The gut as a second brain

Boulder naturopaths say food allergies can cause depression

Lisa Ganora teaches a class on food allergies.
Photo by Abby Faires

We know that certain foods can affect the way we feel. But what about the way food makes us think?

An increasing number of studies have shown that allergies, food sensitivities and intolerances are linked to mental health and, more specifically, to depression. Boulder naturopathic physicians and herbalists ride on the forefront of this food-depression frontier, yet they caution that food allergies and sensitivities aren’t a be-all, end-all solution.

“I think there is definitely a link between food allergies and depression,” says Maile Green, a nurse and licensed acupuncturist. “That is not to say that there aren’t other factors, that depression isn’t from other things. But I think that frequently, food allergies play a role.”

But it’s not just allergies that can have serious impacts on the brain. Harder to test for, and perhaps even harder to define, food intolerances and sensitivities can wreak just as much havoc as allergies.

What’s the difference? Food allergies are often equated with extreme, anaphylactic responses. For example, when someone has a severe peanut allergy, tissues in their body release histamine and other substances, which can cause airways to tighten. They often experience difficulty breathing and need immediate medical attention, as their entire immune system works to fight that harmful substance. Sensitivity or intolerance won’t cause such strong physical responses, but they still matter.

“‘Food allergy’ means that the immune system is creating an immunological response to a food,” says Julieanne Neal, a naturopathic doctor. “Food sensitivity or intolerance may not have that immediate impact on the immune system, but it’s still a negative response to food.”

When a person has a food allergy, they often produce specific immunoglobulins, or antibodies, in response to the allergen. These antibodies will attach to the harmful substances so that the immune system can destroy them. Doctors can then test for specific antibodies to determine if someone has a food allergy or not.

“Sensitivities or intolerances may not have that immune response,” Neal says. “So they aren’t measurable. You can’t always test for immunoglobulins like with allergies.”

Neal and Green all agree that the “gold standard” for food intolerances and sensitivities, therefore, is an elimination/re-challenge, whereby patients eliminate a specific food from their diet for six weeks and then reintroduce that food, in order to investigate the effects it has on their health — including to see if food is contributing to depression.

“There can be a lot of problems with various tests,” says Lisa Ganora, director of the Colorado School of Clinical Herbalism. “You can have false negatives, false positives, or the test might be missing certain types of antigens.”

With elimination/re-challenge, people “let all the aggravation out of their system,” according to Ganora, and can keep a symptom checklist to see what has or hasn’t improved.

“In medicine, we love our tests and love being able to have an objective test to say see, this is how it is,” says Green. “But your health is something that you live with all the time. How much do you care about a test result when you feel bad when you eat something? It’s a common sense thing.”

Food sensitivities act as a sort of constant, low-grade irritant, changing the way the body absorbs what it has been fed. When it comes to food sensitivities, people learn to get by with this sort of low-grade “ickyness,” Green says. But underneath the surface, the body is producing a constant inflammatory reaction, similar to when a person is sick with a cold or flu.

“By the second day [of having a cold or flu], you start feeling depressed on top of being fevery and sniffly,” Green says. “That’s a reaction to inflammatory molecules that are running around in your body. Part of the way that we react to them is that we start feeling bad, and the point of that is to stay in bed and rest, and we don’t feel like doing a lot.

“Gluten, soy and dairy are just so ubiquitous in our daily food that’s around, that people get accustomed to feeling bad,” Green says. “And they don’t attribute it to what they’re eating. They’re just feeling bad because it’s always there.”

More than 90 percent of the body’s serotonin is found in the gastrointestinal tract. Serotonin is a hormone and a key player in the functioning of that tract. It also regulates aggression, appetite and mood. Lower levels of serotonin, caused by a damaged, inflamed or leaky gut, could seriously affect a person’s mood.

Ganora says that she has seen over and over again, in her students and in the clinic at the Colorado School for Clinical Herbalism, that by eliminating specific food allergies or intolerances, clients and students see tremendous improvements in their mood.

For Ganora, there is no separation between the mind and the body.

“It’s all the same blood, the same neurotransmitters, same cytokines, the same molecules,” Ganora says. “People tend to forget that and think that depression is all in the mind — it’s all in their head. But there is no separation. If food is causing an ongoing, low-grade, chronic inflammation in your body, it’s gonna affect your mind, energy and spirit.”

Green, Ganora and Neal all argue that conventionally trained doctors grow out of a tradition where emergencies are priorities. But when a health problem doesn’t present an emergency, there isn’t an immediate need to solve the problem.

“When an allergy is anaphylactic, there is a chance it could kill you,” Green says. “A food allergy isn’t so bad.”

Green says that we are an incredibly varied species, and wellness isn’t a one-size-fits-all concept. It’s highly individualized.

“Our bodies are designed to help us figure out what’s good for them,” Green says. “I think that naturopaths can be helpful allies in trying to sort things out, but there’s not really one answer that’s true for everybody. If it were that simple, it would have gotten figured out a long time ago.”