Fluoride has been no stranger to controversy in recent years but few issues raise eyebrows and heart rates more than its connection to Alzheimer's disease. There has been much debate over the past few decades over whether Alzheimer's disease and other forms of dementia, can be attributed to so-called deadly components in our drinking water. Studies since 1965 have postulated that aluminium is responsible for the creation of amyloid plaques in parts of the brain known to be the focus of the Alzheimer's and dementia conditions. In one study, researchers injected an aluminium solution into the brains of live rats and over a period of a few weeks watched their cognitive conditions deteriorate. Post mortem analysis of the brain tissue revealed the formation of amyloid plaques in the hippocampus and the amygdala, the areas of the brain associated with memory.
Later studies on the brains of Alzheimer's disease patients found problems in the connectivity of the hippocampus, with evidence of amyloid plaques. In patients with more advanced cases of dementia and Alzheimer's, damage and plaque formation, which contained high concentrations of aluminium, was also found in the amygdala. These studies suggest that patients first experience symptoms of dementia when there is damage to the hippocampus and when the damage spread to the nearby amygdala. The symptoms worsen significantly.
Time and time again aluminium based plaques have been found at the centre of Alzheimer's and dementia studies. The puzzling aspect for researchers has been the mechanism by which aluminium is allowed to penetrate through protective structures, into the vital areas of the brain. Humans are exposed to a bombardment of toxins on a daily basis, ranging from pollutants in our atmosphere to chemicals in our food and drinking water.
These chemicals, while commonly found accumulated in body tissues over time, are normally kept out if our brain by a protective structure known as the blood-brain barrier or BBB. The BBB is a is a highly selective semipermeable membrane that separates the circulating blood from the brain’s extracellular fluid in the central nervous system (CNS). It is comprised endothelial cells, which are connected by tight junctions and astrocytes (star cells - so named for their shape) which support the barrier cells and are thought to be extensions of the central nervous system.
The BBB allows the passage of water, some gases, and lipid-soluble molecules by passive diffusion, as well as the selective transport of molecules such as glucose and amino acids that are crucial to neural function. As mentioned, this barrier also plays a vital role in excluding harmful substances, such as toxins and heavy metals from brain tissue. Therefore, the mechanism by which aluminium is able to enter the brain tissue and settle in the hippocampus was unknown. Now some researchers believe that the answer is fluoride in our drinking water. Studies conducted in Japan, USA, Canada, Nigeria and Australia have postulated that fluoride acts as trans-cerebral Trojan horse. Aluminium by itself is instantly recognized by the BBB and immediately repelled. However, when it is bound to fluoride the BBB is unable to recognize the foe and subsequently small amounts are allowed to leach through. Chronic exposure through the drinking water that we consume daily is where the problem is thought to arise.
However, for every study performed and paper published that reinforces this correlation, another publication is rolled out preaching to the contrary. It is therefore left to us as individuals whether we want to consume water which has fluoride as but one of the many questionable elements tagged to it, or if we want to seek out a better solution. As people the choice is ultimately ours and either way we have to deal with the consequences. It is however up to us as individuals to seek to better educate ourselves so as we can make informed decisions.