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Am J Prev Med The researchers examined the effects of different saturated fats and concluded that a diet rich in the types of saturated fat found in dairy had a protective effect against type 2 diabetes. Effect of plant sterols and glucomannan on lipids in individuals with and without type II diabetes. Adding protein to carbohydrate does not affect the glycemic response and does not prevent subsequent hypoglycemia. The Journal of Physiology. Latest publications The state of food security and nutrition in the world Capture the moment - Early initiation of breastfeeding: A diet that contains adequate amounts of amino acids especially those that are essential is particularly important in some situations:
A position statement of the American Diabetes Association
The demands of food technology in the production a dry kibble using the process of extrusion, same as breakfast cereal for humans dictate the macronutrient profile of dry pet foods. Extrusion is the expansion and "popping" of kibbles through a high heat, high pressure process that will not occur without substantial starch content in the slurry that is fed into the extruder.
A canned food formula, sent through an extruder, will end up a damp puddle the end of the machine, rather than fluffy, air filled kibbles ready for drying. So, tons of corn, rice, wheat, oats, barley and other grains the less expensive the better, of course are added to the meat meal and low volume ingredients that comprise dry pet foods because the product form will not materialize otherwise.
Further, dried kibble is almost completely unpalatable for the typical cat. This is not surprising; one would expect that this species would recognize high cereal foods as "not food. Few pet owners, including those adamantly opposed to the feeding of raw foods to their pets, would be so complacent about commercial dry pet foods if they witnessed the production and application of this ingredient.
Thus, cats are essentially "tricked" into the consumption of a food they would not ordinarily consume, through the application of tasty outer coatings. One is reminded of the application of candy coatings on the outside of children's breakfast cereal to enhance the consumption of relatively low nutritional-value breakfast foods. Now, contrast the formulation and production of dry cat foods with the formulation and production of canned or "wet foods.
Pates, even chunked, sliced, or grilled meats, go perfectly well into a sealed can that is then sterilized in a high-heat retort. Happily, high meat formulas are highly palatable for cats, who recognize such ingredients as appropriate foods for their nutritional needs, which they usually eat happily without additional palatability enhancers added. This is quite different from the macronutrient profile of dry foods, which are slave to the food technology of extrusion and the resulting need for intense palatability enhancement with "sugar coatings" of fermented digest post production.
The ingredients and macronutrients of the different forms of cat food are dictated by the requirements of food technology, not the science of feline nutrition. Many pet owners believe that commercial pet foods are safe and efficacious to feed to their pets because they have been "feeding trial tested" and shown to be complete and balanced by this method. The AAFCO statement on many pet foods bears testament to the fact that the contents of the can or bag have undergone some kind of feeding trial that guarantees that the food in the container is good for your pet.
This statement is extremely misunderstood by most pet owners and misleads them into believing that only good can come of feeding the product on which this statement appears. To illustrate this problem, let's go back in recent history.
In approximately , a young cardiology resident at the University of California at Davis by the name of Dr. Paul Pion noticed something rather interesting. One of his feline patients, a cat he was treating for congestive cardiomyopathy, had an extremely low serum taurine level.
Taurine is an essential amino acid in the cat meaning it cannot be synthesized in sufficient quantities by the cat to meet its ongoing needs and must be supplied in the diet , known to be required for proper eye and cardiac function in this and many other species. Pion's patient was fed an exclusive diet of a "high quality" premium commercial canned cat food, which should have supplied all of the taurine this cat required.
After all, the food was "feeding trial tested" and shown to be complete and balanced for all life stages in these feeding trials. Surely this cat's heart disease was not due to consumption of a taurine-deficient diet. Over the months following his initial observation, Dr.
Pion supplemented his original patient's diet with taurine and began to investigate other clinical cases of feline congestive cardiomyopathy. To his amazement, Dr. Pion discovered that virtually all of the cases he studied had low taurine levels in their bloodstream, and many of them improved dramatically, even returned to normal, when supplemented with taurine in addition to their regular diets, which were always canned commercial pet foods.
Most of these cats were fed diets that had been "feeding-trial-tested" and shown to be complete and balanced for the appropriate life stage by this method. How could foods produced by the "best" pet food manufacturers and tested according to the most stringent AAFCO guidelines be the direct cause of such pathologic deficiency in pet cats? The answer, although not immediately evident, became clear over the first few months of Dr.
The taurine in the implicated diets, often tested in the laboratory as adequate for the health of cats, was somehow not available to those cats when consumed in those diets. The processing of the canned formulations in the retort somehow "inactivated" the taurine contained in the foods so that it tested as adequate using laboratory methods, but in the "ultimate laboratory," the cat itself, the dietary taurine was not properly recognized and utilized.
If this were the case, however, why didn't the feeding trials of these foods disclose this terrible flaw? Because the vaunted feeding trials of which the companies and AAFCO are so proud are of such limited duration, usually no longer than 6 months, that only severe inadequacies and acute toxicities would ever be disclosed through them.
Further, had cats on a six-month feeding trial of a taurine-deficient diet developed congestive cardiomyopathy during the test period, it is extremely unlikely, prior to the problem discovered by Dr. Pion, that anyone would have recognized the condition as diet-related. Most cats would not become sufficiently deficient to develop overt clinical signs during the feeding trial. Thus, deficient diets were produced, feeding-trial-tested, and marketed for many years, causing the deaths of many cats, before a fortuitous turn of events and the keen observations of a young veterinarian allowed the problem to be identified and corrected.
The pet food companies and their "rigorous testing for safety and efficacy" allowed the development of a fatal disease in thousands of cats, and that had to be discovered and corrected through the efforts of an outsider who was not even a nutritionist. The "scientific teams" within the implicated companies themselves were stunned by the discovery.
