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McCarty MF. IGF-I activity may be a key determinant of stroke risk--a cautionary lesson for vegans. Med Hypotheses 2003; 61:323-34. [PMID: 12944100 DOI: 10.1016/s0306-9877(02)00241-4] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
IGF-I acts on vascular endothelium to activate nitric oxide synthase, thereby promoting vascular health; there is reason to believe that this protection is especially crucial to the cerebral vasculature, helping to ward off thrombotic strokes. IGF-I may also promote the structural integrity of cerebral arteries, thereby offering protection from hemorrhagic stroke. These considerations may help to explain why tallness is associated with low stroke risk, whereas growth hormone deficiency increases stroke risk--and why age-adjusted stroke mortality has been exceptionally high in rural Asians eating quasi-vegan diets, but has been declining steadily in Asia as diets have become progressively higher in animal products. There is good reason to suspect that low-fat vegan diets tend to down-regulate systemic IGF-I activity; this effect would be expected to increase stroke risk in vegans. Furthermore, epidemiology suggests that low serum cholesterol, and possibly also a low dietary intake of saturated fat--both characteristic of those adopting low-fat vegan diets--may also increase stroke risk. Vegans are thus well advised to adopt practical countermeasures to minimize stroke risk--the most definitive of which may be salt restriction. A high potassium intake, aerobic exercise training, whole grains, moderate alcohol consumption, low-dose aspirin, statin or policosanol therapy, green tea, and supplementation with fish oil, taurine, arginine, and B vitamins--as well as pharmacotherapy of hypertension if warranted--are other practical measures for lowering stroke risk. Although low-fat vegan diets may markedly reduce risk for coronary disease, diabetes, and many common types of cancer, an increased risk for stroke may represent an 'Achilles heel'. Nonetheless, vegans have the potential to achieve a truly exceptional 'healthspan' if they face this problem forthrightly by restricting salt intake and taking other practical measures that promote cerebrovascular health.
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Affiliation(s)
- M F McCarty
- Pantox Laboratories, San Diego, California 92109, USA
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102
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Jenkins DJA, Kendall CWC, Marchie A, Jenkins AL, Augustin LSA, Ludwig DS, Barnard ND, Anderson JW. Type 2 diabetes and the vegetarian diet. Am J Clin Nutr 2003; 78:610S-616S. [PMID: 12936955 DOI: 10.1093/ajcn/78.3.610s] [Citation(s) in RCA: 127] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Based on what is known of the components of plant-based diets and their effects from cohort studies, there is reason to believe that vegetarian diets would have advantages in the treatment of type 2 diabetes. At present there are few data on vegetarian diets in diabetes that do not in addition have weight loss or exercise components. Nevertheless, the use of whole-grain or traditionally processed cereals and legumes has been associated with improved glycemic control in both diabetic and insulin-resistant individuals. Long-term cohort studies have indicated that whole-grain consumption reduces the risk of both type 2 diabetes and cardiovascular disease. In addition, nuts (eg, almonds), viscous fibers (eg, fibers from oats and barley), soy proteins, and plant sterols, which may be part of the vegetarian diet, reduce serum lipids. In combination, these plant food components may have a very significant impact on cardiovascular disease, one of the major complications of diabetes. Furthermore, substituting soy or other vegetable proteins for animal protein may also decrease renal hyperfiltration, proteinuria, and renal acid load and in the long term reduce the risk of developing renal disease in type 2 diabetes. The vegetarian diet, therefore, contains a portfolio of natural products and food forms of benefit for both the carbohydrate and lipid abnormalities in diabetes. It is anticipated that their combined use in vegetarian diets will produce very significant metabolic advantages for the prevention and treatment of diabetes and its complications.
