Tag Archive for: type 2 diabetes

The FFQ: Still Too Vague

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I spent a long time examining validation and reliability studies on the Food Frequency Questionnaires (FFQ). It was interesting to compare the original validation studies with a new FFQ that was published in early 2024; researchers asked subjects in those studies that began decades ago to participate in this recent validation study.

The Stats

I learned more about a variety of statistics that I don’t typically encounter: coefficient of correlation, and then attenuated and deattenuated coefficient of correlations, and more. The researchers concluded that the “study showed that the FFQ used in prior studies has reasonably high reproducibility and validity in measuring food and food groups intakes among both women and men.” I disagree.

The coefficient of correlation is important (COC) because it gives an indication of the association of the variable with a standard, in this case a 7 Day Dietary Recall. The best COC is 1.0 or -1.0, which means it’s perfectly correlated or not correlated with the standard. A COC greater than 0.8 is considered a strong relationship, but a relationship of 0.6 – 0.79 is considered moderate.

The COC for most categories of food was well below 0.6. How can that in any way be valid? It may be reproduceable, but you’re reproducing the same mistake over and over again.

How Dangerous Is Meat?

High level analytics like this aren’t my area of expertise, but logic dictates that you can’t get precision even with large numbers of subjects. This is especially true when using FFQ data to correlate nutrition with disease. Remember the study on red meat intake and type 2 diabetes? The Hazard Ratio was only 10% per 100-gram serving of red meat. If the meat intake is moderately correlated, how much does any error of intake impact the HR?

Whether researchers are trying to estimate how much of each type of meat a person eats or trying to calculate the heme-iron content of that meat, the FFQ doesn’t have enough precision to be used in determining those values. Remember, the increase in HR was 10% per 100 grams—that’s 3.3 ounces—of unprocessed red meat per day. If a patty were 100 grams, a reasonable size, and you ate six patties every day, that would be 600 grams or over 1.5 pounds of hamburger patties per day. Would that raise the HR to 60% based on that single answer? What about a vegan who gets no heme iron? Would they never get type 2 diabetes? We know that’s not true either.

One more thing: People under-report what they eat. It can be 100 to 200 calories per day, or even up to 500 calories per day. No after-the-fact adjustment of the food intake can make up for that kind of imprecision.

The Bottom Line

What we’re left with is this: There may be a relationship between red meat, and subsequently, heme iron intake, and the risk of type 2 diabetes, but we don’t know how much. That’s about it. We’re going to need much better studies to nail that down before we make a pronouncement. For now, you’re probably safe eating red meat, especially if you keep this in mind: eat better, eat less, and move more.

What are you prepared to do today?

        Dr. Chet

References:
1. Am J Epidemiol. 1985;122(1):51–65.
2. Am J Epidemiol. 2024;193(1):170–179

Ice Cream, the Health Food

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Paula gave me an article to read from The Atlantic written last summer, in which author David Merritt Johns tackled the issue of outlandish results in nutrition-science studies. In this case, the issue was research demonstrating that eating ice cream regularly reduced the risk of developing type 2 diabetes and cardiovascular disease. He interviewed the chairman of acclaimed nutrition research schools and departments. He interviewed the scientists who published the results of the studies—or not, in one case, because they wouldn’t talk about it. No one could explain it, it didn’t fit their model, so the results got buried.

I reviewed the studies in question, including the dissertation of the researchers who wouldn’t talk about the study. Any way you look at it, two servings per week of a half cup of high-fat ice cream reduced the risk of the aforementioned conditions between 12–54%. The researchers didn’t want to talk about it or acknowledge it, but the data is the data.

Five Reasons the Data Should Be Accepted

  • The assumption is that the Dietary Guidelines are correct for everyone. Maybe they aren’t.
  • The studies used a food frequency questionnaire. They’ve been used forever and are still no better than they were when developed, like trying to paint the Mona Lisa with a 6-inch brush. For example, how many servings of carrots did you have in July? Few people could answer with any accuracy, so why are we still depending on these tools?
  • They could have assessed the data differently. Divide the subjects by caloric intake first, then by foods or macronutrients. They used the same approach as I’ve talked about before and statistically added a percentage of calories to see how it would impact the results.
  • Maybe the results are just the results. It really confirmed prior studies. Why would you ignore data just because it doesn’t agree with your view of how things should be?
  • Maybe it’s time to stop parsing the imparsible. When the data tell a different story, quit trying to make it fit your theory of nutrition.

Maybe what they should have done is find out what is found in full-fat ice cream but not in high-fat milk or cream, which do contribute to CVD and T2D. Maybe it’s a microbiome issue. Stop saying it’s an outlier and find out why it appears to work.

