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Prenatal Multivitamins and Iron: Not Evidence-Based

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When I was pregnant, I obediently took the iron pills and prenatal vitamins prescribed by my obstetrician. And I prescribed them for every pregnant patient I took care of as a family physician. I never questioned the practice. It seemed intuitively obvious that it was a good thing; we know pregnancy makes extra nutritional demands and depletes iron stores. It never occurred to me to question what I had been taught, because it seemed perfectly logical. I did question other things I was taught that didn’t seem so logical. In my internship, we were ordered to do episiotomies on every patient (the rationale was that it made birth less traumatic for the baby and prevented uncontrolled perineal tearing in the mother). I was severely chastised for omitting an episiotomy on a patient who begged me not to do one. She had had several babies and was stretchy enough to deliver easily without an episiotomy. In this case, my common-sense clinical judgment was vindicated by further research in the years after my internship; new evidence showed that routine episiotomies were of no benefit, practice changed in response to the new evidence, and episiotomies are no longer done routinely.

That was a long time ago. I have long since learned that even the most reasonable assumptions can be wrong. I happened to be right about episiotomies, but I might just as well have been wrong; and the only way to know whether a belief is true is to test it in controlled scientific trials. As Will Rogers said, “It isn’t what we don’t know that gives us trouble, it’s what we know that ain’t so.” It turns out that routine multivitamin and iron supplementation is not supported by any convincing evidence from scientific studies. And practice is changing. Recently, when one woman asked her OB what she should do about prenatal vitamins he pulled his wastebasket out from under his desk and said “put them there.” (more…)

Posted in: Herbs & Supplements, Nutrition, Obstetrics & gynecology

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More Trouble for Antioxidants

Antioxidants are better acquired through food than pills.

Antioxidants are better-acquired through food than pills.

Antioxidants are now an iconic example of premature hype making its way into marketing and the public consciousness long before the science is adequately understood. There are multiple lessons to be learned in this story, and a new study just emphasizes those lessons further.

A brief history of antioxidants

One of the unavoidable consequences of metabolism (burning food for energy) is the creation of oxygen free radicals, or reactive oxygen species (ROS). These are molecules that are highly reactive. They essentially contain oxygen with an extra electron, which can react with another molecule, breaking bonds and causing damage.

As you might expect, the body has natural antioxidants which react with ROS to form benign molecules.

In the 1990s it became increasingly apparent that oxidative stress was playing an important role in cell damage, even sometimes triggering apoptosis, or programmed cell death. Many degenerative diseases, like Alzheimer’s disease, were shown to be driven in part by oxidative stress. In addition, it seemed that ROS play a role in aging.

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Posted in: Herbs & Supplements, Nutrition

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The Clean Eating Delusion

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While some parts of the world are concerned with eating, because of food insecurity, the “worried and well-fed well” are increasingly obsessed with so-called “clean eating.”

This is nothing new, but like every cultural phenomenon, it seems, has increased partly due to the easy spread of misinformation over the internet. If you are anxious about your health, and who isn’t to some degree, your anxiety is fed by a steady diet of pseudo-experts, con-artists, and internet personalities telling you about all the things you eat that adversely affect your health.

This phenomenon is increasingly being recognized as a health issue among experts. In 1996 Dr. Steven Bratman proposed a formal disorder he calls orthorexia nervosa. He writes:

For people with orthorexia, eating healthily has become an extreme, obsessive, psychologically limiting and sometimes physically dangerous disorder, related to but quite distinct from anorexia.

(more…)

Posted in: Nutrition

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The one thing you need to know before you detox

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New Year, New You, right? Here’s a perennially popular post, revised for 2016.

With 2016 upon us, it’s finally time get serious about your health. You’re resolving to eat better and exercise more. But first, you need to reset your body – and purge yourself of all of your lifestyle and dietary overindulgences. But how? The options seem limitless, and everyone has advice: There’s Dr. Oz, Gwyneth, and even your favourite Kardashian has advice: They’re all telling you how it’s essential to “detox”, “cleanse” and “flush” away all of your toxins. Your local pharmacy has an ever-growing section of products promising a newer, more pure you: supplements, homeopathy, ear candles, and an entire aisle of “detox kits” all promise to suck toxins out of your body. Don’t forget your local naturopath who sells IV vitamin drips as the detoxification solution to your problems. The approaches may differ but all the advocates are completely convinced of one fact: Detoxing will deliver a renewed body and better health. Not only will you look better, you’ll feel better. It is a new year. Wouldn’t a purification from last year’s habits (dietary and otherwise) of last year be the best way to start? Well before you pull out your credit card, there is one fact that “detox” advocates are reluctant to tell you. (more…)

Posted in: Health Fraud, Herbs & Supplements, Naturopathy, Nutrition

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Guess who pioneered chemoprevention through diet?