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Affiliation(s)
- David J A Jenkins
- Clinical Nutrition & Risk Factor Modification Center, St Michael's Hospital, Toronto, Ontario, Canada
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103
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McCarty MF. A wholly nutritional 'multifocal angiostatic therapy' for control of disseminated cancer. Med Hypotheses 2003; 61:1-15. [PMID: 12781633 DOI: 10.1016/s0306-9877(02)00227-x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
A great deal of effort is now being devoted to the development of new drugs that hopefully will control the spread of inoperable cancer by safely inhibiting tumor-evoked angiogenesis. However, there is growing evidence that certain practical nutritional measures have the potential to slow tumor angiogenesis, and it is reasonable to anticipate that, by combining several measures that work in distinct but complementary ways to impede the angiogenic process, a clinically useful 'multifocal angiostatic therapy' (MAT) might be devised. Several measures which might reasonably be included in such a protocol are discussed below, and include: a low-fat, low-glycemic index vegan diet, which may down-regulate the systemic IGF-I activity that supports angiogenesis; supplemental omega-3-rich fish oil, which has been shown to inhibit endothelial expression of Flk-1, a functionally crucial receptor for VEGF, and also can suppress tumor production of pro-angiogenic eicosanoids; high-dose selenium, which has recently been shown to inhibit tumor production of VEGF; green tea polyphenols, which can suppress endothelial responsiveness to both VEGF and fibroblast growth factor; and high-dose glycine, whose recently reported angiostatic activity may reflect inhibition of endothelial cell mitosis, possibly mediated by activation of glycine-gated chloride channels. In light of evidence that tumor-evoked angiogenesis has a high requirement for copper, copper depletion may have exceptional potential as an angiostatic measure, and is most efficiently achieved with the copper-chelating drug tetrathiomolybdate. If logistical difficulties make it difficult to acquire this experimental drug, high-dose zinc supplementation can achieve a slower depletion of the body's copper pool, and in any case can be used as maintenance therapy to maintain an adequate level of copper depletion. A provisional protocol is offered for a nutritionally based MAT entailing a vegan diet and supplemental intakes of fish oil, selenium, green tea polyphenols, glycine, and zinc. Inasmuch as cox-2 is overexpressed in many cancers, and cAMP can boost tumor production of various angiogenic factors as well as autogenous growth factors, adjunctive use of cox-2-specific NSAIDS may be warranted in some cases.
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Affiliation(s)
- M F McCarty
- Pantox Laboratories, San Diego, California 92129, USA
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104
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Sarri KO, Tzanakis NE, Linardakis MK, Mamalakis GD, Kafatos AG. Effects of Greek Orthodox Christian Church fasting on serum lipids and obesity. BMC Public Health 2003; 3:16. [PMID: 12753698 PMCID: PMC156653 DOI: 10.1186/1471-2458-3-16] [Citation(s) in RCA: 61] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2002] [Accepted: 05/16/2003] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND No study to date has focused on the impact of Greek Orthodox Christian fasting on serum lipoproteins and obesity yet. METHODS 120 Greek adults were followed longitudinally for one year. Sixty fasted regularly in all fasting periods (fasters) and 60 did not fast at all (controls). The three major fasting periods under study were: Christmas (40 days), Lent (48 days) and Assumption (August, 15 days). A total of 6 measurements were made during one year including pre- and end-fasting blood collection, serum lipoprotein analyses and anthropometric measurements. RESULTS Statistically significant end-fasting total and LDL cholesterol differences were found in fasters. Fasters compared to controls presented 12.5% lower end-total cholesterol (p < 0.001), 15.9% lower end-LDL cholesterol (p < 0.001) and 1.5% lower end-BMI (p < 0.001). The end- LDL/HDL ratio was lower in fasters (6.5%, p < 0.05) while the change in end- HDL cholesterol in fasters (4.6% decline) was not significant. Similar results were found when the pre- and end-fasting values of fasters were compared. No change was found in control subjects. CONCLUSIONS Adherence to Greek Orthodox fasting periods contributes to a reduction in the blood lipid profile including a non-significant reduction in HDL cholesterol and possible impact on obesity.
