Essentials of Complementary and Alternative Medicine (June 1999)



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L
IVING
 F
OODS
 D
IET
This diet was introduced by Ann Wigmore of the Hippocrates Institute in Boston. She believed that cooking destroyed many of the enzymes necessary for proper 
digestion and nutrient assimilation. The diet is composed of wheatgrass juice, fresh and fermented vegetables, fruits, and all variety of sprouted seed, grain, and 
legume. Although occasional use of raw milk or cheese is permitted, many followers make their own “seed milk” or “seed cheese” from ground, soaked seeds, such as 
rice or nuts.
C
OMMENTARY ON
 H
IGH
-F
IBER
, H
IGH
-C
ARBOHYDRATE
, L
OW
-F
AT
 D
IETS
These diets incorporate a plant-based eating plan, which translates into a high-fiber, low-fat pattern of eating. Nutritional epidemiology has consistently demonstrated 
that this type of diet is the most likely to lower the incidence of and mortality from chronic diseases Some studies also indicate that a plant-based diet may help 
increase the prospects of recovery and long-range survival after a diagnosis of cancer, diabetes, or heart disease. Substantial reductions in blood pressure, fasting 
serum glucose, total plasma cholesterol, and insulin dependency (among diabetics) have been documented following the low-fat, vegetable-based diets outlined in 
this section. When all fats are markedly restricted, however, deficiencies of omega-3 fatty acids and gamma linoleic acid (an important omega-6) may arise. These 
fatty acids may exert beneficial effects on the immune, nervous, and cardiovascular systems. Deficiencies in fat-soluble vitamins and gluten hypersensitivity may also 
develop. Physicians should closely monitor the nutritional status of patients who adhere to low-fat diets (10 to 15% of total calories as fat) without appropriate 
supplementation.
Vitamin B
12
 deficiency has been documented in rigidly vegan mothers and their nursing infants. Rickets, due to vitamin D deficiency, is also a concern in vegan 
children in northern climates. Avoidance of supplements and conventional medicine, due to an implicit belief in an “all natural” approach to health, can increase the 
risk of such complications. For people at risk of developing these deficiencies, vitamin supplements may be needed. Additionally, supplemental eicosapentaenoic acid 
(EPA) or fish oil may be desirable for patients who avoid fish, because many adults in the United States lack the enzymes that would enable them to convert 
plant-derived omega-3's (alpha-linolenic acid) into the biologically active compound EPA.
High-Protein, Low-Carbohydrate Diets
A
TKINS
 D
IET
Developed by Robert Atkins, MD, this diet emphasizes the consumption of nutrient-dense, unprocessed foods, avoidance of processed or refined carbohydrate foods, 
and use of nutrient supplements. High-carbohydrate meals (e.g., rice, breads, pasta) are thought to elicit excessive rises in insulin levels, which then result in fat 
accumulation. In addition, low-protein, low-fat meals tend to leave people less satisfied than meals high in fat and protein, which encourage the body to burn fat for 
energy. The supplementation component includes a full-spectrum multivitamin and an essential fatty acid formula.
Z
ONE
 D
IET
The Zone Diet, developed by Barry Sears, PhD, is similar to the Atkins diet–high protein (30%), low carbohydrate (40%), and moderately high fat (30%). Like Atkins, 
Sears contends that an excess of carbohydrates forces the body to oversecrete insulin, resulting in excess fat accumulation. Sears warns against the use of starchy 
foods, even high-fiber items such as whole-grain breads and pastas. Only high-fiber fruits and vegetables are allowed.
C
OMMENTARY ON
 H
IGH
-P
ROTEIN
, L
OW
-C
ARBOHYDRATE
 D
IETS
The rationale so ardently voiced by proponents of these diets is twofold. First, high-carbohydrate diets are thought to decrease insulin sensitivity over time and thus 
may increase an individual's vulnerability to the “metabolic syndrome” of insulin resistance (obesity, diabetes, hypertension, and cardiovascular disease). However, 
extensive research documents that high-fiber diets centered around complex carbohydrates increase insulin sensitivity (
33
), whereas diets relatively high in fat 
(and/or refined carbohydrates) tend to increase insulin resistance (
34

