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The Overwhelming Evidence of the Healing Power of Food

The Overwhelming Evidence of the Healing Power of Food

THERE ARE NO STUDIES that prove the benefits of nutritional or integrative therapies … It’s a refrain that I hear time and time again. And I hear it from my colleagues. But they couldn’t be more wrong! They just have not done their homework — or perhaps they are reading the wrong medical journals.

One of my favorite medical journals is the American Journal of Clinical Nutrition, which every month publishes more than 300 pages of research with NO ADVERTISING. This is very unlike my other medical journals — such as the Journal of the American Medical Association or The New England Journal of Medicine — which have pages and pages of color glossy drug ads.

So today, I thought I would take you on a journey through just one issue of the American Journal of Clinical Nutrition to see just how much research is being done on how food and nutrients affect our health. The sad thing is that it can take 20 years before this knowledge becomes commonplace or used in medical practice.

Unfortunately, there is little money available for large-scale studies or to publicize the findings of the role of nutrients and food in health and disease.  Unlike in the pharmaceutical industry, there are no “food reps” that drop off food samples in doctor’s offices.

Except perhaps in my case.

You see, I have been sent walnuts, whole-food bars, wild salmon, and even whole-kernel rye bread from Germany — all of which I like much better than the pens and cups and Post-it notes with drug names all over them.

And I certainly like these better than the “free” drug samples I’m sent that are meant to get my patients hooked on the latest and most expensive (though not necessarily the best) medications. Advertising medications directly to patients used to be illegal. They still are in Canada and the European Union.

But, boy, have things changed!

Since “direct-to-consumer” advertising has been allowed in the United States, we have seen dramatic increases in the use of those drugs. In fact, when a person sees an ad for a drug on TV and then asks their doctor for it, they are likely to get it about 50 percent of the time.

If there were a drug that could turn off all the disease-promoting genes and could turn on all the health-promoting, anti-aging genes, it would be a blockbuster. But you don’t see ads on TV telling you to eat more whole-kernel rye bread!

Just look at the numbers.

According to a recent article in The New England Journal of Medicine, pharmaceutical advertising and promotion grew from $11.4 billion in 1996 to $29.9 billion in 2005 — and direct- to-consumer ads grew by 330 percent!  (1)

I can assure you that NO ONE is spending $30 billion promoting the benefits of food and nutrients to support health and cure disease, even if they are more effective. You don’t hear about the best or most effective treatments, just the ones that are most heavily promoted.

Now let’s get back to the nutrition journal and a sampling of the types of research out there that demonstrate the healing power of food. These are all from the May 2007 issue (I am a little behind on my reading!).

The most important study in that journal was on nutrigenomics — the foundational concept of my book UltraMetabolism.  The basic idea is that food is information, not just calories. In this study, researchers from Finland took two groups of people with metabolic syndrome (pre-diabetes) and gave each group a different diet.

Well, sort of. It was different ONLY in the type of carbohydrates they consumed for 12 weeks. The rest of their diet was identical — the same calories and the same amount of fat, protein, carbohydrate, and fiber.

The first group had wheat, oats, and potatoes as the source of their carbs.  The second group ate rye as their source of carbohydrate.   (As I mentioned in my book, UltraMetabolism, rye has some very special properties because it is slowly absorbed by the body and has phytonutrients that help you lose weight and improve metabolism).

After the 12 weeks, the researchers took a fat sample, or biopsy, and analyzed it to find out which genes were turned on or off.

So what happened?

In the wheat, oat, and potato group, 62 genes were activated that increased inflammation, oxidative stress, and the stress response, worsened blood sugar balance, and generally amplified all of the forces in the body that lead to obesity, heart disease, cancer, diabetes, and Alzheimer’s disease!

It was a 100 percent effect — NO good genes were turned on.

In the rye group, 71 genes were turned on that prevent diabetes, lower cholesterol, reduce inflammation, and improve blood sugar control. This was a 100 percent GOOD gene effect. (2) Now that should have been headline news — but the rye lobby is just not that powerful!

In fact, in an accompanying editorial called “Putting your genes on a diet: the molecular effects of carbohydrate,” Harvard researcher David Ludwig, MD, PhD, wrote that “Molecular pathways involved in hormone action have been the target of a multi-billion dollar pharmaceutical research effort.  However, many of these pathways may normally be under dietary regulation.” (3)

If there were a drug that could turn off all the disease-promoting genes and could turn on all the health-promoting, anti-aging genes, it would be a blockbuster.

But you don’t see ads on TV telling you to eat more whole-kernel rye bread! Findings from a few other key studies from just that one issue are worth noting:

— Supplementing with conjugated linoleic acid (a special fat from meat and dairy fats) caused a modest loss in body fat. It also may prevent cancer, heart disease, and inflammation.

— Long-term fish consumption protects against arrhythmia or irregular heart beats.

