by Marion Nestle

Currently browsing posts about: Vitamins

Nov 28 2014

Weekend reading: Vitamania!

Catherine Price.  Vitamania: Our Obsessive Quest for Nutritional Perfection.  Penguin Press, 2015.

I blurbed this one:

Catherine Price gives us a journalist’s entertaining romp through the fascinating history of the discovery of vitamins, and their use and marketing as objects of health obsession.  Faith in vitamins, she advises, should be tempered by scientific uncertainty and dietary complexity, and the understanding that foods are better sources than pills.

This is the second excellent book I know of with that title.  This one came out in 1996.  It focused on supplements and their marketing.

Both have interesting things to say about why so many of us take vitamin supplements, regardless of the lack of evidence that they do us much good.

As I keep observing, there just isn’t much evidence that vitamin supplements make healthy people healthier.

Dec 23 2013

Alas, the bad news on dietary supplements continues

Over the weekend, the New York Times carried a front-page story about liver damage caused by an herbal supplement advertised as a “fat burner.”

It pointed out that as a result of a 1994 act of Congress, such products are virtually unregulated.  No federal agency pays much attention to their contents or claims, and Congress only lets the FDA take action against them after they are found to be harmful.

Fortunately, vitamin and mineral supplements rarely cause harm.  But the question of whether they do any good continues to trouble researchers.   As NutraIngredients_USA summarizes the latest rounds of research,

Stop wasting money on supplements, say physicians. Stop trying to position supplements as cures for disease, say industry groups.  An editorial panel of medical doctors (MDs) says the case is now closed for multivitamins: they don’t help well-nourished adults. But leading trade associations have defended the safety and efficacy of the products, calling the editorial, ‘close-minded, ‘one-sided’ and ‘overblown.’

The article refers to studies published in a recent issue of the Annals of Internal Medicine.  These showed that multivitamin supplements did nothing to prevent heart attacks or cancer, or improve cognitive function.

This led to an editorial entitled:

Its conclusion: Most multivitamin supplements do no good; some may do harm.  If you are healthy, you don’t need them.

Not that this will stop anyone from taking them….

 

 

Nov 14 2013

The dismal news about supplements. Why bother?

It’s not a good time for the makers of herbal and vitamin supplements.  The better the research, the fewer benefits it shows.

Herbal supplements

DNA testing is demonstrating what many of us have long suspected: herbal supplements are not necessarily what they say they are.

As the New York Times reports, a recent study shows that many products purporting to be herbal supplements, actually contain rice, corn, or wheat (gluten-sensitive folks beware):

I would feel sorry for supplement manufacturers, if they hadn’t brought this on themselves.

First, they lobbied to get Congress to pass the Dietary Supplement Health and Education Act of 1994 (DSHEA).  This lets them advertise the benefits of supplements without much in the way of scientific substantiation.  It also excused the FDA from doing much regulation.

But DSHEA also required research.  Oops.   Although the point of asking for research was to demonstrate the benefits of supplements, things haven’t worked out that way.  Most of the research shows no benefit and, sometimes, harm.

And investigations like this one show what many have long suspected.  Without federal oversight, some supplement manufacturers will do whatever they can get away with.

Fortunately, rice substituted for St. John’s Wort is harmless and hardly matters, since St. John’s Wort doesn’t seem to do much anyway.

Vitamin Supplements

The latest review of the benefits—or lack thereof—of vitamin supplements for prevention of heart disease or cancer comes to cautious conclusions.

Limited evidence supports any benefit from vitamin and mineral supplementation for the prevention of cancer or CVD. Two trials found a small, borderline-significant benefit from multivitamin supplements on cancer in men only and no effect on CVD.

Borderline significance?  Not impressive.

The Natural Products Association, which represents supplement makers, issued a response:

  • Multivitamin supplements should not be expected, without the combination of a healthy lifestyle, to prevent chronic disease.
  • Dietary supplements are used by more than 150 million Americans on a daily basis. Research has shown that when taken in combination with other healthy lifestyle practices, such as consuming a wholesome diet and exercising regularly, people can benefit from dietary supplements.

Translation: if you consume a wholesome diet and exercise regularly, you really don’t need supplements.  And if you are not doing those things, supplements won’t do any good.

As for the 150 million Americans who take supplements: the ones I know tell me that they don’t care what the science says; they feel better when they take the pills.

Let’s hear it for placebo effects!

Aug 26 2013

FDA study: Do added nutrients sell products? (Of course they do)

The FDA has announced that it will be studying the effects of nutrient-content claims on consumers attitudes about food products.

FDA does not encourage the addition of nutrients to certain food products (including sugars or snack foods such as [cookies] candies, and carbonated beverages). FDA is interested in studying whether fortification of these foods could cause consumers to believe that substituting fortified snack foods for more nutritious foods would ensure a nutritionally sound diet.

Here’s one of my favorite examples of what the FDA is talking about.

New Picture

 

I’m guessing the FDA’s new research project is a response to increasing pressure from food companies to be allowed to add nutrients to cookies, candies, and soft drinks.

Food marketers know perfectly well that nutrients sell food products.  The whole point of doing so is to be able to make nutrient-content claims on package labels.