35
). The notion that thin people with elevated insulin levels are at risk is incorrect; these 
individuals do not, as a rule, have chronically elevated insulin levels. Increased consumption of low-glycemic foods that are high in complex carbohydrates will 
moderate insulin levels in these individuals in the context of a well-balanced nutritional program.
Second, low-carbohydrate proponents say that high-carbohydrate diets tend to increase blood triglyceride levels. Although it is true that some individuals who follow 
high-carbohydrate diets may have high triglyceride levels and low HDL cholesterol, low total cholesterol levels require less HDL to remove cholesterol. Increased 
triglyceride levels in the face of low-fat diets and low serum cholesterol levels are not likely to be important, unless other cardiovascular risk factors are present. 
Moreover, fish oil supplements (which can be used in selected cases) have been shown clinically to decrease the level of triglycerides and very low-density 
lipoproteins (VLDL) (
36

37
). High triglycerides are often associated with high intake of  refined carbohydrates, which are not recommended.
The relatively high-protein, high-fat profile of these diets is very appealing to many Americans because of its lenient attitude toward consumption of animal products. 
Most existing data, however, do not support the use of high-protein, low-carbohydrate diets for the establishment of good health. Rather, epidemiologic studies 
suggest that such diets, at the fat intake level of 30% of calories, increase the risk of heart disease, osteoporosis, kidney disorders, and various cancers, notably 
those involving the breast and colorectal tissues. Currently, the scientific literature suggests it is inadvisable for patients already diagnosed with these conditions to 
use either diet. Elderly patients and patients with renal disease should generally avoid such a regimen, even in the short term.
Diets of Variable Nutrient Composition
B
LOOD
 T
YPE
-B
ASED
 D
IET
Peter D'Adamo, MD, drawing from the work of his father, devised a dietary system based on the concept that the ideal diet depends on that aspect of genotype 
reflected in the blood type. The system consists of four different diets and four different exercise programs, all based on the four ABO blood types. The rationale 
derives primarily from the in vitro finding that specific lectins, present in many commonly eaten foods, can agglutinate the erythrocytes of certain blood types and exert 
a diverse range of biological effects. In theory, individuals with certain blood types will be adversely affected by specific lectins, whereas people with other blood types 
will react to other lectins; avoidance of foods that contain lectins incompatible with one's blood type enables individuals to lose weight, slow the aging process, and 
prevent common diseases.

