Do Calcium Supplements Prevent Bone Fractures? – Part1

Written by Dr. Steve Chaney on . Posted in current health articles, Health Current Events, Supplements and Health, Vitamins and Health

Why The Recent Headlines May Be Misleading

Author: Dr. Stephen Chaney

 

osteoporosisDoes calcium help prevent bone fractures?  Osteoporosis is a debilitating and potentially deadly disease associated with aging. It affects 54 million Americans. It can cause debilitating back pain and bone fractures. 50% of women and 25% of men over 50 will break a bone due to osteoporosis. Hip fractures in the elderly due to osteoporosis are often a death sentence.

For that reason, the RDA for calcium has been set at 1,000 to 1,200 mg/day to reduce the risk of osteoporosis, and calcium supplements are often recommended to reach that target.However, recent headlines are proclaiming that calcium supplements do not actually prevent bone fractures and might increase your risk of a heart attack. Are the RDA recommendations wrong? Should you throw out your calcium supplements?

In this article I will review the article behind the study and help you put it into perspective. After all, you don’t really want to know whether calcium supplementation is beneficial for the average adult. You want to know whether it will be beneficial for you.

Let me start by putting the heart attack myth to rest. I have covered this in detail in a previous “Health Tips From The Professor” article, Calcium Supplements Increase Heart Attack Risk . If you don’t want to go to the trouble of reading my previous article, the short version is that:

  • Most of the studies suggesting an increased risk of heart attacks are flawed.
  • A very large study (74,000 women followed for 24 years) has shown fairly convincingly that calcium supplements do not increase heart attack risk. If anything, they decrease heart attack risk.

Unfortunately, like most other nutrition myths, this one is still being repeated – even after it has been refuted by subsequent studies.

Bone Metabolism and Osteoporosis

bone metabolism osteoporosisBefore you can truly understand osteoporosis and how to prevent it, you need to know a bit about bone metabolism. We tend to think of our bones as solid and unchanging, much like the steel girders in an office building. Nothing could be further from the truth. Our bones are dynamic organs that are in a constant change throughout our lives.

Cells called osteoclasts and osteoblasts constantly break down old bone (a process called resorption) and replace it with new bone (a process called accretion). Without this constant renewal process our bones would quickly become old and brittle (I’ll discuss more about this next week when I talk about the side effects of drugs commonly used to increase bone density).

When we are young the bone building process exceeds bone resorption and our bones grow in size and in density. During most of our adult years, bone resorption and accretion are in balance so our bone density stays constant. However, as we age bone the bone building process (accretion) slows down and we start to lose bone density. Eventually our bones look like Swiss cheese and break very easily. This is called osteoporosis.

We should also think of our bones as calcium reservoirs.  We need calcium in our bloodstream 24 hours a day for our muscles, brain, and nerves to function properly, but we only get calcium in our diet at discrete intervals. Consequently, when we eat our body tries to store as much calcium as possible in our bones. Between meals, we break down bone material so that we can release the calcium into our bloodstream that our muscle, brain & nerves need to function.

If we lead a “bone healthy” lifestyle, all of this works perfectly. We build strong bones during our growing years, maintain healthy bones during our adult years, and only lose bone density slowly as we age – maybe never experiencing osteoporosis. We always accumulate enough calcium in our bones during meals to provide for the rest of our body between meals.

What is a “bone healthy” lifestyle, you might ask. Because calcium is a major component of bone, the medical and nutrition communities have long focused on calcium as a “magic bullet” that can assure bone health. Once the importance of vitamin D was understood, it was added to the equation. For years we have been told that if we just get enough calcium and vitamin D in our diets, we would build strong bones when we were young, maintain bone density most of our adult years, and lose bone density as slowly as possible as we age.It is this paradigm that the current study challenges.

Do Calcium Supplements Prevent Bone Fractures?

prevent bone fracturesLet’s start by looking at the study behind the headlines (Tai et al, British Medical Journal, BMJ/2015; 351:h4183 doi: 10.1136/bmj.h4183). This was a meta-analysis that included 15 studies (1533 participants) looking at dietary sources of calcium and 51 studies (12,257 participants) looking at calcium supplementation in women.

