Using your body to uncover your vitamin deficiencies.

Pop a multivitamin and you’re covered, nutritionally speaking. Right? But what if you you’re a vegan? You might be lacking in vitamin B12. Don’t get much sun? You probably need extra D. Low bone density? Take calcium supplements. Joint problems? Glucosamine. And everyone knows omega-3s are good for heart health so you ought to add in fish oil...That’s a lot to swallow. Literally.

But how do you decide on your vitamin regimen? Or, for that matter, how does a nutritionist? “I look at overall lifestyle and diet, stress levels, as well as various blood tests,” says Alejandro Junger, MD, author of Clean Eats and founder of Clean, a wellness company.

While a blood test can be used to check a variety of nutrients in the body, unless you’re clearly deficient in something, it’s just a gauge, says Suzan Starler, a nutritionist in Los Angeles. “Let’s assume the normal range for vitamin D is between thirty and one-hundred and yours comes in at sixty. Your doctor may say, ok, that’s fine, go home. But for you, sixty may not be enough to feel your best.”

In addition to blood tests, Starler does “nutrition response testing” (aka “muscle response testing” or “applied kinesiology”), a method she’s been practicing for twenty-eight years (practitioners are certified by The Kinesiology Institute). This is the somewhat mysterious—some might even say wacky—practice of determining what you need depending on how your muscles respond to the energy of certain minerals or vitamins. Or as Starler puts it, “Using the body’s own energy to determine if something is good for you or not.” 

It goes like this: You hold a pill in your palm against your solar plexus, the center of your energy field, and extend your other arm to the side. The practitioner pushes down on that arm. If the substance you’re holding (vitamin C, for example) is good for you, it theoretically brings energy to body and the arm stays strong. To determine the dosage, the practitioner starts with one pill and keeps adding more until the arm weakens and can be pushed down—at which point it’s clear the body doesn’t want that amount. Or is it?

To date, there are no significant studies to back up this method. And even within holistic medical circles there’s skepticism. According to Andrew Weil, MD, there's no physiologic reason to believe that an external evaluation of a muscle's strength can diagnose nutritional problems inside the body.

Which is not to say that the body can’t clue us into our own needs. Mehmet Oz, MD, describes four simple self-diagnostics on The Dr. Oz Show: Press on the breast bone; if it hurts (sign of bone stress), you might have a vitamin D deficiency. Cracks in the corner of the mouth or canker sores mean a lack of B6, while dry skin, brittle hair, or splitting nails point to a vitamin A deficiency. Close your eyes while standing and stick out your right foot; if you can’t balance for three seconds, that’s a sign you’re lacking B12.

Try this at home. Then, if still in doubt, go get a blood test.



  1. Doctor Oz