Is Dairy Really Bad for You After All?

In my 28-part series (28? Oh, yeah. Really. 28.) on the NIH state-of-the-science conference on Lactose Intolerance, I summarized presentation after presentation that said that Americans needed calcium in their diets to prevent a wide variety of health and bone issues, that they weren't getting this calcium from their current diets, and that they should therefore have more dairy products to get the needed calcium.

It's only fair to say that other distinguished scientists disagree not only with the conclusion, but with the premise. Calcium does not help with these disorders and dairy is not necessary.

Google News threw up - a bad choice of words, sorry - a link to an article that covered this. That link has vanished as mysteriously as it appeared, but I tracked down the original. It appeared in January on Mark Hyman's Ultrawellness site titled Dairy: 6 Reasons You Should Avoid It at all Costs.

He cites the work of Walter C. Willett of the Harvard School of Public Health is listing those six reasons.

1. Milk doesn't reduce fractures. Contrary to popular belief, eating dairy products has never been shown to reduce fracture risk. In fact, according to the Nurses' Health Study dairy may increase risk of fractures by 50 percent!

2. Less dairy, better bones. Countries with lowest rates of dairy and calcium consumption (like those in Africa and Asia) have the lowest rates of osteoporosis.

3. Calcium isn't as bone-protective as we thought. Studies of calcium supplementation have shown no benefit in reducing fracture risk. vitamin D appears to be much more important than calcium in preventing fractures.

4. Calcium may raise cancer risk. Research shows that higher intakes of both calcium and dairy products may increase a man's risk of prostate cancer by 30 to 50 percent. Plus, dairy consumption increases the body's level of insulin-like growth factor-1 (IGF-1) -- a known cancer promoter.

5. Calcium has benefits that dairy doesn't. Calcium supplements, but not dairy products, may reduce the risk of colon cancer.

6. Not everyone can stomach dairy. About 75 percent of the world's population is genetically unable to properly digest milk and other dairy products -- a problem called lactose intolerance.

Hyman's name rang a bell so I searched back through my posts to find Detox Your Brain, Not Your Diet. Oh, him. Detoxification is serious quackery. He's also one of those who think that diet is the way to treat autism and his thinking on it is just as bad as his opinions on detox, as this post from ScienceBlogs should make abundantly clear. Hyman uses cites and references as magicians do hand gestures, purely as distraction. If you go to the Ultrawellness site or read any of Hyman's many books, be sure to detoxify your brain afterward.

Does that mean the Willett therefore is also a quack? Not at all. But Willett is more interesting than a simplistic anti-dairy crusader. I'll take that up tomorrow.

Report From the LI Conference, part 26

We're back to another round of lactose intolerance influences people to not have dairy which lowers their calcium intake which has long term effects. The difference here is that Dr. Johnson looked at people's feelings as well as their behaviors.

Behavioral Factors Related to Lactose Intolerance and Bone Consequences
Susan L. Johnson, Ph.D.
Associate Professor
Department of Pediatrics
Section of Nutrition
University of Colorado Denver
Anschutz Medical Center

Most Important Problems Encountered With Having Lactose Intolerance

1 Not able to eat certain foods that you like

2 Worry about embarrassment at social events because of lactose intolerance

3 Limit your physical activity because of lactose intolerance

4 Concern about not getting enough calcium

5 Concern about developing osteoporosis or other bone diseases

6 Limit activities that take you away from available restrooms

The perceived inability to eat certain foods goes directly to milk drinking. Some people avoid all dairy products because of LI. But realistically, people don't stop eating their favorite foods like cheese, especially on pizza, and ice cream even if they are LI. That's probably why lactose-free ice cream never breaks through in the market.

One thing that's not known and would be helpful is whether adult perceptions of foods that "can't" be eaten because of LI affects the views of their children. Some children, especially Hispanic girls, were more likely than others to think of themselves as LI and so avoid dairy. If milk can be added to breakfasts, however, it's more likely to be drunk.

Report from the LI Conference, part 16

You want embarrassing?

Say you have a major federal agency, one that has responsibilities for a major, crucial, fraction of the nation's wellbeing. Call it, say, the National Institutes of Health. Make them responsible for the program of a major scientific get-together, say the state-of-the-science conference on Lactose Intolerance. And give that agency the very simple, basic responsibility of making the individual segments of that conference program accessible on the Internet, say, by posting links to each presentation and abstract. You do that, as everyone who has any knowledge of the Internet knows, by taking the URL and adding a # plus the name of an internal link.

