What Is the Ornish Diet?

Ornish diet

Verywell / Debbie Burkhoff

At Verywell, we believe there is no one-size-fits-all approach to a healthy lifestyle. Successful eating plans need to be individualized and take the whole person into consideration. Prior to starting a new diet plan, consult with your healthcare provider or a registered dietitian, especially if you have an underlying health condition.

What Is the Ornish Diet?

The Ornish diet, conceived by Dean Ornish, MD, is designed to be a heart-healthy eating plan. It restricts dietary fat quite severely (to less than 10% of daily calories) and requires that all fats come from plant sources. The goal of the diet is not necessarily weight loss; it is to prevent coronary artery disease progression (CAD) and improve coronary artery plaques.

However, clinical studies in which dietary fat was restricted to less than 25% of daily calories have failed to demonstrate a cardiovascular benefit. The American Heart Association once recommended a low-fat diet, but has since changed its guidelines.

The 2021 U.S. News and World Report Best Diets ranks the Ornish diet number 9 in Best Diets Overall and gives it an overall score of 3.6/5.

What Experts Say

"The Ornish diet is a very low-fat meal plan designed to promote cardiovascular health. Though there has been some controversy, this diet has proved successful for heart health in several scientific studies. Experts acknowledge it may be difficult for people to adhere to, though."
Chrissy Carroll, RD, MPH

The 7-Day Diet Plan

 While there are many different versions of the diet, here is one example of the "reversal" program. This is the more restrictive initial phase of the diet.

  • Day 1: Low-fat bran muffin, non-fat yogurt, berries; black bean burger, sweet potato, green beans; homemade yogurt ranch dip, vegetable sticks; mixed greens salad, roasted vegetables, mushroom soup, non-fat chocolate pudding cup
  • Day 2: Steel-cut oats, berries, non-fat milk; chickpea and vegetable salad; dried fruit, small handful almonds; baked tofu, green beans, rice, salad with vinaigrette
  • Day 3: Egg whites, zucchini, whole-grain toast, berries; tofu vegetable broth soup with whole-grain pasta shells; oatmeal, non-fat milk, apple; lentil chili, beet and carrot salad, whole-grain roll
  • Day 4: Green smoothie with cucumber, orange, mint, non-fat yogurt; smashed chickpea salad sandwich, mixed greens salad; hummus, carrot sticks, whole-grain pita; lentil soup, green beans, soy yogurt with strawberries
  • Day 5: Oat flour pancake, mixed berries; miso soup with tofu, veggie sticks; whole-grain crackers, green pea guacamole; cannellini beans, broccoli, brown rice, bowl of yogurt and chopped apple with cinnamon
  • Day 6: Low-fat apple spice muffin, non-fat yogurt, berries; tomato soup, mixed greens salad, whole-grain roll; mixed berry smoothie with non-fat milk; whole-grain pasta, roasted vegetables, tofu, marinara sauce
  • Day 7: Egg whites mixed into steel-cut oats, berries; lentil chili, low-fat whole-grain cornbread, mixed green salad; kale chips, hummus; black bean noodles in marinara and roasted vegetable sauce, baked apple with non-fat yogurt.


What You Can Eat

The Ornish diet is a very low-fat, vegetarian eating plan. Actually, it is a spectrum: On one end is the "reversal" program, used to reverse heart disease. A less restrictive version is the "prevention" program.

The reversal program is very low-fat and completely vegetarian, while the prevention program is a more flexible option that incorporates animal-based lean protein (such as fish and chicken), along with healthy fats from avocados, nuts, and seeds.

Fruits and Vegetables

This diet is mostly vegetarian, so prepare for plenty of produce. In addition to those fruits and veggies, you will use vegetarian sources of fats, such as olive oil, for cooking. Some examples include:

  • Carrots
  • Broccoli
  • Green beans
  • Asparagus
  • Cucumber
  • Apples
  • Grapes
  • Bananas
  • Melons
  • Berries

Whole Grains

You must swap refined carbohydrates for whole-grain versions on this diet.

  • Whole wheat bread products
  • Brown rice
  • Oatmeal
  • Amaranth
  • Quinoa

Legumes, Seeds, and Nuts

Legumes are a good source of protein in a plant-based diet. Nuts and seeds are higher in fat, so they are available on the prevention plan. Some examples include:

  • Chickpeas
  • Adzuki beans
  • Black beans
  • Lentils
  • Pumpkin seeds
  • Walnuts
  • Almonds

Fish

On the prevention plan, some fish is included, since it is a good source of omega-3 fatty acids.

