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Diet and Exercise: Effective Treatments for Type II Diabetes
Table of Contents
Today, over 16 million people, in America alone, suffer from diabetes. It is the main cause of kidney failure, limb amputations, hypertension, and new onset blindness, the major cause of heart disease and stroke (http://www.niddk.nih.gov/welcome/releases/8_8_01.htm), and the fourth leading cause of death by disease in the United States (http://home.judson.edu/academic/spinner/diabetes.html). However, of the total population afflicted, 95% of the cases are those of diabetes mellitus, more commonly referred to as type II diabetes, a life-long disease for which medicine has still no cure (http://www.activedayton.com/shared/health/adam/ency/article/000313.html).
Type II diabetes results from the body’s inability to produce sufficient amounts of insulin and from the body’s resistance of insulin by fat and muscle cells. In the latter case, the insulin secreted from the pancreas is unable to properly connect with the cell, therefore, not letting glucose, which is necessary for energy, in from the blood. As a result, blood glucose levels rise, causing the pancreas to produce more insulin. The cells, however, in detecting this glut of insulin, become even more resistant, leaving the afflicted person with high glucose levels, often high insulin levels (http://www.upmc.edu/newsbureau/wpic/diabetes_prevention_program.htm), and the inability to metabolize carbohydrates (http://home.judson.edu/academic/spinner/diabetes.html).
Lifestyle has been identified as the primary cause of type II diabetes. While smoking and behavioral skills are major contributors, diet and exercise are the main areas of concentration. By eating a healthy diet and exercising regularly, one can delay, reverse, and ultimately prevent the onset of type II diabetes. Even though genetics does play a part in the development of the disease, the adoption of a healthy lifestyle can significantly suppress the expression of the coded genes and, therefore, lessen a person’s chances of having to live a life complicated with type II diabetes. As Dr. Allen Spiegel, director of the National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK), commented, "Every year a person can live free of diabetes means an added year of life free of the pain, disability, and medical costs incurred by this disease" (http://www.niddk.nih.gov/welcome/releases/8_8_01.htm).
In diseases, such as type II diabetes, that are completely dependent on the proper functioning of the body on the cellular level, it is imperative to capitalize on those actions that aid the cells in their processes. Diet and exercise are such actions, seeing that each exerts tremendous influences on cellular activity. Moreover, according to the American Diabetes Association, the goal of any treatment plan for type II diabetics is to lower blood sugar and improve the body’s use of insulin; diet and exercise have both proved efficient in this regard (http://www.diabetes.org).
As stated by Christine Beebe, vice-president of the American Diabetes Association, "Diet is the cornerstone of diabetes therapy" (http://home.judson.edu/academic/spinner/diabetes.html). It carries the potential of balancing blood-glucose levels, establishing optimal lipid levels, and providing "adequate calories for maintaining or attaining reasonable weights in adults," three factors indispensable in treating type II diabetes, according to the American Diabetes Association's technical review, "Nutrition Principles for the Management of Diabetes and Related Complications" (page 1). No one specific diet plan is recognized by this review, the American Diabetes Association, or the American Dietetic Association; rather, experts are advocating a well-balanced diet that is individualized for each patient. However, general recommendations are being put forth. All of them closely resemble that of the American Dietetic Association’s, which recommends that 60-70% of total energy intake be divided between monounsaturated fats and carbohydrates, 10-20% be protein, 10% be saturated fat, no more than 10% be polyunsaturated fat, and a cholesterol intake of less than 300 mg per day (Lipkin, 1999).
According to the "Nutrition Principles for the Management of Diabetes and Related Complications," in type II diabetes, protein intake "may influence metabolic control by altering gluconeogenic substrate availability as well as insulin and counterregulatory hormone secretion." Also, in some type II diabetics, the ingestion of protein with glucose can trigger a "synergistic effect on the insulin secretion and a lower glycemic response than to glucose alone" (page 3). Fats and carbohydrates alter glucose and lipid metabolism. Fiber is known to aid in moderating blood sugar and blood-glucose levels and to aid in lowering the triglyceride levels and blood pressure (http://home.judson.edu/academic/spinner/diabetes.html). Low-fat, low-sugar, and high fiber foods slow the absorption of sugar into the bloodstream, which then causes the amount of insulin needed to be reduced by two or three units daily. In contrast, studies prove that when diabetics consume what Americans consider "moderate" intakes of meats, high-fat dairy products, and oils, the cell membranes become more resistant to insulin (http://www.cbn.com/partner/Article_Display_Page/0,,PTID2546%7CCHID102617%7CCIID135876,00.html).
