It Starts With Food: A Critical Review Introduction

Following my review? See an up-to-date list of the chapters I've tackled here.

I am going to fact check the claims made in It Starts With Food by reviewing all 450+ citations provided by the authors. Got your attention? Good, keep reading.

That Was Then

I was introduced to the Whole30 by way of my CrossFit gym (yes, I’m a cult member. Leave me be!). Like many other CrossFit gyms, they offered a paleo-centric nutrition program. For the program, you had to read through the Whole30’s book, It Starts With Food (ISWF), as well as various other texts about the importance of sleep, nutrition, etc. The program lasted 60 days and was a stricter version of what is prescribed by ISWF. On the traditional program, they essentially get you down to eating meat, veggies, fruits, and nuts for 30 days. At my Crossfit gym, we got down to eating meat, veggies, and some nuts during weeks 6-8. It was tough. The purpose of the program was three-fold:

  1. Have people foster a healthy relationship with food

  2. Break bad food habits/cravings

  3. Get participants to eat healthier

My friends that were on it lost a ton of weight. The average weight loss for men seemed to be about 30 lbs. (13.6 kg) over two months. Granted, some of this would have been water weight loss due to the low carb nature of the diet. People felt great, they slept better and talked about how much more energy they had. I even saw improvements in some of my metabolic markers.

Side Note: I started eating like crap the weeks before I started the Whole30. I gorged myself on all the delicious foods I was about to cut out of my diet so my "Before" numbers may not be a representative baseline. 

At the time, I thought this was a pretty good, if albeit drastic, program to get people eating better. The Whole30 was never meant to be sustainable but rather a catalyst to get you to change your food habits in the long run. At the end of the program, you are supposed to start reintroducing foods that were forbidden during your 30-day diet such as grains, beans, dairy, and so on. Essentially, the foods that are excluded from the typical Paleo diet.

This Is Now

That all took place in 2013. At the end of that year I began my formal education in nutrition and kinesiology at George Mason University and obtained the CISSN and PN nutrition certifications. Up until that point, my education in nutrition had consisted of reading some popular blogs and various books on nutrition and diet. Once I started at GMU, my readings shifted towards published journal articles and textbooks which helped to greatly improve my comprehension of nutritional science. During that time, I started to notice some very odd posts popping up on the Whole30 Facebook page. These posts were either highly misleading, poorly researched or flat out wrong.  Here are three examples of what I'm talking about. 


It’s pretty evident that the author either did not read or comprehend the paper he cited [1]. Organic food has never conclusively been shown to be more nutritious or contain less harmful pesticide residues. There have been 5 recent meta-analyses showing no clinically relevant nutritional differences between organic and conventional produce [2,3,4,5,55].

Consequently, the USDA announced in 2013 that there will be mandatory testing of organic produce for pesticide residue for the first time ever [6]. The pilot program results were published last year if you want to take a look [7]. Currently, there are ~40 pesticides allowed in the production of organic food [8]. Regardless of the production method, you would have to eat an insane amount of food to ingest a level of pesticide that would actually cause harm [9]. 


Repeat after me, “detox diets are not a thing”. Do you have a functioning liver? Congratulations, your body is officially detoxified. Whenever you see someone trying to sell you a ‘detox’ program be sure to ask them the following questions:

  1. What specific ‘toxin(s)’ are you eliminating and by which mechanism will you eliminate them?

  2. What is the evidence that they are damaging to my health and at what levels?

  3. What tests are being used to measure these toxins and what is their validity and reliability?

  4. What randomized controlled trials have been performed demonstrating the effectiveness of your detox program?

Detox diets have been debunked ad nauseam so I won’t delve into the nitty gritty here but if you would like some further reading into the pseudoscientific nonsense of 'detox', peruse some of the links below.

“At present, there is no compelling evidence to support the use of detox diets for weight management or toxin elimination” - Detox diets for toxin elimination and weight management: a critical review of the evidence.

Alternative Detox – British Medical Bulletin

Harvard Health - The Dubious Practice Of Detox

WHO - State of the science of endocrine disrupting chemicals (2012)

Read This Before You Start A Detox Diet Plan

The Detox Delusion

SBM – Detox

SBM – Detoxification


Have you ever been at a party where someone brings up a topic in which you are fairly knowledgeable and it quickly becomes evident that said person has no idea what they’re talking about? That’s how I felt when reading this post. It made me want to bang my head on my desk (#headdesk). I’m also 99% certain that Dallas (one of the authors of ISWF) did not read and/or comprehend the study the Reuters article is referring to (we’ll cover what it said in a bit). There’s so much misinformation in Dallas’s statement we’re going to have to take this line by line. 

