A Review: Are Some Diet Models Beneficial or Harmful for Type II Diabetes Mellitus?

Diabetes mellitus (DM) is a chronic disease affecting millions worldwide. According to the current literature, type II DM is linked with some currently trending diet models such as high-protein, low-carbohydrate (CHO), ketogenic, gluten-free (GF), intermittent fasting (IF) nutrition models, the Mediterranean diet (MD), etc. The purpose of this review article was to shed light on the relationships between some currently trending diet models and type II DM, their potential effect mechanisms and any complications according to evidence from the current literature. High-protein, low-CHO, ketogenic, GF and IF nutrition models can potentially decrease inflammation and body weight, improve the lipid profile and gut microbiota, increase the secretion of incretin hormones and regulate immune responses and thus increase insulin sensitivity in tissues. However, these currently trending diet models may result in acute or chronic complications such as; hypoglycemia, fatigue, lethargy, nutrient deficiencies, acute abnormalities or other related chronic disorders. Some of these complications may be critical for life. Conversely, the MD has very important beneficial effects on the prevention of type II DM and there is no evidence in the literature which shows this diet model has any side effects. In conclusion, applying optimal nutritional principles is the most recommended nutritional approach in order to reduce risk and manage type II DM.