The Bottom Line

Nobody asked me, but I think it’s portion control. Two half-cup servings per week is very different from two pints a day. That may be the real reason behind the positive results. If you want to have a couple of half-cup servings of ice cream a week, I don’t think it will harm you and just may help. Just pay attention to the portion size.

What are you prepared to do today?

        Dr. Chet

References:
1. http://nrs.harvard.edu/urn-3:HUL.InstRepos:37925665
2. Arch Intern Med. 2005;165:997-1003
3. JAMA. 2002;287(16):2081-2089. doi:10.1001/jama.287.16.2081
4. https://www.theatlantic.com/magazine/archive/2023/05/ice-cream-bad-for-you-health-study/673487/

Free Men’s Health Webinar

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June is National Men’s Health month. My first thought was to do a series of Memos on the key points of men’s health, but because I can talk faster than I can type (and you may not want to read that much), I decided to do a Men’s Health webinar next Wednesday night, June 26 at 8 p.m. Eastern Time. All you have to do is reply to this email and say something like “I’m in” and I’ll add you to the email list. I’ll send out the login information the day before, with a reminder in Tuesday’s Memo.

While cardiovascular disease and type 2 diabetes can cause the most serious negative outcomes if untreated, men don’t completely understand prostate issues, especially prostate cancer. Most men’s way of dealing with it is to ignore it. I’m a prostate cancer survivor, so I’ll talk about my experience. I’ll provide the top five things you can do to decrease your risk of all the major diseases and conditions that afflict men and what you can do when you’re diagnosed. You’re never too young or too old to take your health into your own hands; there’s always something you can do to be healthier.

Men—you don’t want to miss this webinar. Women are welcome as well.

The live webinar is free next Wednesday, and then I’ll consider having it as a product for a nominal fee. Hearing it live is better, and I know it’s short notice, but so is the warning for a stroke, and none of us need that. Join me next week.

What are you prepared to do today?

        Dr. Chet

What Is Secondary Prevention?

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Secondary prevention encompasses a wide range of health-related conditions. It includes people with risk factors such as high cholesterol and blood pressure, cigarette smoking, elevated HbA1c, atrial fibrillation, and more. It also includes people who may have had a heart attack, stroke, cancer, or were treated and now are trying to prevent a recurrence of another incident. This all falls under the umbrella of secondary prevention.

The problem, as I see it, is that we don’t take the risk factors seriously enough to prevent the occurrence of serious health events. For example, let’s say a person gets a reading of 5.9% in an HbA1c reading. That’s considered pre-diabetic and is definitely on the path to type 2 diabetes. The solution is pretty straightforward: reduce refined carbohydrate intake and total caloric intake if the person has weight to lose. Then start an exercise program and stick to it.

Did you know that within three days of beginning a walking or exercise bike program, your body will begin to utilize insulin better? That’s how quickly your body reduces insulin resistance and starts the path back to a lower HbA1c and thus reducing the risk of type 2 diabetes.

Aging with a vengeance is all about prevention—primary prevention to prevent serious diseases and conditions from occurring in the first place and secondary prevention to deal with them if they do occur. Aging is a risk factor in and of itself but not because of a calendar; it’s the changes that naturally occur as we age. What we do to resist or delay those changes is at least partly in our hands. That’s why I said aging with a vengeance begins in your 30s and maybe even younger.

It all begins with six simple words: Eat less. Eat better. Move more. I’ll continue to comb the research to find strategies to deal with other issues. Next week, I’ll review a research study that reveals the secret to getting results.

What are you prepared to do today?

        Dr. Chet

It’s Official: Prescription Fish Oil

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The U.S. Food and Drug Administration approved the prescription fish oil Vascepa for expanded use on Friday, December 13. The approval for the medication is for the secondary prevention of cardiovascular disease in patients under the following conditions:

  • Triglycerides above 150 mg/dl for everyone with diagnosed CVD and taking a statin medication.
  • Diabetes and two or more additional risk factors for CVD along with taking a statin medication.

The modifiable risk factors for CVD include smoking, obesity, high cholesterol, hypertension, and sedentary living. Remember from our prior series, secondary prevention may help reduce the risk of CVD symptoms developing.

My concerns are the same as they were before. Triglycerides less than 250 mg/dl can be resolved by diet and exercise in most people. Because the mechanism of action is unknown as to how the prescription works, there’s no reason to think that reducing triglycerides by lifestyle change won’t work as well as the prescription; the clinical trial didn’t track this data.