But first, you need to understand how the International Agency for Research on Cancer (IARC), the cancer research arm of the WHO, classifies carcinogens. Here is their classification system:

  • Group 1: Carcinogenic to humans

  • Group 2A: Probably carcinogenic to humans

  • Group 2B: Possibly carcinogenic to humans

  • Group 3: Unclassifiable as to carcinogenicity to humans

  • Group 4: Probably not carcinogenic to humans

Glyphosate got classified as a Group 2A carcinogen. For perspective, alcohol is a Group 1 carcinogen. To understand what that means, go watch this video and then come right back.

I’ll wait.

You’re back! Let’s get started. 

“Glyphosate, the active ingredient in Roundup, is the world’s most widely used weed killer”


“ … and is sprayed heavily on crops such as corn and soybeans”

Heavily? Wouldn't a farmer just spray what is needed as opposed to unnecessarily over-spraying his crops? Concentrated Roundup is not cheap and overusing it would cost the farmer more money.

“[Glyphosate] has been found in air, water, and soil in agricultural areas.”

“Other research that I have read has found glyphosate residues in the food crops themselves”

So has aluminum [10,11]. What is his point? He seems to be implying that glyphosate found at any level is somehow dangerous. I’ll spare you the Paracelsus quote, but just this once!

“In the case of massive application of herbicides like roundup, the toxicity of the chemicals must also be taken into account if there is a residue left in the food itself.”

Let’s discuss the toxicity of glyphosate. The pathway (the Shikimate pathway) through which Roundup (glyphosate) acts on Roundup Ready plants does not exist in humans [12,13]. The lack of this pathway in humans is one of the reasons why glyphosate has a relatively low toxicity. For some perspective, here’s a nifty chart comparing the toxicity of glyphosate to other common substances [14-21].

For further comparison here’s a table of the toxicity classification of pesticides approved in organic farming. 

Does any of this really matter? Not in terms of the residue that ends up on your food. The USDA’s Pesticide Data Program closely monitors levels of pesticide residue on our food. In 2013, only 0.27% of all produce tested exceeded the Allowable Daily Intake (ADI) levels [22]. 40.5% had no detectable traces of pesticide whatsoever [22].

Dallas continues:

“It is not just the genetic engineering that is the potential problem.”

“My opinion is that glyphosate toxicity is just as large or larger of a problem as any specific genetic modifications.”

There is a big disconnect between the public perception of GMO’s and the scientific facts. A recent poll published by the PEW Research Center found that only 37% of US adults thought eating GMO foods was safe compared to 88% of scientists.

Nearly every single major independent scientific body has come out in support of the safety of GMO foods. Even the WHO, whose research sparked the above post from Dallas, has stated the following,

“GM foods currently available on the international market have passed safety assessments and are not likely to present risks for human health. In addition, no effects on human health have been shown as a result of the consumption of such foods by the general population in the countries where they have been approved” [26].

To give you an idea of just how broad the consensus is on the safety of GM food, here is an infographic from all the scientific bodies with position statements on GMO’s [23-45].

“The good news is that Roundup is not typically used on any of the nutritious vegetables and fruit that I recommend eating.”

True, but what about the other 40 pesticides approved for organic agriculture?

The IARC Paper

Let’s take a look at the study that inspired Dallas’s post and what it actually said. 
Here is the breakdown of the paragraph in the paper pertaining to glyphosate (emphasis mine) [46].

“There was limited evidence in humans for the carcinogenicity of glyphosate. Case-control studies of occupational exposure in the USA [47] Canada [48] and Sweden [49] reported increased risks for non-Hodgkin lymphoma that persisted after adjustment for other pesticides. The [large] Agricultural Health Study (AHS) cohort did not show a significantly increased risk of non-Hodgkin lymphoma.”

So in observational human trials the evidence for glyphosate carcinogenicity is weak or not correlated. 

“In male CD-1 mice, glyphosate induced a positive trend in the incidence of a rare tumor, renal tubule carcinoma. A second study reported a positive trend for hemangiosarcoma in male mice [50]. Glyphosate increased pancreatic islet-cell adenoma in male rats in two studies. A glyphosate formulation promoted skin tumors in an initiation-promotion study in mice.”

