A Scoping Review of Glucose Spikes in People Without Diabetes: Comparing Insights from Grey Literature and Medical Research.

Background: The use of continuous glucose monitoring (CGM) has grown, extending its use to people without diabetes. CGM helps prevent hyperglycaemia-related complications in diabetes, however, its value in people without diabetes remains uncertain. Despite online sources framing glucose spikes as harmful, studies show that overall, most healthy individuals maintain normal glucose levels - therefore questioning the significance of these spikes. This project aims to examine whether glucose spikes affect the health of people without diabetes. By comparing the medical and grey literature, we aim to determine whether the grey literature aligns with the peer-reviewed medical literature, or whether it could cause harm through misinformation. Methods: Population: people without diabetes and human endothelial cells; Concept: the effect of glucose spikes on health; Context: global studies and grey literature. Following the PRISMA-ScR guidelines, a systematic search was undertaken via Medline, Embase and Proquest. Fifty-nine sources were reviewed - 11 medical research papers and 48 grey literature sources. Excel spreadsheets were developed and piloted for the medical and grey literature respectively. Data was extracted and charted, and a narrative synthesis was formulated. Results: Both the medical and grey literature reported glucose spikes can cause endothelial dysfunction, oxidative stress and inflammation in people without diabetes or human endothelial cells. However, the grey literature reported additional effects that is, increased risk of cancer and effects on mental health, energy, mood and sleep. Conclusions: Glucose spikes may impact the health of people without diabetes, but significant health outcomes likely stem from long-term frequent spikes rather than isolated acute spikes. Discrepancies between the medical and grey literature highlight potential for misinformation in the grey literature, although the author does not claim cited sources are misleading, nor does the absence of claims in medical literature mean grey literature is misinforming. Further research is needed to verify if grey literature claims align with peer-reviewed evidence, as hypothetically, misinformation could significantly impact consumer wellbeing.