing your diet and exercise goals.

Exercise.Ornish recommends getting regular, moderate exercise, such as 20-30 minutes of walking every day. He also encourages people to manage their stress by practicing yoga, meditating, and using other relaxation techniques.

Yes. For example, it's easy to eat a vegetarian, vegan, or low-fat diet on this plan.

The plan isn't gluten-free, so if you're avoiding gluten, you would need to look for gluten-free foods.

Cost. Most of the healthiest foods recommended are not expensive, though some, such as fish, can be costly.

Support. "Ornish Living" is an online resource with content about nutrition, fitness, stress management, and love and support.

Does the Ornish diet work?

Yes, the Ornish Spectrum diet works. It works for anyone, but it targets those with or at risk of heart disease.

This program includes a stepwise approach to nutrition that starts as a very-low-fat diet. Historically, this type of low-fat, high-carb diet was proposed for people with heart disease.

The diet starts with complex carbs, fruits, and veggies. That makes it high in fiber and low in calories. Yet, the stages of the diet could be considered restrictive.

Like any diet that changes how you eat, you'll have to do lots of planning, and you may need nutritional guidance when you're getting started.

Is it good for certain conditions?

The Spectrum program works especially well for people who want to lower their risk of heart disease. Some experts warn that the low-fat, high-carb approach may increase the triglycerides in your blood, but years of research back the diet and the program. The resulting weight loss will reduce triglycerides, blood sugars, and blood pressure.

The Spectrum includes examples of how to use the program to lose weight, lower cholesterol, lower blood pressure, and help prevent or treat diabetes, heart disease, and other conditions.

The final word

Any successful weight loss program needs to address what works for you. Restricted diets require time, planning, and nutritional knowledge. For instance, restricting fat can limit some foods that have calcium, vitamin B, and zinc, and your body needs some fat to absorb certain vitamins.

So the diet in Ornish's Spectrum program is ideal for the detailed-oriented and committed person. If you aren't used to cooking and shopping, this program may not be a match for you unless you're ready for a big change.

Is the Dean Ornish diet vegetarian?

No. You can still eat meat on the Ornish diet, but try to limit it.

What are the negatives of the Ornish diet?

If you are not used to planning out your meals or rely mostly on prepackaged foods for most of your meals, this diet plan may be a big adjustment. While you can technically eat any food in moderation, if you're trying to stick to just the recommended foods for the Ornish diet, you may feel restricted when you go out to eat or when you're trying to get enough protein. Over time, this may make the diet plan difficult to sustain.