Scientists have found that dietary change could be an effective low-cost treatment for people with chronic pain.
Preliminary research from a small pilot study carried out in Meru, in eastern Kenya, shows a link between chronic pain and consumption of glutamate, a common flavour enhancer found in western and non-western diets worldwide.
The results, published in the journal Nutrition, demonstrated that when participants cut monosodium glutamate from their diets, their symptoms improved.
"This preliminary research in Kenya is consistent with what I am observing in my chronic pain research here in the US," said Kathleen Holton from American University.
"We don't know what exposure is leading to this susceptibility to dietary glutamate, but this pilot study suggests the need for a large-scale clinical trial, since dietary change could be an effective low-cost treatment option for developing countries," Holton said.
As researchers study glutamate, they are gaining insights into how the chemical works in the human brain and body. In the brain, glutamate is a common neurotransmitter.
It also can act as an excitotoxin, over-stimulating and damaging or killing nerve cells.
Glutamate is also a naturally occurring chemical in some foods, like soy sauce and parmesan cheese, but is more commonly found as a food additive.
In the Kenya study, the goal was to test whether a dietary intervention could perform as well as or better than over-the-counter medication in relieving pain.
With a sample size of 30 participants, the researchers tested the effects of removing MSG, increasing water intake, or a combination of both, relative to acetaminophen (the main treatment option available in Meru).
The participants experienced chronic pain for at least three months or more and in at least three quadrants of the body.
Similar to what is seen with widespread chronic pain patients in the US, most also suffered from other neurological symptoms, including headaches or migraines, chronic fatigue, cognitive dysfunction, and sleep issues.
"This would be incredible if we could impact chronic pain simply by making slight modifications to diet," said Daniel J Clauw from the University of Michigan in the US.