The FDA has never been happy about the practice of adding nutrients to junk foods just to make them seem healthy.   Its guidance includes what is commonly known as the “jelly bean rule.”   You may not add nutrients to jelly beans to make them eligible to be used in school lunches.

But this does not stop food manufacturers—especially soft drink manufacturers—from trying.  Hence: Vitamin Water (now owned by Coca-Cola).

Plenty of research demonstrates that nutrients sell food products.  Any health or health-like claim on a food product—vitamins added, no trans fats, organic—makes people believe that the product has fewer calories and is a health food.

As I keep saying, added vitamins are about marketing, not health.

Jan 30 2013

Cookies are health foods!

What is there to say about Girl Scout cookies.  Everybody loves them (or is forced to).

But now, if you worried that promoting cookies maybe wasn’t the best public health strategy, ABC Bakers, the company that makes them, has solved your problem.

Girl Scout cookies are now health foods.  How?

NutriFusion.

Translation: “major vitamins.”

Mango Creme cookie

As the company explains, NutriFusion is delicious made nutritious.

These crunchy vanilla and coconut cookies with a mango-flavored crème filling have all the nutrient benefits of eating cranberries, pomegranates, oranges, grapes, and strawberries.

As I keep saying, you can’t make this stuff up.

Jan 28 2013

Some views on vitamin supplements, mostly from their makers

NutraIngredients.com reports frequently on current research and opinion on dietary supplements.  Lots of people take these products and swear by them, but proving that they do much good is another matter.  It has been hard to find evidence that they make healthy people—those who take them most often—any healthier.

Here are some recent NutraIngredient reports on this topic, largely reflecting views of the supplement industry.

May 1 2012

Nutritionist’s Notebook: Estimating nutrient requirements

My Tuesday question from student readers of NYU’s Washington Square News:

Question: How can we determine our individual caloric, vitamin, carbohydrates, fats and other intake requirements per day based on our own individual weight, height and lifestyle?

Answer: You can’t. You will have to be satisfied with estimates based on measurements performed years ago on a small number of study subjects.

We require calories and nutrients — 40 to 50 separate substances that our bodies cannot make, we must get from food. Because these interact, studying one at a time gives results that may well be misleading.

Early nutrition scientists got “volunteers”— in quotes because study subjects often were prisoners — to consume diets depleted in vitamin C, for example. They waited until the subjects began to develop scurvy, a sign of vitamin C deficiency. Then they fed the subjects the smallest amount of vitamin C that would eliminate symptoms.

Because individuals vary in nutrient requirements, scientists used this data to estimate the range of nutrient intake that would meet the needs of practically everyone.

The Institute of Medicine compiles such data into Dietary Reference Intakes and presents the estimates by sex and age group. You can look up your requirements in DRI tables. DRIs account for the needs of 98 percent of the population. If your requirements are average, you will need less.

Few American adults show signs of nutrient deficiencies, but if you are worried about your own intake of nutrients, you can take a multivitamin supplement. Note, however, that we have no evidence to show supplements make healthy people healthier.

You can estimate calories by looking up everything you eat or drink in food composition tables, but it is easier to weigh yourself at regular intervals. If you are gaining weight, you are eating too many calories for your activity level.

With nutrition, it’s best to get comfortable with estimates and probabilities.

Fortunately, eating a healthy diet takes care of nutrients without your having to give them a thought. Eat your veggies!

A version of this article appeared in the Tuesday, May 1 print edition. Marion Nestle is a contributing columnist. Email her questions at dining@nyunews.com.

Nov 30 2010

IOM: vitamin D, calcium supplements not needed!

In a report likely to send shock waves through the dietary supplement industry, the Institute of Medicine (IOM) released new Dietary Reference Intakes for vitamin D and calcium.   The report summary says Americans are getting all the vitamin D and calcium we need, and we do not need more.

The committee emphasizes that, with a few exceptions, all North Americans are receiving enough calcium and vitamin D. Higher levels have not been shown to confer greater benefits, and in fact, they have been linked to other health problems, challenging the concept that “more is better.

In an account of the report in today’s New York Times, Gina Kolata writes that the committee was puzzled about how vitamin D became the hot nutrient of the year.  Sales rose 82% from 2008 to 2009.

Some of this surely had to do with testing.  A method for testing existed, so doctors used it.  The test, however, looked at an intermediate in vitamin D synthesis—not at the vitamin itself.  And the test did not have a standard until recently.

And groups like the Vitamin D Council promote much higher intakes of vitamin D supplements.  According to the Council:

Current research has implicated vitamin D deficiency as a major factor in the pathology of at least 17 varieties of cancer as well as heart disease, stroke, hypertension, autoimmune diseases, diabetes, depression, chronic pain, osteoarthritis, osteoporosis, muscle weakness, muscle wasting, birth defects, periodontal disease, and more.

In my San Francisco Chronicle column on this topic a year or so ago, I pointed out that “vitamin” D is not really a vitamin.  It is a hormone. This means that vitamin D supplements are a form of hormone replacement therapy—not necessarily a good idea.

Are vitamin D supplements needed?  Not if you expose your skin to sunlight for a few minutes a day, even in winter.

Page 1 of 212