Vegan Diets Linked with Lower Heart-Health Promoting Omega-3 Fatty Acids in Cell Membranes, Study Finds

A new study finds vegan dieters have higher concentrations of omega-6 fatty acids and lower quantities of health-promoting omega-3 fatty acids, including pro-resolving lipid mediators, in their cell membranes when compared to omnivores.

Resolvins are bioactive lipids made from dietary omega-3 fatty acids that help resolve inflammation.

Resolvins were not detected in the plasma of any vegan subjects, whereas nine out of twenty-four omnivores had detectable concentrations.

Studies Mentioned:

Pinto, A. M. et al. A comparison of heart rate variability, n-3 PUFA status and lipid mediator profile in age- and BMI-matched middle-aged vegans and omnivores. Br. J. Nutr. 117, 669–685 (2017).

Burns-Whitmore, B., Froyen, E., Heskey, C., Parker, T. & Pablo, G. S. Alpha-Linolenic and Linoleic Fatty Acids in the Vegan Diet: Do They Require Dietary Reference Intake/Adequate Intake Special Consideration? Nutrients 11, 2365 (2019).

Haider, S., Sima, A., Kühn, T. & Wakolbinger, M. The Association between Vegan Dietary Patterns and Physical Activity—A Cross-Sectional Online Survey. Nutrients 15, 1847 (2023).
Gallagher, C. T., Hanley, P. & Lane, K. E. Pattern analysis of vegan eating reveals healthy and unhealthy patterns within the vegan diet. Public Heal. Nutr. 25, 1310–1320 (2022).
Walther, B. et al. Comparison of nutritional composition between plant-based drinks and cow’s milk. Front. Nutr. 9, 988707 (2022).

Video Time Stamps:

0:00 Intro

0:17 Vegan VS Omnivore health-promoting omega-3 fatty acids

0:36 Omega-3 Index

0:50 HRV in Vegan VS Omnivore

1:32 Main takeaway

2:10 Linoleic acid decreases conversion of Omega-3

3:42 Importance of your omega-3 index

4:10 HRV in vegans VS Omnivores

5:10 Omega-3 Index and HRV

6:04 Seed oils lower conversion of ALA to EPA and DHA

6:31 Main findings

7:30 ALA conversion is low

8:02 Creatine is low in vegan dieters

9:57 LISTEN TO THIS!

Video Captions:

According to the media, and mainstream medical doctors, going on a vegan diet is the best thing you can do to support cardiometabolic health. But a recently published study found that there's different concentrations of health-promoting omega-3 fatty acid metabolites, in vegans versus omnivores, as well as changes in heart rate variability, and the omega-3 index, as well as concentrations of pro-resolving mediators which are key anti-inflammatory mediators, that might help to reduce cardiometabolic health risk.

So we're gonna talk about this study in greater detail. It didn't get a lot of media attention, but it's something you should be aware about. If you've been on a vegan diet for an extended period of time, you might want to consider testing your omega-3 index, and possibly supporting your levels of omega-3s, specifically DHA, as well as EPA, because these studies, this study actually, compared vegans, and these are people that were on a vegan or vegetarian diet for more than two years, compared to healthy people who were on an omnivorous diet for more than two years. And they found differences in heart rate variability, as well as concentrations of EPA, DHA, and high levels of linoleic acid, in the vegan dieters.

So it's important to recognize that low heart rate variability predicts sudden cardiac death. Long-chain omega-3 polyunsaturated fat status is positively associated with heart rate variability. This cross-sectional study investigated whether the vegans between the ages of 40 and 70 years old, whose diets are naturally free of EPA and DHA, have lower HRV compared with omnivores.

Proportions of long-chain polyunsaturated omega-3 fats, in both the red blood cell, as well as plasma fatty acid concentrations, as well as plasma concentration of long chain polyunsaturated omega-3 derived lipid mediators, were significantly lower in vegans, as well as daytime heart rate variability was actually lower in vegans, compared to omnivores.

So again, this is important, because we hear that going on a plant-based diet is the best thing you can do for your health, but we're not hearing so much about the nuances, and the considerations, especially if you've been vegan for an extended period of time.

Now, where we're gonna go in this conversation, is first talk about the importance of heart rate variability, the importance of the omega-3 index, and then we're gonna break down the key findings in the red blood cell fatty acid profile, as well as plasma fatty acid profile, between the vegans and the omnivores. Now, it shouldn't surprise you that most vegans are consuming a higher amount of processed foods, or foods containing linoleic acid, which is an omega-6 derived oil, primarily derived from soy, from canola, from sunflower.

