Changing eating habits is an important pillar in the prevention and treatment of type 2 diabetes. But what exactly can be recommended to patients to positively impact blood sugar levels and lipid parameters, and to prevent acute and chronic diabetes complications? A review summarizes the data available on this topic.
The worldwide increase in type 2 diabetes is mainly attributed to lifestyles that develop into overweight and obesity more easily. Reducing body weight or maintaining normal weight therefore plays a major role in the prevention of type 2 diabetes, and weight loss turns into an important part of diabetes management for most patients.
Omorogieva Ovo from the University of Greenwich in London, UK, provides an overview of what might be useful beyond calorie restriction for specific dietary recommendations (including strategies such as micro-nutrient supplements) in type 2 diabetes.
In many cases, combinations of vitamins and trace elements are offered especially for people with diabetes. The connection of type 2 diabetes with vitamin D and calcium has been relatively well investigated. Several observational studies have shown an association between high dairy product consumption and a lower risk of type 2 diabetes, although the possible mechanism of action of calcium on diabetes prevention is still unclear.
In addition to regulating bone metabolism, vitamin D also plays an important role in glucose homeostasis. In younger Mexican women (20 to 49 years), in whom vitamin D deficiency is widespread, vitamin D deficiency has been associated with obesity, type 2 diabetes and elevated total cholesterol levels. More information on the possible influence of these levels and its action mechanism is hoped to be obtained from randomized trials.
Zinc is also one of the possible candidates that could have a protective effect on type 2 diabetes. In a systematic review with meta-analysis, it was observed that a high-zinc nutritional intake could reduce the risk of type 2 diabetes. However, elevated serum zinc levels appear to increase the risk, so the significance remains unclear - especially since no correlation between zinc supplementation and the incidence of type 2 diabetes was found. The influence of the supply of zinc, potassium, calcium and magnesium on blood sugar control in type 2 diabetes was also investigated. The supply of these micro-nutrients was often sub-optimal in the affected individuals and low intake was associated with higher HbA1C levels and triglyceride levels.
What about the macro-nutrients? The focus here is mainly on a carbohydrate restriction. For a low carbohydrate diet (LCD), in which a part of the basic food is replaced by nuts, it has been proven that it not only leads to weight loss, but also has a positive effect on glucose and lipid levels. In another randomized controlled trial, the question was investigated as to whether the expensive tree nuts such as almonds can be replaced by significantly cheaper peanuts. In both groups, fasting blood glucose and postprandial blood glucose values decreased equally and after three months there was no significant difference in HbA1C between the two groups.
A review from Japan compared a calorie- and carbohydrate-reduced diet in patients with type 2 diabetes. Here too, carbohydrate reduction proved to be superior in terms of blood glucose control, at least in the short term.
Another focus of nutritional medicine for diabetes is polyunsaturated fatty acids (PUFAs). According to prospective observational studies, a high consumption of saturated fatty acids seems to increase the risk of type 2 diabetes, a high consumption of PUFAs seems to decrease it. However, only about half of the controlled studies that examined the influence of fish, fish oil, vegetable oils and nuts on blood sugar control in diabetics showed a positive result. So there is still a lot of research to be done, writes the author.
It is undisputed that food with a low glycaemic index (GI) has a positive effect on HbA1C and fasting blood glucose levels. Triglyceride and interleukin-6 levels are also favorably influenced, while cholesterol levels do not change significantly.
At least in animal models, various plant extracts have also shown positive effects on glucose and lipid metabolism in type 2 diabetes. Potential candidates include white ginger lily (Hedychium coronarium), rosemary extract, fermented tempeh and a combination of freeze-dried aronia (chokeberry), red ginseng and UV-treated shiitake mushrooms.
Source:
Omorogieva Ojo; Diatary Intake and Type 2 Diabetes; Nutriens (2019); 11, 2177;
Doi: https://doi.org/10.3390/nu11092177
https://www.mdpi.com/2072-6643/11/9/2177/htm