K
ELLEY
 D
IET
 (M
ETABOLIC
 T
YPES
)
Dr. William Donald Kelley, an orthodontist from Texas, developed an anticancer dietary plan that was very similar to the Gerson diet, but with less stringent use of raw 
plant foods. Kelley developed 10 basic diets with numerous variations, depending on the type of cancer and on certain aspects of the patient's condition. These 
dietary plans range from vegan to red-meat-based diets. Kelley also recommended regular fasting, colonic irrigation (high enemas), and coffee enemas. Kelley also 
included pancreatic enzymes in the treatment of cancer patients. One of his students, Nicholas Gonzalez, MD, has subsequently included high levels of nutritional 
supplementation with micronutrients, amino acids, glandular substances, and digestive enzymes. These programs are individually designed with the goal of 
modulating sympathetic/parasympathetic imbalances.
A
YURVEDIC
 D
IET
Ayurveda, developed centuries ago in India, is the oldest medical system known, and its ancient texts span all the major branches of medicine. The Ayurvedic system 
of food and herbal selection revolves around the three  doshas, the innate tendencies that are built into an individual's total make-up. The three  doshasvitapitta, and 
kapha–manifest in different physical characteristics or metabolic body types. The  dosha refers to a unique property of the individual that enables one to adapt to one's 
environment either favorably or unfavorably. Factors such as stress and climate can alter each  dosha; imbalances in the doshas can result in specific diseases. 
Various foods, herbs, and emotions can either stabilize or disturb the balance of a given  dosha type. The Ayurvedic system is primarily vegetarian, although meat may 
be prescribed for certain  doshas (e.g., one with a predominance of vata) (see 
Chapter 11
 for a detailed description of this system).
N
ATURAL
 H
YGIENE
 D
IET
First formulated in the early 1800s by Sylvester Graham, this diet has been popularized by Harvey and Marilyn Diamond, authors of  Fit for Life. A central premise is 
proper food combinations to maximize digestion. Adherents follow specific rules about digestion, food selection, and usage. For example, fruits and vegetables are 
never eaten together, nor are protein- and starch-rich foods. Raw, unprocessed foods and freshly squeezed juices are emphasized, as are fresh vegetables, 
organically grown whenever possible. Occasional use of meat is allowed. Periodic fasting is practiced to remove accumulated toxins from the previous diet or 
environmental sources.
C
OMMENTARY ON
 D
IETS OF
 V
ARIABLE
 N
UTRIENT
 C
OMPOSITION
Several of these systems contain similar components that are part of the shifting paradigm of nutrition. Supporting any regimen that is low in fat and high in fiber, with 
minimal amounts of animal protein, is consistent with the preponderance of epidemiologic and laboratory data on good health. However, no one has performed the 
types of studies needed to validate these theories, and in some areas there are grounds for concern. For example, long-term adherence to the high-meat, type O diet 
(prescribed for more than 40% of the population) may raise the risk of heart disease and several cancers. The potential atherogenicity of this diet may be complicated 
further by the program's recommendation that type O individuals should avoid supplements of vitamin E and fish oil, both of which may help prevent heart disease. 
Similarly, one of the 10 diets in the Kelley program calls for raw meat as well as raw meat juices. The resulting high-protein load may cause excessive bone resorption 
and insulin-like growth factor secretion; also, there is risk of contamination with bacteria, particularly for those people with compromised immune systems.
The primarily vegetarian leaning of the Ayurvedic diet is likely to translate into general health improvements. At this time, however, there are limited published reports 
of the therapeutic effects of Ayurvedic dietary practices per se. In contrast, a number of studies have been published on the use of Ayurvedic herbal agents as dietary 
supplements. Similarly, the Natural Hygiene Diet has never been taken seriously by the medical establishment because there is no published evidence that this diet 
offers health benefits superior to any other low-fat vegetarian plan. The emphasis on proper digestion and food combination may be helpful to people who suffer from 
intestinal discomfort after eating.
In principle, the lack of cooked, high-fiber foods in a raw-foods regimen might be expected to produce deficiencies in various nutrients, because cooking (in 
moderation) helps release nutrients from many foods. Juicing and use of organically grown foods can reduce the risk of these deficiencies. There are many anecdotes 
supporting the use of this approach. In the author's clinical experience, however, raw-foods diets generally tend to be short-lived: adherents tend to increase their 
intake of energy-rich foods (nuts and nut butters) over time to compensate for the semifasting state, and they eventually switch back to regular consumption of 
high-calorie foods or cooked foods.
The potential health applications of these dietary approaches remain largely undetermined. Although there are some intriguing associations with blood types, lectins, 
and diseases, the blood-type theory of dietary selection rests on a set of as yet unsubstantiated assumptions about evolution and physiology. Documentation is scant 
for Ayurveda as well. This explains why such esoteric-sounding systems are usually shunned and chastised by medical professionals. However, we should remain 
open to the possibility that these noninvasive systems may have value. Scientific, clinically valid evaluations are needed before judgment can be passed in either 
direction.
MEDICAL APPLICATIONS OF NUTRITIONAL BIOTHERAPY
The extent of current knowledge on nutritional influences on disease etiology and progression is too vast for a single chapter. The aim of this section is to highlight 
major areas of clinical relevance whereby nutritional biotherapy may play a role, based on the evidence from nutritional epidemiology, with primary emphasis on 
clinical trials. The following is a discussion of the efficacy and use of nutritional intervention for four major diseases: cancer, hypertension, coronary heart disease, 
and diabetes.
Nutritional Biotherapy for Cancer
We have used nutritional biotherapy on two key areas of treatment in cancer: toxicity mitigation and potentiation of standard treatment. With regard to toxicity 
mitigation, intravenous supplementation with antioxidant nutrients can reduce the damage induced by peroxidation from chemotherapy or radiotherapy (
38

