Tag Archive for: DHA

Research Update: Omega-3s and Lung Function

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Lung function declines as we age; depending on how we treat our lungs, our habits can determine the rate of decline. Working in toxic situations (or even worse, smoking cigarettes) can accelerate the decline. That’s why a recent study that examined blood levels of omega-3 fatty acids and measures of lung function found that our diet has an impact on lung function. Let’s look at this study.

Increases in Omega-3 Levels Prevent Decline

Of the two studies reported in the paper, I’ll stick to the longitudinal study, although both demonstrated the positive impact of omega-3s on lung function. A couple definitions first.

  • Forced expiratory volume 1 (FEV1) is the amount of air that one can forcefully breathe out in one second. The normal range is 2,500 to 3,250 milliliters.
  • Forced vital capacity (FVC) is the amount breathed out after a normal exhalation. The normal range is 3,700 ml to 4,800 ml.

One more thing: in this study, the mean rate of lung function decline was 36.8 mL per year for FEV1 and 35.8 mL per year for FVC.

Researchers examined a pooled group of studies that were part of the National Heart, Lung, and Blood Institute Pooled Cohorts Study. Studies were chosen because of the repeated measurements of both lung function and plasma phospholipid omega-3 fatty acids. The study found that higher omega-3 fatty acid levels were associated with less decline in lung function for 15,063 participants. The omega-3 that provided the most benefit was the omega-3 fatty acid DHA. In plain English, the more the DHA levels increased over time, the more the decline in lung function was prevented. I know that sounds funny to say it “prevented decline” but to say that it improved lung function would be incorrect.

The Questions

In both studies, nutritional information wasn’t collected, or if it was collected, it wasn’t used in the statistical analyses performed. The assumption seems to be that seafood and plants were the primary sources of omega-3 fatty acids, and that may be true. But it raises a question about the potential for using omega-3s in dietary supplements. Would the same response occur in reducing the risk of chronic kidney disease as it did for the loss of lung function?

It also raises another question. Many studies on the benefits of omega-3 supplements on heart health and other organs are often less than overwhelming. Could it be that there is a nutrient or nutrients in fish that, together with omega-3s, could contribute to benefits? Or could it be there’s a factor that helps with digestion, absorption, and utilization in the actual form of omega-3s used as supplements? We don’t know at this time.

The Bottom Line

While the benefits of omega-3s, specifically DHA, were small, the fact that they prevented decline over years contributes to aging with a vengeance. I think having a diet that includes the regular intake of fatty fish is the key to a healthy lifestyle, and I still think regular use of fish oil supplements may prove to be beneficial as the research continues. I’ll keep you posted.

What are you prepared to do today?

        Dr. Chet

References:
1. Am J Respir Crit Care Med. 2023 Jul 20. doi: 10.1164/rccm.202301-0074OC
2. BMJ 2023;380:e072909. doi: 10.1136/bmj-2022-0729092

The Supplementation Sweet Spot, Part Two

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We’ve got the beginning of our sweet spot for supplementation started with a multivitamin-multimineral and probiotics; today I’ll finish it up with two more—depending.

Omega-3 Fatty Acids

Recommendations on the type of omega-3s seem to be in flux with disagreements over docosahexaenoic acid (DHA). The cause for concern seems to be the potential relationship between DHA and atrial fibrillation. I’m still not satisfied as to the relevancy of the risk in the general population with one exception: those people who’ve had myocardial infarctions (heart attacks) that resulted in the loss of heart muscle. For now, those people may want to be cautious. My research continues and when I have an answer, so will you.

Unless you regularly eat servings of cold-water fish two or three times a week, part of your foundation supplementation should be 1–3 grams of EPA, DHA, or the plant-sourced alpha linoleic acid (ALA), or a combination of all three. You can pick any body system, and omega-3s are most likely beneficial. This is especially true of the cardiovascular and nervous systems.

Vitamin D

The final foundation supplement that makes up our sweet spot is vitamin D but with a catch. Instead of taking massive amounts of vitamin D, the best way to determine whether you need to supplement with vitamin D is to get your blood levels checked via a 25 hydroxyvitamin D (25(OH)D) blood test. If you’re low in vitamin D, below 30 ng/mL, add more vitamin D to your supplements in 50 mcg (2,000 IU) increments until your blood level reaches 40–60 ng/mL. Obviously, you need to see your doctor for the test, but you should be seeing your doctor regularly anyway.