So the URL for a link to, say, Evidence-based Practice Center Presentation II:
The Bone Health Outcomes of Dairy-Exclusion Diets by Timothy J. Wilt would read something like this:

http:// consensus.nih.gov/2010/lactoseabstracts.htm #Wilt

Simple enough.

Unless, that is, said Timothy J. Wilt, M.D., M.P.H. is the author of two different presentations. In which case, a URL that reads:

http:// consensus.nih.gov/2010/lactoseabstracts.htm #Wilt

takes you to the first of the two. And never the second. So I can't give you a direct link to the abstract of Evidence-based Practice Center Presentation II:
The Bone Health Outcomes of Dairy-Exclusion Diets because the boneheads at the NIH didn't think to make the link read #Wilt2.

Programming, even HTML-markup, is all details. Mistakes and typos are all too easy to make. But somebody has to click on all the links to make sure they work!

Anyway, for all the info about Dr. Wilt and his co-authors, see the entry I posted about part I of their multi-part presentation.

This particular presentation looked again at actual consumption of nutrients among those who had dairy and those who didn't. What happens with those who don't eat or drink dairy? They don't get enough calcium.

Vegan children consumed only 47% of the RDA for calcium. Vegan women got even less, a mere 30%.

The numbers were extremely similar for LI children (45%) and LI women (37%). LI, lactose intolerance, is being defined here as anyone who claimed symptoms from dairy. Those who tested as having a lactase deficiency, technically a somewhat different group, had a somewhat but not terribly different pattern, 44% for children, 50% for women. (Why no results for men? Apparently none of the 52 studies they summarized looked specifically at males apart from other groups.)

Does this lack of calcium make any real different for bones? The evidence there was thoroughly mixed. Some studies found no differences at all, but many did show increases for bone problems of all sorts for people who avoided dairy.

Report from the LI Conference, part 15

Scientists are nothing is not methodical. After examining the consequences of dairy avoidance in children, you couldn't have found a sports book in all Las Vegas that would be willing to take money against what the next panel would be.

Consequences of Excluding Dairy or of Avoiding Milk in Adults
Robert P. Heaney, M.D., FACP, FACN
John A. Creighton University Professor
Osteoporosis Research Center
Professor of Medicine
School of Medicine
Creighton University

To no one's surprise, Dr. Heaney found that adults who think they have lactose intolerance tend to avoid dairy. And in fact, studies have found anywhere from 33% to 80% lower calcium intake in lactose intolerant populations.

Part of his talk did differ from expectations. In what should also be to no one's surprise, taking a properly close look at the nuances give a picture of reality at odds with conventional wisdom.

But it is an oversimplification to focus exclusively on single nutrients, even calcium. Nutrients are not drugs, and they do not act in a vacuum. Rather, like the instruments in a symphony orchestra, they produce their effects in concert with one another. A striking example of this mutual dependence is seen in the interaction of calcium and protein in the diet. Until recently, high protein intakes were considered to be potentially harmful for bone because of their effect on urinary calcium excretion. Increased calciuria was clearly demonstrated for protein and for pure amino acids, whether taken orally or intravenously. However, when protein was fed as a food, strangely there was no effect on calcium balance. More recently, it has become clear that calcium and protein, rather than antagonists, are actually synergistic in their skeletal effects. In postmenopausal women with low protein intakes, increasing calcium intake can slow bone loss, but not much more. By contrast, with high protein intakes, added calcium leads to actual bone gain. This is an important consideration in our context because individuals with low dairy intakes are missing not only the calcium but also a rich source of dietary protein, which is as necessary for bone rebuilding as is the calcium that is the more obvious component of bony material.

In brief, dairy supplies a broad spectrum of nutrients that work together better than gaining them individually or from foods less gifted. Even calcium-fortified orange juice isn't anywhere as good a source as dairy.

And here's a tidbit that will infuriate those who cherry-pick the medical journals for anti-milk reports.

While the focus of this session is predominantly on skeletal effects, it should be stressed that inadequate dairy intake has multiple other consequences as well, including increased risk of metabolic syndrome, hypertension, preeclampsia, obesity, and certain forms of cancer, particularly colon cancer. Thus milk avoidance is, for most adults, a risky behavior.

Reality is a harsh mistress.

Report from the LI Conference, part 14

For the next three posts, we'll be in Section 2 of NIH state-of-the-state presentations on Lactose Intolerance.

What are the health outcomes of dairy exclusion diets?

