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Nutrigenomics – Not Ready for Prime Time

Quackery in medicine takes many forms – use of bad science (pseudoscience), fraud, and reliance on mysticism are a few examples. Perhaps the most insidious form of dubious practice, however, is to use genuine and promising medical science to promote treatments that are simply not at the point of clinical application. New treatments, and especially new approaches to treatment, in medicine often take years or decades of research before we get to the point that we have sufficient clinical evidence of safety and effectiveness to apply the treatment in clinical practice.

One example of the premature promotion of an otherwise legitimate scientific medical treatment are the many dubious stem cell clinics promising cures for serious diseases. Stem cell science is real, but we are still in the long period of build up when we are mostly doing basic and animal research. Human clinical trials are just beginning.

Another treatment approach that is being prematurely promoted by some is nutrigenomics. The claim is that by analyzing one’s genes a personalized regimen of specific nutrients can be developed to help their genes function at optimal efficiency. One website that promises, “Genetics Based Integrative Medicine” contains this statement:

Nutrigenomics seeks to unravel these medical mysteries by providing personalized genetics-based treatment. Even so, it will take decades to confirm what we already understand; that replacing specific nutrients and/or chemicals in existing pathways allows more efficient gene expression, particularly with genetic vulnerabilities and mutations.

The money-quote is the phrase, “it will take decades to confirm what we already understand.” This is the essence of pseudoscience – using science to confirm what one already “knows.” This has it backwards, of course. Science is not used to “confirm” but to determine if a hypothesis is true or not.

As with the stem-cell quackery, this idea (of studying one’s genes in order to personalize therapy) is not itself pseudoscience. It is, in fact, an area of legitimate research. We already use genetic analysis to diagnose certain diseases, and to target chemotherapy. We are beginning to identify specific genes that affect how different individuals metabolize and respond to specific drugs. While genes are not necessarily destiny, our genes do exert a powerful influence over our health. They are already an important part of science-based medicine.

Further, as genetic analysis becomes more rapid and cost effective, there is the increasing potential that it can be used as part of a routine screening health evaluation in order to identify susceptibilities, target preventive treatments, adjust behaviors to target risks, and guide therapy. However, similar to stem cell treatments, our current knowledge base with respect to genetic predispositions is still in its infancy. What is well established is already incorporated into mainstream medical practice. The rest is a matter for research, not current practice.

This creates an opportunity for exploitation, however – using current cutting edge research to make clinical claims that are years or decades premature by pretending to have knowledge that simply does not exist. This type of medical pseudoscience is also a manifestation of one common tactic among dubious practitioners – basing clinical claims on pre-clinical scientific research. This is especially insidious and difficult for the non-expert to properly evaluate (which makes for effective pseudoscientific marketing).

A November 2012 review of the field of nutrigenomics states:

It has, however, proven very challenging to define an individual’s responsiveness to complex diets based on common genetic variations. In addition, there is a limited understanding of what constitutes an optimal response because we lack key health biomarkers and signatures.

In other words – the relationship between nutrition and personal health is complex and we do not yet have the scientific knowledge to apply to practice. The article concludes that, while promising, the field is not yet ready for the marketplace.

One way to look at the issue of nutrigenomics is moving from population-based nutrition data to individual, or personalized, data (specifically, genetic profile). Health promotion advice is now based largely on population-based data – what is statistically likely to happen with respect to risk factors and disease outcomes. Nutrigenomics research focuses on tweaking this advice (not replacing it) with an additional level of detail targeted to an individual’s genetics. The application would go something like this: you have a blood test to test for specific gene variants. If you have one specific variant then that might predict a need for a higher level of one specific vitamin, or it may predict whether or not there will be a benefit from a specific intervention, like lowering triglycerides. This way you can focus your efforts on those factors that will actually help.

This is an interesting approach – we just don’t know yet if this type of data will produce useful results.

A 2010 review by the Evaluation of Genomic Applications in Practice and Prevention (EGAPP) Working Group, specifically with relation to preventing heart disease, concluded:

The Evaluation of Genomic Applications in Practice and Prevention Working Group (EWG) found insufficient evidence to recommend testing for the 9p21 genetic variant or 57 other variants in 28 genes (listed in ) to assess risk for cardiovascular disease (CVD) in the general population, specifically heart disease and stroke. The EWG found that the magnitude of net health benefit from use of any of these tests alone or in combination is negligible. The EWG discourages clinical use unless further evidence supports improved clinical outcomes. Based on the available evidence, the overall certainty of net health benefit is deemed “Low.”