39
). 
Moreover, antioxidants improved the tolerance to chemotherapy and radiation (
40
). Fat- and water-soluble antioxidants may help alleviate the oxidative stress that 
accompanies many types of chemotherapy, as well as high-calorie diets, psychological stress, and the aging process (
4
). Importantly, the results of in vivo studies 
indicate that antioxidants will not simultaneously protect the tumor or interfere with the results of conventional treatment (
42

43

44

45

46

47

48

49

50

51
 and 
52
).
In the area of potentiating treatment, we now know that additive or synergistic relationships between nutrients and anticancer drugs may increase the therapeutic 
index, enabling lower doses of the chemotherapy agents to be used without diminishing tumor kill. In most therapeutic situations, the chemotherapy agents act by a 
direct cytotoxic effect, and the biomodulators simply amplify that effect. In some cases, the drugs may have immunomodulatory properties that synergize with 
immune-enhancing agents (
53
). For example, several trials demonstrated that vitamin A acted synergistically with chemotherapy and radiotherapy against metastatic 
cancers (
54

55
 and 
56
). When combined with the collagenase inhibitor minocycline (an anti-angiogenic agent), beta-carotene significantly enhanced the antitumor 
activities of several chemotherapy agents both in vitro and in vivo (
57
). Vitamin C potentiates the anticancer activity of chemotherapy agents in vivo (
58
) and in vitro 
(
59
), particularly when combined with vitamin K (
60

61

62

63
 and 
64
).
Evidence from both randomized and nonrandomized trials indicates that laboratory findings may carry over into the clinical realm. Survival and other clinical outcomes 
for chemotherapy-treated metastatic breast cancer have been improved with adjuvant use of high-dose oral vitamin A (
65

66

67

68

69
 and 
70
), antioxidant 
micronutrients and nutriceuticals (including coenzyme Q10) (
71

72

73
 and 
74
), L-arginine (
75

76
), and folinic acid (the reduced form of the B vitamin, folic acid) (
77

78

79

80
 and 
81
). Low-fat diets may further improve the prognosis of breast cancer patients (
82

83

84

85

86

87

88
 and 
89
), although randomized trials are 
needed to test this theory. In lung cancer patients, a randomized trial of adjuvant nutrition using high-dose vitamin A led to a significant reduction in tumor recurrences 
following surgery (
90
). Other retinoids may hold therapeutic promise for increasing response rates and survival in patients with advanced non-small-cell lung cancer 
(
91

92

93

94

95

96
 and 
97
), although response rates have been relatively low. A preliminary trial of small-cell lung cancer cases found that supplemental 
antioxidants resulted in significant improvements in expected survival (
98
). Significant prevention of bladder cancer recurrences has been demonstrated in 
randomized, placebo-controlled trials using vitamin B
6
 (
99
) and various retinoids (
100

101

102
 and 
103
) and, more recently, using multiple antioxidants at 
pharmacological doses versus the RDA for these micronutrients (
104
).
By far the strongest evidence for the efficacy of adjuvant nutrition, however, has been with various forms of leukemia. For example, clinical trials have demonstrated 
that all-trans retinoic acid (ATRA, or tretinoin, the acidic form of retinol) induced complete remission rates ranging from 86 to 100% and prolonged survival in acute 

promyelocytic leukemia patients (APL) (
105

106

107

108

109

110
 and 
111
). Patients with refractory or relapsed APL have also shown significant improvements in 
clinical response rates after ATRA supplementation (
112

113

114

115
 and 
116
). Patients diagnosed with advanced malignant melanoma may benefit by following 
low-protein, vegetable-rich diets (
117

118
) or by supplemental retinoids (
119

120
 and 
121
). Less well substantiated at this time is the efficacy of adjuvant nutrition for 
the treatment of pancreatic and prostate cancer and other gastrointestinal cancers, although there are promising preliminary reports.
Nutritional Biotherapy for Hypertension
The standard dietary advice for hypertensive patients consists of salt restriction, weight reduction (for obese patients), and reducing alcohol consumption (
122

123
). 
The first two of these have been shown to interact with each other in an additive fashion (
124