Speaking of lifestyle change, keep in mind the website specials on the Optimal Performance program as we get ready for the New Year. The Basic Meal Plan will teach you how to change your diet to reduce triglyceride levels if your levels are too high.

What are you prepared to do today?

        Dr. Chet

References:
1. http://bit.ly/36EbsYK
2. N Engl J Med 2019;380:11-22. DOI: 10.1056/NEJMoa1812792.

Does Fiber Improve Your Microbiome?

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Now let’s look at the results of increasing dietary fiber for people with diabetes. Researchers recruited over 50 type 2 diabetics (T2D) for a 12-week study. The control group was given standard recommendations for a healthy diabetic diet. All current medications were maintained and both groups received acarbose, a starch blocker. The experimental group was put on a diet of prepared high-fiber foods and a diet higher in vegetables and fruits. Stool samples were collected periodically to assess the impact of the diet on the microbiome.

While the variables were straightforward, the analytic techniques were extraordinarily complex. It’s easy to say you want to examine the microbiome, but that’s not simple to do with thousands of types of microbes to analyze. Several types of bacteria from different species responded to the increase in fiber: bacteria that produced short-chain fatty acids (SCFA). The SCFAs are important because they feed the cells in the gut that do all the work during digestion and absorption.

HbA1c levels decreased faster and in a higher percentage of subjects in the experimental group than the control group. The fiber group also lost more weight and their blood lipids improved more than controls.

This was a small study, limited by the complexity of analyzing the microbiome, but the improvement in T2D simply due to an increase in fiber from foods is important. One more thing: this was a Chinese study, so typical high fiber foods from China were used. Is that important? We’ll find out Saturday.

What are you prepared to do today?

        Dr. Chet

Reference: Science. 2018. 359:1151–1156.

Prescription Fish Oil: Questions Remain

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The REDUCE-IT clinical trial formed the basis for the expanded recommendations for use of Vascepa, the prescription fish-oil medication. This was an expensive trial, involving 11 countries and hundreds of medical centers with 999 physicians who recruited subjects, collected data, and kept track of the subjects for close to five years. With over 8,000 subjects, this was no easy task. As I said in Thursday’s Memo, they examined the primary and secondary prevention when the medication is taken with statins versus a placebo with statins.

While this was a tremendous effort, there are still some concerns, in my opinion.

Study Concerns

A board made up of physicians and the pharmaceutical company’s staff designed the study and helped execute it; the pharmaceutical company paid for the clinical trial, collected and managed the data, analyzed the data, and interpreted the results. Then the statistics were reviewed by an independent statistician. This creates a huge conflict of interest regardless of safeguards that may have been put in place.

When any type of study is supported by companies with vested interests in the outcome, there will always be questions. That has been true for every dietary supplement manufacturer that’s ever funded a study as well as the milk and sugar industry. It’s especially true for this study. I began by talking about a report from the financial sector. Billions of dollars are on the line. That has to be considered by the FDA before final approval is given.

I have a tendency to have faith in science, as skeptical as I may be at times. And that’s where my concerns lie; not in the financial aspect but in the study design and results.

My Concerns

As complicated as this study was, it was incomplete in my opinion. They did not collect any data on the subjects’ diet; a small change in diet could have reduced triglycerides (TG) enough to have a positive impact on secondary outcomes. The median change in TG over five years with the medication was 45 mg/dl, from about 215 down to 170 in the medication group, while it was reduced 13 mg/dl in the placebo group. We don’t know whether a group that focused on dietary changes to reduce TG would have the same reduction in CVD events; that would have been an excellent addition to the study design.

They also didn’t have a group using fish oil from dietary supplements. True, it’s not their responsibility, but we can’t know whether the same benefit might not occur if the dosing of EPA were equal:

  • Almost every study that has used fish oil to examine whether CVD outcomes could be reduced has used fish oil with 1 gram of EPA.
  • If the amount of EPA were the same, a head-to-head comparison between a supplement and medication that each had 4 grams EPA might have found a similar benefit.

The real issue is that we don’t know what makes the fish-oil medication work, just like we don’t know completely how dietary omega-3 fatty acids work. Is it just the reduction in the TG or how the oils work in the body? Are genetics involved? Diet? The microbiome? We have no idea at this time.

The Bottom Line

I’ll keep on eye on the approval process for this fish-oil pharmaceutical and let you know how it will be prescribed in the future. The decrease in TG found in the study can be done with lifestyle changes alone, so is it going to be worth the cost of a pharmaceutical for a slight reduction in CVD events? Remember the difference between medication and placebo was just 4.8%. If you fall in that category, you’ll have to decide for yourself: pharmaceutical fish oil or lifestyle change. In this case, a little work may go a long way.