Depending on where you live, sunlight will help you maintain healthy vitamin D levels with about 15 minutes exposure per day. However, in Northern areas such as here in Grand Rapids, that only happens about half the year, so we make sure to take our vitamin D supplement and bump it up a little in winter.

More

Vitamin D has become controversial with the current COVID-19 outbreak. Vitamin D will not prevent you from catching COVID-19; it will help reduce the severity of symptoms. But megadosing on vitamin D can have consequences that can result in bone loss. That’s why basing your intake on a blood test is the right way to go.

The Bottom Line

There you have the sweet spot for foundation supplements that all of us need, regardless of the quality of our diet. What about all those other supplements out there? Fine tuning supplementation to meet your personal needs is where supplements get complicated and need to be personalized. With the billions of dollars spent on supplements every year, if everyone began with the sweet spot of foundation nutrients, everyone would be better off, just like the sweet spots for diet and exercise.

If you want to know more about the science behind these supplements as well as how to assess a quality manufacturer, get a digital copy of Supplementing Your Diet; if you want to pass along the information to others, get a 5-pack of CDs at reduced prices. They’re all on sale at 25% off, and that’s in addition to Member and Insider discounts. You can also find info on supplementation for other conditions such as high blood pressure, pregnancy, migraines, weight loss, and more at the Store at drchet.com.

What are you prepared to do today?

        Dr. Chet

Should People with CVD Take Omega-3s?

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Last time, I talked about some research that hasn’t been done to definitively know whether DHA contributes to arrhythmias or not, but I implied that there may be one issue that may have contributed to this latest study. Let’s talk about research bias.

Research Bias

Some of the researchers who examined the data from the longitudinal study I talked about on Tuesday were also involved in at least one of the clinical trials on Vascepa, the pharmaceutical form of EPA-only omega-3s. I know what you’re thinking: somehow they intentionally manipulated data so that it seemed DHA was bad. I wouldn’t assume that, because these are good scientists. However, there has to be an inherent bias—beliefs that set up space in your brain and affect your actions without you realizing it. Another way of stating this would be that you find what you look for. It would be very difficult to examine any data involving EPA, DHA, and cardiovascular disease and withhold bias. I don’t believe it was intentional, but I also believe that it could have influenced the results to some degree.

The INtermountain Healthcare Biological Samples Collection Project and Investigational Registry (INSPIRE for short) is not a randomized clinical trial; it’s an observational study. I’ve already talked about the data that are missing on diet, supplementation, and exercise. In addition, it’s a big stretch to suggest that 10 years after samples were taken during an angiographic procedure that the same distribution of EPA-DHA was maintained.

Prior Research

Let’s think about the studies from last week: they were test-tube studies. Those are the foundation you must build before you start doing animal testing; only after that do you get to human testing. One research group also did a study on rodents which demonstrated proof of possible benefit. Have we had that type of research on EPA and DHA as it relates to cardiovascular disease? I did find some.

There have been studies examining how omega-3s may positively affect heart rhythms. In studies on rodents and dogs, DHA but not EPA showed clear benefits on reducing atrial fibrillation and other forms of cardiovascular disease.

But when you examine research on humans, the data are conflicting. By that I mean that some studies show that higher DHA intake and/or levels are associated with the reduction of arrhythmias. Other more recent research shows that it may not. There’s simply not enough information to make a decision.

The Bottom Line

At this point, you have to be thinking “What the heck am I supposed to do?” I think that we stand in an area of research where we have to “reserve judgment,” or maybe it would be better to say to “reserve condemnation.” We just don’t have enough data to make an informed decision either way. I’ve illustrated some of the things that need to be answered as it relates to omega-3 intake, but there are many more questions.

So I’ll leave you with this. If you have had no signs or symptoms of cardiovascular disease, no matter your age, you can most likely continue taking the same omega-3 supplements you always have been. If you have had a heart attack with damage to the muscle tissue, that seems to be where the problem lies, but it isn’t the same for every person. I would have a discussion with your cardiologist before deciding whether to take just EPA or to continue taking combinations of EPA and DHA; that’s the prudent thing to do.

