Did the Dairy Council set the RDA for calcium?

Q. The RDA for calcium seems impossible to achieve unless someone eats dairy (or takes supplements), but considering that dairy has been part of the human diet for only a short period of time (and most people are lactose intolerant), how can our requirements really be that high? Is there scientific evidence that we need that much calcium or has the Dairy Council had a hand in the government's guidelines?

A. You mean, was there a conspiracy to get Americans to consume more dairy products by setting the recommendations for calcium intake higher than necessary? I wouldn't go that far (although I'm sure some would!).

The RDA for calcium reflects the realities of the typical Western diet

The RDA for calcium represents the amount that will meet the needs of most (97%) healthy individuals. They're taking into account not only the amount needed to prevent acute calcium deficiency but also to prevent long-term consequences like osteoporosis.

This is based on scientific research, of course. But most of that research is done on people who eat a typical Western diet--which is relatively high in both protein and sodium. Coffee and soft drinks (containing caffeine and phosphates) are frequently consumed.  All of these things can increase the body's calcium requirements.

The RDA for calcium reflects how much calcium it takes for someone with a typical Western diet to maintain adequate calcium stores.  Those on a lower protein or lower sodium diet might require less.

Non-dairy sources of calcium

Not only are dairy products some of the richest sources of dietary calcium, but the calcium in dairy is well absorbed by the body. But if you're not into dairy, canned salmon and sardines are great non-dairy sources. Tiny bones in the fish--so soft that they're simply consumed with the flesh--are what makes these fish good calcium sources.  Kale and collard greens are also good sources. A cup of collards has as much calcium as a cup of milk.

Seven out of ten kids have low vitamin D levels

A new report reveals that 70 million American kids (ranging in age from toddlers to teens) are at increased risk of heart disease, diabetes, and bone problems due to deficient or insufficient levels of vitamin D.  Low vitamin D levels are about 6 times more common in young black Americans because darker skin produces less vitamin D when exposed to sunlight. See also this story in the Washington Post.)

This storm has been gathering for quite some time.  Vitamin D levels in adults are also low and vitamin D deficiency is being linked to an increasing number of serious, chronic conditions and auto-immune diseases. (See also my post "Vitamin D. Now I'm a believer").

Everyone seems to agree on what's causing the problem. We spend less time outdoors, we've been drilled by dermatologists (and cosmetic companies) on the use of sunscreen to protect our skin against skin cancer and premature aging. We (and our kids) get a lot less vitamin D from our diet, chiefly because we drink less milk and more soda than we used to.

(Milk does not contain vitamin D naturally, of course. It's fortified with vitamin D. Fish are the best natural sources of vitamin D.)

It's harder to agree on the solution.  Some argue that high dose vitamin D supplements are the answer. It's a logical leap, but it's still a leap. While we have evidence linking low vitamin D levels to many diseases, there's less evidence to prove that taking vitamin D supplements reduces those risks.  (Correlation does not equal causation.)

It also takes a heck of a lot of vitamin D supplementation to correct a vitamin D deficiency. While the current RDA for vitamin D is 400IU, it can take 10,000 to 50,000IU a day to replenish depleted vitamin D stores in the body. High doses of vitamin D have been found to be safe and well-tolerated. Nonetheless, many experts are wary of this kind of super-high-dose supplementation without medical oversight.

Exposing the unprotected skin to sunlight is a much more efficient way to raise vitamin D levels in the body, but it proves very difficult to make recommendations about how much sunlight a given person needs. It depends on how much skin is exposed, your latitude, your altitude, the time of day, the time of year, atmospheric conditions, and your skin color. (Yikes!).  Plus, you have to weigh the benefits of vitamin D production against the risk of skin cancer and/or sun damage.

Here, for example, are two very different points of view:

UV Advantage,org

SunProtection.net

For what it's worth, here's how I'm balancing the two, pending further findings. 

1. Because my face, neck, and chest have received an awful lot of sun over the years, I always apply sunscreen there to prevent further damage.

2. In the summer, If I'm going to be outside for any length of time between 10AM or 4PM in the summer, I put sunscreen on all exposed skin. Before and after those hours or during the winter, I don't put sunscreen on except if I'm going to be out for a long time.

3. I keep track of and have my doctor check any suspcious moles.

4. I take 1,000IU of vitamin D every day.

If you have children, you might want to ask your pediatrician about it at your next appointment. I'd probably ask whether he/she thinks it would be worthwhile to test your child's vitamin D levels and about guidelines for appropriate sun exposure and/or supplementation.