The presently prevalent nutritional diseases of obesity and diabetes [ See Note 3 at bottom of page ] share stunning similarities with the taurine-deficiency disease of feline congestive cardiomyopathy. True enough, the disease associated with dietary taurine was a disease of nutrient deficiency, while diabetes and obesity in cats are diseases of nutrient excess.
Further, these diseases, and perhaps others yet to be uncovered in the future, are the result of an unfathomable failure by those most knowledgeable about the peculiar metabolic machinery and nutritional needs of the cat to properly consider those factors. By and large, the pet food industry has treated the cat like a "small dog," because it was expedient and seemed so harmless for so long.
Please note that not all cats that consume substantial dry cat food become obese, or develop diabetes, or idiopathic cystitis, at least not during the length of their lives, whatever that might be. Similarly, not all cats that consumed taurine-deficient canned foods in the s developed congestive cardiomyopathy, at least not before the link to canned foods was discovered and corrected. We know that as harmful as cigarette smoking clearly is for human beings, not every person that smokes cigarettes will develop cancer, or emphysema, or heart disease, at least not before some other cause of death intervenes.
These facts do not diminish in the slightest the unavoidable conclusions we have come to about the harmfulness of cigarette smoking, and the dangerousness of nutritionally deficient or excessive diets. Some people and animals are more resistant to environmental harms than others, but it is virtually impossible to tell which individuals these are before it is too late. Therefore, every individual in every susceptible population must be considered at risk.
What is to be done about the present rampant feeding of carbohydrate-laden dry cat foods? Shouldn't those who are gaining financially from the present high level of commercial pet food demand and who have the expertise to formulate and produce truly healthful feline diets, do so? Of course they should. The pet food companies that have set themselves up as the pet nutritional experts among us have the obligation to deliver the safety and efficacy they have been claiming for so long.
Unfortunately, without intense consumer pressure, that is highly unlikely to happen. All pet food companies have enormous investments in their current dry formulations and the long term purchase of ingredients that will make up those foods.
All have huge dry cat food plants and a customer base that they will not willingly convert to better types of food with smaller profit margins. Pion not discovered the taurine-deficiency connection to certain canned cat foods, and threatened the implicated companies with scathing public relations consequences if diet formulations were not immediately revamped and improved, we would still be treating congestive cardiomyopathy as a fatal disease of cats of "unknown etiology.
Pion's discovery and willingness to speak out loudly, feline congestive cardiomyopathy is essentially a historical disease today. If you worry about switching forms of food because you have been convinced that dry food is essential to good dental health for your cat, consider this: While the feeding of a crunchy kibble may have an intuitive appeal for dental health, the reality is that there are no scientific studies that prove dry foods provide better dental health throughout a cat's life than wet foods do.
In my practice, I have a majority of my patients consuming exclusively wet diets. My patients require no more regular dental care and experience no more disease of their teeth and gums than patients on other practices in which I have worked where dry food was the norm.
There is no dental benefit from dry food that even begins to offset the terrible harm done from feeding the wrong metabolic fuel to our cats. It is for us, all of us, to do as Dr. Pion did back in the late s. This article is the beginning of what I hope will become a groundswell of support to apply intense and constant pressure on the companies that supply our cat foods. I call for all of you to think long and hard about whether you really believe your cats are doing well on "fritos chips and breakfast cereal.
If you hesitate to seriously consider making a change from dry food because kibble is so convenient and easy to feed, please consider what this convenience is costing your cat.
Until the veterinary profession becomes more knowledgeable about feline nutrition, and the pet food industry faces and corrects the defects within its present dry formulations, you are your cat's only real advocate for nutritional health.
This is because of their extremely abnormal macronutrient profiles for an obligatory carnivore. Other canned foods have high levels of indigestible fiber wood cellulose , supposedly because this slows the absorption of sugar and calories from the food in which it is included. The foods do neither very well.
High fiber diets, canned and dry, limit the digestion and absorption of many vital nutrients, especially in a species with a short gastrointestinal tract and limited capability to extract nutrients from vegetation. They represent an irrational approach to meeting the nutritional needs of the overweight or diabetic cat and contain egregious amounts of simple carbohydrate, including carbohydrate and sugar from corn. This was believed to be the result of that company's fortuitous use of significantly greater amounts of fish in their canned cat food products than most other companies.
Fish is rich in taurine, and Iams' canned cat foods contained enough extra taurine to withstand harmful inactivation of that nutrient in the retort process. Further, the Iams Company more than any other has long insisted that the cat is a carnivore and should be fed as such.
This is clearly the right idea; unfortunately the Iams Company's dry foods are bursting with highly processed carbohydrate like every other company's.
The optimal macronutrient distribution of weight loss diets has not been established. Although low-fat diets have traditionally been promoted for weight loss, two randomized controlled trials found that subjects on low-carbohydrate diets lost more weight at 6 months than subjects on low-fat diets 19 , Another study of overweight women randomized to one of four diets showed significantly more weight loss at 12 months with the Atkins low-carbohydrate diet than with higher-carbohydrate diets 20a.
However, at 1 year, the difference in weight loss between the low-carbohydrate and low-fat diets was not significant and weight loss was modest with both diets. Changes in serum triglyceride and HDL cholesterol were more favorable with the low-carbohydrate diets.