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Affiliation(s)
- Katerina O Sarri
- Department of Social Medicine, University of Crete, School of Medicine, P.O Box 1393, Iraklion 71110, Crete, Greece
| | - Nikolaos E Tzanakis
- Department of Social Medicine, University of Crete, School of Medicine, P.O Box 1393, Iraklion 71110, Crete, Greece
| | - Manolis K Linardakis
- Department of Social Medicine, University of Crete, School of Medicine, P.O Box 1393, Iraklion 71110, Crete, Greece
| | - George D Mamalakis
- Department of Social Medicine, University of Crete, School of Medicine, P.O Box 1393, Iraklion 71110, Crete, Greece
| | - Anthony G Kafatos
- Department of Social Medicine, University of Crete, School of Medicine, P.O Box 1393, Iraklion 71110, Crete, Greece
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105
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McCarty MF. A preliminary fast may potentiate response to a subsequent low-salt, low-fat vegan diet in the management of hypertension - fasting as a strategy for breaking metabolic vicious cycles. Med Hypotheses 2003; 60:624-33. [PMID: 12710893 DOI: 10.1016/s0306-9877(02)00228-1] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Although a salted diet appears to be a sine qua non for the development of essential hypertension, low-salt diets often have a modest or even negligible impact on the blood pressure of hypertensives; this suggests that salt, perhaps often acting in concert with other aspects of a modern, rich diet, may set in place certain metabolic vicious cycles that sustain blood pressure elevation even when dietary salt is eliminated. Therapeutic fasting is known to lower elevated blood pressure - presumably in large part because it minimizes insulin secretion - and may have the potential to break some of these vicious cycles. Goldhamer has recently reported that a regimen comprised of a water-only fast of moderate duration, followed by a transition to a low-fat, low-salt, whole-food vegan diet, achieves dramatic reductions in the blood pressure of hypertensives, such that the large majority of patients can be restored to normotensive status, in the absence of any drug therapy. Although long-term follow-up of these subjects has been sporadic, the available data suggest that these large reductions is blood pressure can be conserved in patients who remain compliant with the follow-up diet - in other words, a 'cure' for hypertension may be feasible. If a protein-sparing modified fast can be shown to be virtually as effective as a total fast for achieving these benefits, it may be possible to implement this regimen safely on an outpatient basis. The ability of therapeutic fasts to break metabolic vicious cycles may also contribute to the efficacy of fasting in the treatment of type 2 diabetes and autoimmune disorders. As a general principle, if a metabolic disorder is susceptible to prevention - but not reversal - by a specific diet, and therapeutic fasting has a temporary favorable impact on this disorder, then a more definitive therapy may consist of a therapeutic fast, followed up by the protective diet as a maintenance regimen.
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Affiliation(s)
- M F McCarty
- Pantox Laboratories, San Diego, California, USA
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106
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McCarty MF. Policosanol safely down-regulates HMG-CoA reductase - potential as a component of the Esselstyn regimen. Med Hypotheses 2002; 59:268-79. [PMID: 12208152 DOI: 10.1016/s0306-9877(02)00226-8] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Many of the wide-ranging health benefits conferred by statin therapy are mediated, not by reductions in LDL cholesterol, but rather by inhibition of isoprenylation reactions essential to the activation of Rho family GTPases; this may be the mechanism primarily responsible for the favorable impact of statins on risk for ischemic stroke, senile dementia, and fractures, as well as the anti-hypertensive and platelet-stabilizing actions of these drugs. Indeed, the extent of these benefits is such as to suggest that most adults would be wise to take statins; however, owing to the significant expense of statin therapy, as well as to the potential for dangerous side effects that mandates regular physician follow-up, this strategy appears impractical. However, policosanol, a mixture of long-chain aliphatic alcohols extractable from sugar cane wax, has shown cholesterol-lowering potency comparable to that of statins, and yet appears to be devoid of toxic risk. Recent evidence indicates that policosanol down-regulates cellular expression of HMG-CoA reductase, and thus has the potential to suppress isoprenylation reactions much like statins do. Consistent with this possibility, the results of certain clinical and animal studies demonstrate that policosanol has many effects analogous to those of statins that are not likely explained by reductions of LDL cholesterol. However, unlike statins, policosanol does not directly inhibit HMG-CoA reductase, and even in high concentrations it fails to down-regulate this enzyme by more than 50% - thus likely accounting for the safety of this nutraceutical. In light of the fact that policosanol is quite inexpensive and is becoming available as a non-prescription dietary supplement, it may represent a practical resource that could enable the general public to enjoy health benefits comparable to those conferred by statins. In a long-term clinical study enrolling patients with significant symptomatic coronary disease, Esselstyn has demonstrated that a low-fat, whole-food vegan diet, coupled with sufficient statin therapy to maintain serum cholesterol below 150 mg/dL, can stop the progression of coronary disease and virtually eliminate further risk for heart attack. A comparable regimen, in which policosanol is used in place of statins, may represent a practical strategy whereby nearly everyone willing to commit to health-protective eating can either prevent coronary disease, or prevent pre-existing coronary disease from progressing to a life-threatening event.