Updated recommendations for calcium and D

Move over, calcium. Vitamin D now seems to be the premiere nutrient in the fight against osteoporosis. It's been the subject of intense research lately and there's a growing consensus in the scientific community that we need to increase the recommended daily intake for this nutrient. At the same time,  mega-dose calcium supplementation seems to be falling from favor.

In response to the latest research findings, the National Osteoporosis Foundation recently updated their recommendations for these two nutrients. According to the new NOF recommendations, adults under age 50 need 1,000 mg of calcium daily, and adults age 50 and over need 1,200 mg of calcium daily.

Don't forget about food as a source of nutrients!

Note that the NOF recommendatations represent the amount that you should get from dietary sources and supplements combined!  For years, women (especially) have been so brow-beaten (by their doctors, by the media, by manufacturers of calcium supplements) about not getting enough calcium that many now take 1500 mg or more a day in supplement form. 

But the average adult already gets around 600-750mg of calcium from her diet.  Another 1500mg in supplement form is clearly overkill. There's no evidence that getting more than the recommended intake does much good--and many worry that excessive calcium may even be detrimental. At the very least, it can be constipating!

You can use our diet tracking tools to see how much calcium your diet provides. Or, use the following rule of thumb to estimate. The average American diet provides about 250mg of calcium a day not counting dairy products.  Each serving of dairy adds another 200mg or so. I suggest that you take only enough supplemental calcium to make up the difference between your diet and the recommendations.

Just to up the ante a notch further, why not make it a goal (especially for your kids) to get at least 75% of your daily requirement from foods? Use our Nutrient Search Tool to find foods high in calcium.

Vitamin D is another story.

For vitamin D, the NOF recommends that adults under age 50 get 400-800 IU daily, and adults age 50 and older get 800 – 1,000 IU.  But average daily intake from foods is a fraction of that. Fortified dairy products are the primary source of vitamin D in the American diet. It is also found in egg yolks, saltwater fish, and liver--and, of course, produced in the skin when you are exposed to direct sunlight (without sunscreen). 

If you read this blog, you know I'm a BIG proponent of getting nutrients from foods rather than supplements but vitamin D is one that is pretty tough to get from foods alone. I personally take 1,000 IU a day as a supplement, especially in the winter when I am not getting much sunlight on my skin.

Dairy vs. calcium supplements for bone health

You've heard plenty about this already: Most Americans don't get anywhere close the recommended amount of calcium, especially after early childhood.  And as sweetened beverages like sodas, bottled tea, juice and sports drinks edge out milk as our beverages of choice, the gap widens.

For parents, middle-aged women, and others  with "calcium guilt," there are a host of calcium-fortified products that seem as if they might be part of the solution. You can get a dose of added calcium with your orange juice, another by choosing one of the new calcium-fortified cereals, breads, or pastas. Or, pop a couple of pills and you're good to go.

Not so fast, say researchers from Purdue University.  They fed two groups of rats diets containing the same amount of calcium. But one group got their calcium from dairy products and the other in the form of calcium carbonate supplements. The study was funded (but not conducted by) the National Dairy Council, who must have been thrilled to learn that the milk-fed rats ended up with stronger bones than the rats who took calcium supplements.

An aside on industry-funded research: Just because the results are agreeable to the funding agency doesn't necessarily mean that the study was flawed. Although its not a perfect system, there are independent review boards that approve study designs for objectivity. And, to be fair, industry spends lots of money on studies that DON'T deliver the results they hoped for. Nonetheless, it's important know who funds research, which is why I note it here.

In any case, this study seems to reinforce something that we've talked about many times in the past: nutrients seem to be safer and more beneficial when they are consumed as they naturally occur--in foods rather than as supplements.  And this is not the first study to note that the calcium in dairy products is quite well-absorbed.

For my vegan friends and others who eschew dairy products: This does not mean that those who don't consume dairy products are doomed to diseases of calcium deficiency.  Vegetables can provide plenty of calcium, although it is not as well-absorbed as the sources in dairy. However, those who do not eat meat may also NEED less calcium to maintain healthy bones because they tend to consume less protein. (Higher protein diets increase calcium needs.)

Ask Monica: Is dairy a "bad" source of calcium?

Q. I have recently been diagnosed with borderline osteoporosis. My OB/GYN stressed the importance of my finding other protein sources besides dairy. I previously only used skim milk, cottage cheese, yogurt, and cheese for protein sources. The information I read seems split between "dairy is good"/"dairy is bad." Apparently the acid/alkaline levels are a big deal. Please help.