But as you make that decision, consider all the other benefits of omega-3s. A search for “omega-3” at drchet.com yields several pages of results. Very rarely in life do we have simple decisions to make; it’s always a balancing act between competing objectives and imperfect information, and this is another one of those situations.

What are you prepared to do today?

        Dr. Chet

References:
1. J Am Coll Cardiol. 2021 May, 77 (18_Supplement_1) 1453.
2. Vascul Pharmacol. 2016 Jul;82:11-9. doi: 10.1016/j.vph.2016.03.007.
3. Can J Physiol Pharmacol. 2016 Mar;94(3):309-23. doi: 10.1139/cjpp-2015-0300.
4. Circulation: Arrhythmia and Electrophysiology. 2012;5:978–983.

Omega-3s and Heart Disease

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In addition to the research papers on omega-3s I talked about last week, another paper was presented at the American College of Cardiology in May that suggests EPA seems to reduce cardiovascular disease (CVD), while DHA seems to neutralize the benefits. Let’s take a look at this recent study to see what they found.

I haven’t seen the data, just press releases of varying lengths; I’ve written the authors but haven’t heard back yet. The problem with this recent study is that it’s a retrospective examination of a large group of people. The data are part of an ongoing study (much like the All Of Us study in which I’m a volunteer) that secured blood and tissue samples of volunteers; the researchers use that data as well as access to the volunteers’ medical records. In this case, they assessed the EPA and DHA levels of the blood samples and the CVD events that occurred in a random sample of the volunteers over the years. That’s how they determined that the EPA was beneficial in reducing CVD and as DHA levels rose, the benefits were negated.

The primary problem is that the blood samples are a snapshot of one day in the life of the volunteers. We have no idea if they took dietary supplements or if they happened to eat a lot of fish or a lot of nuts and other foods with omega-3s. No other dietary data, no supplement data, no exercise data—all things that we know are related to the development of cardiovascular disease. I think there’s a significant factor at play in this data analysis, and I’ll give you that observation in Saturday’s memo.

What are you prepared to do today?

        Dr. Chet

Reference: Press Release: Warning: Combination of Omega-3s in Popular Supplements May Blunt Heart Benefits. Intermountain Medical Center May 17, 2021

The Bottom Line on Omega-3s

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When you consider the research studies I reviewed last week and this week on omega-3 fatty acids, they may seem confusing. The reason is that in both of those studies, they were looking at very specific outcomes. In last Thursday’s memo, it was changes in the quantity of specific cytokines, chemicals that are inflammatory in nature. In the study from Tuesday, it was for reduction of cardiac events. There are other ways that omega-3s can contribute to health, and I thought a little review would be in order.

Cellular Membranes

Cells seem to work better when they contain omega-3 fatty acids. Remember, a cell has an exterior wall of a lipid bilayer. If the diet contains a high amount of saturated fat, a high amount of saturated fat becomes part of that lipid bilayer. If the diet contains more omega-3 fatty acids, whether by eating fish or by taking a dietary supplement, the cell membranes contain a higher proportion of omega-3 fatty acids. While the mechanisms are not known, the cells seem to function better when they contain more omega-3s.

Let me give you a couple of examples. Nerve tissue seems to function better when there’s a high amount of DHA in the bloodstream; DHA supplementation seems to be beneficial for nerve problems such as migraine headaches, depression, and Parkinson’s disease. It’s not a cure, but somehow the omega-3s become integrated into those nerve cells and they work better. The same holds true for the eyes; vision is dependent on the nervous system to operate properly, and high DHA appears to benefit eye health as well.

Hormone Control

The study I reviewed last Thursday focused on one type of inflammatory chemicals called the cytokines, but there are other pro-inflammatory hormones that may be better controlled with both high EPA and DHA supplementation. Cortisol is a known stress hormone. In times like we’re experiencing now and for those who are overweight or obese, cortisol levels are higher; that may be due to the increased presence of saturated fat. If omega-3s become part of triglycerides, the potential for inflammatory hormones such as cortisol can be decreased.