— Eating a diet high in monounsaturated fats from olive oil can help reduce blood pressure while a high refined-carbohydrate diet can increase blood pressure.

— Combining fish oil supplements with regular aerobic exercise helps improve body composition and reduce heart disease risk factors (lower triglycerides, higher HDL).

— Women need more choline (a nutrient that is needed for cell membrane formation and to make the neurotransmitter acetylcholine necessary for brain function) after menopause or are at risk of liver and muscle damage.

— If women with HIV are given a multivitamin, they have less anemia and their children also have less anemia.  Anemia in HIV is associated with a much faster rate of disease progression and death.

— In Bangladesh, where arsenic poisoning is common, giving folate, vitamins B12 and B6, choline, and niacin reduced the toxic effects of arsenic.

— People who eat more meat and saturated fat have a higher risk of skin cancer.

And those are just from May!

The June 2007 issue has a fantastic randomized controlled study of calcium and vitamin D, which shows that those nutrients substantially reduce risk for all cancers and that the blood level of vitamin D is the most important predictor of decreased risk.

So what are we to learn from all these studies?

This is just a smattering of the research out there — only a few out of the many in that one issue alone. And it is stuff you are not hearing about. So if you hear from your doctor that eating better and taking supplements has no “real” scientific evidence to support it, ask them if they have read the American Journal of Clinical Nutrition lately.

It is also interesting to note that the main medical journals publish mostly positive studies on drugs and mostly negative studies on nutrients, foods, and herbs. And the findings correlate 4 to 1 for a positive outcome for a drug if the study was funded by the drug company.

The same is true for nutrients. Dr. David Ludwig published a study that showed if a food company or industry, like dairy, for example, funded a study, there was a zero percent chance the outcome was unfavorable for the funder. But if it was independently funded, the negative outcomes were about 40 percent. (4)

That is exactly what happened in another study I saw on the effects of high fructose corn syrup. It showed no adverse effects — and was funded by the American Beverage Association.


So I encourage you all to beware when someone tells you there is no research to back up the use of food or nutrients as the primary mode of treatment of disease and prevention of chronic illness. The evidence is overwhelming — just ignored.

Now I’d like to hear from you…

How often do you hear about positive studies of food and nutrients? Of drugs?

Have you ever asked your doctor for a drug based on an ad? What happened?

Has your doctor — or someone else — told you that there’s no research to back up natural treatments like these?

Please leave your thoughts by adding a comment below – but remember, we can’t offer personal medical advice online, so be sure to limit your comments to those about taking back our health!

To your good health,

Mark Hyman, MD

(1) Donohue JM, Cevasco M, Rosenthal MB. A decade of direct-to-consumer advertising of prescription drugs.

(2) Kallio P, Kolehmainen M, Laaksonen DE, Kekalainen J, Salopuro T, Sivenius K, Pulkkinen L, Mykkanen HM, Niskanen L, Uusitupa M, Poutanen KS. Dietary carbohydrate modification induces alterations in gene expression in abdominal subcutaneous adipose tissue in persons with the metabolic syndrome: the FUNGENUT Study. Am J Clin Nutr. 2007 May;85(5):1417-27.

(3) Salsberg SL, Ludwig DS. Putting your genes on a diet: the molecular effects of carbohydrate. Am J Clin Nutr. 2007 May;85(5):1169-70.

(4) Lesser LI, Ebbeling CB, Goozner M, Wypij D, Ludwig DS. Relationship between funding source and conclusion among nutrition-related scientific articles. PLoS Med. 2007 Jan;4(1):e5

Mark Hyman MD is the Medical Director at Cleveland Clinic’s Center for Functional Medicine, the Founder of The UltraWellness Center, and a ten-time #1 New York Times Bestselling author.

Comments (6)

  • Dr. Mark….
    I just want to thank you for confirming things to me that I always ‘ knew “..even though I am NOT an expert/ a nutritionist or a Doctor; I have always known in my heart and soul that your food plan has a great bearing on ones health. I have even commented to a friend that her mothers bout with cancer could be less extreme if her mom would adopt healthier – and the RIGHT KIND of foods- eating habits. I so so appreciate all your information and I do try to get others acquainted with your insight and your objective of helping us all to choose a better food plan and eat the right kind of foods ! ~ Peace and Blessings to you..~ Shelby

  • I was very fortunate to find a Dr who believes food is medicine a few years traditional Gp daignosed me as diabetic (fasting sugars 7,4)….I embarked on a inrewnse excercise routine -and was given metformin and a dietician gave me a diet(still high in carbs)..I got soootired and still put on weight……then I went to Mel Sydney Smith…he tolds me I was starving my self fat!……he changed my diet to low carbs(bloos tests showed allergy to wheat,milk proteins)…
    lots of leafy veggies- protein and leafy veg every meal- supplements of Krill oil,Vitamin D3,chromium,cinnamon,bittermelon,magnesium did wonders to energy levels- also coconut cream and avacados promoted weight loss- internal visceral fat levels reducing..a salad dressing of olive oil and cider vinegar seemed to stabilise sugars..also..a supplement of 5HTP banished the period blues… metformin dose has been lowered-whilst my traditional gp wanted me to keep increasing it- she also said supplements were pointless! …I love your website- as finally I see a doctor who speaks sense!