Thanks, Kay

A. Calcium from dairy products is very well-absorbed by the body. On the other hand, some fear that protein foods (including dairy products) are acidifying and cause the body to use up calcium from bone reserves to maintain a proper pH.  Because dairy products are themselves calcium-rich, I don't think that this is as big a deal as some others do.   When your diet is rich in calcium, protein does not cause bone loss.  (Protein and Bone Health: A Paradox Unraveled)

In any case, there are plenty of other foods that are rich in calcium, including many vegetables.  You can see a list of foods high in calcium using the nutrient search tool. One note: spinach, which is high in calcium, also contains oxalates, which can impair calcium absorption. But other high calcium greens like kale, broccoli, and grape leaves do not contain oxalates and are great sources of calcium.  If you are concerned about acid/alkaline balance of your diet, eating a lot of vegetables is the easiest way to keep your diet from being too acidic.

There are also lots of ways to get protein besides dairy products. You don't mention whether you are a vegetarian or not but fish might be an excellent addition to your diet--for several reasons.  Canned salmon or sardines are good sources of protein and good sources of calcium as well!  As a bonus, both are rich in omega-3 fats, which can reduce inflammation.  (Did you know inflammation has been linked to an increased risk of osteoporosis?)

For more surprising facts, check out this week's episode of the Nutrition Diva podcast, which is all about calcium, diet and bone health:

Vitamin D relieves nerve pain in diabetics

A recent study published in the Archives of Internal Medicine found that vitamin D supplementation cut nerve pain from diabetic neuropathy almost in half, prompting researchers to suggest that vitamin D could be used as an effective pain killer for this condition.   

Vitamin D is known to aid in nerve growth and all of the subjects in the study were found to have low levels of vitamin D in their blood.  The study used a daily dose of 2000 IU of vitamin D3 (about 5 times the recommended daily value), an amount that, according to the study authors, is unlikely to cause harmful effects and might even have beneficial effects on bone health.

If you suffer from nerve pain, tingling, or numbness due to complications of diabetes, you might want to ask your doctor about this study and whether vitamin D supplementation would be appropriate for you.

An anti-inflammatory diet can help prevent osteoporosis

A newly published study found that people with signs of systemic inflammation (as measured by blood markers such as C-reactive protein and IL-6) lost more bone mineral density over three years than those with lower levels of these markers.  Translation: Chronic inflammation may increase your risk of osteoporosis.

This sort of systemic inflammation, which is often completely without symptoms, is quite common and increases your risk for all kinds of other health problems as well, including heart disease, Alzheimer's, diabetes, and depression. Inflammation can be driven driven by stress, smoking, being overweight, and diet choices. As a result, an anti-inflammatory diet has become a popular prescription for all that ails us.

The IF (Inflammation Factor) Ratings can be a useful tool in identifying which foods tend to fuel inflammation and which foods tend to quell it.  Foods with positive IF Ratings are considered anti-inflammatory and those with negative Ratings are considered inflammatory.

However, it's not necessary to avoid all negatively-rated foods in order to have a healthy diet. The idea here is simply to balance your choices so that the combined IF Rating over the course of an entire day is in the positive range.

For more on the IF Ratings see our Inflammation Help page as well as several FAQs that I answered in this recent blog post.

Phosphorus: a double-edged sword

We're halfway through Osteoporosis Awareness and Prevention Month and it seems like a good time to take on the complicated issue of phosphorus and bone health.

You've probably seen warnings about soft drinks being bad for your bones. The phosphates used to make soda are a rich source of phosphorus, and excessive intake of this mineral can leach calcium from your bones.

What you rarely see mentioned, however, is that phosphorus deficiency can also contribute to the development of osteoporosis. Most people get the recommended amount of phosphorus from their diets. Yet phosphorus deficiency is becoming more common, particularly among older people. The chief cause? Overly aggressive calcium supplementation!

Calcium and phosphorus are the two main components of bone tissue. It's important to get sufficient amounts of both nutrients for good bone health. But, the ratio of these nutrients is also quite important. If your diet is high in phosphorus and low in calcium, your body will indeed pull calcium from the bone reserves.  But it works the other way as well. Excessive amounts of calcium will decrease your ability to absorb phosphorus, which in turn weakens bone. 

So, say you've taken Osteporosis Awareness Month to heart. You've cut out sodas. You're careful to get three or four servings of dairy every day. Plus, you take 2,000 mg of calcium a day as a supplement.  That's well over the recommended amount of calcium, of course, but perhaps you figure that you need to make up for inadequate calcium intake during your misspent, cola-swilling youth. Better safe than sorry, right?  Maybe not.

