Table of Contents
The Rosedale diet is a diet that was created by Dr. Ron Rosedale. It limits carbohydrates and proteins and is supposed to be able to help the body stabilize levels of leptin, a hormone believed to trigger the brain to send hunger signals to the body.
Ron Rosedale, M.D. practices nutritional and metabolic medicine in Denver, Colorado. Metabolic medicine is generally considered an alternative medicine. Practitioners of metabolic medicine believe that a person’s metabolic activity can be altered through diet, stress reduction, and other changes that do not have to include prescription drugs. It is believed that diseases and conditions can be resolved through these types of metabolic changes, and by bringing the metabolic activity of the patient back into a fully functioning state. It is this idea of changing metabolic activity that underlies the Rosedale diet.
Dr. Rosedale attended the Northwestern University School of Medicine, and graduated in 1977. He is the founder of the Rosedale Center in Denver, Colorado, as well as the Carolina Center of Metabolic Medicine in Ashville, North Carolina. He also co-founded of the Colorado Center for Metabolic Medicine in Boulder, Colorado. His book The Rosedale Diet was written with Carol Colman who has co-authored many diet and fitness books. The book first appeared in 2004.
For many years, doctors, researchers, and many others have been trying to decode all of the ways that the body gets signals about food and hunger, and how the body knows when and how much to eat. The process of eating and breaking down food is extremely complex and involves many different glands, hormones, organs, and other body parts. People have been studying leptin for more than a decade to try to determine what role it plays in the body's hunger, eating, and digestion processes. Dr. Rosedale came to the conclusion that leptin problems are responsible for many of the issues that cause people to gain and retain fat. Dr. Rosedale used this information about leptin and his background in metabolic medicine to develop a set of guidelines, called the Rosedale diet, which he believes will help dieters restore the proper functioning of leptin and their metabolic systems and allow them to lose fat and become more healthy.
The Rosedale diet is based around the belief that leptin signals the body when to be hungry, when to be full, when to make fat, and when to burn fat. Leptin is a hormone secreted by fat. High leptin levels should tell the brain that there is plenty of stored fat, and that the body doesn't need to store any more. Some stored fat is important, because the body wants to make sure that if food becomes scarce, the body has a back-up store of energy so that it can survive until food becomes more plentiful.
Dr. Rosedale believes that many people with weight problems have become leptin resistant. This means that although their fat continues to produce leptin at normal levels, the brain cannot “hear” those signals correctly any more. Dr. Rosedale compares it to being in an room that smells bad for a long time, and no longer noticing the smell. When a person has a lot of stored fat the leptin signals going to the brain may eventually cause the same kind of phenomenon, beginning a vicious cycle of increased weight gain and increased leptin levels. Because the brain does not hear the leptin correctly, the brain thinks that the body has low levels of leptin. This signals the brain that the body needs to eat more and store more fat. Therefore, a person gets hungry and the body converts much of the food that gets eaten into fat.
The Rosedale diet is designed to get the body's leptin levels back into balance, and allow the brain to know that there is excess fat stored on the body. According to Dr. Rosedale, this will tell the brain to send signals to the dieter that he or she is satiated and not hungry, even if he or she has not eaten recently. Then the body will burn the fat stores, and weight loss will occur. Rosedale claims that this weight loss can occur without the muscle mass loss usually associated with weight loss, if leptin levels are balanced correctly.
The diet begins with a three week period of severe restriction. The only foods allowed during this periodcome from Dr. Rosedale's set of “A list” foods. During this period almost no carbohydrates are consumed, and protein consumption is limited. Saturated fats are restricted, but unsaturated fats are encouraged. Some of the foods suggested during this part of the diet include goat cheese, crab, lobster and other seafoods, olives, avocados, and many types of nuts.
Foods from the “B list” of foods are reintroduced after the initial phase of the diet. Some of the foods eventually allowed include fruit, lamb chops, steak, and beans. The second phase of the diet is intended to be followed for a lifetime to help maintain the body's leptin levels.
Dr. Rosedale suggests that dieters exercise for 15 minutes each day while on this diet. He also makes many recommendations for supplements that he suggests will help dieters lose weight and be more healthy while dieting. At one time, many of these recommended supplements were available from his company Rosedale Metabolics.
The Rosedale diet claims to be able help dieters lose fat mass without losing muscle mass. It is intended to be a lifestyle changing diet that continues after the initial three weeks are over as a changed set of eating habits that continue for a lifetime. It is intended to provide overall better health and well being.
There are many benefits associated with weight loss when the weight loss occurs at a moderate pace through healthy eating and regular exercise. There are many diseases and conditions for which obesity is considered a significant risk factor. These include diabetes and cardiovascular disease. People who are the more obese are generally at a higher risk and have more severe symptoms. Losing weight can reduce the severity of symptoms that occur with obesity-related disorders, and in some cases can even help the symptoms resolve completely. Dr. Rosedale believes that his diet can have these positive effects for patients with heart disease, diabetes, hypertension, and other diseases and conditions.
