Carbohydrates and Diabetes Management

Extract from Prof Feinman et al.

DIETARY CARBOHYDRATE RESTRICTION AS THE FIRST APPROACH TO DIABETES MANAGEMENT
Discussion
The need for a reappraisal of dietary recommendations stems from the following:
1. General failure to halt the epidemic of diabetes under current guidelines.

2. The specific failure of low-fat diets to improve obesity, cardiovascular risk, or general health (points 1 and 4).

3. Constant reports of side effects of commonly prescribed diabetic medications, some quite serious (points 12).

4. Most importantly, the continued success of low-carbohydrate diets to meet the challenges of improvement in the features of diabetes and metabolic syndrome in the absence of side effects.

The benefits of carbohydrate restriction are immediate and well documented. Concerns about the efficacy and safety of carbohydrate restriction are long term and conjectural rather than data driven.
It is well established that weight loss, by any method, is beneficial for individuals with diabetes. The advantages to a low-carbohydrate approach are that, because of greater satiety, explicit calorie reduction on the part of the patient may not be required. There may be de facto reduction in calories without the need for replacement. The extent to which there is replacement, either fat or protein may be beneficial (points 4 and 6) although, in practice, fat is recommended unless there is already lower protein. Concerns about high protein in carbohydrate restriction have been raised but, except for those people with existing kidney disease, none has ever been demonstrated [91]. Protein also tends to a stable self-limiting part of the diet. Perhaps most important, if carbohydrate is low, glycemic control and other physiologic parameters are improved even if weight loss is not accomplished (point 3).
Finally, it should be recognized that the use of low-carbohydrate diets is not a recent experiment and may well approximate the diet used by much of humanity for tens of thousands of years before the rise of agriculture. Current knowledge dictates that carbohydrate restriction should be a default treatment for type 2 diabetes and a default adjunct therapy for type 1. Given the superior outcomes of carbohydrate-restricted diets, patients should not be discouraged from adhering to them as is frequently observed. They should, in fact, be encouraged to follow this approach.
The 12 points of evidence represent the best investigated and least conjectural ideas on diabetes. It is unlikely that one dietary strategy, any more than one kind of pharmacologic treatment will be best for all individuals. Patients can refuse medication or opt out of surgery, but they cannot not be on a diet and low-carbohydrate is the reasonable place to start. We recognize that there are many complications and issues that are still not understood, however, we have tried to isolate the factors that have the fewest contradictions.
This review emphasized the most obvious principles. An anonymous reviewer, however, raised two important if more conjectural points. We were asked “To specify role of starch versus mono- and disaccharides in carbohydrate-semi-restricted diet (optimal proportions).” and “In discussion to draw more attention to the possible disadvantages of low-carbohydrate diet in people with diabetes.”
Role of starch versus mono- and disaccharides
Replacement of carbohydrate with fat or, in some cases, with protein, is beneficial in both types of diabetes leading to better glycemic control, weight loss, cardiovascular risk markers, and reduction in medication. This is what we know. That is what is established in well-controlled experiments in individuals with diabetes (points 1, 3, and 10). The evidence does not contain strong data on which carbohydrates should be removed (or even what the effect of different fats of protein might be). On first principle, glucose is of greatest importance in diabetes. The sudden interest in fructose and sucrose as unique types of carbohydrate has made the discussion quite controversial. Both the scientific[92] and [93] and popular literature [94] have been unrestrained in attributing harm to fructose. Generally, fructose is known to have unique effects compared with glucose, although most of these are seen on a high-carbohydrate diet [95] and there may be little difference as carbohydrate is lowered. It is likely that on a low-carbohydrate diet, most fructose that is consumed will be converted to glucose. We have provided a perspective on the metabolism of fructose [96] where we emphasize its integration into general carbohydrate metabolism. The fact that up to 60% of ingested fructose can be converted to glucose makes the analysis of which sugar does what very difficult.
The definitive experiment, testing whether removing fructose is preferable to removing glucose in the implementation of a low-carbohydrate diet has never been performed. This is presumably due to the poor acceptance of low-carbohydrate diets in general [4]. One study showed that glycemic response was lower after ingestion of a low-starch meal with 43% total carbohydrate and high levels of fruit compared with a high-starch, high-carbohydrate meal or a 40% carbohydrate “typical American meal” [97]. There was also, as expected, a lower 24-h integrated serum insulin response. The results demonstrate the value of specifically removing starch, although it was not determined whether removing sugar would be equally effective or better. As above, this group has also shown good results simply by reducing glucose (point 3).
Because of the limited insulin effect, it was once thought that fructose might be an acceptable source of carbohydrate, but this turned out to be questionable and may actually have a deleterious effects if administered intravenously alone. Analysis of the hepatic metabolism shows that the liver expects the two sugars to appear together [96], fructose (e.g., increases glucokinase activity).
The reviewer's original question is framed in terms of “carbohydrate-semi-restricted diet (optimal proportions).” It is unlikely that there is a general answer. As a guide for the patient with diabetes, the prescription of many agencies to “eat to the meter” seems like a good one.
Possible disadvantages of low-carbohydrate diet in people with diabetes
To assess the disadvantages of carbohydrate restriction for individuals with diabetes, one has to ask what the standard is and where it came from. The idea that there is an effective diet of known macronutrient composition, one tested in long-term, or even short-term trials, that is beneficial in treating diabetes is implied by the question. To our knowledge, no such diet exists. The more dietary carbohydrate, the more medication will be required (point 11). The disadvantage to a low-carbohydrate diet, as in any intervention, will rest with individual choices. Low-carbohydrate diets generally have better compliance (point 5) but individuals vary in tastes and assessment of risk–benefit perceptions.
The flipside of the benefit from reduced medication (point 11) presents a real potential disadvantage. Because of the effectiveness of carbohydrate restriction on glycemic control, there is a danger of hypoglycemia for those patients on glucose-lowering medication. It is recommended that medication be reduced in advance of initiating a low-carbohydrate diet. Personal communications suggest that there are a variety of strategies for reducing insulin or other drugs. Whether the patient (or the physician) knows this is potentially serious question. Instructions for the study in reference [80], for example, provide the following guide:
“Metformin was continued for the duration of the study unless the participant or his/her doctor requested it be lowered, at which point the dose was cut in half or discontinued completely. Sulfonylurea doses were reduced in half if the entry HbA1c was <7.5% or discontinued if the participant was on a minimum dose. Sulfonylurea was discontinued if predinner glucose levels went below 110 mg/dL despite prior dose reduction; thiazolidinediones were continued for participants with starting with a HbA1 c above 7% and discontinued for those with starting HbA1 c below 7%.”
Conclusion and recommendations
What evidence would be required to change the current recommendations for dietary treatment in diabetes? Evidence-based medicine tends to emphasize RCTs as a gold standard. Such absolute requirements, however, are unknown in any scientific discipline. As in a court of law, science admits whatever evidence is relevant [98]. Following the legal analogy, one has to ask: Who decides on the admissibility of the evidence? The parody by Smith and Pell [99] has been described as both funny and profound in illustrating how there is not a single type of experiment that fits every scientific question. Given the current state of research funding and the palpable bias against low-carbohydrate approaches [4], it is unlikely that an RCT can be performed that will satisfy everybody. The seriousness of diabetes suggests that we have enough evidence of different types to re-evaluate our current recommendations for treatment.

