Your Immune System can Change your Brain

Traditionally we believed that the brain was a highly protected organ, seperate from the rest of the body. It sits in the skull, protected by the meninges and the blood-brain-barrier, which allows only an ultrafiltrate of the blood to reach the brain. We also thought it was impossible to heal or create neurons, the cells in the brain. This led to a sort of fatalistic idea of brain health: the brain you have is the brain you get and there’s not much you can do about it.

I think we all know intuitively that this is false. Afterall, if the brain is the most important part of the body, and every other part of the body can heal, why wouldn’t the brain also be able to heal? How can the brain control the entire body if it is entirely cut off from the rest of the body, besides by tracts of nerves? How is it that external factors can damage the brain?

Slowly science had made concessions on this topic. We realized that heavy metals can be deposited in the brain. “Mad as a hatter” is a phrase that originated because mercury was used to make felt, which was used extensively in the hat-making industry. Hatters eventually developed tremors, slurred speech, and even hallucinations. Remember John Wilkes Booth, the guy who shot Abraham Lincoln? Well the guy who shot Booths (against orders) was a hatter before he joined the military. He ended up in an insane asylum, escaped, and disappeared. This is all to say the things we touch can end up in our brain.

We learned that the olfactory nerve which starts in the nose has a direct physical link to the brain. That means anything you are smelling is touching your brain. Aromatherapy works because the molecules are so small and light they mix with the air and travel readily to the brain. Oral lavender oil works as well as xanax for anxiety in the research, but for instant relief, just inhale it. 

We conceded that small molecules can make it from the bloodstream to the brain, hence we developed all sorts of fun drugs, from Abilify to Zoloft. These all interact with receptors for neurotransmitters, and some turned out to be highly addictive, and others make you suicidal, but some also improve mood. We have found a lot of plants that make small molecules that impact our brain as well: St. John’s wort, lavender, mimosa, even gentle chamomile and everybody’s favorite, cannabis.

In 2015 a study came out revealing that scientists had discovered lymphatic vessels in the brain. Our lymphatic system is the surveillance network for our immune system and is a highway for immune cells. This means our immune system has direct access to our brain.

Why do we care? Because this means anything that impacts our immune system could also impact our brain for better or for worse. Think about how your brain feels when you are sick. Your body feels terrible and your brain feels cloudy, dull, or slow. This is because the immune system is the ultimate source of inflammation in the body. Now that we know there is a direct connection between the brain and the immune system, it becomes glaringly obvious that we have yet another way to impact the brain’s heath. Here are a few herbs that might help bridge that gap between the brain and immune system

  •  Garlic: This is a classic immune system herb that has recently been researched for its neuro-protective effects in diseases like Alzheimer’s.

  • Lemon balm: long used as a calming herb, lemon balm also turns out to be anti-viral

  • St. John’s wort: this herb is most well known for its positive impact on depression, but historically it has been used as an antiviral and topically for wounds.

  • Calendula: a lovely flower used for wound healing and all sorts of skin conditions because of its ability to calm inflammation and prevent infection. It has also been found to have neuro-protective effects against brain toxins like MSG.

A lot of the research on this topic is just getting published, but it’s something naturopathic doctors have been wise to for a long time. We know that all the systems in the body work together and that sometimes to fix system, you have to address the other systems. To fix a brain, we may need to look at the immune system.