Here’s the pitch:  “No need to guess anymore about which nutritional supplements or essential oils you need to take…..the Zyto or iTOVi scanner takes care of all that.”  Does it really? The answer depends upon whether you place more weight upon scientifically validated medical technology or “my-friend/advisor-likes-it-must-work” pseudo-analysis.  In a world where placebos are generally more effective than most nutritional supplements, it is safe to consider both Zyto and iTOVi scanners as placebo machines.   Placebos aren’t necessarily bad… long as you accept that they are little more than sugar pills.   You might be like Alison, who took a Zyto scan administered by a wellness center and was informed that of the 92 “bio markers” scanned over 25% of them were “out of balance”.   She ultimately came to the conclusion that the scan results were rubbish and, in most cases, you’ll find the same once you fully understand what it being peddled.  Now that you’ve been forewarned, let’s do the real analysis.



First off, both the Zyto and iTOVi scanners essentially are biofeedback devices. Biofeedback is technology that helps a person become aware of, and ultimately control, body functions normally not under individual control. These functions can include brainwaves, heart function, breathing, muscle activity, and skin temperature.  These two devices focus upon galvanic skin response, or GSR, which monitors measure skin conductivity from the fingers. In other words, they measures sweat gland activity, which reflects changes in the sympathetic nervous system. Active sweat glands mean a higher tension level. GSR is the same kind of technology used in lie detectors.

Stephen Barrett is an doctor who is an official skeptic.  To pass scrutiny, you have to have a scientific basis for your device or claim.  He gives the Zyto and iTOVi scanners two big thumbs down.    He’s assessed (and used) the Zyto device and finds:

“Skin resistance to an electric current has no value in the diagnosis or treatment of disease. A device claimed to provide information or help with the management of hundreds of diseases and conditions could not be validated without a mountain of evidence substantiating usefulness and reliability. X-ray equipment is approved, for example, because the relationships between x-ray findings and physical findings have been studied in countless millions of cases. As noted above, however, ZYTO’s results are not reproducible, which means that they cannot be validated! ZYTO scans have no proven practical value and could cause large amounts of time and money to be wasted by people who believe the speculations.”

Dr. Barrett isn’t alone.  The FDA warned Zyto in an official 2015 letter that the company must cease and desist from any marketing claims that its devices could diagnose disease or help cure any kind of scientifically-established malady.  It is only cleared for the measurement of galvanic skin response and nothing more.   In 2016, Zyto was compelled to recall all of the software used in its devices.  And a number of state medical boards have acted against chiropractors who have touted Zyto devices;  the Arizona State Board of Chiropractic Examiners under which they were placed on probation for six months, and ordered to pay a $250 civil penalty and to “cease and desist the use of Zyto bioscan technology.

Aside from the absence of legal support to Zyto’s claims, there’s also no scientific support for the proposition that GSR devices will determine your nutritional needs from the drop in your skin resistance.   As noted by the Essential Ninja blog: “By definition of the science of “Galvanic Skin Response” alone, this claim cannot be true.”  We just learned that the limitation for using the physiological arousal mechanism in polygraphs, (a technology under development for more than 100-years or so), is that the skin resistance drops whether it is a positive arousal or negative arousal… or if you are on certain medications… or if you are having a hot flash… it cannot tell the difference.

The long-discredited notion  a substance’s unique energy can be fully characterized digitally and this digital signal impinging on one’s skin will elicit a measurable response from the body is not only unproven but it is a claim that been used since the dawn of quackery.  Both Zyto and iTOVi rely upon diagnosis from the hand only.   The human body does generate an electrical signal and has an electrical resistance,  but it is a stretch to claim that a device can make a diagnosis of the whole body based on electronics signals it receives from one fraction of that body.  It’s an even bigger stretch to claim that the GSR from a hand can steer a person to the appropriate herbal and homeopathic solutions — cures that are already of questionable scientific value.