In one study, those subjects with type 2 diabetes demonstrated a greater decrease in A1C with a low-carbohydrate diet than with a low-fat diet A recent meta-analysis showed that at 6 months, low-carbohydrate diets were associated with greater improvements in triglyceride and HDL cholesterol concentrations than low-fat diets; however, LDL cholesterol was significantly higher on the low-carbohydrate diets Further research is needed to determine the long-term efficacy and safety of low-carbohydrate diets Although brain fuel needs can be met on lower-carbohydrate diets, long-term metabolic effects of very-low-carbohydrate diets are unclear, and such diets eliminate many foods that are important sources of energy, fiber, vitamins, and minerals and are important in dietary palatability Meal replacements liquid or solid prepackaged provide a defined amount of energy, often as a formula product.
Use of meal replacements once or twice daily to replace a usual meal can result in significant weight loss. However, meal replacement therapy must be continued indefinitely if weight loss is to be maintained. When very-low-calorie diets are stopped and self-selected meals are reintroduced, weight regain is common. Thus, very-low-calorie diets appear to have limited utility in the treatment of type 2 diabetes and should only be considered in conjunction with a structured weight loss program.
All cardiovascular risk factors except hypercholesterolemia improved in the surgical patients. Individuals at high risk for type 2 diabetes should be encouraged to achieve the U. There is not sufficient, consistent information to conclude that low—glycemic load diets reduce the risk for diabetes. Nevertheless, low—glycemic index foods that are rich in fiber and other important nutrients are to be encouraged.
Observational studies report that moderate alcohol intake may reduce the risk for diabetes, but the data do not support recommending alcohol consumption to individuals at risk of diabetes. Although there are insufficient data at present to warrant any specific recommendations for prevention of type 2 diabetes in youth, it is reasonable to apply approaches demonstrated to be effective in adults, as long as nutritional needs for normal growth and development are maintained.
The importance of preventing type 2 diabetes is highlighted by the substantial worldwide increase in the prevalence of diabetes in recent years. Genetic susceptibility appears to play a powerful role in the occurrence of type 2 diabetes. However, given that population gene pools shift very slowly over time, the current epidemic of diabetes likely reflects changes in lifestyle leading to diabetes.
Lifestyle changes characterized by increased energy intake and decreased physical activity appear to have together promoted overweight and obesity, which are strong risk factors for diabetes. Several studies have demonstrated the potential for moderate, sustained weight loss to substantially reduce the risk for type 2 diabetes, regardless of whether weight loss was achieved by lifestyle changes alone or with adjunctive therapies such as medication or bariatricsurgery see energy balance section 1.
Moreover, both moderate-intensity and vigorous exercise can improve insulin sensitivity, independent of weight loss, and reduce risk for type 2 diabetes 1. S 26 strongly support the potential for moderate weight loss to reduce the risk for type 2 diabetes.
In addition to preventing diabetes, the DPP lifestyle intervention improved several CVD risk factors, including dsylipidemia, hypertension, and inflammatory markers 29 , The DPP analysis indicated that lifestyle intervention was cost-effective 31 , but other analyses suggest that the expected costs needed to be reduced Both the Finnish Diabetes Prevention study and the DPP focused on reduced intake of calories using reduced dietary fat as a dietary intervention.
Of note, reduced intake of fat, particularly saturated fat, may reduce risk for diabetes by producing an energy-independent improvement in insulin resistance 1 , 33 , 34 , as well as by promoting weight loss. It is possible that reduction in other macronutrients e. Several studies have provided evidence for reduced risk of diabetes with increased intake of whole grains and dietary fiber 1 , 35 — Whole grain—containing foods have been associated with improved insulin sensitivity, independent of body weight, and dietary fiber has been associated with improved insulin sensitivity and improved ability to secrete insulin adequately to overcome insulin resistance There is debate as to the potential role of low—glycemic index and —glycemic load diets in prevention of type 2 diabetes.
Thus, there is not sufficient, consistent information to conclude that low—glycemic load diets reduce risk for diabetes. Prospective randomized clinical trials will be necessary to resolve this issue. A American Diabetes Association statement reviewed this issue in depth 40 , and issues related to the role of glycemic index and glycemic load in diabetes management are addressed in more detail in the carbohydrate section of this document.
Observational studies suggest a U- or J-shaped association between moderate consumption of alcohol one to three drinks [15—45 g alcohol] per day and decreased risk of type 2 diabetes 41 , 42 , coronary heart disease CHD 42 , 43 , and stroke However, heavy consumption of alcohol greater than three drinks per day , may be associated with increased incidence of diabetes If alcohol is consumed, recommendations from the USDA Dietary Guidelines for Americans suggest no more than one drink per day for women and two drinks per day for men Although selected micronutrients may affect glucose and insulin metabolism, to date, there are no convincing data that document their role in the development of diabetes.
No nutrition recommendations can be made for the prevention of type 1 diabetes at this time 1. Increasing overweight and obesity in youth appears to be related to the increased prevalence of type 2 diabetes, particularly in minority adolescents. Although there are insufficient data at present to warrant any specific recommendations for the prevention of type 2 diabetes in youth, interventions similar to those shown to be effective for prevention of type 2 diabetes in adults lifestyle changes including reduced energy intake and regular physical activity are likely to be beneficial.
Clinical trials of such interventions are ongoing in children. A dietary pattern that includes carbohydrate from fruits, vegetables, whole grains, legumes, and low-fat milk is encouraged for good health.
Monitoring carbohydrate, whether by carbohydrate counting, exchanges, or experienced-based estimation remains a key strategy in achieving glycemic control. The use of glycemic index and load may provide a modest additional benefit over that observed when total carbohydrate is considered alone. Sucrose-containing foods can be substituted for other carbohydrates in the meal plan or, if added to the meal plan, covered with insulin or other glucose-lowering medications.