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107
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McCarty MF. Incorporation of beta cell redifferentiation therapy into a lipoprivic strategy for reversing type 2 diabetes. Med Hypotheses 2002; 58:462-71. [PMID: 12323111 DOI: 10.1054/mehy.2001.1454] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Type 2 diabetes (non-insulin-dependent diabetes mellitus, NIDDM), at least in the majority of patients characterized by insulin resistance and increased visceral fat, appears to be precipitated by the exposure of tissues to excessive levels of free fatty acids; this can contribute to the muscle insulin resistance, excessive hepatic gluconeogenesis, and beta cell dysfunction that collaborate to impair glycemic control. The resultant hyperglycemia, in turn, exacerbates the insulin resistance and beta cells dysfunction. The failure of glucose-stimulated insulin secretion (GSIS) in beta cells helps to sustain the elevations of serum glucose and free fatty acids, which in turn reinforce the failure of GSIS, possibly by inhibiting expression of the transcription factor IDX-1; NIDDM thus represents a vicious cycle that is not easily broken. A new strategy for achieving rapid loss of body fat - hepatothermic therapy (HT), an integrated approach involving exercise training, low-fat, low-glycemic-index food choices, and a supplementation program that promotes hepatic fatty acid oxidation - shows promise for alleviating the excessive fat exposure at the root of the diabetic syndrome, as well as the underlying insulin resistance syndrome responsible for increased macrovascular risk. However, when HT proves incapable of breaking the vicious cycle sustaining beta cell dysfunction, a supplementary strategy, beta cell redifferentiation therapy (BRT), may be required. BRT consists of a protocol in which near-normoglycemia is maintained for several weeks through use of intensive insulin therapy (e.g. artificial pancreas) or other effective measures, during which time beta cell GSIS can be expected to substantially recover owing to relief from glucolipotoxicity. Clinical experience demonstrates that this improved beta cell function, in certain cases, can persist for months or years after temporary BRT. A portion of the improved glycemic control achieved with very low calorie diets in NIDDM is reflective of improved GSIS, presumably consequent to a sustained reduction in diurnal glycemia. Long-lived analogs of glucagon-like peptide-1 (GLP-1) may find a key role in BRT; this incretin hormone not only potentiates GSIS, but also appears to increase the expression and activity of IDX-1 in beta cells, thus promoting beta cell redifferentiation. If HT is instituted prior to and following BRT to alleviate the FFA overexposure that initially precipitated the diabetic syndrome, it seems likely that the benefits of BRT will be conserved in the long term, thus enabling a reversal of NIDDM - in other words, maintenance of normoglycemia without medication. Since NIDDM is inherently preventable, its reversal should be the fundamental goal of diabetes therapy.
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108
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McCarty MF. Favorable impact of a vegan diet with exercise on hemorheology: implications for control of diabetic neuropathy. Med Hypotheses 2002; 58:476-86. [PMID: 12323113 DOI: 10.1054/mehy.2001.1456] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
A little-noticed clinical report indicates that a low-fat, whole-food vegan diet, coupled with daily walking exercise, leads to rapid remission of neuropathic pain in the majority of type 2 diabetics expressing this complication. Concurrent marked improvements in glycemic control presumably contribute to this benefit, but are unlikely to be solely responsible. Consideration should be given to the possibility that improved blood rheology - decreased blood viscosity and increased blood filterability - plays a prominent role in mediating this effect. There is considerable evidence that neural hypoxia, secondary to impaired endoneurial microcirculatory perfusion, is a crucial etiologic factor in diabetic neuropathy; the unfavorable impact of diabetes on hemorheology would be expected to exacerbate endoneurial ischemia. Conversely, measures which improve blood fluidity would likely have a beneficial impact on diabetic neuropathy. There is indeed evidence that vegan diets, as well as exercise training, tend to decrease the viscosity of both whole blood and plasma; reductions in hematocrit and in fibrinogen may contribute to this effect. The fact that vegan diets decrease the white cell count is suggestive of an improvement in blood filterability as well; filterability improves with exercise training owing to an increase in erythrocyte deformability. Whether these measures influence the activation of leukocytes in diabetics - an important determinant of blood filterability - remains to be determined. There are various reasons for suspecting that a vegan diet can reduce risk for other major complications of diabetes - retinopathy, nephropathy, and macrovascular disease - independent of its tendency to improve glycemic control in type 2 patients. The vegan diet/exercise strategy represents a safe, 'low-tech' approach to managing diabetes that deserves far greater attention from medical researchers and practitioners.
