From the Guidelines
Fluoride exposure has been associated with neurotoxic effects, particularly in children, and its use should be carefully considered to minimize potential risks. The espen micronutrient guideline 1 suggests that fluoride can be safely provided in enteral nutrition (EN) at doses of up to 3 mg/day, but its addition to parenteral nutrition (PN) is debated. While fluoridation of drinking water has been shown to prevent tooth decay by 26-44% in children, teenagers, and adults 1, some studies have raised concerns about its potential impact on children's neurological development, with a meta-analysis finding a significant association between high fluoride levels in water and reduced intelligence in children 1.
Key considerations for minimizing risks include:
- Using fluoride-containing products as directed, with a pea-sized amount of toothpaste for children and supervision to prevent swallowing
- Following dentist recommendations regarding fluoride supplements
- Being aware of potential sources of excessive fluoride exposure, such as bottled drinking water containing up to 8 mg/L 1
- Recognizing the potential for cardiac complications and skeletal fluorosis with chronic high-level exposure 1
The need for fluoridation remains debated 1, and some authors consider that artificial water fluoridation should be reconsidered globally 1. However, at recommended levels, fluoride effectively prevents tooth decay with minimal risk. To balance benefits and risks, it is essential to use fluoride-containing products judiciously and be aware of potential sources of excessive exposure.
From the Research
Fluoride Side Effects and Neurotoxicity
- The potential neurotoxic effects of fluoride have been studied in various research papers, with some suggesting a link between high fluoride exposure and reduced intelligence in children 2.
- However, other studies have found that the current exposure levels of fluoride in Europe do not support the presumption that fluoride is a human developmental neurotoxicant 2.
- Research has shown that excessive fluoride exposure can cause cognitive impairment, with mechanisms including oxidative stress, synaptic and neurotransmission dysfunction, and disruption of mitochondrial and energy metabolism 3.
- Fluoride has also been found to have toxic effects on the kidneys, with studies showing that it can cause kidney damage and dysfunction, particularly in the tubular area of the kidneys 4, 5.
- The relationship between fluoride exposure and neurotoxicity is complex, and more research is needed to fully understand the potential risks and mechanisms involved 2, 3.
Key Findings
- Epidemiological studies have reported an association between high fluoride exposure and reduced intelligence in children, but these findings have been disputed due to limitations in study design and potential confounding factors 2.
- Animal experiments have shown that fluoride can cause adverse effects on the brain and nervous system, but the relevance of these findings to human health is unclear 2, 3.
- Fluoride has been found to accumulate in the hippocampus, a region of the brain important for learning and memory, and to cause cognitive dysfunction in animal models 3.
Mechanisms of Neurotoxicity
- Oxidative stress and inflammation are thought to play a role in the neurotoxic effects of fluoride, with studies showing that fluoride can increase the production of reactive oxygen species and disrupt antioxidant defenses 3.
- Fluoride has also been found to disrupt synaptic and neurotransmission function, which can contribute to cognitive impairment and other neurotoxic effects 3.
- The disruption of mitochondrial and energy metabolism is another mechanism by which fluoride may exert its neurotoxic effects, with studies showing that fluoride can decrease mitochondrial function and increase energy metabolism 3.