If you've been, doing all of the right things, eating clean for months and still feel off (fatigued, bloated, foggy, achy), the issue might be a food you tolerate poorly that's still on your plate. The only way to find out is to remove the usual suspects, let the body settle, then reintroduce them one at a time and pay attention to what happens.

That's the elimination diet. It's the clinical gold standard for identifying food sensitivities, and it's been used in functional medicine for decades because nothing else is as reliable. It's also one of the protocols I learned and practiced earning one of my certifications through the Primal Health Coach Institute.

The IgG panels you can order online test for immune memory, which doesn't reliably predict active intolerance. The false positive and false negative rates are both high. The Cleveland Clinic and most functional medicine practitioners explicitly recommend against them as a stand-alone diagnostic.

The foods you actually react to are unique to you. The only test that's reliably gotten people answers is the body itself. Take a food out, feel better. Put it back in, react. That's the data point that matters.

These are the foods that produce most of the trouble for most adults. They overlap with the major recognized allergens (now nine, with sesame the latest addition), plus a couple of additions that are extremely important to lookout for.

You can also pull additional categories depending on your symptoms:

Real, whole food. Simple plates.

Protein.

Vegetables.

Starches.

Fats.

Other.

A quick caveat before you start. This is a self-experiment for generally healthy adults. If you have a diagnosed food allergy or any history of anaphylaxis, suspected celiac disease, you're pregnant or nursing, you're running this for a child, you have any history of disordered eating, or you're managing a medical condition on medication, do it with a qualified professional rather than solo.

Before you pull anything, track everything you eat and how you feel for about a week. Time of day, every food and drink (including cooking oils, condiments, and brands), plus energy, digestion, sleep, mood, and any symptoms. This baseline is what makes the reintroduction phase readable later, and it's the step most people skip.

Remove every trigger food, completely. No "just a little." Partial elimination produces partial information, which is usually worse than no information because you'll talk yourself out of any reactions you do notice.

Keep a daily food and symptom journal. Track energy, digestion, sleep, mood, skin, joint pain, and mental clarity. This data drives the reintroduction phase.

By week 2 most people feel noticeably better, sometimes dramatically. That itself is a finding. If you feel better off a category of food, that category was affecting you.

Reintroduce one food at a time. One every 3 days. Faster than that and you can't tell which food caused which reaction.

How to reintroduce:

Common reaction symptoms include bloating, gas, fatigue, brain fog, joint pain, skin changes, mood shifts, headaches, and disrupted sleep.

If you react, that food stays out, either permanently or until you investigate further (gut healing, leaky gut work, etc.). If you don't react across 3 days, the food is likely fine to add back into your regular rotation.

Suggested reintroduction order:

Gluten is the last food because it has the longest clearance time and the highest inflammatory potential.

Week 1. Usually the hardest. Withdrawal from sugar and caffeine is real. Expect headaches, irritability, and low energy. Push through. It clears.

Week 2. Most people start to feel significantly better. Energy improves, digestion calms, brain fog lifts.

Week 3. Baseline is set. You know how you feel without the common triggers.

Reintroduction. Where the real information lives. Take it seriously. Your reactions will tell you more about your body than any lab panel will.

The point of this is to build a map of your own food triggers. Once you have it, you build the diet around what actually works for your body.

Most people come out of an elimination diet knowing 1 to 3 specific foods they need to keep out of their regular rotation. Pulling those, plus building the rest of the diet on real food, creates a different baseline of how you feel inside your body day to day.

👉 If you feel "off" despite eating clean, food intolerance is the most common hidden driver.

👉 IgG sensitivity testing is unreliable. Elimination is the gold standard.

👉 Pull the trigger foods for 3 weeks. Keep a symptom journal.

👉 Reintroduce one food every 3 days. Track reactions.

👉 Most people identify 1 to 3 trigger foods. Removing those is a quiet life upgrade.

3 uncomfortable weeks for information that lasts a lifetime. Pick the start date. Get the food in the house. Day 1 is when you commit.

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Stay well,

Cameron