In controlling type II diabetes, exercise is also essential. Exercise bears a high potential of improving glucose tolerance, enhancing cardiovascular health, reducing blood pressure and weight, and evoking positive changes in lipid profiles, all of which are key factors in treating type II diabetics. With its metabolic and cardiovascular benefits, exercise can significantly improve a diabetic's quality of life (Bell, 1992).
In type II diabetes, high blood glucose levels represent insulin resistance. Exercise increases insulin sensitivity and lowers body adiposity, which then ultimately improves the regulation of glucose levels (N S Pierce,1999, page 1). Exercise does this in several ways. First, it causes cells to demand glucose, which then triggers them to respond more readily to glucose, even if inadequate levels of insulin are present. Secondly, it causes an increase in insulin receptors, which, in turn, reduces blood glucose levels (http://home.judson.edu/academic/spinner/diabetes.html). Finally, the body naturally takes glucose out of the blood to use for energy during and after exercise. In the end, not only does exercise increase insulin sensitivity, but it also reduces the dose of insulin or oral medication needed (http://diabetes.roche.com/features/featureOct00.html).
Medical researchers claim that type II diabetes can not only be reversed, but prevented altogether. One of the strongest claims made to date appeared in the New England Journal of Medicine. It reported that if people exercised more, ate healthier food, stopped smoking, and adopted other healthy behavior 90 percent of all type II diabetes could be prevented (http://us.news2.yimg.com/f/42/31/7m/dailynews.yahoo.com/h/nm/20010912/sc/health_diabetes_dc_2.html). In addition, it has been claimed that through diet and exercise, the 10 million plus Americans at high risk for type II diabetes can substantially lower their chances of getting the disease (http://www.niddk.nih.gov/welcome/releases/8_8_01.htm). It has also been claimed that, in the words of Dr. Jakko Tuomilehto, "the incidence of type II diabetes mellitus can be reduced by as much as 58 percent through individualized intervention programs that encourage lifestyle modifications such as dietary changes and regular moderate exercise among patients at high risk for the disease" (http://www.findarticles.com/cf_dls/m3225/8_62/65864184/p1/article.jhtml), and in the words of a professor at the University of Texas, ‘Eighty-five percent of [type II] diabetes could be controlled through diet and exercise alone." (http://home.judson.edu/academic/spinner/diabetes.html).
The claims made about lifestyle intervention and the prevention of type II diabetes are strongly supported by the results of much in-depth research. A study conducted in Finland followed 523 Finns, all of whom were overweight and showed impaired glucose tolerance (IGT), a condition that generally precedes diabetes. Half the cohort was given intense instruction from dieticians and fitness professionals and given a free membership to a health club. The second half of the group received initial advice about the importance of diet and health, but no continual instruction. For two to six years, researches followed the two groups. Not only did they find that those participants in the first group were less likely to develop type II diabetes, but they also concluded that by losing as little as 10 pounds, increasing exercise, and sticking to a healthy diet, adults at high risk for type II diabetes could reduce their chances of contacting the disease by 60 percent. (http://www.findarticles.com/cf_dls/m3225/8_62/65864184/p1/article.html).
Pan and Associates (1997) reviewed the Da Qing IGT and Diabetes Study which also researched the efficacy of diet and exercise in preventing or delaying type II diabetes in people with impaired glucose tolerance (IGT). After screening 110,660 men and women from 33 different health care clinics in Da Qing, China, a cohort of 577 was selected, all having IGT, as defined by the World Health Organization. The subjects were randomly separated into a control group and three active treatment groups: diet only, exercise only, and diet-plus-exercise. The participants in each group were categorized by body mass index (BMI); of all the participants, 208 were found to be lean with BMI <25 kg/m2, and 332 were found to be overweight, with BMI >25 kg/m2.