Consequences of Excluding Dairy, Milk Avoiders, Calcium Requirements in Children
Connie M. Weaver, Ph.D.
Distinct Professor and Head
College of Consumer and Family Sciences
Department of Foods and Nutrition
Purdue University

Although it is perfectly true that a totally adequate intake of nutrients can be achieved without consuming any dairy products, the reality is that Americans as a whole don't follow anything like that diet. They don't come close to getting sufficient nutrients even with dairy. The numbers are scary.

The role of milk products in meeting three nutrients for various age groups is illustrated in Table 1.

Most food guidance patterns recommend 3 cups of low-fat dairy products daily. The table contrasts the proportion of individuals meeting the dairy recommendations with those receiving less than one serving of dairy products as assessed from data from the 1999–2004 National Health and Nutrition Examination Survey (NHANES). The best and most economical source of the limiting nutrients is dairy. Supplements typically do not fill the gap of all these nutrients for those who do not consume recommended intakes of dairy products. Using NHANES 2001–2002 data, Gao et al. determined that it is impossible to meet calcium recommendations while meeting other nutrient recommendations with a dairy-free diet within the current U.S. dietary pattern. Using the 1999–2004 NHANES data, Nicklas et al. determined that < 3% of the U.S. population met potassium recommendations and 55% did not even meet their Estimated Average Requirements for magnesium.

Bone mass growth comes during adolescence, with 95% of adult peak occurring by age 16. Getting proper nutrients in childhood in critical. Dairy drinkers have a real advantage in driving those numbers up to and past the critical requirements. Here's a table of what the bone-related nutrient requirements are for those under 18.

Report from the LI Conference, part 4

Up next was another talk on the basics.

Nutritive Value of Milk and Alternative Sources
Nancy F. Krebs, M.D., M.S.
Professor of Pediatrics and Head of Section of Nutrition
Department of Pediatrics
Health Sciences Center
University of Colorado at Denver

We hear all the time from dairy advocates that dairy needs to be in the food pyramid and be recommended as a major food group because people just won't, at least don't, get their calcium from other sources, even though it's technically possible to.

I knew that, but the the numbers still managed to startle me. "Dairy products provide approximately 70% of calcium in the U.S. food supply." Vegetables are next, at a tiny 8% of the total. Replacing 70% of a critical nutrient is an almost impossible task in less than a generation. Maybe more. That 70% figure has gone down some but it's taken 45 years to do so, and that's with the growth in calcium-fortified foods.

If you do want to avoid milk, the calcium in calcium-fortified orange juice is well absorbed. So is the calcium in calcium-processed tofu and vegetables like kale. The calcium in spinach is not well absorbed, because it contains oxalates that interfere. Fortunately, oxalates are not a common problem in green leafy vegetables, and the ones that do have a high oxalic acid content include chard and beet greens, not huge contributors to the diet.

But if we tried we could just swap out these alternative sources for dairy, right? Sorry, we just don't know. No good studies of whether the functional outcomes of alternative calcium sources are equivalent to dairy have been done.

Lactose-Free Milk and Lots of It

I mention frequently that I learned I was lactose intolerant back in 1978, long before dairy products made without lactose could be found in any supermarket. That's not to impress you with my age or launch into incoherent screeds about how easy you kids have it today. It's more like sheer astonishment at the changes.

Like this week's shopping trip to a local supermarket. The "dairy" case long ago stopped being merely dairy. Or a case. Today it's a bank of vertical refrigerators, six shelves high. Juices of every possible fruit take up three banks at one end, eggs are at the other. In between are milks. Lots of milk, this being a gigantic store, the flagship of the Wegmans chain and the busiest supermarket I know.

And one whole case, top to bottom, was lactose-free milk. Six full shelves of it. No, seven. The next case over had an additional shelf full. Four separate brands of lactose-free milk were represented there, Lactaid, Real Goodness, Hood, and the Wegmans store brand.

When people ask me why they can't find more varieties of lactose-free dairy items I have to tell them that they simply don't sell. Nothing does. Except lactose-free milk. And that seems to be doing fine. Four brands! I remember the first appearance of a lactose-free milk in a supermarket and the first time I saw two brands competing. They might have taken up a shelf between them. They have been times since when I've seriously wondered if the whole market was going to collapse for lack of buyers.

No longer. Apparently we're in good shape for the foreseeable future.

Now you need to start clamoring for lactose-free ice cream. And then start buying it. Wouldn't it be nice to have even one whole shelf in the frozen section for ourselves?