There’s also the possibility that persistent use of both EPA and DHA reduces atherosclerotic plaque, the hard layer of fat that builds up in arteries, or it may prevent cholesterol from being manufactured in the first place. While it’s too long of a process to explain in a Memo, our bodies make cholesterol two carbon molecules at a time. When there’s a higher amount of saturated fat, the process can speed along unabated; but when there’s a high percentage of omega-3 fatty acids present, the process gets interrupted. We don’t know the mechanisms; we just know omega-3s help.

The Bottom Line

Those are some of the possible ways omega-3 fatty acids are used for our health. Undoubtedly there are many more that haven’t been discovered or haven’t been examined in enough clinical trials at this point. The most important thing for you and me is to make sure that either we eat several servings of fatty fish per week or we take up to four grams of high EPA-DHA omega-3 supplements every day—let the science work it out later. Our job is to provide our body with nutrients that are beneficial.

What are you prepared to do today?

        Dr. Chet

Can Omega-3s Reduce Inflammation?

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Omega-3 fatty acids have been in the science news this week. In this Memo, I’ll take a look at a small study that examined the effects of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) on specific markers of inflammation in 21 subjects between 50 and 75 who had elevated levels of inflammation. Researchers had subjects follow a particular regimen: take three grams of either DHA or EPA for 10 weeks, cease all omega-3s for 10 weeks, and then take three grams of the other omega-3.

The study showed both omega-3s were effective; they just worked differently, and I can’t explain that without getting technical. It seemed that DHA reduced specific cytokines such as TNF-alpha, IL-6, and IL-10 to a greater degree than did EPA. One of the ways that may have happened was a reduction or replacement of the proinflammatory omega-6 arachidonic acid. The important point is this: however they worked and although they worked in different ways, both DHA and EPA were effective in reducing the inflammatory response in this small study.

Could adding high-DHA fish oil supplements to the diet reduce cytokine production in every case? Specifically, could it potentially have some benefit for the cytokine storm that’s associated with severe cases of COVID-19? We don’t know that yet because that specific research hasn’t been done. But since there are so many other well-documented benefits of omega-3s, make sure you regularly eat fatty fish or take fish oil supplements with DHA and EPA. It’s always a good bet.

What are you prepared to do today?

        Dr. Chet

Reference: DOI:https://doi.org/10.1016/j.atherosclerosis.2020.11.018

Fish Oil: Medication versus Supplements

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Before I address the concerns about fish oil supplements put forth by the Vascepa® prescription omega-3 website, it’s important to understand that all prescription and over-the-counter medications have been approved by the U.S. Food and Drug Administration (FDA). That means they have spent a significant amount of money—sometimes over $1 billion—to prove that the treatment claims are significant, and you can’t take that away from them. But marketing is a different story, so let’s look at what they say.

“Fish oil supplements are not FDA-approved.” True; no dietary supplement is FDA-approved, but that doesn’t mean they’re not regulated. They also can’t make claims about curing diseases.

“Daily dose could require 10 to 40 capsules to equal the prescription EPA omega-3.” That depends on the brand purchased, so that critique is weak.

“Fish oil supplements can leave a fish-y aftertaste.” Really? It’s fish oil, what would you expect? (Keeping the supplements in the refrigerator may help with that as well as taking fish oil before meals.) They suggest that the oils turn rancid and that causes the taste, but they offer no proof of that claim.

The last critique they make of fish oil supplements is that “Many contain another omega-3 fatty acid called DHA.” They say DHA can raise LDL cholesterol. I’ll address that claim and provide some concerns I have with the prescription omega-3 and how it’s being marketed on Saturday.

What are you prepared to do today?

        Dr. Chet

What You Need to Know About Omega-3s

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This week I’m covering basic information about three supplements.  One of my favorites and one I don’t ever leave home without is omega-3 fatty acids.

There are three basic forms of omega-3 fatty acids: eicosapentanoic acid or EPA, docosahexaenoic acid or DHA, and alpha-linolenic acid or ALA. The body cannot make omega-3 fatty acids, so they have to come from food and supplements. ALA is an essential fatty acid—the body can make EPA and DHA from it but not very well—so getting EPA and DHA from diet and supplements is critical.

EPA . . .

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