In the diet group, each participant was prescribed a diet based on their BMI. Lean participants were assigned a diet containing 25-30 kcal/kg body weight, 55-65% carbohydrate, and 10-15% fat and were advised to consume more vegetables, control alcohol consumption, and reduce intake of simple sugars. Participants with BMI > 25 kg/m2 were encouraged to reduce their calorie intake to the point that they were losing weight at a rate of 0.5-1.0 kg per month. They were to continue this until the target BMI of 23 kg/m2. Thus, a unique diet plan was contrived for each participant, which outlined individual goals for total calorie consumption and daily quantities of cereals, vegetables, milk, meat, and oils. Each participant was counseled by a physician on daily food intake and in addition, small-group counseling sessions were conducted weekly one month, monthly for three months, and once every three months for the remaining term of the study.
In the exercise group, the participants were educated about exercise and encouraged to increase their amount of leisure physical exercise by 1-2 U/day, depending on age, any evidence of any health problems other than IGT, and past exercise patterns. The U represented one unit of exercise; a chart developed by the study dictated the intensity and duration of activity required for this one unit of exercise. In addition, all participants underwent the same schedule of counseling as the diet group, except without the initial counseling by a physician.
In the diet-plus-exercise group, participants received counseling on both diet and exercise which closely followed the schedule of the other two groups and were prescribed intervention tactics by the same standards as were followed by the diet-only and exercise-only groups. In contrast, participants in the control group received only general information about diabetes and IGT. Each participant was given a brochure with guidelines regarding diet and exercise, but no individual counseling was offered.
A six-year follow up of the study showed that the incidence of type II diabetes was reduced by 33% in the diet-only group, 47% in the exercise-only group, and 38% in the diet-plus exercise group; the incidence in the control group was 20-25% less than any other of the other groups. In the diet-only and diet-plus-exercise group, the estimated caloric intake was lower than the initial value, and in the exercise-only and exercise-plus-diet groups the average units per day of exercise was found to be significantly higher than at the start of the research. Ultimately, the study showed that over a six-year time period, changes in diet and exercise can considerably decrease the incidence of type II diabetes.
Other research has also been conducted in which the effects of diet and exercise on type II diabetes examined independently of one another. N S Peirce reviewed (1999) a number of such studies that concentrated solely on exercise and diabetes. He used the method of assessing sources through Medline, BIDS, and SportDiscuss from 1966 to 1998, and then cross referencing the material and considering the opinions of diabetologists and athletes to produce a thorough analysis of the relationship between exercise and diabetes. The review, based on strong and accurate evidence, (the major studies analyzed are already presented in this paper) overwhelmingly affirmed exercise as a potent strategy for the prevention and treatment of type II diabetes.
In another study, which focused just on diet, five men with normal glucose and insulin levels were given a lipid infusion to raise their levels of free fatty acids to levels considered "normal" for the typical American. Within two hours, all of the men had diabetes. Another research team conducted a similar study, but this time with four different groups, each set on a different diet – the first, high protein, the second, high fat, the third, no food, and the fourth, high carbohydrates. At the end of two days, only the high carbohydrate group maintained normal glucose levels; those individuals in the first group showed definite signs of diabetes, while those in the third group had fully developed the disease (http://home.judson.edu/academic/spinner/diabetes.html). In yet another study, eighty newly diagnosed type II diabetics who required insulin were placed on a sugar-free, 12% fat diet. Within six weeks of the study, 62% no longer required insulin and after eighteen weeks, 72% were completely free of the disease (http://home.judson.edu/academic/spinner/diabetes.html).