Keep in mind that these mice only saw these cancers appear after ingesting huge amounts of glyphosate. In the rats that had renal tubule carcinoma, they were being dosed at 590 or 850 mg/kg body weight (bw) [50]. The male mice that developed haemangiosarcoma were being dosed at 1,000 mg/kg bw and those that saw increased pancreatic islet-cell adenoma were dosed at 236 mg/kg bw [50].

These are all doses that you would not be able to reach through consumption of food. An average adult male could consume 2,640 servings of strawberries or 12,626 servings of potatoes in one day without any adverse effects even if the produce contained the highest pesticide residue ever recorded by USDA [9]. And it’s always important to remember that these are animal studies which are good models but not exact replicas of what happens in a human.

“Glyphosate has been detected in the blood and urine of agricultural workers, indicating absorption. Soil microbes degrade glyphosate to aminomethylphosphonic acid (AMPA). Blood AMPA detection after poisonings suggests intestinal microbial metabolism in humans.”

Yes, there are detectable levels of glyphosate in agricultural workers. Those that may be spraying these chemicals are going to have a much higher exposure to any pesticide and need to take precautions such as wearing protective gear to reduce their exposure. The agricultural exposure to pesticides is not related to the minimal amount of pesticide we encounter in our food. That topic was not even covered in the paper. 

“Glyphosate and glyphosate formulations induced DNA and chromosomal damage in mammals, and in human and animal cells in vitro. One study reported increases in blood markers of chromosomal damage (micronuclei) in residents of several communities after spraying of glyphosate formulations [51] Bacterial mutagenesis tests were negative. Glyphosate, glyphosate formulations, and AMPA induced oxidative stress in rodents and in vitro. The Working Group classified glyphosate as “probably carcinogenic to humans” (Group 2A).”

Chromosomal damage sounds scary, but when you read the paper the IARC cited the authors concluded that:

“A statistically significant increase of MOMN was observed in Boyacá and Valle del Cauca before and after the aerial spraying, suggesting exposure to other genotoxic compounds in these populations was independent of the exposure to glyphosate. Evidence indicates that the genotoxic risk potentially associated with exposure to glyphosate in the areas where the herbicide is applied for eradication of coca and poppy is of low biological relevance.” [51]

For further reading on the IARC’s paper, check out some of the following links.

Does Popular Herbicide Glyphosate Cause Cancer? Probably Not

Glyphosate Causes Cancer - So Do Apples

Glyphosate and Cancer: What does the data say?

Glyphosate As A Carcinogen, Explained

So Roundup “probably” causes cancer. This means what, exactly?

Is Glyphosate Probably Carcinogenic? Probably Not!

Chronic Misinformation

The posts examined above are not just one-off occurrences. These kinds of factually challenged posts happen with some regularity on their Facebook page.

Luckily, their members were able to point out how misleading this article was. 

Dallas Hartwig, MS, PT, CISSN, RKC

  • BS in Anatomy & Physiology from Andrews University in 2000

  • MS in Physical Therapy in 2001

  • Certified Strength & Conditioning Specialist in 2003

  • On the Advisory Board for Paleo f(x) and the Athletic Advisory Board for Fitwall

  • On the Board of Editors and Reviewers for the International Journal of Human Nutrition and Functional Medicine (IJHNFM).

  • Founded his functional medicine practice [in 2012], “mentoring under Dr. Daniel Kalish and enrolling in the Institute for Functional Medicine's certification program” (IFMCP)

    • Completed a functional medicine internship at “the Kalish Institute as well as completing the advanced Mind Mapping training module” before enrolling in IFMCP

So it looks like Dallas has a solid background in human physiology, physical therapy, and strength training. No formal training in the disciplines such as nutrition or behavior change but that’s neither here nor there I guess. As long as he is accurately communicating the concepts from these fields in the book he should be good to go. 

Next I went looking into the International Journal of Human Nutrition and Functional Medicine (IJHNFM). It was not indexed by PubMed or the Master Journal Lists. Because there are a lot of junk journals out there it’s important to check these two sources to help weed out the less rigorous ones. Since the IJHNFM is not listed by either of these services, it’s a good indication that it is not a high-quality journal. But again, it doesn’t mean the information in ISWF isn’t correct. 

