Sara Swift

VEGETARIAN DIETS


 

Introduction

 Modern Western society has placed an emphasis on "healthy living." A well-balanced diet, exercise and healthy lifestyle habits; such as not smoking, moderate alcohol use, and preventive health care, are all very important to physical well-being. In their quest for a longer life and increased happiness, Americans have made great strides towards an healthier lifestyle and, in particular, an improved diet. Many individuals have attempted to lower fat intake and decrease excess calorie consumption. In a growing number of more recent cases this includes following a vegetarian diet. Vegetarianism is on the rise and was officially supported by the American Dietetic Association in 1993:

"It is the position of The American Dietetic Association that vegetarian diets are healthful and nutritionally adequate when appropriately planned."http://www.fatfree.com/FAQ/ada-paper

 

What is a "Vegetarian Diet?"

 There are different types of vegetarian eating patterns, differing in the extent to which they exclude animal products. Vegans or total vegetarians only eat plant foods, which include legumes or dried beans and peas, grains, seeds and nuts. Lactovegetarians eat plant food and include cheese and other dairy products. Ovo-lactovegetarians also include eggs. Semivegetarians are the least exclusive because they do not eat red meat but include chicken, fish, dairy products and eggs with plant foods. This paper will focus primarily on those individuals who include some animal products in their diet. These three types of vegetarians must still plan their diets carefully to include the nutrients needed for survival: such as protein, iron, vitamin B12, vitamin D, calcium, and zinc.

http://www.amhrt.org/Heart_and_stroke_A_Z_Guide/vegdiet.html

 

Why be a "Vegetarian?"

 There are a number of reasons why an individual might choose to follow a vegetarian eating pattern. Most importantly, many people believe that there are health benefits associated with the exclusion of animal products from a diet. "The Vegetarian Page" claims that meat is very unhealthy. Cholesterol and fat aside, there seem to be antibiotics, bacteria & parasites, and chemical toxins that humans ingest each time they consume commercial meat products. These ingredients can be very detrimental to physical well-being and can produce problems related to such things as digestion and a lack of cancer fighting agents in the body. Additional beliefs associated with vegetarianism contribute to people's reason for adopting this lifestyle. The belief exists that eating animals is unethical. Animals such as calves, young chickens and pigs, are often raised in terrible conditions in order to produce the choicest pieces of meat. Others have claimed that our ecology suffers as a result of raising cattle and therefore, "our species is being inefficient in its use of resources." Land is being destroyed that can never be regained. In addition, meat is more expensive than vegetables and other plant products. It is "more perishable, takes longer to harvest, requires refrigeration, is transported over vast distances, uses more resources." Finally, it is simply a tradition in most Western countries to eat a diet consisting of meat products. Although these additional reasons add to certain individuals arguments for becoming a vegetarian, the primary motivation seems to lie in the health benefits associated with meat (&other animal product)-free diet.

 
 

Why is a "Vegetarian Diet" more healthy and what diet plans have made this claim?

Many different groups and individuals have proposed plans and made claims that attest to the benefits of a vegetarian lifestyle. Three different plans will be discussed.

 Dean Ornish, MD, president of the Preventive Medicine Research Institute in Sausalito, CA, devised The Life Choice Diet. This low-fat diet, with less than 10% calories from fat, focuses on beans & legumes, fruits, grains and vegetables. Nonfat dairy products and commercial products can be consumed in moderation while sugar, alcohol and fats are to be avoided. Ornish proposed a treatment that included this diet, in combination with exercise and other health enhancing habits. He claimed that his program could have a positive effect on the progression of coronary heart disease. These changes were supposed to lower cholesterol and the level of saturated fatty acid in the blood which would lead to less clogging/blocking of the arteries. Dr. Ornish reported in Lancet (1990) and the American Journal of Cardiology (1992) that in his one-year study, 28 patients following his treatment plan showed a "measurable reversal" of coronary heart disease. After four years 22 of the same patients showed improved blood flow to the heart and less arterial blockage, while the control group got worse. The American Heart Association seemed to support the effectiveness of this plan in Ornish's study. However, the low-fat vegetarian diet alone was clearly not completely responsible for the changes that occurred. The question was raised - "which part of the treatment - diet, exercise, group support, counseling, stress reduction, or smoking cessation - had the most impact?" The AHA also questioned whether or not individuals could adhere to such a rigorous treatment plan on a long term basis. This association wants to decrease the risk of heart disease in the population and therefore advocated this program to the extent that the vegetarian diet and the exercise were concerned.