Some guidelines:

1. Be sure that you are consistently getting  the recommended amount of calcium (1,000 to 1,500mg from diet and supplements.)

2. Also make sure your diet contains the recommended amount of phosphorus (700mg for adults), especially if you are over 60. This is not hard to do; phosphorus is found a wide variety of foods.

3. But keep in mind that a diet that is very high in either calcium or phosphorus will increase your requirement for the other. 

4. If you take calcium supplements, consider using a form of calcium that contains phosphorus, such as tricalcium phosphate.

Not sure how much calcium or phosphorus (or other nutrients) your diet provides? You can use our diet tracking tools to find out. (Don't forget to add in any supplements you use.) Tracking your diet may reveal that you are getting way more or way less of certain nutrients than you realize, or that the balance between nutrients like calcium and phosphorus is out of whack.

To identify foods that are high or low in certain nutrients, take advantage of our Nutrient Search Tool, as well.

Osteoporosis Awareness: new guidelines focus on men at risk

Although women are routinely screened for osteoporosis starting at around age 50, physicians typically do not worry about the bone health of their male patients. They should.

One in six men will have osteoporosis by age 65 and the vast majority will go undiagnosed and, therefore, untreated--until their bones are so brittle that they may break during everyday activites. By that time, it's usually too late to get much benefit from bone-preserving therapies that can slow bone loss and prevent injury and disability.  Consider this: men who break a hip are twice as likely to die within one year.

New guidelines released this month by the American College of Physicians call for osteoporosis screening for men, beginning at age 65 or earlier, if men are at increased risk. Things that increase risk include:

• taking anti-androgenic drugs (used to treat prostate cancer)
• low body weight
• physical inactivity
• smoking
• low calcium and vitamin D status

May is Osteoporosis Awareness and Prevention Month: Are you doing enough to protect yourself from osteoporosis?

Vitamin A: all your questions answered

I got three questions about vitamin A this week...must be something in the air!

Q. The Nutrition Facts for carrots shows that they are very high in Vitamin A. I thought that vitamin A was only found in animal products and that vegetable sources like carrots contained beta-carotene, a compound that's converted to vitamin A. Can you explain?

A. The type of Vitamin A found in animal foods is called retinol. it's also sometimes referred to as pre-formed vitamin A.  Plants contain precursors to vitamin A (such as beta-carotene), which are converted to retinol in your liver.  The figure that you see in the Nutrition Facts label represents the vitamin A potential of a food--or how much vitamin A your body can either absorb or make from the precursors in that food.

If you scroll down the analysis page to the detail section, you'll see the various vitamin A compounds listed separately (retinol, beta-carotene, lutein, and so on). There, you'll see that carrots contain no retinol but lots of carotenoids. The carotenoids are converted to retinol activity equivalents (how much vitamin A your body can produce from them) and the total is then converted one more time into IU (international units).

Q. In your recent post about vitamin D, you mention that we should be cautious about our intake of vitamin A exceeding 10,000 IU. What are the issues with that? It seems that I get quite a bit of A in my diet (thanks to your website, I now know this!), and there is so much conflicting information out there, it's hard to know what's what.

A. The most important thing to realize is that the concerns about excessive vitamin A intake apply only to retinol and not to vitamin A precursors like beta-carotene.  To see where the vitamin A in your diet comes from, scroll down to the detail section, where you can see how much is in the form of retinol and how much is from carotenoids.

One major concern is that retinol intake of 5,000IU a day can increase the risk of osteoporosis in  older people.  This is the amount found in many multivitamins.  Excessive intake of preformed vitamin A (retinol) can also cause liver damage.  The recommended upper limit for retinol is 10,000IU or 3,000mcg a day.  Note that this is only about three times the recommended daily intake!

The typical diet is not going to exceed this amount. High-dose vitamin supplements and/or taking lots of cod liver oil are the most common culprits. If you take a mult-vitamin, try to find one that provides some or all of the vitamin A activity in the form of beta-carotene. There is no reason to be concerned about getting too much beta-carotene from foods.

Q. Monica, could you please mention something about Retinyl Palmitate as I've seen it in supplements. Is this a synthetic Vit A that we should avoid?

A.  Most of the vitamin A in your liver is stored as retinyl palmitate, which is a compound made of retinol (which is unstable by itself) and palmitic acid (which stabilizes it).  Synthetic retinyl palmitate is frequently used in vitamin supplements and fortified foods and is identical to the retinyl palmitate your liver makes.  Other than the cautions outlined above, there's no reason to avoid it.