There is a great deal of basic science research going on (test tube and petri dish type research), which asks questions about how the body works and how it is affected by all conceivable factors. There is also translational or clinical research which seeks to apply this knowledge to specific medical interventions. Biology is horrifically complex, however, and so it is extremely difficult to extrapolate from basic science knowledge to net clinical effects. Most guesses that derive from basic science research turn out to be wrong. Sometimes our guesses are even the opposite of what we predicted – interventions cause harm rather than improvement. The only way to know is to conduct careful rigorous clinical research to measure the actual effects (good and bad) of a specific intervention in a specific population.

What the EWG is saying is that researchers have identified specific genetic types that do indeed affect metabolism and nutritional factors can influence gene expression, but the existing clinical data does not show a significant clinical effect. This is often what dooms very promising medical research – all of the science is correct and points in the direction that a specific intervention should have a specific benefit, but in the end the magnitude of the net clinical effect is tiny – too small to be worth all the trouble.

Further, because of the vast reservoir of published basic-science research it is possible to find studies that seem to support almost any conceivable intervention you wish. To the public this can make any intervention seem as if it is science-based and legitimate, even when the treatment is nothing but deception.

The nutrigenomics website, for example, claims to treat the following conditions:

Welcome to Genetics Based Integrative Medicine (GBIM), a telemedicine practice dedicated to the education, treatment, and recovery of those with autism spectrum disorders, ADD/ADHD, and PANDAS as well as highly complex & disabling disorders affecting adults such as CFS/ME/FM, Multiple Sclerosis, ALS, Parkinson’s and mitochondrial dysfunction.

There is no compelling evidence for any nutritional treatment for the above diseases, let alone for personalized nutritional treatment based on specific genetic types. How the practitioners of GBIM came by the knowledge they are claiming to have is a mystery. As with the prematurely promoted stem cell treatments, such clinical claims, if legitimate, would have a paper trail of hundreds of published studies in the literature. Further, if such studies existed such practice would be standard of care, not isolated to one or a few special clinics.

I would add “nutrigenomics” to the list of red flags for dangerous quackery. It is a shame because, like stem cells, it is a legitimate field of research, and the current quackery is likely to taint the reputation of what in the future might be a promising approach.

Posted in: Diagnostic tests & procedures, Nutrition

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4 thoughts on “Nutrigenomics – Not Ready for Prime Time

  1. Quill says:

    It is interesting to me that Brillat-Savarin’s famous quote “Tell me what you eat, and I will tell you who you are” is being reversed by these premature promotionists to “We will tell you who you are and then tell you what to eat.”

    What it all means to me is that cooking for a dinner party is about to become impossible. Just when I’ve navigated the culinary worlds of vegetarians, vegans, celiacs and various lethal allergies, now I’ll put a dish down and someone may exclaim “Oh! I can’t eat that! I’m a TT and I’ll overeat that and raise my cholesterol. Do you have anything for a tt, but no PTC, please?” Or something like that.

  2. yodeladyhoo says:

    I forced myself to sit still and watch a naturopath talk about cancer for a solid hour by video recently. I can’t resist sharing what i learned. This was a talk at cancer patients’ conference.

    Thanks to epigenetics, we can literally dial the volume of our genes up and down! We do gene therapy when we choose what foods to put in our bodies. And what we eat affects our progeny for three or four generations. Make sure you’re not working with a Registered Dietician — they know just enough to keep you from scurvy. Eat for your SNPs!

    I confess, I’ve ignored this stuff for years and am astonished at the depth of idiocy. It’s delivered aggressively and non-stop. Oncologists, please watch for patients who are seeing “naturopath oncologists.” They actually have “board-certified” specialty in oncology. (http://www.oncanp.org/) I hope the naturopath I’m hearing about is at the far end of extreme, but the “treatments” she’s recommending to individual patients are downright scary. This months’ favorite is get-your-body-into-ketosis-and-stay-there-forever.

  3. Jann Bellamy says:

    @yodeladyhoo:

    “I hope the naturopath I’m hearing about is at the far end of extreme, but the ‘treatments’ she’s recommending to individual patients are downright scary.”

    No, afraid not. It’s all right there in the 2012 edition of ND’s foundational text, “The Textbook of Natural Medicine,” Chap. 16 (“Genomics, Nutrigenomics, Nutrigenetics and the Path of Personalized Medicine”) and Chap. 50 (“Cancer — Integrated Naturopathic Support”).

  4. yodeladyhoo says:

    @Jann Bellamy

    Thank you for the reference! Much of the textbook is in Google books. I love this: “There is no evidence in the scientific literature to suggest that fasting itself can be considered a cause of death. Death during fasting indicates that the remedial efforts of the body have been overpowered by the pathologic process.”

    I would give a page reference, but I don’t see any page numbers (I found this when I searched the book for ‘ketosis.”)

    Maybe we should insist that naturopaths get their degrees from diploma mills and not attend schools where they would be required to read and memorize this stuff. I believe studying this would re-program one’s brain.

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