Listen to your science: Eat your vegetables.

This is an expansion of a post I did over on the Society for Science-Based Medicine blog about this time last year. The original post, which got far more traffic than is usual for the SFSBM, is a good example of how science works and the good that it can do. The hard work of real science illustrated here serves as a striking counterpoint to the slap-dash system of pseudoscience, which churns out fake diseases, causes, and cures by the dozen based on a fuzzy understanding of real science fueled by a healthy dose of imagination.

Naturopaths and “functional medicine” practitioners would have the public believe that they are the true experts on nutrition and health. Even though their nutritional advice contains a large serving of hooey and a big helping of dietary supplements, which they are happy to sell to patients.

So it was with great interest that I read the obituary of Dr. Lee Wattenberg in the New York Times.

Dr. Wattenberg published a landmark paper in the journal Cancer Research that reviewed 36 years of animal studies on the effects that certain compounds had on the development of cancer. The paper laid the framework for understanding how these compounds work. . . .

He showed that cabbage, brussel sprouts, cauliflower and broccoli inhibit the development of carcinogens. He isolated a compound in garlic that decreased “by a factor of three” the chances that animals injected with cancer agents would develop that cancer. He found two chemicals in coffee that neutralize free radicals, which are harmful chemicals commonly implicated in the onset of cancer.

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Posted in: Cancer, Herbs & Supplements, Naturopathy, Nutrition, Science and Medicine

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Intermittent Fasting

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Fasting can mean anything from total abstinence from food and beverages to restricting specific foods or the hours of food intake. Many religions have traditions of fasting, with various restrictions. There is a good summary of those traditions on Wikipedia. The reason for religious fasting is not to improve health, but for other reasons like improving discipline and demonstrating devotion.

There are many health claims for different fasting regimens. Daily calorie restriction has been demonstrated to prolong lifespans in several organisms, from yeast and worms to mice and monkeys, although the evidence for monkeys is equivocal and there is no evidence for humans. There is some evidence that intermittent fasting can forestall and even reverse cancer, cardiovascular disease, diabetes, and neurodegenerative disorders in mice. In humans, there is some evidence that it might help reduce obesity, hypertension, asthma, and rheumatoid arthritis. How good is the evidence? (more…)

Posted in: Nutrition

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Low Energy Sweeteners and Weight Control

artificial-sweetenersA new systematic review published in the International Journal of Obesity looks at the totality of evidence investigating whether consuming low energy sweeteners (LES), such as aspartame, sucralose, or stevia, is a net benefit or detriment for weight control. In addition to providing some clarity on the answer, the review also provides some insight into how different kinds of evidence address such questions.

LES vs sugar or water

The question may at first seem obvious – if you consume a beverage sweetened with an LES instead of sugar you will be avoiding up to several hundred calories. Those calories add up quickly. Twelve ounces of cola with sugar has 138 calories, for example. These are foods that people generally consume on a daily basis, and so avoiding these unnecessary calories should reduce total energy intake and help reduce or maintain weight.

The human body, however, is a complex system, as is human psychology, and so we have to consider the law of unintended consequences. It is possible, for example, that when people drink a diet beverage they feel they have earned the right to consume more calories elsewhere. This phenomenon is called compensation, and there is evidence for this effect.

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Posted in: Nutrition

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Breast Milk Testing: Scaremongering, Not Science

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New mothers, especially first-time mothers, tend to worry about whether they are doing what is best for their babies. A new service, Happy Vitals, will only add to those worries. We know that breast is best, but these folks make women question whether their breast milk is good enough. They say:

Happy Vitals provides families with the tools they need to monitor and improve the long-term health of their children. With our simple and easy-to-use tests, mothers can learn for the first time about the nutrient make-up of their breast milk, improve their diet and nutrition, and safeguard against exposure to heavy metals and other toxins that are harmful to a child’s growth and development.