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109
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Iacopino AM. Periodontitis and diabetes interrelationships: role of inflammation. ANNALS OF PERIODONTOLOGY 2001; 6:125-37. [PMID: 11887455 DOI: 10.1902/annals.2001.6.1.125] [Citation(s) in RCA: 236] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Diabetes mellitus is a systemic disease with several major complications affecting both the quality and length of life. One of these complications is periodontal disease (periodontitis). Periodontitis is much more than a localized oral infection. Recent data indicate that periodontitis may cause changes in systemic physiology. The interrelationships between periodontitis and diabetes provide an example of systemic disease predisposing to oral infection, and once that infection is established, the oral infection exacerbates systemic disease. In this case, it may also be possible for the oral infection to predispose to systemic disease. In order to understand the cellular/molecular mechanisms responsible for such a cyclical association, one must identify common physiological changes associated with diabetes and periodontitis that produce a synergy when the conditions coexist. A potential mechanistic link involves the broad axis of inflammation, specifically immune cell phenotype, serum lipid levels, and tissue homeostasis. Diabetes-induced changes in immune cell function produce an inflammatory immune cell phenotype (upregulation of proinflammatory cytokines from monocytes/polymorphonuclear leukocytes and downregulation of growth factors from macrophages). This predisposes to chronic inflammation, progressive tissue breakdown, and diminished tissue repair capacity. Periodontal tissues frequently manifest these changes because they are constantly wounded by substances emanating from bacterial biofilms. Diabetic patients are prone to elevated low density lipoprotein cholesterol and triglycerides (LDL/TRG) even when blood glucose levels are well controlled. This is significant, as recent studies demonstrate that hyperlipidemia may be one of the factors associated with diabetes-induced immune cell alterations. Recent human studies have established a relationship between high serum lipid levels and periodontitis. Some evidence now suggests that periodontitis itself may lead to elevated LDL/TRG. Periodontitis-induced bacteremia/endotoxemia has been shown to cause elevations of serum proinflammatory cytokines such as interleukin-1 beta (IL-1 beta) and tumor necrosis factor-alpha (TNF-alpha), which have been demonstrated to produce alterations in lipid metabolism leading to hyperlipidemia. Within this context, periodontitis may contribute to elevated proinflammatory cytokines/serum lipids and potentially to systemic disease arising from chronic hyperlipidemia and/or increased inflammatory mediators. These cytokines can produce an insulin resistance syndrome similar to that observed in diabetes and initiate destruction of pancreatic beta cells leading to development of diabetes. Thus, there is potential for periodontitis to exacerbate diabetes-induced hyperlipidemia, immune cell alterations, and diminished tissue repair capacity. It may also be possible for chronic periodontitis to induce diabetes.
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Affiliation(s)
- A M Iacopino
- Division of Prosthodontics, Marquette University School of Dentistry, Milwaukee, Wisconsin, USA.
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110
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Abstract
New epidemiology confirms that glucose intolerance is a risk factor for pancreatic cancer, and that this association cannot be accounted for by an adverse impact of early pancreatic cancer on beta cell function. Previous reports indicate that risk for pancreatic cancer is increased in adult-onset diabetics. Since streptozotocin diabetes inhibits carcinogen-mediated induction of pancreatic cancer in hamsters, the most reasonable interpretation of these findings is that insulin (or some other beta cell product) acts as a promoter for pancreatic carcinogenesis. This view is consistent with a report that human pancreatic adenocarcinomas express insulin receptors that can stimulate mitosis; an additional possibility is that high insulin levels indirectly promote pancreatic carcinogenesis by boosting effective IGF-I activity via hepatic actions. In international ecologic epidemiology, pancreatic cancer rates correlate tightly with dietary intake of animal products; this may reflect the fact that vegan diets are associated with low diurnal insulin secretion. There is also suggestive evidence that macrobiotic vegan diets, which are low in glycemic index, may increase mean survival time in pancreatic cancer. However, other types of diets associated with decreased postprandial insulin response, such as high-protein diets or 'Mediterranean' diets high in oleic acid, may also have the potential for pancreatic cancer prevention. The huge increases of age-adjusted pancreatic cancer mortality in Japan and among African-Americans during the last century imply that pancreatic cancer is substantially preventable; a low-insulin-response diet coupled with exercise training, weight control, and smoking avoidance, commendable for a great many other reasons, may slash pancreatic cancer mortality dramatically.
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Affiliation(s)
- M F McCarty
- Pantox Laboratories, 4622 Santa Fe St, San Diego, CA 92109, USA
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