Tag Archive for: fractures

Research Update on Vitamin D

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Vitamin D supplementation always seems to be in the health news; one day it’s beneficial, the next not so much. One of the problems is that many studies are observational studies. They take a large group of subjects, such as the Nurses Health Study, use food frequency questionnaires to assess vitamin D intake, and report on bone health and other outcomes over time. That has serious limitations in my opinion, not least among them the reliance on food frequency questionnaires, which have been proven inaccurate. Do you remember what you had for dinner last week or the week before? Neither do I.

In a recently published study, researchers did a meta-analysis on vitamin D in observational studies, randomized controlled trials (RCT) on vitamin D supplementation alone, and RCT on vitamin D plus calcium supplementation. The outcomes were all fractures and hip fractures, and the subjects were mostly older than 65.

While there were issues in just about every observational and RCT of some sort, the analysis of each type of trial combined was that vitamin D supplementation did not have a significant effect on the rate of fractures. However, when vitamin D supplementation was combined with vitamin D and calcium supplementation, there was a 6% decrease in all fractures and a 16% decrease in hip fractures over an average of six years. The amounts of vitamin D used were 400 to 800 IU and 1000 to 1200 mg of calcium per day.

While there’s more research to go including the completion of some of randomized controlled trials used in the analysis, take vitamin D and calcium together to reduce the risk of hip fractures and other broken bones. Better together seems to be more effective than overdoing it on a single nutrient.

What are you prepared to do today?

        Dr. Chet

Reference: JAMA Network Open. 2019;2(12):e1917789.

Vitamin D: Stay the Course

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Let’s finish this look at the recent paper on vitamin D (1). As you could read in Thursday’s Memo, they included some curious studies in their review. Let’s take a look.

Mixed-Purpose Studies

Have you ever eaten leftovers? Sure. Did you take all the different leftovers—the spaghetti, the fried rice, the mashed potatoes and gravy—mix them together in a stew or smoothie, and eat them? Probably not. And that’s the primary problem with this review paper: too many different types of studies.

There were enough papers using very high doses of vitamin D administered orally to the elderly that could have been combined. There certainly were enough studies to use only 800 or 1,000 IUs that could have been combined.

It is not the statistics; it’s the physiology and biochemistry. There’s going to be a difference in how the body utilizes 100,000 IUs at one time versus 1,000 IU every day for 100 days. That has to be acknowledged as a possibility. That it wasn’t illustrates a typical problem in these types of studies.

The Pharmaceutical Model

The real weakness of the studies that were included in this review was that the vitamin D was used as a treatment for a disease rather than as a nutritional supplement. What gets lost in translation is that in several studies where vitamin D was used to address low vitamin D levels in the elderly with and without fractures, there was actual improvement in bone-mineral density.

It begs the question: why would you give astronomical doses to healthy people? That’s what they did in communities of elderly residents. Their intentions were good (they wanted to try to prevent fractures and falls), but it’s a lousy approach. Would you give someone a one-month dose of a blood pressure medication? You could kill them. If you’re going to use a vitamin that has robust uses in the body, you have to respect it. They considered it a nutrient, but used it as a drug.

The only issue that I could find with the high doses of vitamin D is that for some reason, they were associated with an increase in falls. That seems inexplicable to me, but it was a consistent observation at high doses of vitamin D. The only reason I would consider it suspect was that in most studies included in the review paper, people self-reported falls. Still, it was there.

The Bottom Line

The overall problem with this review of vitamin D is that the authors considered only a single factor; bone building is dependent on a variety of nutritional factors that were never considered. Most of all, the great majority of the studies didn’t consider the role of exercise: fewer than five of the 81 studies gave any mention to exercise. In order for bones to grow and recover, they must be stressed on a regular basis. There’s no way to come to the conclusions the authors did without that data.

While researchers looked at only a single factor involving the musculoskeletal system, the immune and nervous systems can still benefit from vitamin D even if bones don’t benefit as much as some supplements promise. Vitamin D has also been shown to help mental health and depression. Some day nutrition research will be done correctly, but it wasn’t served very well by this paper or the studies that were included. I found no reason to stop taking vitamin D as a supplement. In fact, it’s time to increase your dosage as the days get shorter and your sunlight exposure decreases.

What are you prepared to do today?

Dr. Chet

 

Reference: DOI:https://doi.org/10.1016/S2213-8587(18)30265-1.