A research team, lead by Dr. Frank Hu of the Harvard School of Public Health, conducted a major ADA funded research study in which they followed 84,941 female nurses from 1980 to 1996, closely examining how the combined effect of diet and lifestyle contributed to the onset of type II diabetes mellitus in women (Hu et al., 2001). All the women were free of diagnosed cardiovascular disease, diabetes, and cancer at the base line, and information concerning individual diet and lifestyle was updated periodically through questionnaires. Based on questionnaire responses, a low-risk group was established according to a combination of variables, including a diet high in cereal fiber and polyunsaturated fat and low in trans-fat and glycemic load and engagement in moderate-to-vigorous physical activity for a minimum of thirty minutes per day.
The results showed that compared to the cohort as a whole, the women in the low-risk group had a 0.09 relative risk of developing type II diabetes. In addition, the study found that 91% of the developed cases of type II diabetes could be attributed to behavior not consistent with the low-risk pattern. Although the study found body mass index to be the most important risk factor, the study strongly acknowledged diet and exercise as major risk factors; it was even found women who exercised for less than thirty minutes weekly were twice as likely to develop type II diabetes as those who exercised for seven or more hours per week. (http://us.news2.yimg.com/f/42/31/7m/dailynews.yahoo.com/h/nm/20010912/sc/health_diabetes_dc_2.html).
The results of one study not only proved that exercise is effective in treating type II diabetes, but also determined the specific intensity and duration of physical activity necessary for exercise to be potent in combating the disease. The study analyzed 897 Finnish men and after adjustment for age, base-line glucose values, body mass index, serum triglyceride levels, parental history of diabetes, and alcohol consumption, found that moderately intensive physical activities, in those that were 5.5 metabolic units or higher and undertaken for at least 40 minutes per week, reduced the risk of developing non-insulin-dependent diabetes mellitus (NIDDM) by 50%. Activities with less than an intensity of 5.5 metabolic units did not prove protective, regardless of their duration. The study offered brisk walking on soft surfaces, slow swimming, light bicycling, aerobic dance, ball games, and commercially available exercise equipment all as examples of activities that would constitute an intensity of 5.5 metabolic units or greater. Moreover, the study showed that cardiovascular fitness levels greater than 31.0 mL of oxygen per kilogram per minute were protective against the onset of NIDDM and that exercise is also effective in men at high-risk of NIDDM. The study found that a subgroup of men who were categorized as high-risk due to being overweight, hypertensive and having a positive parental history of NIDDM, through exercising over 40-min/wk duration at intensities greater or equal to 5.5 metabolic units, were able to reduce their risk of developing NIDDM by 64% compared to men who did not engage in such activities. Clearly, physical activity and exercise play a major role in the onset and managing of type II diabetes (Cohen et al., 1995).
Of all the studies and research conducted, perhaps the most convincing and cogent findings came from a major clinical trial conducted by the Diabetes Prevention Program (DPP). It is a known statistic that different minority groups suffer disproportionately from type II diabetes; compared to whites, the disease is 50% more prevalent in African Americans and is 100 – 200% more prevalent in Hispanics (Martin et al ., 1995). Among other minorities subject to a disproportionate affliction rates are Asian Americans, Pacific Islanders, and American Indians. These minorities mentioned accounted for 45 percent of the 3,234 individuals the DPP followed in their study. The research team randomly assigned the cohort into two different groups – one to test the effectiveness of a potential drug and the other to test the effectiveness of lifestyle intervention.
Overall, the results of the second group echoed those of past studies, showing that those who ate healthier and exercised for just thirty minutes daily, reduced their risk of developing type II diabetes by 58 percent. What sets this study apart from the rest, however, is that its results prove that lifestyle intervention – namely diet and exercise – is just as effective in men and as it was in women and all the different ethnic groups. In addition, the results showed that in people age 60 or older, among whose prevalence for type II diabetes is 20 percent, their chances of developing the disease could be reduced by 71 percent through adapting their lifestyle (http://www.niddk.nih.gov/welcome/releases/8_8_01.htm).
Further studies prove not only that diet and exercise work, but that they are feasible forms of intervention as well. Barnard, Jung, and Inkeles' review (1994) of study in which a team of researchers established an intensive diet and exercise program and then investigated its effectiveness in controlling type II diabetes. The study identified 652 patients from 19 to 83 years of age, all of which had NIDDM. Of the cohort, 212 were taking insulin and 197 were taking oral hypoglycemic agents. All the patients participated in a 26-day lifestyle intervention program; the research team closely monitored their responses to it.