  • Halibut
  • Cod
  • Tilapia
  • Sole

Eggs and Dairy Products

  • Egg whites
  • Small amounts of nonfat milk or yogurt

What You Cannot Eat

Fat is tightly controlled, so certain foods are eliminated on the Ornish diet.

Animal Protein

On the reversal Ornish diet, no animal proteins are allowed since they contain saturated fats.

  • Chicken
  • Beef
  • Pork
  • Egg yolks
  • Full-fat dairy

Fatty and Processed Foods

  • Fried foods
  • Breaded foods
  • Processed meat products

How to Prepare the Ornish Diet & Tips

Dr. Ornish has written several how-to books to fully describe his recommendations, along with cookbooks to help those on his diet learn a new way to cook. As long as you stick to the approved legumes, grains, fruits, and vegetables and limit your fat, you can eat until you are satisfied and there are no calorie limits. Dairy products that are low in fat can be eaten in moderation.

Stock up on the approved foods so that you always have them available. Switch your refined grain products for whole-grain versions so you have familiar foods on hand that are still Ornish diet-friendly.

The Ornish diet also encompasses lifestyle changes, including exercise, stress management (through breathing, meditation, and/or yoga), relationships (spending time with, and getting support from, loved ones), and smoking cessation if you are a smoker.

Sample Shopping List

The approved foods on the Ornish diet should be easily available in large grocery stores. If you'd like a lot of variety in your grains, nuts, and seeds, you may want to visit a health food store that has these foods in stock. Keep in mind that this is not a definitive shopping list, and if following the diet, you may find other foods that work better for you.

  • Fruits (apples, berries, oranges, grapes)
  • Vegetables (kale, carrots, potatoes, broccoli)
  • Whole grains (brown rice, oatmeal, whole-grain bread)
  • Grain-like foods (quinoa, buckwheat, barley)
  • Beans and legumes (chickpeas, black beans, kidney beans)
  • Nuts and seeds (walnuts, almonds, cashews)
  • Egg whites
  • Nonfat milk and yogurt
  • Green tea
  • Olive oil

Sample Meal Plan

The Ornish diet does not require you to count calories, eat on a particular schedule, or combine foods in a certain way. As long as you eat the approved foods, you can eat as much as you wish, whenever you wish. Keep in mind that this is not an all-inclusive meal plan and if following the diet, you may find other meals that work best for you. Here is an example of meals you may find on the prevention program.

Day 1

  • Breakfast: Egg white and vegetable frittata; roasted potatoes; strawberries
  • Snack: Nonfat Greek yogurt; peaches; low-fat granola
  • Lunch: Lentil chili; green salad with balsamic vinegar and olive oil
  • Snack: Raw vegetables; hummus
  • Dinner: Green salad with olive oil and vinegar; spinach and mushroom lasagna made with whole wheat noodles; roasted asparagus

Day 2

  • Breakfast: Egg white vegetable scramble; whole-grain bread; mixed berries; nonfat milk
  • Snack: Guacamole; whole-grain pita bread; grapes
  • Lunch: Tomato soup; black bean veggie burger patty; sweet potato wedges
  • Snack: Pesto dip with vegetables
  • Dinner: Arugula beet salad; poached cod; steamed vegetables with olive oil

Day 3

  • Breakfast: Apple spice oatmeal muffin; nonfat Greek yogurt; blueberries
  • Snack: Green smoothie
  • Lunch: Bean and chicken tacos; coleslaw; chipotle sauce; edamame guacamole
  • Snack: Fruit parfait with nonfat yogurt
  • Dinner: Salad with miso dressing; Thai vegetable curry; brown rice; pineapple

Pros of the Ornish Diet

Although the Ornish diet may not have as large of an effect on cardiovascular health as originally believed, it does introduce some dietary changes that may improve overall health.