Care should be taken to avoid excess energy intake. As for the general population, people with diabetes are encouraged to consume a variety of fiber-containing foods. However, evidence is lacking to recommend a higher fiber intake for people with diabetes than for the population as a whole. Sugar alcohols and nonnutritive sweeteners are safe when consumed within the daily intake levels established by the Food and Drug Administration FDA. Control of blood glucose in an effort to achieve normal or near-normal levels is a primary goal of diabetes management.
Food and nutrition interventions that reduce postprandial blood glucose excursions are important in this regard, since dietary carbohydrate is the major determinant of postprandial glucose levels.
Low-carbohydrate diets might seem to be a logical approach to lowering postprandial glucose. However, foods that contain carbohydrate are important sources of energy, fiber, vitamins, and minerals and are important in dietary palatability.
Therefore, these foods are important components of the diet for individuals with diabetes. Issues related to carbohydrate and glycemia have previously been extensively reviewed in American Diabetes Association reports and nutrition recommendations for the general public 1 , 2 , 22 , 40 , Blood glucose concentration following a meal is primarily determined by the rate of appearance of glucose in the blood stream digestion and absorption and its clearance from the circulation Insulin secretory response normally maintains blood glucose in a narrow range, but in individuals with diabetes, defects in insulin action, insulin secretion, or both impair regulation of postprandial glucose in response to dietary carbohydrate.
Both the quantity and the type or source of carbohydrates found in foods influence postprandial glucose levels. A ADA statement addressed the effects of the amount and type of carbohydrate in diabetes management The 1-year follow-up data also indicate that the macronutrient composition of the treatment groups only differed with respect to carbohydrate intake mean intake of vs.
Thus, questions about the long-term effects on intake and metabolism, as well as safety, need further research. The amount of carbohydrate ingested is usually the primary determinant of postprandial response, but the type of carbohydrate also affects this response. Intrinsic variables that influence the effect of carbohydrate-containing foods on blood glucose response include the specific type of food ingested, type of starch amylose versus amylopectin , style of preparation cooking method and time, amount of heat or moisture used , ripeness, and degree of processing.
Extrinsic variables that may influence glucose response include fasting or preprandial blood glucose level, macronutrient distribution of the meal in which the food is consumed, available insulin, and degree of insulin resistance.
The glycemic index of foods was developed to compare the postprandial responses to constant amounts of different carbohydrate-containing foods The glycemic index of a food is the increase above fasting in the blood glucose area over 2 h after ingestion of a constant amount of that food usually a g carbohydrate portion divided by the response to a reference food usually glucose or white bread.
The glycemic loads of foods, meals, and diets are calculated by multiplying the glycemic index of the constituent foods by the amounts of carbohydrate in each food and then totaling the values for all foods. Foods with low glycemic indexes include oats, barley, bulgur, beans, lentils, legumes, pasta, pumpernickel coarse rye bread, apples, oranges, milk, yogurt, and ice cream. Fiber, fructose, lactose, and fat are dietary constituents that tend to lower glycemic response.
Potential methodological problems with the glycemic index have been noted Several randomized clinical trials have reported that low—glycemic index diets reduce glycemia in diabetic subjects, but other clinical trials have not confirmed this effect Moreover, the variability in responses to specific carbohydrate-containing food is a concern Nevertheless, a recent meta-analysis of low—glycemic index diet trials in diabetic subjects showed that such diets produced a 0.
However, it appears that most individuals already consume a moderate—glycemic index diet 39 , Thus, it appears that in individuals consuming a high—glycemic index diet, low—glycemic index diets can produce a modest benefit in controlling postprandial hyperglycemia. In diabetes management, it is important to match doses of insulin and insulin secretagogues to the carbohydrate content of meals.
A variety of methods can be used to estimate the nutrient content of meals, including carbohydrate counting, the exchange system, and experience-based estimation. By testing pre- and postprandial glucose, many individuals use experience to evaluate and achieve postprandial glucose goals with a variety of foods. To date, research has not demonstrated that one method of assessing the relationship between carbohydrate intake and blood glucose response is better than other methods.
Palatability, limited food choices, and gastrointestinal side effects are potential barriers to achieving such high-fiber intakes. Substantial evidence from clinical studies demonstrates that dietary sucrose does not increase glycemia more than isocaloric amounts of starch 1. Thus, intake of sucrose and sucrose-containing foods by people with diabetes does not need to be restricted because of concern about aggravating hyperglycemia.
Sucrose can be substituted for other carbohydrate sources in the meal plan or, if added to the meal plan, adequately covered with insulin or another glucose-lowering medication.
Additionally, intake of other nutrients ingested with sucrose, such as fat, need to be taken into account, and care should be taken to avoid excess energy intake. In individuals with diabetes, fructose produces a lower postprandial glucose response when it replaces sucrose or starch in the diet; however, this benefit is tempered by concern that fructose may adversely affect plasma lipids 1. Therefore, the use of added fructose as a sweetening agent in the diabetic diet is not recommended.
There is, however, no reason to recommend that people with diabetes avoid naturally occurring fructose in fruits, vegetables, and other foods. Reduced calorie sweeteners approved by the FDA include sugar alcohols polyols such as erythritol, isomalt, lactitol, maltitol, mannitol, sorbitol, xylitol, tagatose, and hydrogenated starch hydrolysates.
Studies of subjects with and without diabetes have shown that sugar alcohols produce a lower postprandial glucose response than sucrose or glucose and have lower available energy 1.
When calculating carbohydrate content of foods containing sugar alcohols, subtraction of half the sugar alcohol grams from total carbohydrate grams is appropriate. Use of sugar alcohols as sweeteners reduces the risk of dental caries. However, there is no evidence that the amounts of sugar alcohols likely to be consumed will reduce glycemia, energy intake, or weight. The use of sugar alcohols appears to be safe; however, they may cause diarrhea, especially in children.
