The Top 3 Functional Medicine Tests You Need

Robin Berzin, MD
July 19, 2018

Typical lab work just looks at the basics, but there is a lot more that your body can tell you. That’s why you need tests that go deeper.

People seek out a functional medicine practice like Parsley Health when they’re frustrated. Desperate even. They might feel like they’re doing everything right but their weight is still climbing, they’re not sleeping well, they have horrible PMS or low libido, and they’re bloated and exhausted. Sound familiar? We use medical tests that other doctors don’t to get to the cause of these symptoms and help you feel better.

How specialized medical tests can help you

One of my patients, a 31-year-old woman who works in finance, is the perfect example. She was doing 5 bootcamp and spin classes a week, working long hours and falling into bed exhausted but unable to get a good sleep . Her periods were becoming weirdly irregular and she was feeling bloated all the time. She knew a 10-minute visit with her primary care doctor and a prescription for a sleeping pill wasn’t the ultimate answer, so she came to Parsley Health for expert advice that would take a 360 degree look at her life, her diet, her medical history, and her symptoms, helping her get to the root of the problem.

I realized we needed to do specialized medical tests to understand why she was feeling so badly. First, we did a Parsley baseline profile, which includes far more blood tests than most doctors look at. Right off the bat, we discovered an imbalance between her estrogen and progesterone hormones and B12 and magnesium nutrient deficiencies . From there we did a cortisol test and learned that her high nighttime cortisol was keeping her awake at night. We also did an in-depth poop test (yep, a 3-day stool sample) that was key to discovering she had an imbalance in her gut microbes and low digestive function. Finally, we did a genetics test that told us that she was slow at breaking down certain estrogens and slow at making neurotransmitters like dopamine and serotonin.

These insights were key to guiding my patient’s care. We used natural medical grade supplements (NOT the stuff at the grocery store) to help her balance cortisol and estrogen, improve protein absorption, and resolve her gut issues through probiotics and by replenishing nutrients she was low on. Her health coach also guided her through an elimination diet that helped her identify food sensitivities and I prescribed an anti-fungal medication that killed off the yeast overgrowth in her gut.

She is now sleeping better, her menstrual cycles are regular, her PMS is gone, her digestion is better, and she lost 10 lbs without working at it. That’s why I recommend everyone get these three functional medicine tests done.

The 3 medical tests that every person needs

1. Four Point Cortisol Test

This test looks at the health of your adrenal glands, which produce the stress hormone cortisol. You can do it at home and it’s best done on an average day for you, so ideally a work day. You spit in a tube four times that day—once when you wake up, once before lunch, once before dinner, and once before bed. The results show us a curve of your cortisol levels over the course of the day. Cortisol should start high in the morning, when you need that get up, and go and come down throughout the day. If your curve looks different, cortisol could be the reason you’re experiencing weight gain, high blood pressure, blood sugar imbalances, or hormone imbalances.

2. The GI Effects or CDSA 2.0 3 day stool test

This medical test reveals imbalances between the good and bad bacteria in your gut, identifies any overgrowth of yeast, and finds parasites. It also tells us if you have inflammation in your digestive tract and if the digestive juices in your pancreas are low, which could indicate that you’re not properly absorbing nutrients. For some people with digestive and autoimmune problems, this test is a game changer.

3. Genomind Genetics profile or 23&Me

While science is just at the tip of the iceberg when it comes to understanding genetics, there are a lot of things your DNA can reveal about your genetic potential. Maybe you’ve already done a DNA test before, but did you really understand the results? A functional medicine team can help you put that information together in a way you can use in the context of your life. This means that we can look at genetics and make specific recommendations for diet, exercise, and supplements that will help you metabolize hormones like estrogen in a healthier way.

Robin Berzin, MD

Dr. Robin Berzin is the Founder and CEO of Parsley Health, America's leading holistic medical practice designed to help women overcome chronic conditions. She founded Parsley to address the rising tide of chronic disease in America through personalized holistic medicine that puts food, lifestyle, and proactive diagnostic testing on the prescription pad next to medications. Since founding Parsley in 2016, Dr. Berzin has seen 80% of patients improve or resolve their chronic conditions within their first year of care, demonstrating the life-changing value of making modern holistic medicine accessible to everyone, anywhere. Parsley is available online nationwide.

Dr. Berzin attended medical school at Columbia University and trained in Internal Medicine at Mount Sinai Hospital in New York City. Her book, Prescription for Happiness: How to Eat, Move, and Supplement for Peak Mental Health, was published by Simon Element in January 2022.

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