  • Safety: There are no special health risks associated with the Ornish diet, as long as basic nutritional needs (for protein, carbohydrates, and nutrients) are met. However, its health claims may not be completely supported by scientific evidence.
  • Satiety: Although the Ornish diet limits the types of consumed foods, it does not limit the amounts. Eating plenty of fruits, vegetables, and whole grains can usually satisfy hunger.
  • Accessibility: No specialty foods are required on this diet, and the compliant foods are readily available. Sometimes they can be more expensive (e.g., quinoa pasta vs. traditional versions), but you also save money by cutting out meat. Also, there is no calorie-counting or food tracking, which may be appealing to some users.
  • Provides micronutrients and fiber: With the Ornish diet, you will consume plenty of fruits, vegetables legumes, and whole grains. These are nutritious foods that many people struggle to get enough of. Eating a variety of these foods makes your diet high in fiber and rich in vitamins, minerals, and antioxidants; all of these can play a role in helping support health and prevent chronic diseases.
  • Limits fat: Although it may not be necessary to completely eliminate saturated fats from the diet, as Ornish suggests, health experts agree that limiting these fats may improve heart health. The American Heart Association recommends consuming no more than 5% to 6% of daily calories from saturated fat (which means about 13 grams a day, if you consume 2,000 calories).
  • Limits sugar: Similarly, consumption of sugar, especially added sugar (vs. the sugars that naturally occur in many foods) is also associated with adverse health outcomes. This diet will reduce followers' sugar intake, which may be beneficial to their health.

Cons of the Ornish Diet

Despite its medical pedigree, the Ornish diet may not be appropriate for everyone and does include some risks. If you plan to make a significant change to your eating patterns, like the one represented by the Ornish diet, discuss it with your healthcare provider first.

  • Restrictiveness: Following a low-fat, vegetarian diet can be challenging, especially for people used to a typical American diet that emphasizes animal-based proteins and higher-fat foods.
  • Sustainability: With the restriction on fats, refined carbs, alcohol, and caffeine, some people may find it difficult to follow this diet for the long term. It is meant to be a lifelong change, not a temporary one, which is a big adjustment.
  • Time commitment: Eating vegetarian can take a lot of prep and cooking time. You also may need to learn how to cook differently, without meat and saturated fats. Also, most convenience foods and meals are off-limits on this diet.
  • Macronutrient imbalance: Cutting fat down to 10% of daily intake is challenging for most people. This may lead to a higher carbohydrate intake, which may not benefit someone who has pre-diabetes or diabetes. As well, this minimal fat intake may make it difficult to absorb fat-soluble vitamins.
  • Micronutrient deficiency: Plant-based foods contain many valuable micronutrients, but they don't typically offer much calcium, iron, or vitamin B12. Supplements may be required to meet the body's needs for these vitamins and minerals.

Is the Ornish Diet a Healthy Choice for You?

The Ornish diet shares many characteristics with other low- or no-meat and "heart-healthy" diets. It also generally meets US Department of Agriculture (USDA) recommendations on nutritional balance, with some planning and effort.

Although the USDA MyPlate guidelines include meat as a source of protein, the Ornish diet can meet these recommendations based on its emphasis on plant-based proteins (egg whites and nonfat dairy products also provide protein).

The USDA suggests roughly 2000 calories per day for weight maintenance, although this number can vary significantly based on age, sex, current weight, and activity level. The Ornish diet is based on reducing fat, not calories, so calorie intake will be different for everyone following the diet.

The Ornish Diet fits into the USDA's recommendations using mainly plant-based proteins. This may require careful planning to obtain enough high-quality protein as well as calories due to the low fat content.

A Word From Verywell

Based on the results of the Ornish study—the small randomized trial upon which all the famous claims regarding the Ornish diet are based—the notion that an ultra-low fat vegetarian diet improves heart health should be regarded as an intriguing hypothesis. Still, for weight loss, this diet holds promise and experts say that it is generally safe (although potentially difficult) to follow.

Remember, following a long-term or short-term diet may not be necessary for you and many diets out there simply don’t work, especially long-term. While we do not endorse fad diet trends or unsustainable weight loss methods, we present the facts so you can make an informed decision that works best for your nutritional needs, genetic blueprint, budget, and goals.

If your goal is weight loss, remember that losing weight isn’t necessarily the same as being your healthiest self, and there are many other ways to pursue health. Exercise, sleep, and other lifestyle factors also play a major role in your overall health. The best diet is always the one that is balanced and fits your lifestyle.

7 Sources
Verywell Fit uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
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By Richard Fogoros, MD
Richard N. Fogoros, MD, is a retired professor of medicine and board-certified in internal medicine, clinical cardiology, and clinical electrophysiology. He co-invented 19 awarded U.S. patents relating to the detection of cardiovascular disease, and is the author of numerous scientific articles, book chapters, and books.