Diabetes

Low carbohydrate diets shown to reverse type 2 diabetes?
Westman and colleagues reported in the Journal of Nutrition and Metabolism in December 2008 that a low carbohydrate diet averaging about 50g/day and energy intake of 1500 calories/day resulted in 95% of the 48 participants with diabetes to either reduce or eliminate their diabetes medications after 6 months compared with only 62% of 49 participants in the higher carbohydrate (150g) but low GI diet also providing around 1400 calories/day. To put this in perspective, most people consume on average 250g/day carbohydrates (however alot of this may be from sugar dense foods!) so 50g/day is a severe reduction (e.g 1 slice of bread or fruit has 15g carbohydrate). This is an interesting study but one would have to double or triple their usual intake of vegetables (as they did in this sudy to 3 cups non strachy vegetables/day) to make up for the lack of cereal fibre and other nutrients - which could be seen as a positive outcome by some. Furthermore, the diet would become high in protein and fat: participants in this study were allowed to eat unlimited amounts of meat/fish/chicken/eggs, 120g yellow cheese/day, 60g cottage cheese/day resulting in protein intakes of around 110g/day (prior to diet intake was around 80g/day) and fat intake increased to 100g/day (from 88g/day) much of it coming from animal foods. In contrast, the higher carbohydrate diet provided about 50% less protein (67g/day) and fat (55g/day). The low carbohydrate diet resulted in significantly greater weight loss at 6 months (11kg) than the higher carbohydrate diet (7kg) and also greater improvements in blood sugars, blood fats (especially triglycerides) and blood pressure.

There may be a place for short term low carbohydrate diets for patients with diabetes who are at high risk of cardiovascular complications or for very motivated patients keen to reduce their medication/insulin dose, but should be undertaken under the supervision of a doctor and dietitian.
Otherwise, low carbohydrate diets are too difficult to maintain in the long term and the safety of avoiding cereal grains and fruit (even in the face of increased vegetable intake) and increased protein/fat intakes are unknown in the long term. Maybe the best advice for people with diabetes is to follow a diet some where in between these two diets i.e avoid processed sugar dense foods and fatty animal foods but include several serves daily of wholegrains and fruit, and other healthy carbohydrate containing foods like yoghurt (for the good bacteria) and legumes - which can help reduce meat intake (and hopefully mortality!) by replacing meat based meals several times a week.

Further reading: Debra Manzella from About.com http://diabetes.about.com/od/nutrition/qt/locarbdiabetes.htm

ABC HEALTH REPORT - The latest in Diabetes Research from the Baker Institute 2006
Advanced Glycation End Products or AGEs. These are formed when excess glucose in the blood reacts with protein forming byproducts that have been linked to diabetes complications like kidney disease, blindness, amputation and heart disease. However, it is also possible to consume AGEs from foods that have been cooked at high temperatures (grilled,roasted,fried foods), fermented foods (soy sauce), coffee and caramelised/browned foods (cola drinks). Having a high intake of AGEs could potentially increase one's risk of developing diabetes-like complications even in the absence of diabetes (especially in people with reduced liver or kidney function). Eating more raw/boiled/casseroled foods and less grilled/fried foods will reduce your intake of AGEs.

New Nutrition Guidelines for Diabetes

The American Diabetes Association issued new nutrition guidelines for the treatment and prevention of diabetes and its complications in January 2002.

Full report (50 pages): http://care.diabetesjournals.org/cgi/content/full/25/1/148
Summary (10 pages) : http://care.diabetesjournals.org/cgi/content/full/25/1/202

New evidence regarding magnesium and diabetes more....

Preventing Diabetes complications

Diabetes complications include an increased risk of developing heart disease, hypertension, kidney disease, and neuropathy. Controlling blood sugar levels reduces the risk of developing such complications.

The new guidelines outline strategies for controlling blood sugar levels, for example they state that:

carbohydrate from whole grains, fruits, vegetables, and low-fat milk should be included in a healthy diet

the total amount of carbohydrate is just as important as the source or type i.e improve the quality of carbohydrates consumed (prefer wholegrains) and keep portions small

the glycemic index may reduce post-meal blood glucose, but studies do not show sufficient evidence of long-term benefit for it to be recommended (for example, even though pasta has a low glycaemic index it is not advisable for people with diabetes or impaired glucose tolerance to have a large serve because the total amount of carbohydrate will be too high)

fructose is not recommended as a replacement for sucrose, even though it produces a smaller effect on blood sugar than sucrose, because fructose may adversely affect blood lipids. But, there is no evidence of this problem for naturally occurring fruit sugar.

sucrose need not be restricted by diabetics, but total carbohydrate should not increase if sugar is added (sucrose does not increase glycaemia more than equal calories from starch)

nonnutritive sweeteners are safe (saccharin, aspartame, acesulfame K, sucralose) and can be consumed by all to acceptable limits established by the U.S. Food and Drug Administration.

to help keep blood lipids in the healthy range, the primary dietary fat goal for people with diabetes is to limit saturated fat to <10% of energy intake (i.e <20g per day) and if blood cholesterol levels are high intake should be reduced to <7% of energy intake. Dietary cholesterol also needs to be kept below 300mg per day and less than 200mg is receommended if blood cholesterol levels are high. Persons with diabetes appear to be more sensitive to dietary cholesterol than the general public.

the use of monounsaturated fats as partial replacement for carbohydrates within the diet, has been shown to improve blood sugar and lipid levels. It is recommended that up to 60% of energy comes from a combination of carbohydrate and monounsaturated fat.

there is no evidence to suggest protein intake should be modified if kidney function is normal.

reduced energy intake and modest weight loss improve insulin resistance and blood sugar levels.

routine supplementation with antioxidants is not advised.

increase physical activity levels

Preventing diabetes

The guidelines recommend the following for preventing diabetes, especially if there is a family history of the disorder:

increase physical activity - all types, and it does not have to be strenuous to be beneficial
weight loss, especially from the abdomen
reduce fat intake, especially saturated fat, irrespective of weight
increase fibre intake, especially from vegetables and fruits

Limitations of these recommendations

The fifty-one scientific statements made were ranked based on how much supporting evidence there was: 16 had an A rating because of evidence from multiple, well-conducted studies, 17 received a B, 3 got a C, and 15 an E representing recommendations based on expert opinion. This shows that about one-third of the recommendations are not necessarily based on strong evidence.

See also: Glycemic index

Last Updated: March, 2009.