The results of the meta-analysis were thought provoking, but do not exactly support the headlines you have been reading. For example:

The headlines say “Calcium Supplements Do Not Prevent Broken Bones”.

  • This study did not actually look at calcium supplementation and the risk of bone fractures. That was a previous study (Boland et al, BMJ 2015, 351:h4580) by the same authors.
  • This study showed that calcium supplementation increased bone density by 0.7-1.8%, which the authors concluded was sufficient to reduce fracture risk by about 5-10%. That’s a disappointingly small effect, but it is not zero – as the headlines suggested.

The headlines say “It’s better to get your calcium from food than from supplements”.

  • This study showed that it did not matter whether the calcium came from food or from supplements. The increase in bone density was identical.

Garbage-In, Garbage-Out

garbageMeta-analyses such as this one can be very strong, but they can also suffer from the “garbage-in, garbage-out” phenomenon. In short, if most of the studies that went into the meta-analysis were poorly designed, the conclusions of the meta-analysis will be unreliable.

The problem is that many of the individual studies were conducted 10, 20, 30 or 40 years ago when our knowledge of bone metabolism was incomplete.

  • Thirty or 40 years ago it was “state of the art” to just use a calcium supplement. Then we learned that adequate vitamin D was essential for efficient calcium utilization.
  • Most of the studies included in this meta-analysis looked at calcium supplementation without vitamin D. Only 13 of the studies (25%) included vitamin D.
  • Ten or 20 years ago it was “state of the art” to just use a calcium supplement with vitamin D. Then we learned that the blood level of 25-hydroxyvitamin D (the active form of vitamin D in the bloodstream) did not necessarily reflect vitamin D intake from the diet. In today’s world a study in which the 25-hydroxy vitamin D level is not measured should be considered sub-standard.
  • Only 18 (35%) of the studies measured baseline 25-hydroxy vitamin D levels.
  • If dietary calcium intake at baseline is already adequate, it is illogical to expect additional calcium to significantly increase bone density.
  • The baseline calcium intake was <800 mg/day (clearly inadequate) in only 26 (51%) of the studies. Baseline calcium intake was either not determined in the other studies or was already in the adequate range prior to supplementation.
  • In the future, we will probably want to include exercise as a component in the study (more about that next week). None of the studies included exercise as a component

In short, by today’s standards many, if not most, of the studies included in the meta-analysis had an inadequate design.

If I had designed the meta-analysis, I would have been a lot more restrictive in the studies I included.

  • I would have started by including only studies in which the baseline intake of calcium was <800 mg/day. If you want to critically evaluate whether calcium supplementation has a beneficial effect, you need to start with people who have an inadequate dietary intake of calcium. If their diets are already calcium sufficient, supplementation is unlikely to have any benefit.
  • At the very least I would only include studies that used calcium supplements containing 400-800 IU of vitamin D as well. In fact, based on the latest data, I would make sure that the calcium supplement I used also contained adequate levels of magnesium, vitamin K, zinc, copper and manganese. All of those have been shown to be important for bone formation and we cannot assume they are present at sufficient levels in their diet (more about that next week).
  • I would only include studies that measured blood levels of 25-hydroxy vitamin D at baseline and following supplementation with vitamin D so that we knew that the 25-hydroxy vitamin D level was sufficient to support optimal calcium utilization.
  • Finally, I would only include studies that specifically measured the effect of exercise on calcium utilization or included exercise as an integral part of their study.

The number of studies included in the meta-analysis would be much less, but they would all be high quality studies.

Finally, the authors also noted that a number of studies in the supplement group showed significantly greater (2.5 – 5.0%) increase in bone density. They dismissed them as outliers. I would have preferred a closer look at those studies to see if there was anything about the population group or study design that might explain the greater bone density increase in those studies.

Apples and Oranges

apples orangesBecause the authors included a wide variety of clinical studies, they were able to state that “Increases in bone mineral density were similar in trials of calcium monotherapy [calcium by itself] versus co-administered calcium and vitamin D…and in trials where baseline dietary calcium intake was <800 [clearly insufficient] versus >800 [probably sufficient] mg/day.” This could be considered a strength of their meta-analysis, but they are only valid comparisons if other important features of the studies being compared were uniform – i.e. they were comparing apples to apples.