http://www.amhrt.org/Heart_and_Stroke_A_Z_Guide/ornish.html

 

 The McDougall Program was devised by John McDougall, MD, and is based on "proper foods, moderate exercise, adequate sunshine, clean air and water, and surroundings comfortable to your psychological well-being." Like Ornish's "Life Choice Diet," this program includes many aspects of healthy living. However, according to McDougall, "diet is a primary causative factor in all of the following diseases. Not only that, but these diseases are controllable"(a list of 34 systemic conditions, bowel problems and cancers follows). This is a starch-based, vegetarian diet including predominantly beans, corn, pastas, potatoes and rice with the addition of fruits and vegetables. If an individual has been on the program for more than three years, a non-animal source of B-12 is recommended. McDougall assumes that by eliminating protein and increasing grains and starchy vegetables, people will eliminate fat from their diet. He loosely claims that "research" has revealed that the higher percentage of dietary fat, the greater the long-term health problems and the quicker the progression of disease. "High fat diets have also been implicated in various cancers, heart disease, and adult onset diabetes," he concludes. McDougall offers no evidence to back his claims other than mentioning that Asians live primarily on rice. Because starches are their staple foods, Asians tend to be trimmer and suffer from fewer diseases than Americans, who eat a diet high in protein and fat. McDougall also links osteoporosis to societies, like the United States and England, which have a higher intake of dietary protein. Again, he used as proof the Asian and African countries where protein is a smaller portion of peoples' diet.

LifeMatters Magazine is presenting this information in direct support of McDougall and his book The McDougall Program: 12 Days to Dynamic Health. The author seems to be presenting this vegetarian diet as a quick, flexible alternative to the standard, uncompromising weight loss plans. This plan emphasizes "optimum nutrition" and an end to calorie counting and hunger pains. Not only would this article encourage individuals to buy McDougall's book but also to buy this magazine to read all about it.

http://lifematters.com/mcdougl.html

 

Michael Klaper, MD, created a video entitled "Nutrition for Optimum Health." His vegetarian diet is based on six key nutrients; including protein, energy, vitamins, minerals, fiber, and water. Klaper claimed that the first five nutrients could all be found in plant-based foods such as grains, legumes, fruits & vegetables. He claims that "clean burning carbohydrates" fill the stomach and do it with little fat. Additionally, these carbohydrates will pass through the body quickly. His vegetarian diet avoids the dangers of the problem substances in cow's milk, as well as the high protein content of animal products that can lead to a deficiency of calcium in the bones, which contributes to osteoporosis. Klaper also makes the claim that fish are highly polluted these days. This article says that there are many alternative sources of calcium and protein that come from the earth. It is also possible to get sufficient vitamin B-12 without consuming animal products. Dr. Klaper goes to great lengths to explain a number of medical processes, including how animal fat deposits in your body and remains there and how calories from fat, protein & carbohydrates and starch fill your stomach differently, giving you a different sensation of "fullness." Despite the extensive explanations, there was really no evidence backing up his claims. He tried to validate his approach by taking a more personal approach. Klaper included his story of eliminating meat and dairy products from his own diet. He said he noticed a "wonderful change happening." Almost immediately, "24 pounds of fat melted right away," his cholesterol fell sharply, his blood pressure fell to normal levels again and he was not depriving himself at all. Other than his personal experience, there are no mentions of success with this vegetarian food plan. Also, the article begins with a disclaimer:

"The information herein is not given as medical advice. Before starting or changing any medical treatment please consult your physician." This information is presented in Dr. Klaper's words and is designed to promote and sell his video, "Nutrition for Optimum Health." There are many graphics and catchy charts, which might increase an individual's desire to purchase the video.