  • So true! Here in Canada we have the same Government food guide that we had 20 years ago. Most of the information come from books written by doctors like you. My husband and I have the same doctor and all we had to do is ask him for a particular pill that we heard about on TV or other and he would prescribe it without comments, in some cases even giving us a free sample i.e. cyalis…he is a good doctor however he is quite young and not aware yet that so much has to do with nutrition, his medical training has thought him some strict procedure and on the long run he will probably learn from his patients that there are other causes to illness and other natural cures like food and exercises, acupuncture, yoga, meditation etc…, that is if he wants to hear us. When I was diagnosed with diabetes a little over a year ago, he immediately wanted to give me medication for it and high blood pressure pills as well, I decided to get on a strict diet with the help of the diabetic clinic and within a few months I saw you on PBS, ordered your book and the rest is history. I lost 27 lbs, have no health issue so far I am 71 years young….. 3 of my siblings have been through this, however they immediately took the pills, 2 had open heart surgery before they were 70, they take over 10 pills a day each, they are not well and my 75 year old sister is loosing her memory, lost her appetite, loosing her hair and at a 5 foot 3, weights 105 lbs. I think she has gluten intolerance as well, when her son asked the doctor for the test, she said maybe later and immediately prescribed her a anti depressor pill..(pill no. 15 for her).I don’t know if she had the thyroid gland test…. I’ll spare you the health conditions of the others..(pills and insulin) I knew that I didn’t want to go there. Thank you for spreading the information, I am also grateful to the doctors who are trying to change the world with gluten intolerance information and diets, my 77 year old sister had been so sick for 20 years because of gluten intolerance, she was loosing her sight, had severe arthritis, diarrhea, insomnia, depression and pills for every condition, the fact that we hear so much about it now, has made her ask her doctor for the test which clearly showed that she had a severe intolerance, she is a different person now and has a life againj. We have all the tools (food and exercises, supplements etc..) if we want to use them, the doctors should not worry about loosing their patients because they eat better and don’t want pills, but they should learn more about other venues and change their practice, maybe open some clinics to change things and I am sure they would have a good business along with their practice and save the government and us tax payers millions. Since nothing is perfect, unfortunately the pharmaceutical industry would decline and related jobs would be lost

  • I am simply amazed at the lack of nutritional knowledge in the medical community. Recently, I was diagnosed with acid reflux after my esophagus had to be ‘stretched’ via endoscopy. The doc immediately prescribed acid reducing medication and told me I would have to take it for life. Not once did we discuss my diet. Looking back, I cannot believe how absurd it was for a gastroenterologist to not even consider my diet, but rather prescribe medication that has long term side effects. I stumbled on a book, while not yours, and changed my life. I discovered that by not eating gluten, refined grains, sugar, and most dairy I have ZERO gastrointestinal issues. I stopped taking my medication and haven’t looked back. I wish nutrition was a mandatory part of the medical doctor curriculum.

  • I hear about healthy food all the time, but pretty much from you and the Daniel Plan, so I hear what you are saying. You are the doctor I have been dreaming of for years, that I have no idea how to find. I want a doctor that will look to natural remedies before pharmaceuticals, but how do you find someone like that? Whenever I research doctors all I get is where they studied, this information hardly tells me about their beliefs on health and healing. This is why I have to be grateful for the internet, even if it can’t help me to find my one GP, it can make good information more accessible. Thanks for providing the truth to those of us that are searching.

    Since starting the Daniel Plan I have lost 15 lbs and, for the first time ever, I feel like I understand and can continue to lose weight/eat healthy. Having grown up on frozen veggies, I am now creating a new love affair with fresh vegetables and am no longer ignoring veggies recipe, but am instead seeking out vegetarian ones. I have chucked out the acid reflux med (prantropozal) and instead am increasing my probiotic consumption and trying not to eat late . I have only been doing this for 2 days, but I’m excited that the acid reflux is minimal and I’m optimistic that your advise will help me to reverse this condition. Thanks for giving me hope and encouraging me towards good health!

  • Helo Dr Hyman! Thank you for that wonderful article on nutrigenomics. I like the information you gave about rye. I am gluten intolerant especially to rye….makes me ride the toilet train for 2 days 🙂 What other carbohydrates would you recommend for me to turn on good genes? Or to ensure if they are already turned on how to keep them turned on?