The program included daily aerobic exercise, primarily walking, and a high-complex-carbohydrate, high-fiber, low-fat, low-cholesterol, and low-salt diet, containing 35-40 g of dietary fiber per 1,000 kcal and a total daily intake < 4g of sodium chloride and < 25 mg of cholesterol. Of the total dietary calories, <10% were from fat, 15% were from protein, and the rest were from carbohydrates. The results showed that among the total cohort, fasting glucose levels were reduced from 10.0 to 8.45 mmol/l, serum total and low-density lipoprotein cholesterol were reduced by 22%, triglyceride levels were reduced by 33%, and the ratio of high-density lipoprotein cholesterol was reduced by 13%. At the end of the program, 39% of the 212 patients initially taking insulin and 71% of the 197 subjects initially taking oral hypoglycemic agents were all able to discontinue their medications. In addition, blood pressure was reduced considerably; of the 319 patients originally taking antihypertension drugs, 34% were able to discontinue their medications.
Not only did the program prove itself a success, but the results overwhelmingly showed that diet and exercise are absolute factors in controlling type II diabetes mellitus, and thus should be an integral part of any treatment therapy. In addition, the aftermath of the study presented two notably significant advantages of using diet and exercise as treatment. The first is that because the lifestyle interventions were so effective that overall health was improved and patients initially on medication and insulin were able to discontinue their usage, diet and exercise have the potential of dramatically lessening the medical costs of both the disease and its complications. The second advantage is that statistical evidence produced in the study showed that compliance rates are high with diet-exercise intervention; in the 2- to 3-year follow-up study, the majority of patients both continued the program and kept their diabetes under control.
A study conducted in Malmo, Sweden (Eriksson and Lindgarde,1991) not only resounded the effects diet and exercise have on type II diabetes, but also reinforced the feasibility of the interventions. Researchers performed a five-year prospective study, selecting 41 subjects with early-stage NIDDM as group one, 181 subjects with IGT as group two, 79 non-randomized subjects with IGT as group 3, and 114 randomly selected subjects with strictly normal OGTT as group 4. Groups one and two were enrolled in an intervention program at local clinics, which focused heavily on dietary advice and increase of physical activity, yet with no extreme resources being implemented. The participants were monitored through periodic check-ups. At the end of the study, 53.8% of the participants in the type II group (1) showed improved glucose levels and increased insulin sensitivity and were in remission. In the IGT group (2), 75.8% of the participants had improved their glucose tolerance and significantly increased insulin sensitivity, and only 10.6 % of group two had progressed to type II diabetes. The relative risk of the development of type II diabetes in group two compared to group three was found to be 0.37. In group four, no cases of diabetes were evident. Blood pressure was found to have been reduced in groups one, two, and three, yet a greater percentage of participants in group two than in group three were able to discontinue use of medication. In addition, the total plasma cholesterol dropped significantly in group one patients, lipid metabolism was improved in group two by a considerable reduction in type IV hyperlipidaemia, and serum triglycerides were substantially reduced in groups one and two, and increased in group three.
Furthermore, the drop-out rate for the 5-year intervention program was less than 10 %. This value is largely significant noting that the treatment groups (groups one and two) consisted of a representative sample of glucose tolerant subjects in the cohort, and not just a group of volunteers. Thus, the researchers concluded not only that diet and exercise were powerful forms of intervention, but also that the intervention program with a simple check-up process and moderate input of resources, could, in fact, be carried out on a large-scale community basis.
Adherence and Compliance
Evidence leaves no question that diet and exercise are effective and valuable intervention tactics. Thus, it would seem that diet and exercise are the simple solution to a major problem. However, overlooking the individual and social factors that impede adherence would be an largely unfair to those patients who struggle with self-managing programs.