Re: Carbohydrates and Diabetes Management

So....what point are you making Dobra ?
I have been type2 diabetic for the last 10 years, I am fit and relatively healthy, I am not overweight and eat a very healthy diet which includes carbs, I am taking three different medications to control my blood sugar.

Re: Carbohydrates and Diabetes Management

I have to agree with Malcolm. What's the point of that very long article telling things that we already know.
Also as a borderline diabetic, and just on Metformin, I also try to eat healthy.
When I was told that I was borderline diabetic, I lost 1 stone very quickly by changing my eating habits.

Re: Carbohydrates and Diabetes Management

My Dad was diagnosed with type 1 diabetes in 1928.
He was one of the first people to be given insulin.

He was taken into hospital and for the first week was given nothing to eat but boiled cabbage and cabbage water to 'cleanse his system' (he was starving and gave the man in the next bed 6d for the fat he left on the side of his plate). After that he manage his condition with the help of daily injections of insulin and a good diet.
He lived to the age of 89.

One think he didn't eat was sugar but he did eat carbohydrates in the form of bread/potatoes/ porridge/even scones without sugar. He didn't drink alcohol except a drink at Christmas.
He ate meat/vegetables/ fruit (not plums which were not allowed at the time) and porridge oats every day .

He was always on the lean side and rarely ill so must have been doing something right.

Re: Carbohydrates and Diabetes Management

Well I feel I take enough medications already so when I was diagnosed type 2 I refused medication and asked for 6 months to try and get it right myself, 2 months later I had it under control and 3 years later they no longer list me as diabetic and I did it all with low carb no sugar diet.

I do have carbs now but my porridge this morning will be only carbs I have today, I just limit them a little these days. I can even eat cake if I just have one slice and not the entire thing

Re: Carbohydrates and Diabetes Management

I am also Diabetic Type I and have been for 27 years, and have no problems, I eat a healthy diet and eat a small amount of Carbs and test my blood 6 times a day.

Re: Carbohydrates and Diabetes Management

I was diagnosed earlier this year as borderline or prediabetic and advised to limit my carbs to 140g a day. This I did and have lost over a stone in weight. I've not been back for another blood test yet but am hoping to have reversed the condition.

Re: Carbohydrates and Diabetes Management

I don't check my blood very often, but when I do it is normal.
I had a blood test a couple of weeks ago and I have not had a phone call from the surgery, so I expect all is well.
As for carbs, I do eat a few such as potatoes, bread, and pasta.
Also the occasional piece of cake.
No sugar just sweeteners.

Re: Carbohydrates and Diabetes Management

We need some carbs to keep healthy. I wish I could cut out sugar in drinks, although I've cut down I just don't enjoy tea or coffee without and don't like the taste of sweeteners.

Re: Carbohydrates and Diabetes Management

There are different makes of sweeteners, and I find that they taste different.
You could try some and maybe you can find one that suits.