What is nutrition response testing? 

nutrition response testing - female practitioner assessing male patient

Nutrition response testing (sometimes simply called NRT) is a technique that alternative and holistic health practitioners like chiropractors often use to diagnose underlying causes of health concerns and return the body to optimal function.


The theory behind this technique was developed back in the 1960s by George Goodheart Jr. Since then, it has gained in popularity and is now widely used. In one survey, more than 40% of chiropractors in the US reported using this technique in their practice.1 2 3


Whether you’ve come across this tool in your own healthcare journey or you are curious to learn more about it, we’ve got you covered. Keep reading to learn what nutrition response testing is, what some of the potential benefits are, and what the research says about this technique.


What is nutrition response testing?

Nutrition response testing is a form of something called applied kinesiology, also known as muscle strength testing. Applied kinesiology is a tool practitioners like chiropractors and naturopaths use to diagnose and treat various health concerns. It has been around for more than half a century and has become a very popular element of many alternative and complementary healthcare practices.


This technique uses the body’s own neurological reflexes to determine underlying causes of health concerns, such as deficiencies or toxicities, and also helps to identify the proper course of care to correct the problem (for example: dietary changes, supplements, or other holistic approaches). It draws on several different theories of health, including kinesiology (biomechanics) and traditional Chinese medicine.1 2


The idea is that when there is stress in a part of your body or some sort of negative input to the body, the nervous system will respond with weakened energy in the muscle being tested.


So, when a practitioner applies force to your muscle and you are unable to resist the pressure, it is believed to be a cue that the body system or the specific thing being tested at that moment is weak and in need of support.


Proponents claim that through assessing the body’s reflexes and using muscle strength testing, we can tap into what the body needs to communicate about stressors, imbalances, and dysfunction within.


The nutrition response testing process

woman sitting on exam table talking to doctor

A practitioner will usually begin the process with a thorough medical history and examination.


Next, they’ll move into analyzing, diagnosing, and choosing treatment paths by testing your muscle strength. Usually, a practitioner of nutrition response testing will use your arm to test your muscle strength. They will often have you extend one arm out in front of you and then push down on it—asking you to try to hold your arm in place and to resist the pressure applied to it.


At the same time as they apply gentle force on your arm, the practitioner may also place their opposite hand on various acupressure points across your body that correspond to the organs and organ systems. Alternatively, they may have you hold something in your other hand (such as a food, a supplement, an allergen, or something else), or ask a question (out loud or in their head). Whether or not you are able to resist the force pushing down on your arm tells the practitioner whether this is a point of stress on the body or a point of strength.


To illustrate how the muscle testing process works, let’s look at a brief example:

  • Let’s say during the nutrition response testing process, your arm drops under the pressure when the practitioner is contacting an acupressure point that corresponds to the liver. This might tell them that there is some sort of weakness or stress in the liver that needs to be addressed.
  • Next, they might ask you to hold certain foods or supplements in your hand while testing your muscle strength in order to see which ones are needed to bring the liver back into balance. If your arm drops when holding a certain substance, that substance isn’t considered to be right for you. But if your arm holds steady against the pressure, then that is thought to signify that the food or supplement will help to correct the imbalance in your liver and restore normal function.


Nutrition response testing is usually done across multiple visits to assess how the treatment plan is working and to monitor for changes. Ideally, as treatment continues, the muscle testing will reveal stronger and stronger responses where there was once weakness—suggesting greater balance and harmony building within the body.


This tool is also usually used in combination with other treatments and therapies as part of a holistic approach to care, so it may be used alongside nutritional therapy, acupuncture, massage therapy, chiropractic manipulation, and more.


What are the potential benefits?

stacked rocks on seashore

Nutrition response testing has a wide variety of applications. When used in practice, it is often used as a very versatile tool with a wide range of potential benefits. Practitioners may use it to help uncover the root of your symptoms, or to get answers about chronic conditions or illnesses that have proven hard to treat. Or, they may use it to help create a more personalized approach to nutritional and supplement recommendations.


