A Potpourri of Research on Vitamin D

/in /by

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

/in /by

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.

 

Absolutely True, Relatively Meaningless

/in /by

In this final Memo about the retraction of several of Dr. Brian Wansink’s publications, there are several important questions that need to be addressed. What do the errors mean? Did Dr. Wansink intend to deceive? Finally, who was making the accusations?
 

Publication Errors and What They Mean

Let’s take a look at the errors I mentioned on Thursday. The first was continually analyzing the data to come up with new hypotheses—that’s not the way research is supposed to be done. In this case, the data were collected via questionnaires after eating at a buffet in a small town restaurant. The purpose was to see if the price of the buffet influenced whether people felt better or worse about their food choices. This wasn’t the best study idea Wansink ever dreamed up; I don’t see the results of this study impacting the obesity epidemic in any way, even if the data were pristine and analyzed precisely without the data churn that came afterward.

The second error pointed out by the post-article reviewers all related to statistical errors. They questioned the data being carried out to the hundredths of a point and stated that there were errors in calculating the means. These were survey results using a Likert scale and should never have been presented other than in whole numbers or at best, to half a point; going to the hundredths just makes no sense. It would have been better to recommend that to the authors than make a big deal about deceptive statistical errors. They also found that the number of subjects continually changed in some analyses: one test said 122 subjects while another said 124. There may have been a degree of ineptitude but again, no attempt to overtly deceive.

Finally, regarding the plagiarism accusation. Wansink did what many authors do: he used prior text taken from his own prior publications and inserted them into articles as appropriate. They should have been cited, but when you re-use what you’ve already written that’s not plagiarism, that’s an oversight or a bone-headed error.
 

Did Dr. Wansink Attempt To Deceive?

I read Dr. Wansink’s blog post that started this whole mess. What he attempted to do was illustrate how new researchers can get published. He had no attempt to deceive anyone. As the blog got more play in the scientific universe, he took some pretty big hits and not in a nice way. He answered every one with respect, including several from one of the accusers.

I came away thinking that Dr. Wansink didn’t understand the ramifications of continually analyzing data with changing hypotheses. In addition, he was not the best statistician and would have been helped tremendously by help from someone who really understood numbers.
 

Who Were His Accusers?

I checked out three of the primary accusers, two of whom had published the article mentioned in Thursday’s Memo (1). They all seem to be fascinated with numbers and scientific purity.

One was a retired physics professor; in his entire academic career, he published two research papers and that was over 30 years ago. He was primarily a physics teacher and retired 19 years ago. My problem isn’t his age, it’s that he hadn’t done much in his own field, let alone Wansink’s.

A second is a PhD candidate in the social sciences. If anyone understands the mess the use of observation and questionnaire testing can present in behavioral research, it would be him. It’s curious that he wouldn’t make that a key element of his paper.

The final accuser was a PhD/MD candidate who was kicked out of his program by his advisors, according to his blog. That gave him plenty of time to do the most in-depth and longest review of Wansink’s papers.

This may sound cruel but what we have is a never-was, a wannabee with very limited experience, and a never-will-be. Not exactly a stellar cast of accusers. They were absolutely correct, but what they showed is relatively meaningless.

What I didn’t see was a review of Wansink’s paper on the never-ending soup bowl (2), maybe because it was based on actual numbers because the amounts of soup were measured. They also failed to mention that another study was replicated and confirmed by another lab (3); it was on how the names of food influences whether children and young adults will eat more vegetables.
 

The Bottom Line

In spite of the publications being retracted, and with that, the forced retirement of Dr. Wansink from his Lab, there’s still value in the research that he’s published. He seemed to be more an idea guy than a bench scientist. Makes sense: his PhD was in marketing so he tried to research people’s attitudes about food. He just didn’t know how to do it very well from a science perspective.

If you want to control your eating, use a smaller plate, plate your food away from the table and don’t add any more, and keep all snacks out of sight. Proof or no proof, those are still good recommendations.

What are you prepared to do today?

Dr. Chet

 

References:
1. BMC Nutrition. doi.org/10.1186/s40795-017-0167-x.
2. Obes Res. 2005 Jan;13(1):93-100.
3. AMA Intern Med. 2017;177(8):1216-1218. doi:10.1001/jamainternmed.2017.1637

 

The Reasons for Retraction

/in /by

Publications related to food habits are important if you’re in the weight loss field; I rely on them to help people achieve their weight loss goals. If the studies were poorly done, that’s unfortunate but behavioral science is an inexact science anyway. But if someone intentionally manipulated the data to get a specific outcome, that’s just not right. Let’s see what several scientists found when they examined Dr. Wansink’s data more closely. What were the problems?

It seems there were three. First, as I mentioned on Tuesday, he had a graduate volunteer continue to examine the data to come up with hypotheses that were significant. That means they organized the data differently and kept running statistical analyses until they came up with something that was statistically significant. As I said, that’s a no-no because of the potential of finding something by chance; you get the best answers to the questions you actually ask, so finding something by accident is not as valid among scientists.

Second, there were errors in the way data were displayed. The reviewers made a very big deal of granularity and how the means displayed weren’t possible. I’ll leave that to the people who specialize in statistics.

