What You Need To Know About the Ornish Diet

Losing weight and keeping it off is no easy task. With so many diets and eating styles out there, it’s often difficult to know where to start. Your best first step is to look for a plan that fits your tastes and lifestyle.

“If you’re drawn to vegetarian eating and a holistic approach to health, the Ornish diet might be right for you,” says registered dietitian Julia Zumpano, RD, LD. “But like most eating plans, your success depends on whether you can stick to it.”

We talked with Zumpano about what the Ornish diet is, and some pros and cons so you can decide if it might be a good choice for you.

What is the Ornish diet?

The Ornish diet was created in the 1990s by Dean Ornish, MD, to help people reverse heart disease.

Its core features are that it’s very low in:

• Fat: Less than 10% of calories per day should come from fat.
• Cholesterol: Limit cholesterol to less than 10 milligrams per day.

Ornish diet food list

Like many plant-based eating patterns, the Ornish diet relies heavily on nonanimal sources of protein (mainly legumes) along with fruits, vegetables and whole grains to fuel your body. The food guidelines and restrictions on fat and cholesterol reflect this focus:

Foods to enjoy

• Fruits and vegetables.
• Whole grains.
• Green tea.
• Legumes.
• Nonfat dairy foods.
• Tofu and other soy products.
• Egg whites.
• Limited amounts of alcohol and nonfat sweets.

Foods to avoid

• Added oils and fats.
• Chocolate.
• Caffeine, except for green tea.
• Dairy foods containing any fat, including milk, yogurt, cheese and butter.
• Egg yolks.
• High-fat plant-based foods, such as avocados, olives and coconut.
• Meat and poultry.
• Nuts and seeds.
• Seafood, including fish and shellfish.

Can the Ornish diet help you lose weight?

Typically, weight-loss eating plans have a calorie restriction. That’s not the case with the Ornish plan. But most people consume fewer calories given the low-fat, high-fiber foods they’re eating.

So, will you lose weight on the Ornish diet?

Compared to other popular diets, studies show the Ornish plan is moderately effective for weight loss. U.S. News and World Report ranks it 13th among the best weight-loss diets of 2024.

While following the Ornish plan, some people reach a weight-loss plateau. That’s true of most weight-loss eating plans.

“If you stop losing weight, consider talking to a dietitian about how to better balance your caloric intake to support weight loss. Exercise is a key factor in preventing weight loss plateaus,” Zumpano advises.

Ornish diet pros

There can be some big advantages of the Ornish diet. But it’s not right for everyone.

Let’s look at some of the highlights.

Easy to follow

The foods allowed on the Ornish diet are easy to find. And because you’re not counting calories, you can eat until you feel full and even snack between meals.

Encourages other lifestyle changes

Food is just one aspect of the Ornish program. The full program includes other strategies to help you succeed, including a nine-week online class.

If you go all-in on Ornish, you’ll not only learn what to eat but also the importance of:

• Exercise, preferably 30 minutes per day.
• Social support to help you in your weight loss journey.
• Stress management activities, like meditation, yoga and breathwork.

Reduces heart disease risk

Dr. Ornish’s original research showed their diet could significantly improve coronary artery disease. Other benefits shown in the study include:

• Lower levels of LDL (“bad”) cholesterol.
• Fewer cardiac events, such as heart attacks and heart-related deaths.

“Today, the Ornish plan is ranked by U.S. News and World Report as the third best heart-healthy diet,” Zumpano points out. “This plan can help you take ownership of your heart health by controlling risk factors and lowering your risk for heart disease.”

May be covered by insurance

Some insurance companies cover the nine-week diet and lifestyle program, Zumpano shares.

For example, it’s a benefit under Medicare for people with certain heart conditions. Insurance companies may also provide coverage if you have Type 2 diabetes or other risk factors for chronic disease.

May provide other health benefits

When you eat healthy foods and lose weight, you’re likely to see other positive changes in your health. Some possible benefits of the Ornish diet include:

• Better brain health.
• Enhanced diabetes management.
• Improved gut health.
• Lower blood pressure.
• Reduced risk of some cancers.

Ornish diet cons

No diet is perfect, nor is it right for everyone.

So, before you go all-out Ornish, consider these possible downsides.

Limits what you can eat

If you prefer to eat some meat, including fish, you may find this plan too restrictive. Cutting all added fats and oils can also be challenging.

May lead to nutritional deficiencies

Because of the reduced fat intake on the Ornish diet, you might miss out on essential nutrients.

“The biggest deficiency is healthy fats, such as omega-3 fatty acids,” Zumpano notes.

To offset nutritional deficiencies, the Ornish plan recommends a daily multivitamin and cholesterol-free omega-3 fatty acid supplement.

Other supplements are optional on the plan, including:

• Folic acid.
• Vitamin E.
• Vitamin C.
• Selenium.

Always talk with a healthcare provider before taking any supplements. Some may interact with other medications you’re taking or have other unintended effects.

May cause digestive problems

Perhaps the most common side effect of the Ornish plan is the potential for digestive problems due to the high amount of fiber. Although your body should adjust, the initial increase in fiber may cause:

• Bloating.
• Constipation.
• Diarrhea.
• Gas.

May not be right for you

Zumpano recommends checking with your healthcare provider before trying the Ornish diet if you:

• Are pregnant or breastfeeding.
• Have disordered eating, malnutrition or underweight.
• Have kidney failure.

Ornish diet vs. Mediterranean diet

When it comes to weight loss and overall health, the Mediterranean diet is one of the best, Zumpano shares. It’s similar to the Ornish diet in that both center on fruits, vegetables, legumes and whole grains. Neither emphasizes counting or restricting calories.

But there are some key differences. For example, the Mediterranean diet allows you to eat some foods that aren’t included in the Ornish diet. That includes foods like:

• Healthy fats, such as extra virgin olive oil, seeds, nuts and avocados.
• Meat, mainly skinless poultry.
• Limited amounts of red meat.
• Egg yolks.
• Moderate-fat dairy products such as part-skim cheese, cottage cheese and yogurt.
• Seafood, including a recommended three servings of fish per week.

On the other hand, the Mediterranean diet doesn’t specifically include the lifestyle aspects of the Ornish program. Although exercise is encouraged and social support is foundational to Mediterranean cultures.

If you’re looking for the right diet for you to lose weight, the most important consideration should be whether you can follow it.

If you can, you’ll probably be successful. But keep in mind, there is no “one size fits all diet” when it comes to weight loss. Consider working with a registered dietitian to help you develop a personalized eating and lifestyle plan to meet your health goals.

And always consult a healthcare provider before overhauling your diet.