 

A Potpourri of Research on Vitamin D

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Scientists try to follow some strict guidelines when they select studies to be included in a meta-analysis. With that in mind, here’s some of what I found in reviewing the studies. Remember, they were looking at fractures, falls, and bone-mineral densities.

  • The length of the studies ranged from as short as eight weeks to as long as seven years. The most popular study length was one year, second was two years.
  • Most of the studies focused on the elderly. Falling and fractures are obvious concerns for that population. But they also included papers on post-parathyroidectomy patients of all ages, renal transplant patients, and young patients that were HIV positive where falling and fractures were not obvious consequences of the age group.
  • For the most part, they selected studies with vitamin D taken via oral supplements. But they also used cod liver oil, with and without vitamin D, as well as intramuscular injections.
  • This one was just simply puzzling. The range of vitamin D administered to the subjects was as low as 400 IU and as high as 600,000 IU in a single dose. Some gave oral vitamin D at 100,000 IUs four times per year, injections of 300,000 IU and 600,000 IU, and one study administered 300,000 IU in a single oral dose.

You don’t have to have any type of scientific degree to see the problem with the apples-and-oranges selection of the studies. Competent scientists may be able to account for differences statistically to do the analysis, but they can’t account for the varying physiological impacts on the subjects.

I’ll finish this up on Saturday.

What are you prepared to do today?

Dr. Chet

 

Reference: DOI:https://doi.org/10.1016/S2213-8587(18)30265-1.

Update: Vitamin D’s Health Effects

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With all the political headlines last week, an important health headline could have been overlooked. A group of scientists published a paper suggesting vitamin D doesn’t prevent fractures and falls or help increase bone-mineral density, and they recommended that it not be used for that purpose. I’m a strong believer that vitamin D is one of the fundamental supplements we should take, so I took a close look at this paper.

Typically I call this a Research Update, but I’m intentionally not calling it that this time because there’s no new research in this paper. This was a research review paper that included a re-analysis of prior research, some 81 studies. That’s a meta-analysis, a statistical technique that has risen in popularity in the past 10 years. In fact, it really only included research published since 2014, the last time some of these authors did the exact same analysis. Based on the prior research of the statistician involved who was the lead author, I have to believe the math is correct.

The problem is in the selection of the studies. I did something I don’t always do. I examined almost all of the abstracts of the 81 papers that were used in the meta-analysis. It was tedious to say the least. To be blunt, I don’t understand how some of the papers were selected. On Thursday, I’ll give you the run down on the research review part of the paper.

What are you prepared to do today?

Dr. Chet

 

Reference: DOI:https://doi.org/10.1016/S2213-8587(18)30265-1.

 

Why Nutrition Is a Process

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A celebrity doctor who specializes in cancer treatment said something that caught my attention, and it goes to this question: why are some people cured by specific treatments while others don’t respond at all? In his opinion, it’s because the cancer creates a new system in the body that competes with the other systems.

The new system may be different in each body once the cancer is established, which could mean that everyone really requires an individual approach. A systems approach would be necessary only if the cancer gets too established; early diagnosis can use treatments that work in most people. Late diagnosis means the cancer has established a system with strengths and weaknesses that are unknown. But the systems approach isn’t limited to cancer.

What’s a Systems Approach?

A systems approach is simply this: we attempt to reach a goal by looking at the interactive nature and interdependence of all the factors in an entity.

Here’s an analogy: you flip the switch for the light in your kitchen, but the light doesn’t go on. What could be wrong? The light won’t work if:

  • Your bulb is burned out
  • Your circuit breaker needs to be reset
  • An electrical outlet somewhere has a tripped GFCI
  • Your switch has gone bad
  • A wire is loose in your light fixture
  • The power is out to your whole house

Turning on a light is easy—my grandson Riley is very good at it and he’s not even three. But if it’s not working, you have to look at each element of the system to find the problem and get the kitchen light back on.

How Vitamin D is Part of Your Bone Health System

While osteoporosis or weight gain doesn’t create a new system like cancer does, there are numerous steps in both processes. On top of that, if we’ve been on the path to bone loss or weight gain, there may be changes in normal metabolism that have to be overcome.

Let me explain using vitamin D for bone health. Whether we make vitamin D in our skin, get it from food, or take it in supplement form, it has to be processed by the liver to become the active form to promote bone growth. If there’s a defect in getting the raw vitamin D from food or a supplement into the bloodstream and on to the liver, not enough vitamin D would be made into the active form. Or there may be a defect in the processing of the raw vitamin D once it gets to the liver. Or there may a defect in the receptor for the active vitamin D on the target tissue. I could go on and on about where issues could occur, but I hope you get the point. Right now, we have no idea where the issue might be for the use of vitamin D in an individual just as we don’t know where the weak point of a cancer system might be and thus where we should attack.