We know that the omega-6 linoleic acid actually inhibits the conversion of ALA, alpha linoleic acid, to help health-promoting EPA, and DHA, what's needless to say, DHA, as well as EPA, have anti-inflammatory effects, and they are converted to pro-resolving mediators. And these are anti-inflammatory molecules that resolve inflammation. It's important to acknowledge, in this study, they found that there were zero levels of the pro-resolving mediator metabolites in the vegan dieters, compared to omnivores. Also, the omega-3 index levels were less than half in the vegans, compared to the omnivores.

So you might say, “Who cares about the omega-3 index, Mike, “I don't know about that. “I care about my cholesterol.” Well, you really should care about your omega-3 index, because scientific studies show that people with a low omega-3 index, below six percent, are at significantly higher risk of having a sudden cardiac event, and all-cause mortality.

We interviewed several years ago, Dr. Bill Harris. He's talked about this extensively. Dr. Peter Attia and many other folks have talked about the importance of the omega-3 index. So there's a $49 test. We actually happen to sell this over at myoxcience.com. I'm not promoting that. You can check that out if you're interested. I was personally interested, and tested mine. It was about seven percent, and that was not with supplementation of omega-3 fats. But I was unaware of the differences between omnivorous diet, and a vegan diet. And so if you've been a vegan for a long time, and especially if you're planning on having children, or you're worried about your cardiometabolic health, you may wanna consider testing your omega-3 index. And if it's under six percent, you should probably supplement, or have more fatty fish, cold water, fatty fish, like wild caught salmon.

Let's talk about the heart rate variability, because there appears to be a link between omega-3 fatty acid status, and heart rate variability. The scientists say vegans had higher overall HRV, as measured by 24-hour standard deviation of the normal beat-to-beat intervals here, known as the SDNN. Conversely, vegans presented with a decreased, eight-hour daytime HRV, meaning that the vegans had slightly higher HRV, over the 24-hour period, but for some reason, during the day, vegans had a lower HRV. Now it's important to recognize that most cardiovascular events, like having a heart attack, or a myocardial infarction, actually happen during the daytime, in the early morning hours. So that is worth considering. Now the scientists were curious to see if there was an association between omega-3 fatty acid status, in the plasma, and the red blood cell, and its correlation with HRV.

The scientists say, “Vegans may have reduced availability “of precursor molecules, for pro-resolving lipid mediators. “It remains to be determined “whether there's a direct link “with impaired cardiac function, “in populations with lower omega-3 fatty acid status.”

Here's why HRV matters: Low HRV, or heart rate variability, is associated with mortality after a myocardial infarction, and increased risk of cardiac events in the general population. Associations between increased omega-3 fatty acid consumption, and higher heart rate variability, and lower heart rate, suggests that populations with very low intake of omega-3 polyunsaturated fatty acid status, might be at greater risk for rhythmic events, and sudden cardiac death.

Now let's talk about the fatty acid differences. I think this is really important to recognize. Again, I'll link that episode with Dr. Bill Harris. We also talked with his daughter, who speaks extensively on the health benefits of DHA, which we're gonna get into very soon. And this is particularly important for newborn mothers, because we know that DHA from the maternal side, is really important for the baby, 'cause it's transported through breast milk. And I'll share with you more details on that in a moment.

The scientists say that low omega-3 index is linked with higher risk for sudden cardiac death and all-cause mortality. Diets high in linoleic acid, this is from mostly the industrial seed oils, cotton, canola, we know that sunflower oil, as well as soy oil. And this decreases the conversion from alpha linoleic acid, to EPA and DHA. So that is, if you're consuming a lot of industrial seed oils, that actually reduces the already low conversion, from say flax or or borage oil, even there's a little alpha-linoleic and maybe eggs and so forth, there's a decreased conversion from ALA to EPA, and DHA.

If you're consuming a lot of linoleic acid. And I'll share with you the profiles here soon. Vegans had significantly higher blood levels, and red blood cell fatty acid levels of linoleic acid. The scientists say the main omega-3 polyunsaturated fat in vegan diets, is alphalinoleic acid, known as 18:3n-3, derived from plant foods, particularly soy and seed oil such as canola oil. The omega-3 polyunsaturated fatty acids, as a percentage of total fatty acid in blood fractions, are, in vegans, only a third of the level, in meat and fish eaters. So that's important to acknowledge. Here's yet another study. This was in the “Current Opinion in Clinical Nutrition and Metabolic Care,” “The Omega-3 Index is a prognosis tool “in cardiovascular disease.” And what they say is that the omega-3 index was described as the sum total of EPA, and DHA, in red blood cells, and it's an index of coronary heart disease mortality. And this review really dives into the details, if you wanna dive more into that.