Some of the most commonly reported benefits of nutrition response testing include:

  • Determining the state of organ and organ system health
  • Supporting health concerns ranging from skin conditions to digestive issues to fatigue to chronic pain
  • Assessing and correcting nutrient deficiencies
  • Identifying and treating allergies or sensitivities
  • Detecting toxicities in the body and supporting the detoxification process
  • Finding imbalances in energy flow, chakras, or meridians and bringing them back into balance
  • Identifying and supporting mental or emotional stress
  • Detecting and treating underlying infections1 2


It is important to note, however, that there is limited scientific evidence behind this practice. The list above simply offers some of the potential benefits touted by nutrition response testing practitioners and their patients.


Does nutrition response testing work?

Nutrition response testing is used by a wide variety of practitioners across the globe. And many people have very positive experiences when treated with this technique. There are countless anecdotal and clinical reports demonstrating positive results for everything from allergies to chronic pain to fatigue.


There are some older studies suggesting that NRT can accurately predict food allergies. And there are also some interesting studies suggesting that practitioners can distinguish truths from lies when using kinesiology techniques more easily than when they rely on intuition or chance alone.4 5


In contrast, one study found that applied kinesiology was not an accurate method of diagnosing nutritional intolerance. However, they did suggest that it could still be valuable as a preliminary testing tool.6


As of now, there is no strong evidence from the scientific studies telling us that nutrition response testing works. However, not many scientific studies have been done on NRT. As more research is done on the subject, we may learn more about it and its potential benefits.


Is nutrition response testing right for you?

woman's hand holding a supplement bottle

Nutrition response testing is an alternative method for analyzing the state of health in your body and to help guide the care process.


It is non-invasive and considered quite safe and harmless. So even though there’s no strong scientific support from the research, it may be worth a try if you are interested in approaching your health and healing from a new perspective.


If you do choose to try it out, find a healthcare practitioner like a chiropractor, osteopathic physician, or naturopath who is trained extensively in the techniques of nutrition response testing.


Also, be sure you continue to work closely with the rest of your healthcare team to ensure that any health concerns are being monitored and cared for. As always, consult with your doctor before beginning any therapies or new treatment plans.


Nutrition response testing and ZYTO technology

Though not diagnostic, a ZYTO bioscan is similar to nutritional response testing in that we’re looking for how the body responds when a stimulus, such as a nutritional product, is introduced. With ZYTO technology, however, we introduce digital representations of the items to the body rather than the actual items. This allows us to scan for several items in a shorter amount of time. 


Additionally, rather than the practitioner seeing if the body responded positively or negatively, a ZYTO scan measures the body’s galvanic skin response via the ZYTO Hand Cradle device. We can not only observe whether the body responded coherently based on these measurements, but also see how strong the response was.




About Chelsea Clark
Chelsea Clark is a writer and certified health and wellness coach who is passionate about supporting others along their own health journeys. She enjoys helping people make positive, lasting changes so that they can live the happiest, healthiest life possible.




1. “Applied Kinesiology” Healthy Lifestyle Brands, LLC. Drweil.com. 

2. Jensen, Anne M. “Muscle testing (kinesiology): panacea or placebo?” The Conversation US, Inc. Theconversation.com

3. Cuthbert, S.C. & G.J. Goodheart Jr. “On the reliability and validity of manual muscle testing: a literature review.” Chiropractic & Osteopathy 15, no. 4 (2007).

4. Schmitt, W.H. Jr & G. Leisman “Correlation of applied kinesiology muscle testing findings with serum immunoglobulin levels for food allergies.” The International Journal of Neuroscience  96, no. 304 (1998): 237–244.

5. Jensen, A.M., R.J. Stevens, & A.J. Burls. “Estimating the accuracy of muscle response testing: two randomised-order blinded studies.” BMC Complementary and Alternative Medicine 16, no. 1(2016): 492.

6. Pothmann, R., S. von Frankenberg, et al. “[Evaluation of applied kinesiology in nutritional intolerance of childhood].” Research in Complementary and Natural Classical Medicine  8, no. 6 (2001): 336–344.


The information provided in this article is intended to improve, not replace, the direct relationship between the client (or site visitor) and healthcare professionals.

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