UPDATE (5/13/2015) - I had emailed the IJHNFM to confirm Dallas was an editor/reviewer there because there's no mention of him on the site. Their Chief Director and Editor confirmed that he was and then oddly offered me a position as a reviewer/editor for their journal. Didn't ask for my resume, credentials, CV or any additional information of any kind. These kinds of actions do not happen in reputable journals and confirms my earlier suspicions that this is a very low quality publication. You can read the whole email exchange here

Things start to get weird when I looked into the Institute for Functional Medicine (IFM). In 1993, Jeffrey S. Bland, Ph.D. founded the IFM. Bland and the companies he manages have had a colorful history with the FTC and FDA [52]. They have been in trouble for making unsubstantiated claims about the supplements they sell over and over and over and over and over

Dr. Mark Hyman, MD, who is the chairman of the IFM Board of Directors, is well known for pushing pseudoscientific remedies such as detox diets and homeopathy. For the uninitiated, homeopathy is the mother of all medical quackery and has no basis in reality. A while back, I decided to pull one of Dr. Hyman’s articles and reviewed his sources. Not a single paper he cited supported the claims he was making.

Not. Even. One

His soft relationship with science has been noted by many. 

PBS’s latest infomercial

Bill and Hillary Clinton go woo with Dr. Mark Hyman and “functional medicine”

Dr. Mark Hyman: Let’s turn back the clock on science-based medicine in favor of anecdote-based medicine

Dr. Mark Hyman mangles autism science on–where else?–The Huffington Post

Mark Hyman: Mangling cancer research and systems biology in the service of woo

Mark Hyman deceives about “science research deception”

The certification that Dallas is pursuing is another story. The Institute for Functional Medicine's Certification Program (IFMCP) requires the following to become an IFM Certified Practitioner [53,54]:

  • Applying Functional Medicine in Clinical Practice (AFMCP) course (5 Days On-Site Training | $3,000)

  • All six individual Functional Medicine Advanced Practice Module (2.5 Days On-Site Training Each | $1,800 apiece)

    • GI

    • Detox (not a thing!)

    • Immune

    • Hormone

    • Cardiometabolic

    • Energy Regulation

  • Passing score on one case report ($800)

  • Passing score on the IFMCP written examination ($800)

  • Must be completed within 7 years from an approved application

So with $15,400, 20 days of training, and two exams later you are now an IFM Certified Practitioner. But what does that get you? Well, the IFM certification is not recognized by any reputable certification or medical body and their program “does not confer any additional legal or professional specialty”.

On top of all of that, functional medicine is not a regulated term (meaning anyone can call themselves a functional medicine practitioner) and the field does not have the best reputation for being scientifically rigorous as its practitioners frequently make claims laced with half-truths and pseudoscientific theories like detox, homeopathy, and pushing anti-vaccine viewpoints. The quote below encapsulates many of the issues with the field of functional medicine. 

“Alternative medicine is a collection of things we don’t know work and things we know don’t work.”

Currently, Dallas is AFMCP certified and I am assuming on his way to becoming an IFM Certified Practitioner. UPDATE (1/8/2018) - Dallas is no longer listed on the IFM website as a practitioner. I suspect he may have lost interest in maintaining the certification and let it lapse.

You can find details about his functional medicine practice here. 

Melissa Hartwig, CISSN, RKC

  • Featured in the Wall Street Journal, Details, Redbook, and Woman’s World magazines, as well as on the Dr. Oz Show, Good Morning America, and Nightline

  • Presented more than 200 health and nutrition seminars worldwide

  • On the advisory board for Paleo Magazine

  • Ambassador for Lolë

  • Masters of Science in Health and Nutrition Education (MHNE) at Hawthorn University (2011–2015)

Everything seems all well and good until that last bit. Hawthorn University is an online program and is not accredited by any organization recognized by the US Department of Education. Here are the current classes required for the MHNE.

Things Get Strange

In June of 2014, the Whole30 had a post on their Facebook page calling Dr. Oz one of the “most famous promoter[s] of diet scams in the United States".

Later that year, the Whole30 made an appearance on Dr. Oz.

That seems like a pretty abrupt about face. The Hartwig’s posted a statement saying that it was worth going on the show because it was more important to get the message of the Whole30 program out to the people regardless of the platform. 