But what if they were comparing apples and oranges?

For example, we know that vitamin D is required for efficient calcium utilization. When the authors compared studies having a baseline calcium intake of <800 mg/day with studies having a baseline calcium intake of >800 mg/day, they did not even check to see whether use of vitamin D was evenly distributed between the two groups. If most of the studies with a baseline calcium intake of <800 mg/day did not include vitamin D with their calcium supplements, the authors would be comparing apples and oranges. The comparison would be invalid.

Similarly, we also know that if calcium intake at baseline is adequate, adding more calcium is unlikely to increase bone density significantly. When the authors compared studies with and without vitamin D, they did not even check to see whether baseline calcium intake was evenly distributed between the two groups. If the participants in most of the studies utilizing supplements providing both calcium and vitamin D were already consuming sufficient calcium at baseline, they would be comparing apples to oranges. Again, the comparison would be invalid.

The authors of the meta-analysis simply did not provide the detail needed to determine whether their comparisons were apples to apples or apples to oranges. Thus, what seemed to be a strength of their study is actually a major weakness.

 

The Bottom Line

 

  • A recent study has reported that the RDA recommendation of 1,000 – 1,200 mg/day of calcium for people over 50 provides only a minimal increase in bone density (0.7-1.8%) over the first year or two. This translates into a very small (5-10%) decrease in risk of bone fractures. It did not matter whether the calcium came from dietary sources or from supplementation. The authors concluded that adding extra calcium to the diet, whether from food or supplements, was not a very efficient way to increase bone density and prevent fractures.
  • This study suffers from some serious flaws. It is a meta-analysis of previous clinical trials looking at the effects of calcium on bone density. Meta-analyses can be very strong studies because they average the effects of many individual studies. However, meta-analyses can also suffer from the “garbage-in, garbage-out” phenomenon. Simply put, the quality of the meta-analysis is only as good as the studies that go into it. In this case the meta-analysis included many clinical studies that were done 10, 20, 30 and even 40 years ago. Based on what we now know about bone metabolism, the design of many of those early studies was clearly inadequate (details are given in the article).

 

These statements have not been evaluated by the Food and Drug Administration. This information is not intended to diagnose, treat, cure or prevent any disease.

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Comments (1)

  • Robert D. Munson

    |

    Thank you for pointing out why the results of poorly run research results should not be considered valid, and the difference between well designed and poorly designed research studies. I appreciate you “Health Tips”!!!!

    Reply

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Latest Article

Omega-3 Benefits: Lower High Blood Pressure

Posted July 16, 2019 by Dr. Steve Chaney

What Does the FDA Say About Omega-3 Benefit Claims?

Author: Dr. Stephen Chaney

 

 

Among omega-3 benefits is lower high blood pressure.  That claim can be made according to the FDA. 

lower high blood pressureHeart Disease is still the number 1 cause of death in this country. And, while deaths from heart disease have been declining in recent years, deaths due to high blood pressure have been increasing.  That is concerning because:

High blood pressure is a killer! It can kill you by causing heart attacks, strokes, congestive heart failure, kidney failure and much more.

High blood pressure is a serial killer. It doesn’t just kill a few people. It kills lots of people. The American Heart Association estimates that high blood pressure directly or indirectly caused 410,000 deaths in 2014. That is almost 1 person every second and represents a 41% increase from 2000. It’s because high blood pressure is not a rare disease.

  • 32% of Americans have high blood pressure, also called hypertension, (defined as a systolic blood pressure of 140 mm Hg or more or a diastolic blood pressure of 90 mm Hg or more).
  • Another 33% of Americans have prehypertension (systolic blood pressure of 120-139 mm Hg or diastolic blood pressure of 80-89 mm Hg).

That’s over 65% of Americans with abnormal blood pressure!

High blood pressure is a silent killer. That’s because it is a very insidious disease that sneaks up on you when you least expect it. Systolic blood pressure increases 0.6 mm Hg/year for most adults over 50. By age 75 or above 76-80% of American adults will have high blood pressure.  Even worse, many people with high blood pressure have no symptoms, so they don’t even know that their blood pressure is elevated. For them the first symptom of high blood pressure is often sudden death.