Another study published in 2019, in the journal “Nutrients,” titled, “Alphalinoleic Acid and Linoleic Fatty Acids “in the Vegan Diet: “Do They Require Dietary Reference Intake, “Adequate Intake, Special Consideration?” They say that vegan diets are high in alphalinoleic acid, which is an omega-3. People think it's health-promoting. But again, the rates of conversion of ALA, alphalinoleic acid to EPA and DHA, is between four percent in men, up to nine percent in women, which is further reduced, the more linoleic acid you consume. So if you're having a lot of canola, a lot of sunflower, a lot of soy oil, that means that the omega-3s you're getting from ALA, is being reduced. And we want those to be converted into EPA, and DHA, particularly if you wanna have children.

So there's a lot of nutritional considerations, if you're on a vegan diet, especially when it comes to if you're a vegan athlete, because one nutrient that is not found in plants, is creatine. That's why at Myoxcience, we have the creatine-containing Electrolyte Sticks, which is the only product on the market featuring real salt, taurine, creatine, as well as albion chelated minerals. There's over 659 reviews over at Myoxcience.com, from people like you, who are trying to get more mileage from their exercise sessions, particularly in hot, humid environments. We know that creatine increases total body water, and intracellular water. When it's paired with electrolytes, it actually enhances the absorption. So this novel formulation can be used before your workouts, or during your workouts, to enhance exercise performance, as well as hydration. You can save, using the code podcast over at myoxcience.com. That's M-Y-O-X-C-I-E-N-C-E.com. Again, vegan and vegetarian diets are devoid of creatine, as well as taurine, so you can help to support your athletic performance, by checking out the Electrolyte Sticks by Myoxcience.

Now going back to the details of the study, let's look at the fatty acid profiles, and first talk about what the scientists hypothesize. The study aims to compare heart rate variability, between vegans and omnivores, matched for age, sex, BMI, and health status. And their primary hypothesis was that the vegans have higher heart rate variability, and shorter inter-beat intervals, and lower HRV, compared to omnivores. Now, it's important to recognize that you want a lower heart rate, and a higher heart rate variability. I know that variability sounds a little wonky. We've done many videos on heart rate variability before, and the benefits there.

Marco Altini, we talked a lot about that. He has a great app if you wanna get into heart rate variability testing. There's all sorts of technologies out there. Low heart rate, high heart rate variability. So the HRV is a more, it's a reflection of your autonomic nervous system tone. Having a higher parasympathetic tone is favorable, it's adaptive, and it's linked with a better, more resilient stress response. And so again, the scientists are trying to suss out whether or not the concentration of the omega-3 fats in the diet, impacts HRV, as well as cardiometabolic health. So what did the scientists find? They say, “In general, the lipid mediators “derived from the polyunsaturated omega-6 fats, “and plant-derived omega-3 fats, “were higher in vegans compared with omnivores. “And the mediators derived from the DHA, and EPA, “were lower in vegans compared with omnivores, “showing a clear difference in lipidomic profiles, “between the two groups.”

Here is the plasma fatty acid differences. This is just incredibly fascinating. I know there's a lot of numbers here. So let's focus on linoleic acid, EPA, and DHA. Then we're gonna talk about the red blood cell, Then we're gonna talk about the changes in the pro-resolving mediators, which is really fascinating. SPMS, and specific pro-resolving mediators, and and all the derivatives of DHA, the health promoting doca, sachs, enoic acid, the long-chain polyunsaturated omega-3 fat. Incredibly fascinating. There were zero levels in the vegans. And I'm not, you know, bashing on vegans. I think this is just something that most vegans are unaware of. They just focus on the big picture.

They think, oh, plants are good, animals are bad, and they do not consider the nuances here, which is important to acknowledge. So let's look at linoleic acid. You see here, and this is just plasma as a percentage. The percent of linoleic acid in the omnivores was 27%. In contrast to the vegans, it was 33%. Now remember, the more linoleic acid you have, that reduces the conversion of alpha linolinic, to EPA-DHA, which is not a good thing.

