Essential tremor, affecting 1 in 25 adults over 40 and up to 1 in 5 of those in their 90s, is one of the most common neurological diseases. In addition to the potentially debilitating hand tremor, there can be other neuropsychiatric manifestations, including difficulty walking and various levels of cognitive impairment.
Might beta-carboline neurotoxins play a role in essential tremor? Harmane is one of the most potent of the tremor-producing neurotoxins. Expose people to harmane, and they develop tremors; take it away, and the tremors disappear. What if we’re exposed long-term? A recent study at Columbia University, highlighted in my video, Essential Tremor and Diet, found that those with essential tremor have much higher levels of this toxin in their bloodstream compared to those without tremor. Furthermore, the higher the harmane levels, the worse the tremor. The highest levels are found in those who have both essential tremor and cancer, suggesting harmane may be playing a role in both diseases.
How did folks get exposed to these chemicals? Primarily through meat: beef, pork, fish, and especially chicken. So if this potent, tremor-producing neurotoxin is concentrated in cooked muscle foods, is meat consumption associated with a higher risk of essential tremor? Another Columbia University study found that men who ate the most meat had 21 times the odds of essential tremor. To put that in context, if we go back to the original studies on smoking and lung cancer, we see that smoking was only linked to about 14 times the odds, not 21.
Blood levels of this neurotoxin may shoot up within five minutes of eating meat. Five minutes? It’s not even digested by then. This rapid uptake is indicative of significant absorption directly through the mouth straight into the bloodstream, bypassing the stomach and, most importantly, bypassing the detoxifying enzymes of the liver. This may lead to higher exposure levels in peripheral organs, like the brain.
Due to its high fat solubility, harmane accumulates in brain tissue, and, using a fancy brain scan called “proton magnetic resonance spectroscopic imaging,” higher harmane levels have been linked to greater metabolic dysfunction in the brains of essential tremor sufferers.
Harmane is also found in certain heated plants, like tobacco. A broiled chicken breast has about 13 micrograms of harmane, and cigarettes average about one microgram, so a half pack of cigarettes could expose us to almost as much of this neurotoxin as a serving of chicken. Harman is created when tobacco is burned, and also when coffee beans are roasted. However, coffee intake has not been tied to increased risk (and neither has tobacco for that matter), so it may be something else in meat that’s to blame for the 2,000 percent increase in odds for this disabling brain disease.
Other compounds created in cooked meats may also have implications for cancer risk: