The Short and Long-term Effects of Low Advanced Glycation End Product* Diet (AGE)

The aim of this study was to examine the hypothesis that a diet low in advanced glycation end products (AGE) would provide short and long term improvement in metabolic and inflammatory parameters and serum AGE, Srage, carboxymethyllysine (CML) and methylglyoxal (MG) values in individuals with type 2 diabetes. Specifically, in order to observe the effect of AGE content on the results, diabetic patients who are followed up and who know the principles of low glycaemic index and glycaemic load nutrition suitable for diabetic patients, who do not have additional diseases and who do not smoke were selected. In recent years, it has been determined that AGE accumulation in the tissue has an effect on the pathophysiology of many diseases such as Alzheimer's disease as well as chronic complications of diabetes. However, the contribution of dietary AGE intake to this pool is controversial. There are studies with conflicting results in the literature on whether a low AGE diet is effective on metabolic and biochemical well-being. In addition, studies investigating the effects of reducing AGE content in the diet of people with no chronic disease are limited. In this study, the metabolic results of dietary modification in the short term of 2 weeks and in the long term of 3 months are determined. In addition, the results are analysed separately in type 2 diabetic and non-diabetic groups. Thus, the data showing the short and long term metabolic effects of dietary AGE levels for diabetic and non-diabetic patients will contribute to the literature.

The study included 30 volunteers with type 2 diabetes and 30 healthy participants. During the initial interviews, participants were provided with training on low AGE (advanced glycation end-products) dietary principles. In the same session, measurements were taken and recorded for height, body weight, blood pressure, waist and hip circumference, and body fat percentage. Fasting blood glucose, HbA1c, c-peptide, C reactive protein (CRP), insulin, blood lipid levels, 1-5 anhydroglucitol (1-5 AG), AGE, Soluble AGE Receptor (sRAGE) , methylglyoxal (MG) and carboxymethyllysine (CML) levels were measured through blood samples. Participants were asked to maintain a dietary journal and were followed up through weekly online or face-to-face meetings. They were called in for a follow-up examination 2 weeks and 3 months after the initial interview. Anthropometric measurements and blood tests were repeated. After the completion of a 3-month follow-up for all participants, measurements from both the short and long term resulting from the low AGE diet were analyzed by comparing them to the initial measurements, both for participants with and without diabetes.

Participants were divided into ten-person groups. Each group was individually invited for a face-to-face meeting where they were provided with a 50-minute low-AGE diet education prepared in accordance with the recommendations of the American Diabetes Association and the Turkish Society of Endocrinology and Metabolism. During the first 20 minutes of the education, a PowerPoint presentation highlighted the importance of choosing plant-based, low-AGE foods and emphasized cooking methods such as boiling, steaming, and preparing meals with added liquids. Participants were advised against frying, roasting, and grilling. Additionally, information was provided on marinade techniques and the use of spices or ingredients such as lemon or vinegar to lower pH in meals. Following the education, participants were given a dietary diary to record their food intake and were asked to self-assess their diet adherence on a scale of 1 to 10 on a weekly basis.

Inclusion Criteria: To have the competence to adhere to dietary recommendations Exclusion Criteria: Being <18 years old or >65 years old Having a history of serious cardiovascular diseases (atrial fibrillation, stroke, ischemic heart disease, peripheral vascular disease, heart failure) Having chronic obstructive pulmonary disease Smoking Having kidney or liver failure Having a chronic gastrointestinal disease associated with malabsorption or chronic pancreatitis Having a history of rheumatological disease Having a history of severe acute illness, malignancy, or alcohol abuse in the last 1 month Receiving immunosuppressive treatment