What are you prepared to do today?

        Dr. Chet

P.S. This will be the last Memo until after Thanksgiving. Paula and I are doing something we haven’t done in 20 years: go on a real vacation, just us, just for fun. No work of any type. Talk to you again December 3.

Reference: N Engl J Med 2019;380:11-22. DOI: 10.1056/NEJMoa1812792.

Primary vs. Secondary Meds

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One of the key questions for the FDA advisory panel to consider was whether the prescription fish oil was a primary preventer of cardiovascular disease or a secondary preventer. What’s the difference? Primary prevention of CVD would impact the disease and stop events before they occurred in the subjects taking the fish-oil medication. Secondary prevention would prevent additional CVD events from happening in those with established CVD.

If you were a type 2 diabetic with an additional risk for CVD such as obesity or being a smoker, taking the prescription fish oil with a statin would prevent a heart attack or stroke from happening; that’s primary prevention. Based on the Reduction of Cardiovascular Events with Icosa-pent Ethyl–Intervention Trial (REDUCE-IT) that didn’t happen, but it did prove to be a secondary preventer of additional cardiac events in those subjects in the study with established disease.

The question is whether the FDA will approve the prescription fish oil as a primary prevention or a secondary prevention pharmaceutical. The advisory panel seemed split on that count. The assumption by some was that there was disease present even though the event had yet to occur. Others said “prove it” by doing an actual clinical trial to examine that question. We’ll find out how the FDA decides later this year. As I mentioned yesterday, the financial implications are huge.

There are still some things to consider with the clinical trial, and I’ll cover that on Saturday.

What are you prepared to do today?

        Dr. Chet

Reference: N Engl J Med 2019;380:11-22. DOI: 10.1056/NEJMoa1812792.

Prescription Fish Oil Update

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“This Fish-Oil Heart Drug Could Be Big, Could Be Huge.” That was the headline in a well-known financial report after a Food and Drug Administration panel unanimously voted in favor of an expanded use for the prescription fish-oil drug. I mentioned this was a possibility when I first talked about Vascepa in October. The FDA is expected to make a final decision by the end of the year.

What is the expanded use? The medication could be prescribed to those who have established heart disease or type 2 diabetes with another CVD risk factor and are already taking statin medications to lower cholesterol. The advisory panel approved the use because research showed that when combined with statins, it could reduce CVD endpoints such as death, heart attacks, and strokes by an additional 4.8% when compared to a placebo over a 4.9 year follow-up period, 17.2% versus 22%.

One more thing. The medication could be prescribed to those with triglycerides as low as 150 mg/dl. That would include millions more potential users in the U.S. and Canada alone. You can see why the headline was in the financial news; the potential profit for investors could be huge. A lot is riding on what the FDA decides. I’ll explain that on Thursday.

What are you prepared to do today?

        Dr. Chet

Reference: Bloomberg Online. Max Nisen. Posted 11-15-2019.

News on Food as Medicine

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As a conventional medical journal and one of the leading medical journals in the world, The Journal of the American Medical Association doesn’t often publish reviews of the impact of food on health. However, a recent edition of the Journal included a summary of three such studies, and that’s the topic for this week.

The first study examined whether mushrooms, which are full of vitamins, minerals, and phytonutrients, decrease the risk of cardiovascular disease (CVD) or type 2 diabetes (T2D). The researchers re-analyzed the data from the Nurses’ Health Study and the Health Professionals Follow-up Study. When they compared more than five servings of mushrooms per day with less than one serving per day, they found no differences in the rate of symptoms or markers associated with CVD or T2D. One interesting note was that if mushrooms were substituted for meat, there was a decreased risk of T2D.

This is one of the first studies to acknowledge the problems with nutrition data in these types of studies. The data on mushrooms were only collected at the beginning of the studies; that doesn’t allow for comparisons over time. Further, the questionnaire didn’t allow for data on a variety of types of mushrooms. The best observation at this point is that we don’t know whether mushrooms or specific types of mushrooms are beneficial for reducing the risk of disease until more research is done.

We do know they’re good for you, so enjoy your mushrooms; sautéed mushrooms are a great addition to many dishes. Here’s another way to enjoy mushrooms: Creamy Mushroom Soup from the Health Info page at drchet.com. Check out the other recipes while you’re there.

We’ll look at another study on Thursday.

What are you prepared to do today?

        Dr. Chet

P.S. Don’t forget to complete the survey on Dr. Chet’s Traveling Health Show. I could be coming to a city near you in 2020! Click the link below to go to the survey.

Survey

Reference: AJCN https://doi.org/10.1093/ajcn/nqz057.