The FDA has approved five nonnutritive sweeteners for use in the U. These are acesulfame potassium, aspartame, neotame, saccharin, and sucralose. Before being allowed on the market, all underwent rigorous scrutiny and were shown to be safe when consumed by the public, including people with diabetes and women during pregnancy.
Clinical studies involving subjects without diabetes provide no indication that nonnutritive sweeteners in foods will cause weight loss or weight gain It has been proposed that foods containing resistant starch starch physically enclosed within intact cell structures as in some legumes, starch granules as in raw potato, and retrograde amylose from plants modified by plant breeding to increase amylose content or high-amylose foods, such as specially formulated cornstarch, may modify postprandial glycemic response, prevent hypoglycemia, and reduce hyperglycemia.
However, there are no published long-term studies in subjects with diabetes to prove benefit from the use of resistant starch. Two or more servings of fish per week with the exception of commercially fried fish filets provide n-3 polyunsaturated fatty acids and are recommended.
The primary goal with respect to dietary fat in individuals with diabetes is to limit saturated fatty acids, trans fatty acids, and cholesterol intakes so as to reduce risk for CVD. Saturated and trans fatty acids are the principal dietary determinants of plasma LDL cholesterol. In nondiabetic individuals, reducing saturated and trans fatty acids and cholesterol intakes decreases plasma total and LDL cholesterol. Reducing saturated fatty acids may also reduce HDL cholesterol. Studies in individuals with diabetes demonstrating the effects of specific percentages of dietary saturated and trans fatty acids and specific amounts of dietary cholesterol on plasma lipids are not available.
Therefore, because of a lack of specific information, it is recommended that the dietary goals for individuals with diabetes be the same as for individuals with preexisting CVD, since the two groups appear to have equivalent cardiovascular risk. In metabolic studies in which energy intake and weight are held constant, diets low in saturated fatty acids and high in either carbohydrate or cis -monounsaturated fatty acids lowered plasma LDL cholesterol equivalently 1 , However, high—monounsaturated fat diets have not been shown to improve fasting plasma glucose or A1C values.
In other studies, when energy intake was reduced, the adverse effects of high-carbohydrate diets were not observed 53 , Individual variability in response to high-carbohydrate diets suggests that the plasma triglyceride response to dietary modification should be monitored carefully, particularly in the absence of weight loss.
Diets high in polyunsaturated fatty acids appear to have effects similar to monounsaturated fatty acids on plasma lipid concentrations 55 , 56 — Very-long-chain n-3 polyunsaturated fatty acid supplements have been shown to lower plasma triglyceride levels in individuals with type 2 diabetes who are hypertriglyceridemic.
Although the accompanying small rise in plasma LDL cholesterol is of concern, an increase in HDL cholesterol may offset this concern Glucose metabolism is not likely to be adversely affected. Very-long-chain n-3 polyunsaturated fatty acid studies in individuals with diabetes have primarily used fish oil supplements.
In addition to providing n-3 fatty acids, fish frequently displace high—saturated fat—containing foods from the diet Two or more servings of fish per week with the exception of commercially fried fish filets 63 , 64 can be recommended. Plant sterol and stanol esters block the intestinal absorption of dietary and biliary cholesterol. A wide range of foods and beverages are now available that contain plant sterols.
If these products are used, they should displace, rather than be added to, the diet to avoid weight gain. Soft gel capsules containing plant sterols are also available. In individuals with type 2 diabetes, ingested protein can increase insulin response without increasing plasma glucose concentrations.
Therefore, protein should not be used to treat acute or prevent nighttime hypoglycemia. High-protein diets are not recommended as a method for weight loss at this time. Although such diets may produce short-term weight loss and improved glycemia, it has not been established that these benefits are maintained long term, and long-term effects on kidney function for persons with diabetes are unknown.
The RDA is 0. Good-quality protein sources are defined as having high PDCAAS protein digestibility—corrected amino acid scoring pattern scores and provide all nine indispensable amino acids. Examples are meat, poultry, fish, eggs, milk, cheese, and soy. In meal planning, protein intake should be greater than 0. A number of studies in healthy individuals and in individuals with type 2 diabetes have demonstrated that glucose produced from ingested protein does not increase plasma glucose concentration but does produce increases in serum insulin responses 1 , Abnormalities in protein metabolism may be caused by insulin deficiency and insulin resistance; however, these are usually corrected with good blood glucose control However, the effects of high-protein diets on long-term regulation of energy intake, satiety, weight, and the ability of individuals to follow such diets long term have not been adequately studied.
Dietary protein and its relationships to hypoglycemia and nephropathy are addressed in later sections. Although numerous studies have attempted to identify the optimal mix of macronutrients for the diabetic diet, it is unlikely that one such combination of macronutrients exists. The best mix of carbohydrate, protein, and fat appears to vary depending on individual circumstances. For those individuals seeking guidance as to macronutrient distribution in healthy adults, the Dietary Reference Intakes DRIs may be helpful It must be clearly recognized that regardless of the macronutrient mix, total caloric intake must be appropriate to weight management goals.
Further, individualization of the macronutrient composition will depend on the metabolic status of the patient e. If adults with diabetes choose to use alcohol, daily intake should be limited to a moderate amount one drink per day or less for women and two drinks per day or less for men.
To reduce risk of nocturnal hypoglycemia in individuals using insulin or insulin secretagogues, alcohol should be consumed with food. In individuals with diabetes, moderate alcohol consumption when ingested alone has no acute effect on glucose and insulin concentrations but carbohydrate coingested with alcohol as in a mixed drink may raise blood glucose. Abstention from alcohol should be advised for people with a history of alcohol abuse or dependence, women during pregnancy, and people with medical problems such as liver disease, pancreatitis, advanced neuropathy, or severe hypertriglyceridemia.