125
 and 
126
). Additionally, diets rich in fish, fruit, and vegetables have 
been shown to reverse mild hypertension, to enhance the effects of antihypertensive drugs, and to diminish fatal and nonfatal heart attack and stroke rates (
127
). 
Low-fat, plant-based diets are also likely to halt the progression of atherosclerotic and thrombotic disease. Other potentially useful antihypertensive strategies include 
antioxidant supplementation, cessation of smoking, and adoption of a regular exercise program (
128

129

130
 and 
131
). Similar strategies should be implemented in 
combination with appropriate medication for moderate to more severe forms of hypertension.
The effects of diet on blood pressure have been reviewed elsewhere (
132

133

134

135

136
 and 
137
). The most compelling data concerning an antihypertensive 
effect of low-fat, high-fiber diets come from a clinical study of the DASH diet (Dietary Approaches to Stop Hypertension ) (
138
) and from studies of vegetarians (
139

140

141

142

143

144

145

146
 and 
147
). Additionally, clinical trials and epidemiologic studies have demonstrated antihypertensive effects through seven 
strategies:
1. Sodium restriction (
148

149

150

151

152
 and 
153
).
2. Supplemental potassium (
154

155

156

157
 and 
158
).
3. Supplemental magnesium (
159

160
 and 
161
).
4. Supplemental calcium (
162

163
 and 
164
); however, this is for women only because of the risk for prostate cancer (
165
); in older women, calcium should be 
combined with magnesium to lower the risk of thrombosis (
166
).
5. Supplemental fish oil (
167

168
) (with restricted salt intake).
6. Vegetable oil (
169

170
 and 
171
).
7. Garlic (
172

173

174

175

176
 and 
177
).
Nutritional Biotherapy for Coronary Artery Disease (CAD)
Interventional cardiology refers not only to standard treatment (bypass surgery and angioplasty), but also to complementary management of CAD patients. 
Supplementation with soy protein (
178

179
 and 
180
), garlic extracts (
181

182
 and 
183
), coenzyme Q10 (
184

185
 and 
186
), magnesium (
187
), vitamin E (ideally with 
selenium) (
188

189
 and 
190
), or vitamin C (
191

192
 and 
193
) have demonstrated a range of beneficial therapeutic effects in the management of CAD patients. 
Additionally, omega-3 fatty acid supplements, either from fish oil or flaxseed oil, may be useful adjuncts to nutritional protocols for CAD (
194

195

196

197
 and 
198
). 
In the majority of clinical trials, supplemental use of fish oils significantly decreases the rate of restenosis following coronary angioplasty (
199

200

201

202

203

204

205

206
 and 
207
).
To date, seven clinical trials have demonstrated that a low-fat diet, usually in conjunction with cholesterol-lowering drugs, can alter coronary lesions and substantially 
retard CAD progression (
208

209

210

211

212

213

214

215

216

217
 and 
218
). In the highly publicized Lifestyle Heart Trial, Ornish et al. randomized 41 men 
and women to either usual care or a low-fat diet along with stress management (1 hour per day) and aerobic exercise (3 hours per day) (
3
). Subjects in the 
intervention group showed a decrease in average percentage diameter stenosis from 40 to 37.8%, whereas an increase was seen in the control group, 42.7 to 46.1% 
(p = 0.001) (
3
). After 4 years, the intervention showed an even greater improvement in stenosis and significant improvement in calculated coronary flow reserve; in 
contrast, patients in the control group had a further worsening of CAD progression (
219

220
). More recent follow-up has demonstrated continued benefits, including 
CAD regression, with long-term compliance on this program (
3
), although some have questioned the angiographic criteria used in this study (
22
).
A larger randomized study (n = 113) in Germany found overall delayed lesion progression in a diet-and-exercise intervention group (n = 56) versus controls (n = 57) 
(
222
). CAD progression was significantly retarded in the intervention group (23% versus 48%, p < 0.05), and regression was more pronounced in the intervention 
group as well (32% versus 17%, p <1 0.05) (
223
). Taken together, these trials suggest that optimal clinical outcomes for CAD treatment may be accomplished through 
the combined, individually tailored use of cholesterol-lowering drugs, bypass surgery, nutritional interventions, and lifestyle changes, such as exercise and stress 
management.
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