Finally, they accused him and his colleagues of plagiarism. If there were an absolute violation of science, that would be it.

But as you might expect, not everything is always as clear as people make it out to be, and I’ll explain that on Saturday. Until then, I would still keep the snacks out of sight and continue using that salad plate instead of a dinner plate in order to eat less.

What are you prepared to do today?

Dr. Chet

 

Reference: BMC Nutrition. doi.org/10.1186/s40795-017-0167-x.

 

Scientific Retractions

/in /by

One of my favorite observational scientists has been Dr. Brian Wansink, former Director of the Food and Brand Lab at Cornell University. I’ve written about his research and used it in presentations several times over the years. One of my favorite tips came from one of his studies: use a salad plate instead of a dinner plate. It cuts down on the food you take at one plate-full by about 25%.

That’s why I was dismayed when I read that several of his papers have been retracted from JAMA and other publications. There are many reasons why a paper can be retracted: problems with data and statistics, questionable research techniques, or unsubstantiated conclusions. Evidently, there was some of all of those accusations, which resulted in the papers being retracted.

Of course I had to check this out. What did he do? How did his papers become suspect to begin with? Who was involved in this process? I’ll answer part of the who right now. It was Wansink himself with a blog post talking about collecting data and then using multiple statistical analyses to get to a hypothesis in a couple of studies. That’s a very big no-no in science.

But due to the nature of his observational research, does it mean all of his work on relationships between habits and food is worthless? We’ll find out this week.

What are you prepared to do today?

Dr. Chet

 

Aspirin and Unintended Consequences

/in /by

We began the week considering a type of shortcut to health called biohacking. The polypill was a biohack to reduce the risk of CVD events, but there’s no research showing whether the polypill will ever prove to be effective. However, the results of the ASPREE trial may give us an idea whether the long-term trials should ever be attempted (1-3). Let’s take a look at the results of the ASPREE trial and the effects of an aspirin a day on healthy older adults.

In the first paper, the researchers evaluated the data to see if those who took the aspirin had less disability (1). In other words, did taking the aspirin convey benefits that reduced the risk of death, disability, or dementia? The data showed no differences between the aspirin and placebo group as it related to those outcomes.

In the second paper, the researchers examined the differences in all-cause mortality (2). What surprised the researchers was a slight increase in death from cancers in the group that took the aspirin; no specific type of cancer seemed to be impacted. Because aspirin has been shown to be beneficial in almost all other studies of cancer and mortality, the researchers said the results should be taken with a degree of caution.

In the final paper, researchers examined whether aspirin reduced the rate of CVD events and stroke (3) and found no difference, but the risk of hemorrhagic stroke was significantly higher in the aspirin group versus the placebo. This was the primary reason the study was terminated after five years.
 

The Problem

There were several problems with the study including the low adherence in both the aspirin and placebo group: if people didn’t take the pills, obviously that impacts the results. But the biggest question I have is a very simple one: who thought it was a good idea to give healthy people a medication every single day? Taking an aspirin for a headache or muscle ache is one thing. Taking it when you don’t need it is another.

The study demonstrated the logical fallacy of the polypill. “People won’t take care of themselves, so let’s put everyone on the medications that can reduce the risk of CVD.” No, let’s not. The results were unintended consequences that put the entire idea of biohacking into question.
 

The Bottom Line

When it comes to health, there are no real shortcuts. Biohacking, while a cute contemporary term, is fool’s gold. Yes, you can use your time and resources more efficiently to improve your health, but there are no shortcuts.

There is also one other obvious conclusion. Healthy people shouldn’t take medication. I take an 81 mg aspirin every day because I have had a stent and my doctor told me to. But I don’t take a statin any more because I changed my diet and lifestyle to keep my cholesterol normal. I control my blood pressure with diet and exercise. I don’t take medications I don’t need.

If you’re willing to do all you can to avoid medications and you still need medication to help you out, do it. But don’t take them to avoid doing the work. There are unintended consequences of taking the easy way out.

What are you prepared to do today?

Dr. Chet

 

References:
1. DOI: 10.1056/NEJMoa1800722.
2. DOI: 10.1056/NEJMoa1803955.
3. DOI: 10.1056/NEJMoa1805819.

 

An Aspirin a Day

/in /by

In Tuesday’s Memo, I talked about biohacking. Specifically, I talked about the idea of having everyone over a certain age take a pill that can impact the risk factors for CVD: high blood pressure, cholesterol, high heart rate, and blood cell stickiness. The idea is that taking that single pill in low doses every day might help reduce CVD events such as strokes and heart attacks.

Researchers in Australia and the U.S. decided to test one component of the polypill: aspirin. The study was called the Aspirin in Reducing Events in the Elderly (ASPREE) trial. They recruited over 19,000 people 70 and older or 65 if they were Black or Hispanic in the U.S. They randomly assigned half the subjects to take 100 mg of enteric-coated aspirin while the other half got a similar looking placebo. The subjects were tracked for an average of 4.7 years. The researchers examined many variables including mortality and the incidence of disease.