If individuals choose to use alcohol, intake should be limited to a moderate amount less than one drink per day for adult women and less than two drinks per day for adult men. One alcohol containing beverage is defined as 12 oz beer, 5 oz wine, or 1. Moderate amounts of alcohol, when ingested with food, have minimal acute effects on plasma glucose and serum insulin concentrations However, carbohydrate coingested with alcohol may raise blood glucose.
For individuals using insulin or insulin secretagogues, alcohol should be consumed with food to avoid hypoglycemia. Evening consumption of alcohol may increase the risk of nocturnal and fasting hypoglycemia, particularly in individuals with type 1 diabetes Occasional use of alcoholic beverages should be considered an addition to the regular meal plan, and no food should be omitted.
Excessive amounts of alcohol three or more drinks per day , on a consistent basis, contributes to hyperglycemia In individuals with diabetes, light to moderate alcohol intake one to two drinks per day; 15—30 g alcohol is associated with a decreased risk of CVD The type of alcohol-containing beverage consumed does not appear to make a difference.
There is no clear evidence of benefit from vitamin or mineral supplementation in people with diabetes compared with the general population who do not have underlying deficiencies. Routine supplementation with antioxidants, such as vitamins E and C and carotene, is not advised because of lack of evidence of efficacy and concern related to long-term safety. Benefit from chromium supplementation in individuals with diabetes or obesity has not been clearly demonstrated and therefore can not be recommended.
Uncontrolled diabetes is often associated with micronutrient deficiencies Individuals with diabetes should be aware of the importance of acquiring daily vitamin and mineral requirements from natural food sources and a balanced diet.
Health care providers should focus on nutrition counseling rather than micronutrient supplementation in order to reach metabolic control of their patients. Research including long-term trials is needed to assess the safety and potentially beneficial role of chromium, magnesium, and antioxidant supplements and other complementary therapies in the management of type 2 diabetes 71a , 71b.
In select groups such as the elderly, pregnant or lactating women, strict vegetarians, or those on calorie-restricted diets, a multivitamin supplement may be needed 1. Since diabetes may be a state of increased oxidative stress, there has been interest in antioxidant therapy. Unfortunately, there are no studies examining the effects of dietary intervention on circulating levels of antioxidants and inflammatory biomarkers in diabetic volunteers.
The few small clinical studies involving diabetes and functional foods thought to have high antioxidant potential e.
Clinical trial data not only indicate the lack of benefit with respect to glycemic control and progression of complications but also provide evidence of the potential harm of vitamin E, carotene, and other antioxidant supplements 1 , 72 , In addition, available data do not support the use of antioxidant supplements for CVD risk reduction Chromium, potassium, magnesium, and possibly zinc deficiency may aggravate carbohydrate intolerance.
Serum levels can readily detect the need for potassium or magnesium replacement, but detecting deficiency of zinc or chromium is more difficult In the late s, two randomized placebo-controlled studies in China found that chromium supplementation had beneficial effects on glycemia 76 — 78 , but the chromium status of the study populations was not evaluated either at baseline or following supplementation.
Data from recent small studies indicate that chromium supplementation may have a role in the management of glucose intolerance, gestational diabetes mellitus GDM , and corticosteroid-induced diabetes 76 — However, other well-designed studies have failed to demonstrate any significant benefit of chromium supplementation in individuals with impaired glucose intolerance or type 2 diabetes 79 , Similarly, a meta-analysis of randomized controlled trials failed to demonstrate any benefit of chromium picolinate supplementation in reducing body weight The FDA concluded that although a small study suggested that chromium picolinate may reduce insulin resistance, the existence of such a relationship between chromium picolinate and either insulin resistance or type 2 diabetes was uncertain http: There is insufficient evidence to demonstrate efficacy of individual herbs and supplements in diabetes management In addition, commercially available products are not standardized and vary in the content of active ingredients.
Herbal preparations also have the potential to interact with other medications Therefore, it is important that health care providers be aware when patients with diabetes are using these products and look for unusual side effects and herb-drug or herb-herb interactions. Individuals using rapid-acting insulin by injection or an insulin pump should adjust the meal and snack insulin doses based on the carbohydrate content of the meals and snacks.
For individuals using fixed daily insulin doses, carbohydrate intake on a day-to-day basis should be kept consistent with respect to time and amount. For planned exercise, insulin doses can be adjusted. For unplanned exercise, extra carbohydrate may be needed. The first nutrition priority for individuals requiring insulin therapy is to integrate an insulin regimen into their lifestyle.
For individuals receiving basal-bolus insulin therapy, the total carbohydrate content of meals and snacks is the major determinant of bolus insulin doses Insulin-to-carbohydrate ratios can be used to adjust mealtime insulin doses. Several methods can be used to estimate the nutrient content of meals, including carbohydrate counting, the exchange system, and experience-based estimation. Improvement in A1C without a significant increase in severe hypoglycemia was demonstrated, as were positive effects on quality of life, satisfaction with treatment, and psychological well-being, even though increases in the number of insulin injections and blood glucose tests were necessary.
For planned exercise, reduction in insulin dosage is the preferred method to prevent hypoglycemia For unplanned exercise, intake of additional carbohydrate is usually needed.
More carbohydrate is needed for intense activity. A American Diabetes Association statement addresses diabetes MNT for children and adolescents with type 1 diabetes Individuals with type 2 diabetes are encouraged to implement lifestyle modifications that reduce intakes of energy, saturated and trans fatty acids, cholesterol, and sodium and to increase physical activity in an effort to improve glycemia, dyslipidemia, and blood pressure.