After a crowdfunding/pre-sale campaign, they plan to start shipping kits this month. They offer various packages. For $149.95, they will analyze a sample of breast milk for four key nutrients: glucose, lactose, protein, and fat. For $559.95, they will also test for:

  • Four “indicators of immunity”: cortisol, IgA antibodies, IgG antibodies, IgM antibodies.
  • Eleven micronutrients: calcium, folate, iron, vitamin D, vitamin A, ferritin, magnesium, phosphorous, sodium, potassium, and vitamin B12.
  • Four heavy metal toxins: arsenic, lead, mercury, and cadmium (based on samples of infant’s hair and nails.)

(more…)

Posted in: Diagnostic tests & procedures, Nutrition

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Everything you always wanted to know about fermented foods 

Delicious homemade Kimchi (fermented cabbage). It's alive!

Delicious homemade Kimchi (fermented cabbage). It’s alive! Click for a closer look.

Fermented foods, such as sauerkraut and kombucha, have become popular for health reasons. I have made my own sauerkraut in the past and have recently made the tasty, fermented Korean side dish, kimchi. I did it not only for the taste but also for the hope that the bacteria responsible for the fermentation of the cabbage — lactic acid bacteria (LAB) — would contribute to the diversity of my gut microbiota.

As a research scientist in the field of bacterial pathogenesis, this made sense to me. Now that I have started blogging about health and fitness and have been writing more in depth articles about health related topics, I started wondering what research has been done on the health benefits of fermented foods. Can the bacteria in fermented foods even survive the harsh conditions of the human gastrointestinal (GI) tract, particularly the stomach?

I was amazed to learn that the fermentation of food has been used by humans for thousands of years as a way to preserve foods, and that the health benefits go beyond their microorganisms (don’t worry, citations are provided below). The fermentation process enhances the nutritional quality of food by contributing beneficial compounds such as vitamins, and by increasing the bioavailability of minerals. Probiotics, including those found in kimchi, have a range of positive effects on health, including the improvement of various intestinal inflammatory conditions, positive impacts on the immune system and even weight loss, and can alter the composition of the gut microbiome.

However, these effects mostly depend on whether the bacteria actually make it in sufficient numbers to the colon. And let me tell you, the journey to the colon is one harsh and dangerous ride!

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Posted in: Herbs & Supplements, Nutrition, Science and Medicine

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The Amarin case: off-label promotion and a double standard for prescription drugs vs. dietary supplements

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A recent court decision enjoined the FDA from threatening prosecution against a drug manufacturer for off-label promotion of a prescription drug. Based on this and an earlier decision by an appellate court, it appears that the FDA can no longer prosecute a pharmaceutical manufacturer for a truthful and non-misleading off-label promotion to health care professionals, at least within the jurisdiction of the United States Court of Appeal for the Second Circuit, which covers Connecticut, New York and Vermont.

For this reason, the case, Amarin Pharma, Inc. v. FDA (Amarin), received a good deal of attention in the world of drug regulation. (Here is an excellent analysis by two attorneys who practice in the area of drug regulation.) First, we’ll take a look at the issue of off-label promotion. Then we’ll look at an issue that really didn’t engender much comment, but that I find fascinating: how the same substance can be subject to very different regulatory treatment, depending on whether it is sold as a dietary supplement or prescription drug.

Background: Initial approval of Vascepa and subsequent research

In 2012, the pharmaceutical manufacturer Amarin received FDA approval for a new drug, Vascepa, as an adjunct to diet to reduce triglyceride levels in adult patients with severe hypertriglyceridemia (triglycerides ≥ 500mg/dL). Approval was based on a single phase 3 clinical trial.

Following that approval, Amarin designed a second single phase 3 clinical trial to look at the effect of Vascepa on triglyceride levels among statin-treated patients with persistently high triglycerides (≥ 200 and ≤ 500 mg/dL). Pursuant to an agreement with the FDA that, if it met certain conditions, Vascepa would obtain approval for this use, Amarin proceeded with an FDA-approved protocol. As a further condition of the agreement, it also began enrolling patients in a third trial to see if Vascepa actually reduced major cardiac events. (more…)

Posted in: Clinical Trials, Herbs & Supplements, Legal, Nutrition, Pharmaceuticals, Politics and Regulation

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