Many of the studies took extraordinary measures to make sure the programs were as accessible and as encouraging as possible, such as frequent counseling visits, gym and work-out equipment available free of charge, and rigid meal plans. However, these and like measures, are not realistic to most who turn to diet and exercise for treatment of type II diabetes, thus making the integration of diet and exercise into one’s lifestyle far more difficult. In a 2001 issue of Journal of Community Health Nursing, researchers reported that despite the fact that diet and exercise are the essential components in controlling type II diabetes, they are the areas which patients find most difficult to comply and self-manage. The researchers conducted a study in which through mail, they surveyed 97 NIDDM patients from three eastern Washington area hospitals and 143 diabetes educators from the Washington Area Association of Education (WADE) on the difficulty of adhering to diet and exercise intervention programs. The patient and educator surveys both deemed the difficulty of maintaining a diet away from home and liking foods outside the meal plan to be the greatest inhibitors of self-managing a diet program, and weather and physical activity not being high priority as the greatest inhibitors of self-managing an exercise program. Another study, appearing in a 2000 Diabetes Care supplement, investigated the "limitations to treatment compliance of diabetes patients" (page 1). The study followed 354 diabetic patients, who were the total attendance to outpatient visits during one month at three different medical care centers; all patients were initially interviewed and a scale was developed to report compliance rates. It was found that, through the course of the study, diet had a 9.58% compliance, administration of insulin, a 39.13% compliance, and oral hypoglycemic agents, a 40.9% compliance, with the main limitation reported in these three treatments being cost. Of the subjects, 25.42% engaged in regular physical activities; those that did not, claimed unwillingness, physical disabilities, and insufficient knowledge as the greatest limitations. In all, 5.93 % of the participants had a total compliance, 52.54% had a partial compliance, and 41.53% had no compliance. The study concluded that "appropriate treatment compliance is low and that economic and social factors are the main limitations to achieve it" (Gutierrez & Rivas).
Fortunately, the medical field has identified the many difficulties patients have with compliance and are striving to develop methods to improve adherence. In the study, "Psychosocial Predictors of Self-Care Behaviors (Compliance) and Glycemic Control in Non-Insulin-Dependent Diabetes Mellitus" researchers were able to isolate (in order of importance) health beliefs, social support, knowledge, anxiety, and depression as the "psychosocial variables most predictive of adherence and establish suggested guidelines for physicians to follow in treating patients (Wilson and Associates, 1986). In 1999, another team of researches assessed the effect of behavioral science on self-management and patient empowerment in type II diabetics, with the conclusion that changes are required on the part of behavioral scientists and other health professionals in how they organize and present research and preventive therapies (Anderson et al., 1999). The Diabetes Control and Complications Trial (DCCT), found that "individualization of the intensive regimen, ongoing staff support, and follow-up contact" are central to improving adherence (Glasgow & Associates, 1999, page 1), and the "Physician and Patient Prevention Practices in NIDDM in a Large Urban Mangaged-Care Organization" study found that "improved access to preventive services may be effective in reducing" the adherence gap between different ethnicities and races. The researchers here studied 378 NIDDM patients who were members of the Kaiser Permanente Medical Care Program in Oakland, California in a cross-sectional chart review study of prevention practices, complications, and risk factors. Of the cohort, 232 were blacks, 81 were whites, 29 were Hispanics, and 36 were of other races and ethnicities (Martin et al., 1994, page 1). Furthermore, the American Diabetes Association, in it's review, "Diabetes Mellitus and Exercise," (2001) reported that adherence rates were highest in studies that implemented an initial period of supervision proceeded by moderately intense regular exercise program, that included regular and frequent follow-up assessments (http://www.diabetes.org/clinicalrecommendations/Supplement101/S51.htm).
The health profession is yielding the advice produced by research studies and is trying to implement the findings in treatment plans. Such examples are that the Division of Diabetes Translation is developing a distinct section of behavioral science, and in all 50 states, the Disease Control Programs, funded by the Disease Control and Prevention and Center (CDC’s) have invited behavioral scientists to become involved in their state’s program (Glasgow & Associates et al., 1999). Thus, action is being taken to improve adherence and therefore, enhance the effectiveness of diet and exercise intervention in type II diabetics.