Blood pressure medications can harm your quality of life. Blood pressure medications save lives. However, like most drugs, blood pressure medications have a plethora of side effects – including weakness, dizziness, fainting, shortness of breath, chest pain, nausea, diarrhea or constipation, heartburn, depression, heart palpitations, and even memory loss. The many side effects associated with blood pressure medications lead to poor compliance, which is probably why only 46% of patients with high blood pressure are adequately controlled.

You do have natural options. By now you are probably wondering whether there are natural approaches for controlling your blood pressure that are both effective and lack side effects. The answer is a resounding YES! I’ll outline a holistic natural approach for keeping your blood pressure under control in a minute but let me start with the FDAs recent approval of what they call “qualified claims” that omega-3s lower blood pressure.

 

What Does the FDA Say About Omega-3 Benefits?

omega-3 benefitsIn my book “Slaying The Supplement Myths” I talk about the “dark side” of the supplement industry. There are far too many companies who try to dupe the public by making outrageous and unsubstantiated claims about their products.

Only the FDA stands between us and those unscrupulous companies, and they take their role very seriously. That is why it is big news whenever the FDA allows companies to make health claims about their products.

Even then, the FDA is very cautious. They allow what they call “qualified” health claims. Basically, that means they are saying there is enough evidence that the health claim is probably true, but not enough evidence to say it is proven.

Of course, if you understand the scientific method, you realize there will always be some studies on both sides of every issue. That is why the only health claims the FDA allows are qualified health claims.

With that background in mind, let’s look at the qualified health claims the FDA allows for omega-3 benefits.

  • Since 2004 the FDA has allowed the qualified claim “Supportive but not conclusive research shows that consumption of EPA and DHA omega-3 fatty acids may reduce the risk of coronary heart disease.”
  • A few weeks ago, they added five qualified health claims about omega-3s and blood pressure. The 5 claims are very similar, so I will only list two below for the sake of brevity.
  • “Consuming EPA and DHA combined may reduce blood pressure and reduce the risk of hypertension, a risk factor for CHD (coronary heart disease).”
  • Consuming EPA and DHA combined may reduce the risk of CHD (coronary heart disease) by lowering blood pressure.
  • Of course, they add the usual wording about the evidence being inconsistent and inconclusive.

 

Omega-3 Benefits?

measure omega-3 benefits levelWe’ve known for some time that omega-3 fatty acids help lower blood pressure, but two recent studies were instrumental in convincing the FDA to allow these qualified health claims. These studies have highlighted just how strong the effect of omega-3s on lowering blood pressure is.

The first study was a meta-analysis of 70 randomized, placebo-controlled clinical trials of long chain omega-3 (EPA + DHA) supplementation and blood pressure (Miller et al, American Journal of Hypertension, 27: 885-896, 2014 ).

This study showed:

  • In the group with normal blood pressure at the beginning of the study EPA + DHA supplementation decreased systolic blood pressure by 1.25 mm Hg.
  • Given that systolic blood pressure rises an average of 0.6 mm Hg/year in adults over 50, the authors estimated that omega-3 supplementation alone would delay the onset of age-related high blood pressure by 2 years.
  • In the group with elevated blood pressure not taking medication at the beginning of the study, EPA + DHA supplementation decreased systolic blood pressure by an impressive 4.51 mm Hg and diastolic blood pressure by 3.05 mm Hg.
  • The authors noted that this decrease in systolic blood pressure could “prevent an individual from requiring medication [with all its side effects] to control their hypertension” or decrease the amount of medication required.

However, the doses of omega-3s used in these studies ranged from 1 to over 4 grams/day (mean dose = 3.8 grams/day). That sparked a second study (Minihane et al, Journal of Nutrition, 146: 516-523, 2016) to see whether lower levels of omega-3s might be equally effective. This study was an 8-week double-blind, placebo-controlled study comparing the effects of 0.7 or 1.8 grams of EPA + DHA per day (versus an 8:2 ratio of palm and soybean oil as a placebo) on blood pressure.

