Definition :
Dean Ornish’s Eat More, Weigh Less diet focuses on eating a diet of plant products low in fat, oils, and simple carbohydrates to achieve weight loss and better health without feelings of deprivation and hunger. It also emphasizes stress reduction techniques and light exercise. Dean Ornish, M.D. not only recommends this style of diet for weight loss, but also believes it can prevent and even reverse some forms of heart disease.
Origins :
Dean Ornish is a professor of clinical medicine at the University of California, San Francisco, and a practicing physician. He received his Bachelor of Arts degree from the University of Texas, Austin, then
attended Baylor College of Medicine and Harvard Medical School. He received further medical training at Massachusetts General Hospital. He is the founder and president of the Preventive Medicine Research Institute located in Sausalito, California.
While Dr. Ornish was a medical student he became interested in heart disease. In 1978 he began doing research on patients with coronary artery disease (a common form of heart disease). He created a diet that was very low in fat and completely vegetarian and studied its effects on the symptoms experienced by these patients. The patients also learned a variety of stress reduction techniques. He discovered that for many patients this diet caused a significant lessening of their symptoms. This was the beginning of Dr. Ornish’s research on the effects of low fat, low or no-meat diets on weight loss, health, and heart disease. This original diet is the basis for his Eat More, Weigh Less diet, as well as his other related diets.
Over the years, Dr. Ornish has published many different books and articles, and has recommended diets with many different names. All his diets revolve around the same basic principles, with additions or changes in emphasis, based on the goal that the diet is intended to achieve. For example, Dr. Ornish’s heart disease prevention diet allows small amounts of lean meat or fish, while his heart disease reversal diet is completely vegetarian.
Description :
Dr. Ornish presents his Eat More, Weigh Less diet as more of a spectrum of choices than a set of hard and fast rules. He believes that because people have many different goals, from moderate weight loss to actual heart disease reversal, no one set of dietary rules will fit everyone. He also emphasizes overall lifestyle change, not just through what a person eats but also through stress reduction, moderate exercise, and if applicable, quitting smoking.
The main component of the Dr. Ornish diet is eating more vegetable products and many fewer meat products. For people trying to lose moderate amounts of weight this may mean eating small amounts of lean chicken or fish as well as some skim milk or egg whites.
For those with more ambitious goals, the diet may be almost completely vegan (containing no meat or animal products at all).
The diet is also extremely low in fat, with fewer than 10% of calories coming from fat. The strictest forms of the diet do not allow any nuts, seeds, or avocados. The only oil Dr. Ornish allows is a small amount of fish oil each day because some research has shown it to be beneficial and may help prevent heart attack.
Foods that are encouraged include nearly all fruit and vegetable products. Especially recommended are
leafy greens, soy products, and whole grains. Whole grains contain many vitamins and minerals that are
removed when these grains are processed. Whole grains include things such as brown rice, oat bran, and wheat bran. They are broken down by the body more slowly than processed grains, meaning that energy is released more slowly and is available for a longer period of time.
A portion of food made up of processed foods and animal products usually contains many more calories
and fat than a similarly sized portion consisting mainly of vegetables, whole grains, fruits, and soy. This means that a person can eat a larger quantity of food while still consuming fewer calories and fat if the foods are chosen correctly. This is the key to the idea that on Dr. Ornish’s diet a person may be able to actually eat more and still lose weight. Eating more foods low in caloric density (calories per quantity) means the stomach is fuller and helps prevent feelings of hunger.
Dr. Ornish’s diet does not just focus on food. It also makes recommendations for other lifestyle changes. He recommends moderate exercise of 20 to 30 minutes daily of at least a moderate walking pace. Dr. Ornish also suggests making small changes throughout the day to get more exercise, such as parking a few spaces further from the door, or even just walking up or down the stairs instead of taking the elevator. This kind of daily exercise adds up and is recommended over working out strenuously only occasionally.
Stress-reduction techniques are an important part of the total lifestyle plan. Dr. Ornish contends that doing even a few minutes of yoga, deep breathing, or meditation each day can have many positive effects on both the body and mind. Dr. Ornish also highly recommends that individuals quit smoking.
Function :
Dr. Ornish’s diet can be used for weight loss, or for a variety of other healthy living goals including prevention or possible reversal of heart disease.
