*Mitigating Diabetic Foot Ulcers: The Effect of Diet and Microbiome DOI: http://dx.doi.org/10.5772/intechopen.106629*

starches (white and sweet potatoes, corn, peas, squash, and turnips). However, many of these foods contain many necessary nutrients and cannot necessarily be completely excluded. Most vegetables including potatoes contain vital amounts of fiber that essential bacteria that are part of the microbiota require.

Fiber is also an essential part of the diet and consists of starches that are nondigestible or less digestible than other forms of carbohydrates. In humans, cellulose and chitin are not digested like they are in ruminants such as cattle or other multistomach animals that consume grass or other plants. In humans, amylose even though it is a straight chain of glucose residues, and its secondary structure makes it more difficult to digest those other forms such as amylopectin that is found in plants and glycogen that is found in animals. Therefore, amylose is often considered a resistant starch, and foods that contain more amylose, and less amylopectin are considered low glycemic and will not cause glucose levels to rise as quickly or as much and can be a benefit for diabetic patients [31, 32]. Potatoes are already being developed to contain a higher amylose/amylopectin ratio by hybridizing with other strains while at the same time increasing their protein and amino acid content [31]. Not all of these new plants are commercially available as yet and potatoes such as huckleberry gold although available are more expensive than the more common commercially available varieties. Although these potatoes have been reported to have higher amylose/amylopectin ratios, it still remains to be seen if the cooking methods will have an effect and if the varieties will taste good enough to be accepted as substitutes. Until then, the recommended foods include Grains, beans (canned baked beans tend to have sugars added), rice, pasta, and starchy vegetables are actually recommended because of their high fiber content even though they may not be low glycemic.

In addition, it is rapidly becoming more important to consume vegetables because of their high polyphenol content as well. Polyphenols are a large group of plant metabolites that have many medicinal properties including antidiabetic effects. Polyphenols have been shown to decrease blood glucose levels and increase insulin secretion and sensitivity [33, 34].

The release of digested carbohydrates releases glucose that is absorbed which can raise blood glucose levels. Proteins and fats have not been found to affect diabetic patients, but any weight gain can contribute to diabetes and insulin resistance. Type one diabetes does not typically cause insulin resistance, but some type one diabetic patients have become overweight, and more than a third now have an increased risk of chronic kidney disease [35]. It has been shown that the increased blood glucose levels damage the delicate blood vessels, and many develop high blood pressure as well which can damage the vessels as well [30], which could contribute to insulin resistance. Since there is no one diet fits all, the current diet for a particular individual depends on age, weight, and the activity of the individual. It is suggested that a registered dietician may be the best way to design a diet. Typically, an individual should not consume more than 2000 calories per day, and no more than half should be from carbohydrates. Typically, also one gram of carbohydrates has about 4 calories, but these are only estimates. There are general guidelines for patients with diabetes. Watching portion size and calories are recommended for any diabetes diet. Reducing the intake of fried foods, sweets, salts and fats is a part of any diabetes diet. In some cases, even eating less more often can stabilize your glucose levels in the blood. One thing however to keep in mind is that not all calories are the same. Calories coming from energy-dense diets will predispose individuals to weight gain irrespective of the nutrient content of the food consumed [36, 37].

### **3.1 The ketogenic diet**

The most popular of diabetes-related diets are the ketogenic diet. Ketogenic diets are frequently higher fat, lower fiber diets that have lower carbohydrates making it easier to control diabetes and induce weight loss [37–39]. Low fiber diets, however, will not restore normal microbiota which contributes to obesity therefore it is not a long-term solution that should be discontinued once the normal weight is achieved. There are different forms of these diets but essentially even less carbohydrate is consumed in favor of additional protein. This is known as nutritional ketosis which is a normal biological process that may in fact reduce weight and eventually be beneficial to the individual [37, 38]. But it would only be normal when the diabetes is under control and blood glucose levels are normal. However, this is different than ketoacidosis which can occur in diabetic patients where the diabetes is not under control when insulin levels are too low, and glucose cannot be absorbed into cells instead the body uses fats for fuel. In this case, there is a sharp unhealthy rise in ketones in the blood which in turn causes the blood to become more acidic [38]. This condition can be fatal if not treated. Keto diets as well can lead to nutrient deficiencies in calcium, magnesium, vitamin D, and folic acid. The vast majority of TTDM patients are obese and only when their obesity is also under control and reduced will their diabetes symptoms disappear [37, 38]. Nevertheless, long-term use of the ketogenic diet has not been well studied and can have serious side effects. It has been shown that this diet while preventing some cancers can cause renal cancer and tumor growth in integument and other epithelial tissues [38, 40]. Ketogenic diets are often high in fat and low in fiber. That kind of diet will cause LDL levels to rise to lead to serious heart and cardiovascular diseases such as atherosclerosis. If the fats are reduced in favor of higher protein levels that can lead to serious kidney diseases and kidney stones [37].

Type one diabetes and TTDM patients can both benefit from a ketogenic diet, but the endpoints will be different. For TTDM patients, a ketogenic diet could restore normal weight and therefore usually relieve the symptoms of diabetes. For type one, the risk of ketoacidosis is significantly higher and so needs more careful monitoring. The Ketogenic diet can benefit diabetic patients because it reduces the glucose levels in the blood, lowers blood pressure, and can contribute to weight loss [37, 39].