Another legitimate scientific issue that you must consider is that the resistance of human skin varies from person to person and fluctuates between different times of day. Under dry conditions, the resistance offered by the human body may be as high as 100,000 Ohms. Wet or broken skin may drop the body’s resistance to 1,000 Ohms,” adding that “high-voltage electrical energy quickly breaks down human skin, reducing the human body’s resistance to 500 Ohms.  If the human skin’s electrical properties changes so much in the course of a day, from person to person,, then logically, a device cannot claim to make a whole body analysis of health from this one sample site.  Moreover, it can’t tell the effectiveness of kidneys,  liver, cholesterol levels, blood pressure, triglyceride levels, thyroid profile, enzyme, RBC count, white blood cell count, or other peer reviewed key health indications.

Interestingly, these device peddlers don’t deny this scientific fact – they just sort of sidestep it.   On the  FAQ page of their website, ZYTO states measurement results are not likely reproducible.   Here’s how Zyto explains it:  “Because ZYTO technology interfaces with the body’s fastest moving component, energy, biosurveys can collect a significant amount of information in a short amount of time. Since energy moves and fluctuates so quickly, you are likely to see differences if you repeat a biosurvey and compare individual data points.”  The scientific term for this explanation is rubbish.  Which probably explains why ZYTO Corp stock price was trading at $0.03 per share with an overall valuation of just over $1M (last public income statement was 2011, before it was delisted).


If you choose to invest your money into any Zyto products, it may be worth checking out the comments from the employees of that company. is a useful resource for learning more about how companies operate.  Notably, a number of employees state concerns about the lack of real science supporting the claims of the company.   They also reveal a flashing red warning light:  most of the money made by sellers of the device are based upon commission.

Another red flashing warning light comes from from the Zyto company’s own user manual.  It states:

The ZYTO Balance 5.0 is designed specifically to accomplish three objectives:

  1. Identify specific nutritional supplements you sell, for which your patient shows a biological preference.
  2. Identify the services you offer in your practice for which your patient also shows a biological preference.
  3. Generate referrals for your practice.

That’s right, the company admits that its device is a marketing tool for practitioners.   And, while we are on that topic, let’s look a bit more at the iTOVi device, which is an unabashed marketing tool for two essential oil companies.   The iTOVi device appears to be very similar to the Zyto device in most relevant ways.  It’s marketing appears to be directed at direct sales professionals in the supplement industry and essential oil . Even their sales approach to have a network marketing aspect; it claims you can  recoup your investment by getting 5 others to purchase their product.  That’s why the company pushes referrals as a basis for its value. (Think MLM)  But, like Zyto,  iTOVi admits that its results are not reproducible:  “As the scanner gathers more information about your body’s responses, the more intuitive the results become. Over time, past information influences the scan less and less, allowing the recommendations to be impacted by your current needs.”

If you really want your brain scrambled with vague and conflicting sales pitches abou the iTOVi, just check out this video pitch.


So what is the basis upon which people actually believe the nutritional and essential oil recommendations made by the these devices? According to the Essential Ninja blogger, one of many possible reasons for this, (and one that I am currently fascinated with), could be because essential oils are generally high in beneficial bioactive phytochemicals. Herbs, spices and other foods high in these naturally occurring chemical compounds have been shown to reduce chronic inflammation in the body. Since many complaints people have can be associated with chronic inflammation, any reduction can appear to have a broad effect.   Consider this note posted on a blog about Zyto:

“I am a ZYTO Elite 5.0 practitioner here in Lexington, KY. I will preface, that I am medical training and the science aspect of the medical model or frame of reference is being able to repeat results to validate something. In using the ZYTO and this type of energy technology, it is not really how it works and we need to take into consideration – that the body is really an energy system…each cell is really a single unit of pure energy. We are a pure energetic & biological system always changing and being effected by our surroundings, foods, sunlight, magnetic pull of the moon…. etc. So, repeating the same result is almost impossible. As a practitioner, how I use the program is that I look for consistencies and patterns to help me & my clients determine what is the best approach to take for their health concerns.”

If this kind of thinking worries you (and it worries the hell out of us), then we strongly recommend that you avoid practitioners who use either of these devices and their recommendations.