80% of your immune system resides in the gut. If your immune system is attacking itself—whether it’s the thyroid with hashimoto’s, the joints with rheumatoid arthritis, or the brain with MS—the problem most often stems from what you put inside your body.

Often, staples of your diet—Bread, grains, dairy, etc.—can cause food sensitivities. Unlike allergies, these are sneaky and subtle. They’re frequently the cause of minor discomforts—think gassiness, bloating, fatigue, headaches—that arise 24-48 hours after consumption. This makes them difficult to determine, and even harder to avoid.

Each person is different, displaying unique sensitivities to foods. I might have trouble digesting tomatoes, while you might struggle with gluten. Your ability to digest depends on enzymes and your gut microbiome (or all of the bugs that set up shop in your gut), how much ‘good’ bacteria has been wiped out by antibiotics, what your stress levels are during consumption, and more.

Disclaimer: I dislike the word “diet”; it’s too closely related to trends and fads. I like to take a holistic look at my patients’ environments to help them find sustainable lifestyle solutions for the next 20 or 30 years. So how do I help them determine which foods are best for their unique terrain, and which to avoid?

Elimination Food Plan: Finding the Culprit

An Elimination Food Plan involves removing certain foods from your diet to determine which you in particular are sensitive to.

Begin by excluding top allergens for three or four weeks. These include foods like gluten, caffeine, dairy, soy, corn, nightshades like peppers and tomatoes, and sugar that often cause sensitivities. After, slowly reintroduce these foods one by one (giving each three days to allow for a reaction)—and see how your body responds on a clean slate.

Suddenly, it’s clear that the cream in your coffee was making you gassy, or that dairy was causing constipation. Once identified, these foods can be eliminated—along with their troublesome symptoms. With food sensitivities removed, your immune reaction to them disappears as well—allowing your gut to heal and your immune system to strengthen.

A food sensitivity test is one way to measure your antibody response to different foods and see what you’re sensitive to. However, I recommend the elimination plan for most, as it allows you to actually feel your body’s reactions. Plus, it’s free!

Modified Paleo: Channeling the Cave Men

The Paleo diet eliminates all foods that our cave-dwelling ancestors didn’t eat—basically everything besides fresh fruits, vegetables, and meats.

While Paleo excludes processed and unnatural foods, it doesn’t cater to personal sensitivities. Eggplant and bell peppers are technically Paleo-kosher; they’re also common foods people are sensitive to.

I recommend a modified Paleo diet, which combines elimination with the standard Paleo diet. This allows you to determine your sensitivities, while playing by Paleo rules.

Low Mercury: Tuna Are Friends, Not Food

Many of my autoimmune patients present with elevated levels of heavy metals in their bodies. This can cause fatigue, mood swings, insomnia, nervousness, anxiety, weakness, and worsening of their disease.

In such cases, I advise steering clear of foods high in mercury and mercury dental amalgams—such as tuna. The lower your mercury levels, the healthier you’ll feel.

If you’re suffering from unexplainable symptoms, a food sensitivity could be the answer. Let’s target the cause of your discomfort.