Benefits :
Because this diet includes almost only plant products, it is high in substances thought to promote health
such as antioxidants and fiber, as well as low in substances that are harmful to the health such as fat and
cholesterol. Following the diet’s recommendation of light exercise can also be very beneficial. Walking 20 or 30 minutes a day instead of being completely sedentary has significant health benefits and may even reduce the chance of early death by half.
Although Dr. Ornish’s diets are effective at causing weight loss and improved overall health, the most researched and discussed benefit of his diet program is the prevention and even reversal of heart disease. Dr. Ornish and colleagues have done extensive researchshowing that following a very strict, completely vegetarian form of his diet can not only prevent heart disease from occurring or getting more severe, but can actually cause a reversing of artery constriction allowing blood to flow to the heart better. Dr. Ornish also believes his diet may be effective at preventing or reversing other forms of disease such as prostate cancer.
Precautions :
Anyone thinking of beginning a new diet should consult their physician. Requirements of calories, fat, and nutrients can differ significantly from person to person, depending on gender, age, weight, and many other factors such as the presence of any diseases or conditions. Pregnant or breastfeeding women should be especially cautious because deficiencies of vitamins or minerals can have a significant negative impact on a baby.
Patients with heart disease should be especially careful when beginning a diet. Although Dr. Ornish has published data about how his diet may be able to prevent or reverse heart disease, everyone reacts differently and no major dietary changes should be made without consulting a physician. Dr. Ornish’s diet is not a replacement for cholesterol-lowering drugs or any other medications prescribed by a doctor, and is not a replacement for medically recommended procedures. It is important to discuss all possible options with a physician and make all decisions based on professional recommendations.
Risks :
Dr. Ornish’s diet is very low in fat and limits meat and animal product intake to little or none. Many important vitamins and minerals such as zinc and vitamin B12 are acquired from these sources in a normal diet. Without these sources there is a significant possibility of deficiency. Also, because of the very low fat allowance of the diet there is some concern that people on this diet may not get enough vitamin E, which is found mainly in nuts and oil. These are too high in fat to be eaten regularly while on this diet. Dr. Ornish often recommends taking supplements while following his diet, and taking a complete multi vitamin may help reduce the risk of a deficiency. Multivitamins and supplements however have their own risks, especially for pregnant or breastfeeding women and individuals with medical issues such as renal disease.
Research and general acceptance :
The benefits of any diet low in fat that includes many different fruits, vegetables, and whole grains are generally accepted. However, some concern has been expressed about Dr. Ornish’s Eat More, Weigh Less diet because of dietary deficiencies that may occur due to the restriction of so many food types. For some people this cause for concern may outweigh the possible benefits.
One benefit of the Dr. Ornish diet that he and other researchers have studied extensively is the possible prevention or reversal of heart disease in some people. Dr. Ornish has led many controlled research studies to test his diet, and published the results in peer-reviewed journals such as the Journal of the Society of Behavioral Medicine, the Lancet, and the Journal of the American Medical Association.
In 1990, Dr. Ornish and several coauthors published an article titled ‘‘Can Lifestyle Changes Reverse Coronary Heart Disease? The Lifestyle Heart Trial’’ in the Lancet. This was the first study to investigate
whether changes in lifestyle alone, without the use of prescription drugs, could stop the progress of, or even reverse, coronary heart disease. The patients selected to participate had severe coronary heart disease and were divided randomly into two groups, those who would follow Dr. Ornish’s program, and those who would follow the usual recommendations for such patients, including moderate lifestyle changes and cholesterol-lowering medications, if necessary.
Dr. Ornish’s regimen included a diet very low in fat and completely vegetarian. It also emphasized moderate exercise, stress-reduction techniques, and, for those patients who smoked, quitting. The diameter of the coronary artery was measured at the beginning of the study, and again at the end of the study one year later. For patients following the usual recommendations for coronary patients, the average percentage of narrowing was 42.7% at the beginning of the study and increased 3.4% to 46.1% at the end of the study. For patients who followed Dr. Ornish’s plan the average percentage of constriction was reduced 2.2% during the period of the study from 40.0% to 37.8%. For the patients with the most constriction the difference was even greater.
Since the original Lifestyle Heart Study, Dr. Ornish and various co-authors have continued to research how lifestyle changes alone can positively affect heart disease. He has also done research over longer periods of time to see if people are able to stay on his diet and continue to see positive effects. He has also studied very short time spans to see if improvement can occur very quickly. In 2007 he published a
study in the Journal of the Society of Behavioral Medicine showing that, in as little as three months, his lifestyle change program could significantly reduce the risk factors of coronary heart disease.
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