During this 8-week study, β-cell function was tested by a gold standard method that used a stepped glucose infusion with subsequent arginine bolus (21). In type 2 diabetes, the glucose-induced initial rapid peak of insulin secretion (the first phase insulin response) typically is absent. This was confirmed at baseline in the study, but the first phase response increased gradually over 8 weeks of a very-low-calorie diet to become indistinguishable from that of age- and weight-matched nondiabetic control subjects. The maximum insulin response, as elicited by arginine bolus during hyperglycemia, also normalized. Pancreas fat content decreased gradually during the study period to become the same as that in the control group, a time course matching that of the increase in both first phase and total insulin secretion (Fig. 3). Fat content in the islets was not directly measured, although it is known that islets take up fat avidly (24) and that islet fat content closely reflects total pancreatic fat content in animal models (25). Although a cause-and-effect relationship between raised intraorgan fat levels and metabolic effect has not yet been proven, the time course data following the dietary intervention study are highly suggestive of a causal link (21).
Whole-body insulin resistance is the earliest predictor of type 2 diabetes onset, and this mainly reflects muscle insulin resistance (26). However, careful separation of the contributions of muscle and liver have shown that early improvement in control of fasting plasma glucose level is associated only with improvement in liver insulin sensitivity (20,21). It is clear that the resumption of normal or near-normal diurnal blood glucose control does not require improvement in muscle insulin sensitivity. Although this finding may at first appear surprising, it is supported by a wide range of earlier observations. Mice totally lacking in skeletal muscle insulin receptors do not develop diabetes (27). Humans who have the PPP1R3A genetic variant of muscle glycogen synthase cannot store glycogen in muscle after meals but are not necessarily hyperglycemic (28). Many normoglycemic individuals maintain normal blood glucose levels with a degree of muscle insulin resistance identical to those with type 2 diabetes (29).
If a drug treatment’s efficacy is questionable, the adverse event and safety profile is even more important. As a popular food additive, cinnamon seems safe when consumed at doses of a few grams per day. (1 teaspoon of the powder is about 4.75 grams).  While the trials have been small and short in duration, no significant adverse events have been reported. It is Generally Recognised as Safe (GRAS), as a seasoning and flavoring. However, reversible liver damage has been reported with therapeutic use, due to coumarin, a chemical also present in Cassia cinnamon. Those with liver impairment or dysfunction may be at greater risk of harm. There are no published long-term studies with cinnamon that inform us whether chronic consumption of high doses is safe.
Evidence linking hepatic insulin sensitivity to intraorgan triglyceride content has been steadily accumulating. In insulin-treated type 2 diabetes, insulin dose correlates with the extent of fatty liver (35), and in turn, this is associated with insulin sensitivity to suppression of hepatic glucose production (36). Decreasing the fat content of liver is associated with improvement in insulin suppression of glucose production and, thereby, with improvement in fasting plasma glucose (20,23).
Following these five principles can significantly influence blood glucose levels. However, not everyone responds the same. Some people with have immediate low blood glucose levels. Others may experience a slow and steady improvement of glucose control. Some may have temporary high glucose levels. Our experience is that this is transient and most people will improve.
Given the consequences of diabetes, self-management is something I want to encourage, not discourage. Without a commitment from the patient to take an active role in managing their diabetes, any treatment plan is doomed to fail. So is self-treatment with supplements a wise idea?  There’s an array available, and patients regularly ask about the latest treatment “Big Pharma doesn’t want you to know about”. That treatment used to be chromium. Ginseng was popular for a time, too. Fenugreek and bitter melon are used as well. The treatment that seems most popular now is cinnamon. Like any other herbal remedy, most sources will tell you that it’s been used for “thousands of years” as a medicinal herb. As a treatment for diabetes, I have my doubts. While reports of diabetes go back to 1552 BCE, the ability to effectively measure any diabetes treatment only goes back a few decades. Interest in cinnamon as a treatment seems to have started with in vitro tests but gained some plausibility in 2003, when a study from Alam Khan suggested several grams of cassia cinnamon per day could lower fasting blood glucose. Khan randomized Type 2 diabetes to 1g, 3g, or 6g of cinnamon for 40 days. All three groups improved their fasting blood glucose, and blood lipid levels, but there was no effect on A1C.
There is no prescribed diet plan for diabetes and no single “diabetes diet”. Eating plans are tailored to fit each individual's needs, schedules, and eating habits. Each diabetes diet plan must be balanced with the intake of insulin and other diabetes medications. In general, the principles of a healthy diabetes diet are the same for everyone. Consumption of various foods in a healthy diet includes whole grains, fruits, non-fat dairy products, beans, lean meats, vegetarian substitutes, poultry, or fish.