Whatever their reasoning, their decision to appear on Dr. Oz was a business one more than anything else. It certainly paid off in the end as their Google traffic saw a huge increase after the show aired. Since then, Dallas and Melissa have made additional appearances with the “most famous promoter[s] of diet scams in the United States". Birds of a feather, or something like that.

Why Am I Doing This

Because of the sketchy Facebook posts and dubious educational background of the authors, I have become highly skeptical of their ability to accurately interpret and convey scientific research to the public. But that is not all. In the years since doing the Whole30 program, I’ve seen my friends go through many weight cycles on this diet. They lose weight on the program, slowly gain it back once it’s over, and then go through another program to lose the weight again. The critical message of how to build a sustainable diet for weight maintenance and general health is getting lost somewhere along the way. So, from a personal standpoint, I want to know if the information being given to my friends and family by the Hartwigs is measured, well-researched, and representative of the current body of evidence in the areas they discuss (Update: It's not). And they discuss a lot of areas. At first glance, they touch on the following disciplines:

  • Behavior Change

  • Endocrinology

  • Epidemiology

  • Food Addiction

  • Gastroenterology

  • Lipidology

  • Neurology

  • Nutritional Science

  • Obesity Research

  • Oncology

  • Psychology

I’m hoping that the Hartwigs reached out to people knowledgeable in the above fields but I don't know for sure. Lord knows it’s challenging enough to become an expert in one field, let alone 11! I’ll be reaching out to experts while reviewing their book, but I also call upon you, the reader, to help correct mistakes where you see them. 

Let us begin and may the Science be with you.







  6. (Federal Register Volume 77, Number 218 (Friday, November 9, 2012))

  7. (2010 – 2011 Pilot Study Pesticide Residue Testing of Organic Produce)

  8. (ELECTRONIC CODE OF FEDERAL REGULATIONS | Title 7 → Subtitle B → Chapter I → Subchapter M → Part 205 → Subpart G)


  10. (WHO FOOD ADDITIVES SERIES: 65 Safety evaluation of certain food additives and contaminants)

  11. (Aluminum has been evaluated for acceptable daily intake by the Joint FAO/WHO Expert Committee on Food Additives on numerous occasions.)











  22. (Pesticide Data Program’s (PDP) 23rd Annual Summary for calendar year 2013)


  24. AAAS (October 2012) Statement by the AAAS Board of Directors On Labeling of Genetically Modified Foods, Available online at:

  25. AMA (2001) Bioengineered (Genetically Engineered) Crops and Foods, Available online at:

  26. WHO (2012) 20 questions on genetically modified foods. Available online at:

  27. NAS (2004) Safety of Genetically Engineered Foods: Approaches to Assessing Unintended Health Effects. Available online at:

  28. RSM (2008) Genetically modified plants and human health, Available online at:

  29. EC (2010) A decade of EU-funded GMO research. Available online at:

  30. ACSH (2000) BIOTECHNOLOGY AND FOOD. Available online at:

  31. ASPB (Date Unknown) Statement on Plant Genetic Engineering. Available online at:

  32. ASCB (Date Unknown) ASCB Statement in Support of Research on Genetically Modified Organisms. Available online at:

  33. ASM (2000) Statement of the American Society for Microbiology on Genetically Modified Organisms Available online at:

  34. CSSA (2001) CSSA PERSPECTIVE ON BIOTECHNOLOGY. Available online at:

  35. WSF (2005) Genetically Modified Crops and Plant Breeding. Available online at:

  36. CAST (2005) Crop Biotechnology and the Future of Food: A Scientific Assessment. Available online at:


  38. IAS () Position statement on biotechnology. Available online at:

  39. FASS (date unknown) FASS Facts: On Biotech Crops – Impact on Meat, Milk and Eggs. Available online at:

  40. 14 Italian Science Organisations (2004) Sicurezza alimentare e OGM: Consensus Document. Available online at:

  41. SOT (2003) The Safety of Genetically Modified Foods Produced through Biotechnology. Available online at:

  42. TWAS (2000) Transgenic Plants and World Agriculture. Available online at:

  43. FAS (2002) Les plantes génétiquement modifies. Available online at:

  44. UDDADW (2006) InterAcademy Panel Initiative on Genetically Modified Organisms. Available online at:

  45. ISCU (2003) New Genetics, Food and Agriculture: Scientific Discoveries – Societal Dilemmas. Available online at:





  50. (Pesticide residues in food - 2004 Joint FAO/WHO Meeting on Pesticide Residues)