Safety of the Treatments
Promoting a well-balanced diet and regular exercise program are essential components of health, regardless of whether a person is diabetic. A nutritional, well-balanced diet not only improves overall health and reduces the risk of long-term complications of type II diabetes such as renal disease, autonomic neuropathy, hypertension, and cardiovascular disease, but also significantly reduces the risk of chronic diseases such as obesity and dyslipidemias, that are on the rise in America today (Beebe et al., 1994). Although no specific diet has been set, all recommendations by the American Dietetic Association and American Diabetes Association are done so on the basis of maintaining and enhancing overall health.
Exercise, however, despite its proven ability to control glycemic levels and reduce the risk of cardiovascular disease, hyperlipidemia, hypertension, fibrinolysis, obesity, and type II diabetes, is not without risk for some patients. For example, for type II diabetics that are on insulin or undergoing sulfonylurea therapy, exercising when there not sufficient insulin circulating in the blood, due to inadequate therapy, increase glucose levels and ketone bodies and even initiate diabetic ketoacidosis. In contrast, if there is an excessive amount of insulin in the blood, exercise may inhibit proper mobilization of glucose and other exercise-induced substrates, thus, greatly increasing the risk of hypoglycemia. In order to best protect patients, a detailed and thorough evaluation complete with diagnostic studies must be done before any exercise program is recommended. The evaluation should determine if the patient shows any signs or symptoms of diseases that affect the circulatory or nervous systems, such as cardiovascular disease, peripheral arterial disease, retinopathy, and nephropathy, both peripheral and autonomic. In the event that evidence of such a disease is identified, an exercise program must be especially constructed to minimize the risk to the patient, seeing that certain forms and intensities of exercise could complicate the disease symptoms (2001). In any exercise program, however, the American Diabetes Association recommends a proper warm-up and cool-down consisting of 5-10 min of aerobic activity at a low-intensity level, proper stretching for 5-10 min after the warm-up. It also recommends that precautionary measures, such as silica gel or (blend) cotton-polyester socks, be taken in order to protect the feet from blisters and too much moisture, that proper hydration be practiced, due to the adverse effect dehydration can have on blood glucose levels and heart function, that hydration be properly maintained prior to exercise, and that high-resistance exercise be avoided for older individuals with long-standing diabetes (http://www.diabetes.org/clinicalrecommendations/Supplement101/S51.htm).
The evidence supporting the claims that diet and exercise are directly related to the development of type II diabetes is backed by sources that are both credible and sound. The researchers and medical organizations at the forefront of the issue, promoting such claims, are among the most respectable in the country. They include the Diabetes Prevention Program, the National Institutes of Health, the Centers for Disease Control and Prevention, the American Academy of Family Physicians, Harvard School of Public Health, the American Diabetes Association, and the Senate Select Committee on Nutrition and Human Needs, and others. In addition, the science journals and newspapers reporting the findings are held in high regard by the medical field. Such sources include the National Library of Medicine, the New England Journal of Medicine, and U.S. News.
The research organizations conducting the studies were not driven by profit or product sales; rather, they were motivated by the desire to find effective treatments and potential prevention tactics. These organizations and research teams are focused on preserving health and advancing the medical frontier, not in enticing customers. They present the findings to the public with the hope that the newfound knowledge might provoke lifestyle changes, which could ultimately reduce the number of people forced to live with type II diabetes.
According to a recent statistic, over 150 million people worldwide are afflicted with diabetes, and diabetes organizations are estimating that the number will be up to 300 million by 2005 (http://heartinfo.org/reuters2000/001114elin047.html). Fortunately, viable medical research has proved that there are indeed measures that can be taken to lessen the prevalence of the disease. The measures are as simple as eating a balanced diet and exercising regularly. Thus, the prevention and suppression of type II diabetes through diet and exercise are absolutely and completely feasible. Moreover, this correlation between lifestyle intervention and type II diabetes is merely a reflection of Dr. Denis Burkitt’s statement that, "Health is not determined by doctors of medicines; health is determined by the way we live" (http://home.judson.edu/academic/spinner/diabetes.html).
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