Http://www.newveg.av.org/health/optimum.htm

 

Scientific literature review of "Vegetarian Diets"

As was stated in the introduction, The American Dietetic Association (1993) supports vegetarian diets. According to their position statement, "a considerable body of scientific data suggest positive relationships between vegetarian diets and risk reduction for several chronic degenerative diseases and conditions, including obesity, coronary artery disease, hypertension, diabetes mellitus, and some types of cancer." The ADA considers the essential dietary nutrients and concludes that vegetarians can generally obtain the Recommended Dietary Allowances. As long as vegetarian diets include a wide variety of foods and enough calories to meet energy needs, the ADA only has five additional recommendations. These include: minimizing intake of sweets and fatty foods, choosing whole or unrefined grain products, eating a variety of fruits and vegetables, using low-fat or nonfat varieties of dairy products and limiting eggs to 3-4 yolks per week.

http://www.amhrt.org/Heart_and_Stroke_A_Z_Guide/vegdiet.html

 

In relation to disease and vegetarianism, a study was conducted by Key et al. (1996) to examine the association of dietary habits with mortality in vegetarians and health conscious people. In 1979 11,000 men and women were recruited through health food shops, vegetarian societies, and magazines. A questionnaire was used to assess their diet in terms of vegetarianism and fiber intake. At the six year follow-up a "vegetarian diet was associated with a significant reduction in mortality from ischaemic heart disease (775). In 1995, conclusions were drawn again. The same cohort had been followed until death and then cause of death was examined taking into consideration dietary patterns. At the 17-year follow up, a vegetarian diet and the consumption of whole-meal bread was not significantly associated (15% and 12% respectively) with the same reduction in mortality. However, there was an interesting finding that consuming fresh fruit daily was associated with a 24% reduction in mortality from ischaemic heart disease and a 32% reduction from cerebrovascular disease. Fruit can be considered a part of a diet high in fiber and definitely related to a vegetarian eating pattern. Nevertheless, no firm conclusions can be drawn. An additional finding supported an association between a vegetarian diet and a significant increase in mortality from breast cancer. These results could be due to chance as no other studies have reported this association (779).

In a study on the adequate calcium consumption of a vegetarian, Weaver and Plawecki (1994) concluded that "lactovegetarians are able to meet recommended calcium intakes and do not have compromised bone mineral densities" (1238S) and therefore do not seem to be at a greater risk for osteoporosis. Protein from animal products contains a high level of sulfur amino acids that can cause increased calcium loss through the kidneys. Therefore, vegetarians may be ingesting less calcium than nonvegetarians, but they are not losing as much either because the additional acids are not present. Weaver and Plawecki cited a study by Pederson et al (1991) that was conducted on two groups of pre-menopausal women. They found that the calcium intake of the vegetarians was not even significantly different than that of the nonvegetarians. Bone densities were also measured by dual photon absorptiometry and found to be the same between these two groups of women. This indicates that "lactovegetarians with calcium intakes above the RDA do not seem to be at increased risk for developing osteoporosis" (1239S).

Beilin and Burke (1995) examined the relationship between vegetarian diets and blood pressure. Generally they discovered that "evidence for a blood pressure lowering effect of a vegetarian dietary pattern comes from both population studies and randomized controlled trials involving dietary intervention" (195). These results could be explained in large part by a number of additional factors including the fact that vegetarians tend to be slimmer, smoke less, consume less alcohol, and are more physically active. However, a study was done comparing blood pressure in Seventh Day Adventists with Mormons to see if diet alone had an effect. These two groups were compared because they have very similar beliefs about tobacco, alcohol and caffeine yet their eating habits are quite different. Seventh Day Adventists are lacto-vegetarians and Mormons are meat eaters. The results of this study showed much lower blood pressure levels in the lacto-vegetarians that ate meat less than once a month. There are a number of nutrients, including fat, fiber, potassium and magnesium, that could be associated with the lower blood pressure in vegetarians. For example, vegetarians generally eat a diet high in fiber due to a higher consumption of fruits and vegetables and population studies have associated fiber intake with lower blood pressure in children and a decreased risk of hypertension in adults. However, it is still not clear which nutrients may be directly responsible for this difference.