The results were published in three separate papers in a recent issue of the New England Journal of Medicine. The study was terminated after five years by the primary funding organization, the National Institute on Aging. The results were not exactly what was hoped. We’ll get into the details on Saturday. If you’d like to read the studies, all are available online at the links in the references.

What are you prepared to do today?

Dr. Chet

 

References:
1. DOI: 10.1056/NEJMoa1800722.
2. DOI: 10.1056/NEJMoa1803955.
3. DOI: 10.1056/NEJMoa1805819.

 

A Look at Biohacking

/in /by

One of the terms that have evolved in the health and fitness field that I really dislike is biohacking. Whether related to fitness, nutrition, or supplementation, the implication is that there are shortcuts to get health benefits. I believe that we can do things that are a more efficient use of time but when it comes to your health, there are no shortcuts. If you want benefits, you have to put in the effort. This week, I’m going to give you an example of a reasonable idea that hasn’t proven to demonstrate the benefits that were expected.

The concept for the polypill was introduced 15 years ago. The purpose was to put together a group of medications that could help reduce the risk of cardiovascular disease (CVD) by giving it to everyone over 55. The polypill was modified over the years to include low doses of aspirin, a statin, beta-blocker, angiotensin-converting enzyme (ACE) inhibitor, diuretic, and folic acid or some combination of these medications. The idea was that putting all the medications together in a single pill would increase adherence, a significant issue when it comes to taking medications. By so doing, it would decrease the risk of CVD disease.

The polypill has not been put into use in the U.S. While there are some positive data from other countries, the clinical trials that have been done are not long enough to demonstrate reduction in mortality and CVD events. But a recent study on one component of that polypill shows that it may not be such a good idea for everyone. I’ll continue on Thursday.

What are you prepared to do today?

Dr. Chet

What We Can Learn from Kipchoge

/in /by

There are a couple of lessons that we can get from Eliud Kipchoge and his approach to setting the world record in the marathon. Let’s take a look at what he did to prepare to be called the best marathoner of all time.

He Knew It Was Possible

When I say he knew it was possible, I don’t mean a theoretical thing. He knew it because he had already run a marathon in 2:00:25, over a minute faster than his current world record. He ran it over a minute faster under controlled conditions on a track. It was not recognized as the world record because he used rotating pacers. That means that every so often, a fresh runner would join him to help him maintain pace. He did have pacers in his world record attempt, but they began the race with him and dropped back when they ran out of gas. He ran the last 11 miles alone and at a faster pace than his pacers helped him keep.

Have you ever lost weight before or lowered your blood sugar? If you have, you know that it’s possible. Maybe your approach wasn’t sustainable or maintainable but if you did it once, you know you can do it. But it takes more than that.

He Got A Little Help

There were coaches, nutritionists, physical therapists, and a whole host of other people involved in getting him prepared. That’s essential. Your physician and other healthcare professionals can help fill that gap for you so you know how to do lose weight or lower your blood pressure responsibly. But the pacers were critical as they were with him on the course. They helped him get through at least half the race until his effort exceeded what they were capable of doing.

There are two ways this helps you in achieving a health goal. First, if you can find someone who is willing to help you on your journey by doing it with you, that can help you tremendously—and it helps them as well. We don’t care about world records; we care about achieving our health goals. You support others as they help you. Sometimes your support group doesn’t stick it out all the way.

That’s when you need to talk or listen to people who’ve already done it. It doesn’t have to be the same goal. It doesn’t even have to be in the same area. But we can all use encouragement in the form of hearing about how others achieved their goals.

The Bottom Line

Kipchoge is the greatest marathoner in the world. We can use what he did as inspiration but more importantly, we can take the lessons in how he did it to achieve our own health goals. Break it down to its simplest component. Rely on our past experience in achieving goals. Get a little help from our friends. Take those lessons and use them and you can change your health.

What are you prepared to do today?

Dr. Chet

Only Three Seconds Faster

/in /by

Eliud Kipchoge shattered the world record for the marathon by one minute, eighteen seconds. But breaking it down, that was about three seconds per mile faster. Sustaining that faster pace for the entire duration was an amazing physical feat but in its essence, it was three seconds per mile.

Let’s carry the logic to weight loss. If you want to lose 52 pounds in a year, that works out to one pound per week. One pound per week is 2.3 ounces per day. While the typical 3,500 calories in a pound of fat isn’t as precise as we’d like it to be, it’s close enough. That works out to be 503 calories per day. We either have to eat 500 fewer calories, burn 500 more calories, or some combination of both. That’s doable.

The key would be to be sustain that for 365 days in a year. Based on the best available research, we seem to do well until about week 10 of any type of diet you might try. That’s when we begin to return to former eating patterns—very slowly, but that’s when the plateaus and weight regain begin.

We could pick any health goal from lowering HbA1c to getting more flexible to reducing blood pressure and use the same approach. We need to know the variable that should be adjusted, from exercise and diet to taking supplements or medications regularly. We can break them all down to this: what do we need to do today?

What can help us sustain the effort once we know what we need to do? More lessons from the world record holder on Saturday.

What are you prepared to do today?

Dr. Chet