Anyone who is thinking about beginning a new diet should consult their physician or another medical practitioner. A physician can help the dieter determine if the diet in question is the right diet to meet their personal health and fitness goals. Requirements of calories, vitamins, and minerals can be very different for different people, and can vary based on age, gender, weight, activity level, the presence of diseases or conditions, and many other factors. A dieter’s physician can help the dieter determine what his or her personal needs are for maintaining good health. This diet limits protein, so it is possible that some people, especially those who are very athletic, or those who are strength training, may not get enough protein for good health. Women who are pregnant or breastfeeding should be especially cautious. When babies are receiving all of their nutrients from their mother, what the mother eats can have a significant impact on the baby's health ! and well-being.
The various merits and risks of a high fat diet, even when the diet is only high in “good” fats are hotly debated. Anyone thinking of beginning this diet who has cardiovascular or any disease for which a high fat diet is considered a risk factor should exercise extreme caution. Before any kind of dietary change is made, especially one that could cause a condition to worsen, a personal physician and any other doctor supervising care (such as a cardiologist) should be consulted and the possible costs and benefits of such a diet should be weighed carefully.
There are some risks with any diet. Any diet that significantly limits certain types of food may make it
hard for a dieter to get enough of all the necessary vitamins and minerals needed for good health. Although this diet recommends a number of vitamins and supplements, a dieter should consult his or her own physician before starting any kind of supplement. Supplements and multivitamins can help reduce the risk of a deficiency occurring during a restricted diet, but taking a supplement or vitamin has its own risks that should be carefully considered.
There has been no significant scientific research on the effectiveness of the Rosedale diet at helping people lose weight or burn fat. It also has not been scientifically shown to allow the body to burn fat without burning any muscle mass. It has not been evaluated to determine its effectiveness at improving the symptoms of or treating any diseases or conditions including type II diabetes, heart disease or hypertension. Studies have shown however that these and other obesity-related diseases and conditions can be improved through weight loss. The Rosedale diet also has not been clinically proven to help people live longer.
Leptin has been studied by many different researchers, but like many things that are engaged in more than one aspect of various reactions within the body, it is not always easy for scientists to come to a definite conclusion. Many of the studies done have been on animals, although some studies have been done on humans as well. It is more difficult for researchers to study reactions in humans because it would be unethical to do something in an experiment that was expected to cause a negative outcome in a person. Because of this, studies of humans often have to rely on evidence that cannot be as carefully controlled as when animal subject are used.
Although not everything is known about the way the leptin acts on the various organs of the body, scientists have linked it to obesity in both mice and humans. Injections of leptin were found to have significant effects on the body weight of mice. Mice with mutated genes that made their body unable to react to leptin were found to have a body mass three times greater than mice that had a normal gene. It is possible that some humans have a similar mutated gene, but evidence suggests that it is more likely that most leptin problems in humans stem from a decreased sensitivity to leptin due to the overproduction over time of the hormone. The presence of high leptin levels has been shown to correlate with obesity and weight gain in humans. In a March 2007 study published in the Journal of Clinical Endocrinology and Metabolism, Abby F. Flesch et al. presented research showing that children with high levels of leptin in the blood were more likely to gain body fat during the follow-up period than children with low leptin levels.
The Rosedale diet suggests that dieters severely restrict carbohydrates in the diet, and eat a large quantity of “good” fats. Although unsaturated fats, like those found in olive oil and many nuts, have been found to be more healthy than saturated fats, such as the fat found in butter and fatty meats, it is not clear that unsaturated fats are good for the body in large quantities. Although some fat is necessary for a healthy diet, most experts recommended a diet low in all types of fats, with unsaturated fats preferable to saturated and trans fats.
The United States Department of Agriculture makes recommendations for the number of servings from each food group that should be eaten each day to get a balanced, healthy diet in its MyPyramid food guide. MyPyramid recommends the equivalent of 3 to 4 ounces of grains each day for healthy adults, of which at least half should be whole grains. Because the Rosedale diet limits carbohydrates so severely, dieters may not eat enough bread and grains to meet this recommendation.
In 2007, the Centers for Disease Control recommended that adults get 30 minutes or more of light to moderate exercise each day for good health. The recommendations that Dr. Rosedale makes for dieters following his diet plan is less than this minimum recommendation. Dieters may wish to consider doing exercise above and beyond the amount recommended by Dr. Rosedale.
Castracane, Daniel V. and Michael C. Henson, eds. Leptin. New York: Springer, 2006.
Rosedale, Ron and Carol Colman. The Rosedale Diet. New York: HarperResource, 2004.
Shannon, Joyce Brennfleck ed. Diet and Nutrition Sourcebook. Detriot, MI: Omnigraphics, 2006.
Willis, Alicia P. ed. Diet Therapy Research Trends. New York: Nova Science, 2007.
American Dietetic Association. 120 South Riverside Plaza, Suite 2000, Chicago, Illinois 60606-6995. Telephone: (800) 877-1600. Website: <http://www.eatright.org>
Get the Skinny on Diets 2007. <http://www.skinnyondiets.com> (March 26, 2007).
Helen M. Davidson