This study showed:

  • In the group with normal blood pressure at the beginning of the study, EPA + DHA supplementation caused no significant decrease in blood pressure. This could be due to the smaller number of subjects or the lower doses of EPA + DHA used in this study.
  • In the group with elevated blood pressure not taking medication at the beginning of the study, EPA + DHA supplementation decreased systolic blood pressure by 5 mm Hg and, the effect was essentially identical at 0.7 grams/day and 1.8 grams/day.
  • The authors concluded “Our data suggest that increased EPA + DHA intakes of only 0.7 grams/day may be an effective strategy for blood pressure control.”

 

A Holistic Approach to Lower High Blood Pressure

holistic approach to lower high blood pressureThe FDA’s allowed claims about omega-3s are good news indeed, but that’s not the only natural approach that lowers blood pressure. You have lots of other arrows in your quiver. For example:

  • The DASH diet (A diet that has lots of fresh fruits and vegetables; includes whole grains, low fat dairy, poultry, fish, beans, nuts and oils; and is low in sugar and red meats) reduces systolic blood pressure by 5-6 mm Hg. [Low fat, low carb and Mediterranean diets also lower blood pressure, but not by as much as the DASH diet].
  • Reducing sodium by about 1,150 mg/day reduces systolic blood pressure by 3-4 mm Hg.
  • Reducing excess weight by 5% reduces systolic blood pressure by 3 points.
  • Doing at least 40 minutes of aerobic exercise 3-4 times/week reduces systolic blood pressure by 2-5 mm Hg.
  • Nitrates, whether derived from fresh fruits and vegetables or from supplements probably also reduce blood pressure, but we don’t yet know by how much.

If you’ve been keeping track, you’ve probably figured out that a holistic lifestyle that included at least 0.7 grams/day of long chain omega-3s (EPA + DHA) plus the other omega-3 benefits in the list above could reduce your systolic blood pressure by a whopping 18-22 mm Hg.  What

That’s significant because, the CDC estimates that reducing high systolic blood pressure by only 12-13 mm Hg could reduce your risk of:

  • Stroke by 37%.
  • Coronary heart disease by 21%.
  • Death from cardiovascular disease by 25%.
  • Death from all causes by 13%.

 

A Word of Caution

While holistic approaches have the potential to keep your blood pressure under control without the side effects of medications, it is important not to blindly rely on holistic approaches alone. There are also genetic and environmental risk factors involved in determining blood pressure. You could be doing everything right and still have high blood pressure. Plus, you need to remember that high blood pressure is a silent killer that often doesn’t have any detectable symptoms prior to that first heart attack or stroke.

My recommendations are:

  • Monitor your blood pressure on a regular basis.
  • If your blood pressure starts to become elevated, consult with your doctor about starting with natural approaches to bring your blood pressure back under control. Doctors are fully aware of the side effects of blood pressure medications, and most doctors are happy to encourage you to try natural approaches first.
  • Continue to monitor blood pressure as directed by your doctor. If natural approaches are insufficient to bring your blood pressure under control, they will prescribe the lowest dose of blood pressure medication possible to get your blood pressure where it needs to be.
  • Don’t stop making holistic lifestyle choices to reduce blood pressure just because you are on medication. The more you do to keep your blood pressure under control with a healthy diet and lifestyle, the less medication your doctor will need to use (That means fewer side effects).

 

The Bottom Line

Heart Disease is still the number 1 cause of death in this country. And, while deaths from heart disease have been declining in recent years, deaths due to high blood pressure have been increasing. That is why anything we can do lower blood pressure naturally is important. What does the FDA say about omega-3s and blood pressure?

  • Since 2004 the FDA has allowed the qualified claim “Supportive but not conclusive research shows that consumption of EPA and DHA omega-3 fatty acids may reduce the risk of coronary heart disease.”
  • A few weeks ago, they added qualified health claims about omega-3s and blood pressure. For example, they now allow the following claims.
  • “Consuming EPA and DHA combined may reduce blood pressure and reduce the risk of hypertension, a risk factor for CHD (coronary heart disease).”
  • Consuming EPA and DHA combined may reduce the risk of CHD (coronary heart disease) by lowering blood pressure.

For more information on the studies that convinced the FDA to allow claims about omega-3s and blood pressure and for a discussion of holistic natural approaches for lowering blood pressure, read the article above.

 

These statements have not been evaluated by the Food and Drug Administration. This information is not intended to diagnose, treat, cure or prevent any disease.

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