Effect of Low Calorie Diet and Controlled Fasting on Insulin Sensitivity and Glucose Metabolism in Obese Patients With Type 1 Diabetes Mellitus

A perspective on treating type 1 diabetes mellitus before insulin is needed

Type 1 diabetes mellitus (T1DM) is a progressive autoimmune disease that starts long before a clinical diagnosis is made. The American Diabetes Association recognizes three stages: stage 1 (normoglycaemic and positive for autoantibodies to β-cell antigens); stage 2 (asymptomatic with dysglycaemia); and stage 3, which is defined by glucose levels consistent with the definition of diabetes mellitus. This Perspective focuses on the management of the proportion of individuals with early stage 3 T1DM who do not immediately require insulin; a stage we propose should be termed stage 3a. To date, this period of non-insulin-dependent T1DM has been largely unrecognized. Importantly, it represents a window of opportunity for intervention, as remaining at this stage might delay the need for insulin by months or years. Extending the insulin-free period and/or avoiding unnecessary insulin therapy are important goals, as there is no risk of hypoglycaemia during this period and the adherence burden on patients of glycaemic monitoring and daily adjustments for diet and exercise is substantially reduced. Recognizing the pressing need for guidance on adequate management of children and adults with stage 3a T1DM, we present our perspective on the subject, which needs to be tested in formal and adequately powered clinical trials.

Assessment of dietary intake by self-report in adult patients with type 1 diabetes treated with a personal insulin pump

Introduction

Appropriate nutrition is an element affecting the metabolic control of patients with diabetes. There are only a few studies assessing the implementation of dietary recommendations in adult patients with type 1 diabetes; none of them assessed the implementation of nutritional standards. Our study aimed to assess the implementation of dietary recommendations and their relation to metabolic control in adults with T1DM treated with personal insulin pumps.

Materials and Methods

The study included 48 adult patients who were divided into two subgroups and compared, based on HbA1c above and below 6.5%. Each patient's nutrient, vitamin, and mineral intake was assessed on self-reported 3-day 24-hour surveys of food consumption. Records were introduced into the dietetic software DietaPro, (source: http://www.dietapro.eu/) which revealed nutrient content. We evaluated the percentage of patients with nutrient consumption below recommended values based on current recommendations.

Results

The studied population was characterized by insufficient consumption of most nutrients and vitamins: sodium, potassium, calcium, magnesium, iron, zinc, copper, iodine, manganese, vitamin A, vitamin D, vitamin E, thiamine, riboflavin, niacin, vitamin B6, folate, vitamin B12, vitamin C. Patients’ diet did supply correct amounts of phosphorus, and too much fatty acid and cholesterol. There were no statistically significant differences in most of the nutrient intakes across the two groups. Nevertheless, we observed a significant difference in the polyunsaturated fatty acids, sodium, niacin, and calcium intakes.

Conclusions

The studied patients consumed too much saturated fatty acid and dietary cholesterol. The consumption amounts of most nutrients and vitamins were associated with the risk of deficiency. The obtained results indicate the need for further dietary education for patients with T1DM.

The effects of diet on weight and metabolic outcomes in patients with double diabetes: A systematic review

With the global rise in obesity and the metabolic syndrome, double diabetes is increasingly prevalent in patients with type 1 diabetes. This review investigated the effects of diet on weight management and metabolic outcomes in patients with double diabetes. MEDLINE, CENTRAL, EMBASE, PsycINFO, CINAHL, ERIC, and Web of Science databases were searched through September 2020. Population- or individual-level dietary interventions, and observational studies investigating dietary patterns in adults with type 1 diabetes and overweight or obesity, were eligible for inclusion. The quality of studies was assessed. Four eligible studies were included in this review, comprising two randomized controlled trials, one pretest-posttest study, and one cross-sectional study. Study populations included between 10 and 1040 participants. Dietary interventions included the Mediterranean diet, low-fat diet, intermittent fasting, continuous energy restriction, and a combination of fasting and a standardized low-calorie diabetic diet (LCD). Significant weight loss was observed within groups for low-fat diet, Mediterranean diet, fasting, LCD with fasting, intermittent fasting, or continuous energy restriction, but there were no between-group differences. Weight maintenance was only achieved in interventions where fasting or intermittent fasting were present. Dietary interventions in published data failed to demonstrate effects on metabolic syndrome. Larger sample, high-quality trials conducted over longer periods are urgently required to determine the efficacy of diet for weight management and improving metabolic outcomes in individuals with double diabetes. This would provide much needed evidence-based guidance for dietary interventions, which are well known to be the cornerstone of clinical care.