Plasma glucose monitoring can be used to determine whether adjustments in foods and meals will be sufficient to achieve blood glucose goals or if medication s needs to be combined with MNT.
Healthy lifestyle nutrition recommendations for the general public are also appropriate for individuals with type 2 diabetes. Because many individuals with type 2 diabetes are overweight and insulin resistant, MNT should emphasize lifestyle changes that result in reduced energy intake and increased energy expenditure through physical activity.
Because many individuals also have dyslipidemia and hypertension, reducing saturated and trans fatty acids, cholesterol, and sodium is often desirable. Therefore, the first nutrition priority is to encourage individuals with type 2 diabetes to implement lifestyle strategies that will improve glycemia, dyslipidemia, and blood pressure. Although there are similarities to those above for type 1 diabetes, MNT recommendations for established type 2 diabetes differ in several aspects from both recommendations for type 1 diabetes and the prevention of diabetes.
MNT progresses from prevention of overweight and obesity, to improving insulin resistance and preventing or delaying the onset of diabetes, and to contributing to improved metabolic control in those with diabetes. With established type 2 diabetes treated with fixed doses of insulin or insulin secretagogues, consistency in timing and carbohydrate content of meals is important.
However, rapid-acting insulins and rapid-acting insulin secretagogues allow for more flexible food intake and lifestyle as in individuals with type 1 diabetes.
Increased physical activity by individuals with type 2 diabetes can lead to improved glycemia, decreased insulin resistance, and a reduction in cardiovascular risk factors, independent of change in body weight. Resistance training is also effective in improving glycemia and, in the absence of proliferative retinopathy, people with type 2 diabetes can be encouraged to perform resistance exercise three times a week Adequate energy intake that provides appropriate weight gain is recommended during pregnancy.
Weight loss is not recommended; however, for overweight and obese women with GDM, modest energy and carbohydrate restriction may be appropriate. MNT for GDM focuses on food choices for appropriate weight gain, normoglycemia, and absence of ketones. Because GDM is a risk factor for subsequent type 2 diabetes, after delivery, lifestyle modifications aimed at reducing weight and increasing physical activity are recommended. Prepregnancy MNT includes an individualized prenatal meal plan to optimize blood glucose control.
Due to the continuous fetal draw of glucose from the mother, maintaining consistency of times and amounts of food eaten are important to avoidance of hypoglycemia. Plasma glucose monitoring and daily food records provide valuable information for insulin and meal plan adjustments.
MNT for GDM primarily involves a carbohydrate-controlled meal plan that promotes optimal nutrition for maternal and fetal health with adequate energy for appropriate gestational weight gain, achievement and maintenance of normoglycemia, and absence of ketosis.
Specific nutrition and food recommendations are determined and subsequently modified based on individual assessment and self-monitoring of blood glucose.
A recent large clinical trial reported that treatment of GDM with nutrition therapy, blood glucose monitoring, and insulin therapy as required for glycemic control reduced serious perinatal complications without increasing the rate of cesarean delivery as compared with routine care Maternal health—related quality of life was also improved.
Hypocaloric diets in obese women with GDM can result in ketonemia and ketonuria. Insufficient data are available to determine how such diets affect perinatal outcomes.
Daily food records, weekly weight checks, and ketone testing can be used to determine individual energy requirements and whether a woman is undereating to avoid insulin therapy. Carbohydrate should be distributed throughout the day in three small- to moderate-sized meals and two to four snacks. An evening snack may be needed to prevent accelerated ketosis overnight. Carbohydrate is generally less well tolerated at breakfast than at other meals.
Regular physical activity can help lower fasting and postprandial plasma glucose concentrations and may be used as an adjunct to improve maternal glycemia. If insulin therapy is added to MNT, maintaining carbohydrate consistency at meals and snacks becomes a primary goal. Although most women with GDM revert to normal glucose tolerance postpartum, they are at increased risk of GDM in subsequent pregnancies and type 2 diabetes later in life. Lifestyle modifications after pregnancy aimed at reducing weight and increasing physical activity are recommended, as they reduce the risk of subsequent diabetes 26 , Breast-feeding is recommended for infants of women with preexisting diabetes or GDM; however, successful lactation requires planning and coordination of care In most situations, breast-feeding mothers require less insulin because of the calories expended with nursing.
Lactating women have reported fluctuations in blood glucose related to nursing sessions, often requiring a snack containing carbohydrate before or during breast-feeding Obese older adults with diabetes may benefit from modest energy restriction and an increase in physical activity; energy requirement may be less than for a younger individual of a similar weight.
A daily multivitamin supplement may be appropriate, especially for those older adults with reduced energy intake. Physical activity is needed to attenuate loss of lean body mass that can occur with energy restriction. Exercise training can significantly reduce the decline in maximal aerobic capacity that occurs with age, improve risk factors for atherosclerosis, slow the age-related decline in lean body mass, decrease central adiposity, and improve insulin sensitivity—all potentially beneficial for the older adult with diabetes 89 , However, exercise can also pose potential risks such as cardiac ischemia, musculoskeletal injuries, and hypoglycemia in patients treated with insulin or insulin secretagogues.
Reduction of protein intake to 0. MNT that favorably affects cardiovascular risk factors may also have a favorable effect on microvascular complications such as retinopathy and nephropathy.
Progression of diabetes complications may be modified by improving glycemic control, lowering blood pressure, and, potentially, reducing protein intake.
In several studies of subjects with diabetes and microalbuminuria, urinary albumin excretion rate and decline in glomerular filtration were favorably influenced by reduction of protein intake to 0.