Now let's look at the EPA and DHA. What you see here are significant differences in both EPA, and DHA in the plasma. But I really care more about the erythrocyte, or the red blood cell. So let's look at the red blood cell levels of linoleic acid. Obviously, it's significantly higher in the vegans, compared to the omnivores. And let's look at the EPA. The levels of EPA, as a percentage, in the red blood cell, in omnivores, is 1.26%, compared to just 0.67% in the vegans. Now what about the DHA? Now we really, we care about DHA, because of all of the metabolites of DHA, that resolve inflammation.

So the levels of DHA, if you look at the omnivores, the levels of DHA are 2.62, and only 2.15 in the vegans. Now why does that really matter? Because we know that the metabolites of DHA, and EPA, get metabolized into all of these pro-resolving metabolites, which are essentially, there's a dearth of these, in the vegan.

Now here's the figure we really care about, because we want to reduce chronic inflammation. Now comparing the levels of the pro-resolving mediator metabolites, in the omnivores, compared to the vegans, you can really start to see the differences here, where the vegans had zero percent of many key important pro-resolving mediator metabolites, derived from both EPA, and DHA. And so you can see here, I'm not gonna name all these different compounds, because they get really jargonistic. But many of the important pro-resolving mediator metabolites are significantly lower in the vegans, or completely absent, in comparison to the omnivores, which I think is really important.

So the scientists say, “As expected, we observe marked differences “in vegans and omnivores, “in their omega-3 fatty acid profile status, as represented “by their red blood cell fatty acid composition. “These findings were supported “by differences in the plasma fatty acid profile, “and self-reported dietary intake, “of polyunsaturated omega-3 fats. “The average red blood cell omega-3 index “and the omnivore group, “was lower than indices previously reported “for meat and fish-eating UK populations. “But differences between the groups studied here “were clear cut: inverse relationships were observed “for red blood cell, linoleic acid, “and the ratios of linoleic acid to EPA-DHA. “This supports existing evidence “that higher dietary intakes of linoleic acid, “the omega-6 polyunsaturated PUFA, “which is abundant in the omnivore diet, “but even more so in the vegan vegetarian diet, “and might inhibit the conversion of alphalinoleic acid “to the health-promoting omega-3 polyunsaturated fats “EPA, and DHA.” Now, when it comes to heart rate and heart rate variability, the scientists say that, “The daytime heart rate was higher, “and the beat-to-beat variability, “also known as the heart rate, “was shorter, or lower in the vegans, “even following adjustment “for physical activity during the same eight hour period. “These observations might indicate “that a lower omega-3 fatty acid status “could lead to either predominance “of a sympathetic regulation, “or a greater withdrawal of parasympathetic “nervous system activity, “or possibly due to depletion “of polyunsaturated omega-3 fats, “and cardiomyocyte membranes. “There is greater stimulation of pacemaker activity, “despite a normal sympathetic neural transmission “during waking hours.” So essentially, what the scientists are talking about here, is the changes in the key levels of these health-promoting omega-3 fatty acid metabolites, might affect the heart, and heart rate variability, although the direction of causality is yet to be sussed out.

That's important to acknowledge, because we know that a higher omega-3 index is linked with lower incidences of fatal myocardial infarction. The scientists also say that notably in vegans, there remarkably lower fasting plasma concentrations of HEPA, which is of really important anti-inflammatory, pro-resolving mediator metabolites. And there were undetectable concentrations of multiple pro-resolving mediators derived from DHA, which is also important.

They say, “In summary, these data show that vegans “have increased blood concentrations of linoleic acid, “compared to omnivores, “and/or very low or undetectable concentrations “of long-chain polyunsaturated omega-3 fats, “and these resolvins.” So that's important to acknowledge, if you're going on a vegan diet. If you've been on a vegan diet, especially if you want to have children, or you're worried about your mental health, and cardiovascular health, at least consider having fatty fish, and at the bare minimum, supplement with omega-3 fats. Consider testing your omega-3 index. I'll put links in the description below, and a coupon code over at myoxcience.com. This is what we offer through OmegaQuant.

This is a great test to do every couple years, to see if you're getting ample levels of the long-chain omega-3 polyunsaturated fats, that are known to be health promoting, because they're metabolized into anti-inflammatory metabolites, which as this study found, are undetectable in vegans. So that's important to acknowledge, and really important for mothers-to-be, and people who are trying to conceive children, and produce inflammation in their body. That's it for today, friends. Hopefully you found this information helpful. I will link this study, and the other studies that we talked about, in the description below. I appreciate you hitting that like button leaving a comment, and sharing this video with someone who might find this information helpful. We'll catch you on a future one down the road.