Abstract
Purpose
The element fluorine, which is never found in nature in a free state, is the source of the fluoride ion. When fluoride intake is excessive, it can cause various impairments in living organism. This review aims to assess the relationship between fluoride exposure and glucose metabolism, considering positive, negative, and null findings, with a focus on its potential role in insulin resistance and diabetes-related complications.
Methods
Numerous studies that have demonstrated changes in blood glucose and insulin variations due to fluoride are included in our analysis on the bases of their relevance. Twenty significant research papers from Pubmed, Google Scholar, and Research Gate are included up to January 2025 using search terms such as “Fluoride,” “Toxicity,” “Diabetes,” “Insulin resistance,” “fluoride and diabetes,” “fluoride and insulin,” “fluoride and blood glucose” in this review. Of the 20 research papers, 14 involve normal organisms unaffected by diabetes or complications connected to the disease, serving as standard animal models, while 5 involve animals exposed to diabetes and 1 is a human population study.
Results
The findings suggest a negative association between fluoride exposure and diabetes, as studies indicate fluoride’s potential role in impairing glucose homeostasis and increasing insulin resistance. These research studies showed how fluoride affected the participants’ blood sugar and diabetes-related complications.
Conclusion
This study highlights how important it is to comprehend how fluoride may contribute to diabetes or diabetes-related complications, and it makes recommendations for future research directions that might lead to the discovery of efficient treatment measures to avoid them.
Introduction
The element fluorine is widely distributed in the earth’s crust and interacts easily with other elements to form fluoride salts [1]. In food, water, soil, rocks, and other materials, fluoride is a prevalent environmental contaminant [2]. While fluoride can promote osteoblastic activity and proliferation, which can result in enhanced bone production, it is a necessary trace element for maintaining bone health. On the other hand, consuming too much NaF might hinder the digestion of carbohydrates, which can increase the risk of hyperglycaemia, insulin resistance, and modifications to insulin signalling [3]. In an effort to reduce the amount of F– that people are exposed to through drinking water, the WHO and a few other nations have set F– limits falling between 1 and 1.5 mg/L [4].
Section snippets
Sources of fluoride exposure
Aerosols, food, and cosmetics are some of the ways that fluoride can enter the body. Water consumption is the most common way that humans are overexposed to fluoride (F–) [5], while dietary consumption, including vegetables, cereals, and drinks produced on agricultural land, represents the second potential exposure pathway due to trace levels of F– present in these foods [6]. Since they are raised on soil, these foods easily absorb fluoride. It also relies on the F– content of the water,…
Material and methods
A thorough search was carried out employing terms like “fluoride,” “toxicity,” “diabetes,” “blood glucose,” and “insulin resistance” “fluoride and diabetes,” “fluoride and insulin,” “fluoride and blood glucose” on PubMed, Google Scholar, and Research Gate as shown in Fig. 2. Studies were selected based on their relevance on the effect of fluoride on blood glucose, insulin resistance, and related metabolic parameters in humans or animal models were considered. Key findings, research design,…
Fluoride and diabetes
Histological study has revealed that fluoride treated rats showed an increase in the insulin-positive region, which refers to areas in the pancreatic tissue stained to identify insulin-producing beta cells. However, despite the increase in the insulin-positive area, its ratio to the total pancreas or islet area decreased. This indicates that although fluoride exposure increased the insulin-positive area, it did not proportionately expand the overall pancreatic or islet structure.
Summary
Fluoride exposure has been shown to disrupt pancreatic function and glucose metabolism, potentially increasing the risk of diabetes. Animal studies indicate that fluoride alters hormonal secretion from the islets of Langerhans, reducing insulin and glucagon levels, thereby disturbing glucose homeostasis [46], [64], [65]. The severity of hyperglycemia correlates with fluoride dosage, with significant increases noted at doses nearing LD50 levels [48]. Impaired glucose tolerance is prevalent in…
Conclusion
Fluoride exposure leads to pancreatic damage causes oxidative stress, increases inflammatory genes (TNF-a and IL-6), decreases anti-inflammatory genes (IL-10), and alters the architecture of the islets of Langerhans. It also affects the glucose regulation in the body. Similar to the process seen in diabetes, it also suppresses the production of insulin and glucagon, causes insulin resistance, raises blood glucose levels, and reduces glucose tolerance in a dose-dependent way. …
Abbreviations
AMP, Adenosine monophosphate; b.w., Body weight; BUN, Blood Urea Nitrogen; CAT, catalase; dL, decilitre; F, Fluoride; g, gram; HOMA-IR, Homeostatic Model of Assessment of Insulin Resistance; IL-6, Interleukin-6; HDL, high-density lipoprotein; GI, glycaemic index; GPx, glutathione peroxidase; kg, kilogram; LD, Lethal Dose; l, litre; mg, milligram; ml, millilitre; mM, millimolar; mol, mole; mRNA, messenger ribonucleic acid; MDA, malondialdehyde; N.A., Not applicable; NaF, Sodium Fluoride; ng,
Funding sources
This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors.
Declaration of Competing Interest
The author declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.
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