Although reduction of protein intake to 0. In individuals with diabetes and macroalbuminuria, reducing protein from all sources to 0. Although several studies have explored the potential benefit of plant proteins in place of animal proteins and specific animal proteins in diabetic individuals with microalbuninuria, the data are inconclusive 1 , Observational data suggest that dyslipidemia may increase albumin excretion and the rate of progression of diabetic nephropathy Elevation of plasma cholesterol in both type 1 and 2 diabetic subjects and plasma triglycerides in type 2 diabetic subjects were predictors of the need for renal replacement therapy Whereas these observations do not confirm that MNT will affect diabetic nephropathy, MNT designed to reduce the risk for CVD may have favorable effects on microvascular complications of diabetes.
For patients with diabetes at risk for CVD, diets high in fruits, vegetables, whole grains, and nuts may reduce the risk. In normotensive and hypertensive individuals, a reduced sodium intake e. In most individuals, a modest amount of weight loss beneficially affects blood pressure. In the EDIC Epidemiology of Diabetes Interventions and Complications study, the follow-up of the DCCT Diabetes Control and Complications Trial , intensive treatment of type 1 diabetic subjects during the DCCT study period improved glycemic control and significantly reduced the risk of the combined end point of cardiovascular death, myocardial infarction, and stroke Adjustment for A1C explained most of the treatment effect.
The risk reductions obtained with improved glycemia exceeded those that have been demonstrated for other interventions such as cholesterol and blood pressure reductions. There are no large-scale randomized trials to guide MNT recommendations for CVD risk reduction in individuals with type 2 diabetes. However, because CVD risk factors are similar in individuals with and without diabetes, benefits observed in nutrition studies in the general population are probably applicable to individuals with diabetes.
The previous section on dietary fat addresses the need to reduce intake of saturated and trans fatty acids and cholesterol.
Hypertension, which is predictive of progression of micro- as well as macrovascular complications of diabetes, can be prevented and managed with interventions including weight loss, physical activity, moderation of alcohol intake, and diets such as DASH Dietary Approaches to Stop Hypertension. The DASH diet emphasized fruits, vegetables, and low-fat dairy products; included whole grains, poultry, fish, and nuts; and was reduced in fats, red meat, sweets, and sugar-containing beverages 7 , , The effects of lifestyle interventions on hypertension appear to be additive.
Reduction in blood pressure in people with diabetes can occur with a modest amount of weight loss, although there is great variability in response 1 , 7. Regular aerobic physical activity, such as brisk walking, has an antihypertensive effect 7. Although chronic excessive alcohol intake is associated with an increased risk of hypertension, light to moderate alcohol consumption is associated with reductions in blood pressure 7.
Heart failure and peripheral vascular disease are common in individuals with diabetes, but little is known about the role of MNT in treating these complications.
Alcohol intake is discouraged in patients at high risk for heart failure. Ingestion of 15—20 g glucose is the preferred treatment for hypoglycemia, although any form of carbohydrate that contains glucose may be used. In individuals taking insulin or insulin secretagogues, changes in food intake, physical activity, and medication can contribute to the development of hypoglycemia.
The acute glycemic response correlates better with the glucose content than with the carbohydrate content of the food 1. Although pure glucose may be the preferred treatment, any form of carbohydrate that contains glucose will raise blood glucose Adding protein to carbohydrate does not affect the glycemic response and does not prevent subsequent hypoglycemia. Adding fat, however, may retard and then prolong the acute glycemic response. During hypoglycemia, gastric-emptying rates are twice as fast as during euglycemia and are similar for liquid and solid foods.
During acute illnesses, insulin and oral glucose-lowering medications should be continued. During acute illnesses, testing of plasma glucose and ketones, drinking adequate amounts of fluids, and ingesting carbohydrate are all important. Acute illnesses can lead to the development of hyperglycemia and, in individuals with type 1 diabetes, ketoacidosis. During acute illnesses, with the usual accompanying increases in counterregulatory hormones, the need for insulin and oral glucose-lowering medications continues and often is increased.
In adults, ingestion of — g carbohydrate daily 45—50 g every 3—4 h should be sufficient to prevent starvation ketosis 1. Establishing an interdisciplinary team, implementation of MNT, and timely diabetes-specific discharge planning improves the care of patients with diabetes during and after hospitalizations.
Hospitals should consider implementing a diabetes meal-planning system that provides consistency in the carbohydrate content of specific meals. Hyperglycemia in hospitalized patients is common and represents an important marker of poor clinical outcome and mortality in both patients with and without diabetes Optimizing glucose control in these patients is associated with better outcomes An interdisciplinary team is needed to integrate MNT into the overall management plan , Diabetes nutrition self-management education, although potentially initiated in the hospital, is usually best provided in an outpatient or home setting where the individual with diabetes is better able to focus on learning needs , There is no single meal planning system that is ideal for hospitalized patients.
However, it is suggested that hospitals consider implementing a consistent-carbohydrate diabetes meal-planning system , This systems uses meal plans without a specific calorie level but consistency in the carbohydrate content of meals. The carbohydrate contents of breakfast, lunch, dinner, and snacks may vary, but the day-to-day carbohydrate content of specific meals and snacks is kept constant , Special nutrition issues include liquid diets, surgical diets, catabolic illnesses, and enteral or parenteral nutrition , Liquids should not be sugar free.
Patients require carbohydrate and calories, and sugar-free liquids do not meet these nutritional needs. Care must be taken not to overfeed patients because this can exacerbate hyperglycemia. After surgery, food intake should be initiated as quickly as possible. Progression from clear liquids to full liquids to solid foods should be completed as rapidly as tolerated.
The imposition of dietary restrictions on elderly patients with diabetes in long-term care facilities is not warranted. Residents with diabetes should be served a regular menu, with consistency in the amount and timing of carbohydrate.