Seven-day fasting as a multimodal complex intervention for adults with type 1 diabetes: Feasibility, benefit and safety in a controlled pilot study

OBJECTIVES

Intermittent as well as prolonged fasting are receiving considerable attention and appear favorable in conditions such as metabolic syndrome, type 2 diabetes, and rheumatic diseases. Fasting for individuals with type 1 diabetes (T1D) is generally considered too risky. However, the ability and possibility to change from carbohydrate- to ketone-based fuel supply might be relevant for individuals with T1D. The aim of this patient-led research was to investigate the feasibility, benefit, and safety of a 7-d multimodal fasting intervention in individuals with T1D.

METHODS

This was a non-randomized controlled pilot study, with 20 participants with T1D and 10 without the disease. Data acquisition took place before, after, and 4 mo after the intervention and daily during intervention.

RESULTS

Of the individuals with T1D, 19 finished fasting. A mean β-hydroxybutyrate as representative ketone body increased to 2.8 ± 1.9 mmol/L on day 7; whereas average glucose remained between 4.9 (±1.5) and 7.5 (±2.3) mmol/L (89 ± 27 and 136 ± 40 mg/dL). Mean daily insulin dose was adjusted from 24.4 (3-50) IU on the day before fasting to 7.6 (0-26.7) IU on day 7. Quality of life (WHO-5) normalized from 54 (±4.4) to 68.8 (±15; P = 0.01) after fasting. There was a decrease from before until the follow-up 4 mo later of weight from 77.6 (±20.4) to 76.6 (±20.9) kg (P = 0.023) and for body mass index from 27.68 (±7.04) to 26.74 (±7.15) kg/m² (P = 0.008). Diastolic blood pressure increased from 69.75 (±11.41) to 75.74 (±8.42) mm Hg (P = 0.028) and stayed in a healthy range on average. Fasting-related side effects were all temporary, and slightly more prevalent in those with type 1 diabetes compared with the reference group.

CONCLUSIONS

This study demonstrated the feasibility, benefits, and safety aspects of a 7-d fast in adults with T1D.

Insulin resistance in type 1 diabetes mellitus

For long the presence of insulin resistance in type 1 diabetes has been questioned. Detailed metabolic analyses revealed 12%-61% and up to 20% lower whole-body (skeletal muscle) and hepatic insulin sensitivity in type 1 diabetes, depending on the population studied. Type 1 diabetes patients feature impaired muscle adenosine triphosphate (ATP) synthesis and enhanced oxidative stress, predominantly relating to hyperglycemia. They may also exhibit abnormal fasting and postprandial glycogen metabolism in liver, while the role of hepatic energy metabolism for insulin resistance remains uncertain. Recent rodent studies point to tissue-specific differences in the mechanisms underlying insulin resistance. In non-obese diabetic mice, increased lipid availability contributes to muscle insulin resistance via diacylglycerol/protein kinase C isoforms. Furthermore, humans with type 1 diabetes respond to lifestyle modifications or metformin by 20%-60% increased whole-body insulin sensitivity, likely through improvement in both glycemic control and oxidative phosphorylation. Intensive insulin treatment and islet transplantation also increase but fail to completely restore whole-body and hepatic insulin sensitivity. In conclusion, insulin resistance is a feature of type 1 diabetes, but more controlled trials are needed to address its contribution to disease progression, which might help to optimize treatment and reduce comorbidities.