Do we quit? No. We simply use a systems approach—we look at every step necessary to reach our goal and what we can do at each step. We begin with taking vitamin D for a specific period of time. We then get re-tested, most likely a bone density scan. If there’s growth, great. If there’s not, then we either add more D or add calcium or switch to a different form of calcium. Then retest. If that doesn’t work we can add vitamin C or glucosamine, both critical to the manufacture of connective tissue. There are other factors such as smoking and exercise that also impact bone growth. We systematically add new variables or add more of some that we’re already doing. Might this take a long time? Yes. Would we have to pay attention? Yes. But is it a natural approach to complicated conditions? Again, yes. No matter what the condition, if you’re going to try to deal with it nutritionally, that’s the approach you’ll have to take. You have to find what works for you.

The Bottom Line on Vitamin D

The systems approach goes a long way to explain why some people benefitted from vitamin D and calcium to prevent fractures and others did not. The only fact the meta-analysis study proves is that vitamin D and calcium supplementation don’t work for everyone. The key is to move on to the next approach; it may be different supplements or it may even be a medication. More options must be tried until a solution is found for each individual.

Over time, I’m going to continue to explore this concept of a systems approach to nutrition. I have no idea where it will lead, but it’s worth spending more time thinking and researching it.

What are you prepared to do today?

Dr. Chet

 

Reference: JAMA. 2017;318(24):2466-2482. doi:10.1001/jama.2017.19344.

 

You Actually Have to Take the Supplements

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The authors of the study on calcium and vitamin D supplementation as they relate to fractures were all orthopedic surgeons, as stated in the paper. They had no known training in nutrition. Maybe not statistics either.

When you perform a meta-analysis, each research study included is given a weight in the form of a percentage, which indicates how much it contributed to the outcome. Not all studies should contribute equally; that helps to eliminate the bias of a tremendous benefit in a very small study versus a large study with no benefit. They didn’t seem to read something in three studies that contributed close to 90% of the analysis (2-4): the authors of those papers said that the reduction in fractures did occur, or at least bone was restored, when the subjects took over 80% of the doses of calcium and vitamin D they were supposed to take. The problem: average compliance was around 50%.

What these surgeons could have done was tease out the data on those subjects who were compliant and analyzed that data. What they might have had were results that demonstrated that in order to get a benefit, subjects had to take the supplements regularly. That would have been meaningful. Instead, inexperience or ignorance left us with headlines but little else.

Still, there are some questions that were raised in my mind and I’ll cover them on Saturday. But one thing won’t change: if you’re going to take supplements of any kind, you’ve got to actually take them if you want a benefit.

What are you prepared to do today?

Dr. Chet

 

References:
1. JAMA. 2017;318(24):2466-2482. doi:10.1001/jama.2017.19344.
2. Lancet. 2005;365(9471): 1621-1628.
3. Arch Intern Med. 2006;166(8):869-875.
4. Am J Med. 2006;119(9):777-785.

 

Are Vitamin D and Calcium Still Worth Taking?

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Maybe you recently read a headline that went something like this: “Vitamin D and Calcium Do Not Prevent Fractures.” Many headlines were much worse. Over this past weekend I read the research paper published in JAMA. Is it real? Should you not bother taking your calcium and vitamin D to protect your bones? No—keep taking them. But it does give me an opportunity to talk about some of the issues surrounding these types of papers as well as the complexity of nutrition for our health. That’s our topic this week.

The study was a meta-analysis of studies that examined the relationship between the risk of fractures in elderly populations and supplementation with calcium, vitamin D, and both supplements together. After a rigorous database search, 33 randomized controlled trials were included in the meta-analysis. Some studies lasted several months, and some lasted several years. The amounts of calcium and vitamin D in the supplements varied in every study. After analysis, the researchers determined that neither calcium nor vitamin D nor the combination of both reduced the rate of fractures when compared to placebo. That led to their conclusions.

This was a mess as you probably guessed with differing quantities and lengths of the trials. What bothered me most was that if they really understood nutrition as well as the results of the studies they included, they could have done something special. I’ll cover that on Thursday.

What are you prepared to do today?

Dr. Chet

 

Reference: JAMA. 2017;318(24):2466-2482. doi:10.1001/jama.2017.19344.