Janelle and Barr (1995) conducted a study comparing vegetarians and nonvegetarians with similar health practices. Then, their nutrient intakes and eating behaviors were compared. Diet records were kept to assess nutrient intake while body compositions, dietary restraint and hunger were assessed by a questionnaire. The women in this study were all very health conscious and consumed a wide variety of nutrients with a mean fat intake that did not exceed 30% of energy. There were not many differences detected between the vegetarians and nonvegetarians. Fat intake was the same and although vegetarians had a consistently lower intake of protein, cholesterol, vitamin B-12 and zinc in this study, similar results in other studies have not been found. Most differences are usually only found between lactovegetarians and vegans. The interesting findings in this study have to do with the differences in dietary restraint. Although the vegetarians tended to be somewhat lighter and leaner, their scores on dietary restraint were lower than the nonvegetarians, suggesting less of a concern about body size. This finding is interesting considering the fact that many anorexics have traditionally considered themselves vegetarians. Dietary restraint, in this study, seemed to be affected more by body size than body composition. The "relatively heavier women perceived a greater need to limit energy intake (ie, had higher restraint scores) and reported consuming less energy" (186). This study did not seem to indicate that vegetarianism led to eating disorders although eating disorders have been associated with a vegetarian pattern of eating. Thus, "vegetarianism can be supportive of healthful eating attitudes and behaviors, and can provide another means of meeting current nutrition recommendations" (186).

 

Conclusion

 Based on the evidence collected and evaluated, vegetarian diets (including lactovegetarianism, ovo-lactovegetarianism, and semi-vegetarianism) is an effective way to ensure healthy living. There are some definite advantages to eliminating varying degrees of animal products from one's diet, primarily the lower mortality rate from many chronic degenerative diseases. Vegetarianism is also often found in individuals who exhibit other healthy lifestyle characteristics such as maintaining desirable weight, regular physical activity, and abstinence from smoking, alcohol, and illicit drugs. In addition, it has not been proven that vegetarianism is a causal factor in the onset of eating disorders. Many anorexics claim to be vegetarians but studies have not indicated that this lifestyle has led to the onset of a disorder. Individuals who have chosen not to consume animal products must just be careful to plan a diet that is rich in essential nutrients and has a caloric intake that will satisfy energy needs. If these considerations are made, The American Dietetic Association claims that "well-planned vegetarian diets can effectively meet these guidelines and can be a health-supporting dietary alternative."

 

 References

 Beilin, L.J. and Burke, V. (1995) Vegetarian Diet Components, Protein and Blood Pressure: Which Nutrients Are Important? Clinical and Experimental Pharmacology and Physiology, 22, 195-198.

Craig, Winston J. (1994) Iron Status of Vegetarians. American Journal of Clinical Nutrition, 59, 123-1237.

Janelle, Christina K. and Barr, Susan I. (1995) Nutrient Intakes and Eating Behavior Scores of Vegetarian and Nonvegetarian Women. Journal of the American Dietetic Association, 95, 180-186, 189.

 Key, Timothy J. A., Thorogood, Margaret, Appelby, Paul N. and Burr, Michael L. (1996) Dietary Habits and Mortality in 11,000 Vegetarians and Health Conscious People: Results of a 17 Year Follow Up. BMJ, 313, 775-779.

 Weaver, Connie M. and Plawecki, Karen L. (1994) Dietary Calcium: Adequacy of a Vegetarian Diet. American Journal of Clinical Nutrition, 59, 1238-1241.

 

 

 

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