Do B Vitamins Reduce Heart Disease Risk?

Written by Dr. Steve Chaney on . Posted in current health articles, Drugs and Health, Health Current Events, Healthy Lifestyle, Supplements and Health, Vitamins and Health

What Role Do B Vitamins Play in a Heart Healthy Lifestyle?

Author: Dr. Stephen Chaney

b vitamins reduce heart attack riskTwo weeks ago I shared some studies that challenge the claim that vitamin E doesn’t reduce heart attack risk. To close out “Heart Health” month, I want to share some information that may change how you think about B vitamins and heart disease risk. Once again, you’ve seen the headlines: “B Vitamins Do Not Reduce the Risk of Heart Disease”. In fact, these headlines have been repeated so many times that virtually every expert thinks that it has to be true. Once again, I’m going to share some information with you that I learned from a seminar by Dr. Jeffrey Blumberg who disagrees with this commonly held belief.

Dr. Blumberg is a Professor in the Friedman School ofNutrition Science and Policy at Tufts. Dr. Blumberg has over 200 publications in peer-reviewed scientific journals. He is considered one of the world’s top experts on supplementation, and his specialty is conducting and analyzing clinical studies. He believes that the media has seriously misinterpreted the studies on B vitamins and heart disease risk. You might call this “The Rest of the Story” because you (and your doctor) definitely did not hear this part of the story in the news.

Do B Vitamins Reduce Heart Disease Risk?

heart disease in menThe study in question is called the “Heart Outcomes Prevention Evaluation-2“. In that study a group of middle aged men and women received 2.5 mg of folate, 50 mg of vitamin B6 and 1 mg of vitamin B12 versus a placebo and were followed for an average of 5 years.

The headlines that you may have seen said “B vitamins do not reduce the risk of major cardiovascular events in patients with vascular disease”. But, the headlines did not tell the whole story.

In the first place, that was only true for heart attacks and cardiovascular death. Strokes were reduced by 25%. I don’t know about you, but I consider strokes to be fairly major.

However, even when we focus on heart attacks and cardiovascular deaths the headlines didn’t tell the whole story. You see, even the best intentioned studies sometimes contain fatal flaws that aren’t obvious until after the study has been completed.

The Flaws In The Study

flawsThere were two major flaws in this study.

Flaw #1 was that 70% of the study subjects were eating foods fortified with folate and had adequate levels of that nutrient in their bloodstream before the study started.

For those people who were already getting enough folate in their diet, B vitamin supplementation didn’t make much of a difference. However, for those people not getting adequate levels of folate in their diet, B vitamin supplementation decreased their risk of heart disease by ~15%.

Flaw #2 was that ~90% of the people in the study had a history of coronary artery disease and most of them were already on cholesterol lowering medications.

To understand why this is a problem you have to understand both the proposed mechanism by which B vitamin supplementation has been proposed to lower the risk of heart disease AND how the cholesterol lowering drugs work.

Deficiencies of folate, B6 and B12 are thought to increase the risk of heart disease because the B vitamin deficiency causes an increase in homocysteinelevels in the blood, and high homocysteine levels are thought to increase inflammation – which is a risk factor for heart disease.  So supplementation with folate, B6 and B12 has been proposed to decrease heart disease risk by decreasing inflammation.

The problem is that the most commonly used cholesterol lowering medications also decrease inflammation.So you might not be surprised to learn that those people who had a history of coronary artery disease(and were taking cholesterol lowering medication that reduces inflammation) did not receive much additional benefit from B vitamin supplementation.

For those people in the study who were not taking cholesterol lowering medication, B vitamin supplementation also reduced their risk of heart attacks by ~15% – but there were too few people in that group for the results to be statistically significant.

So the headlines from this study really should have said “B vitamins do not reduce the risk of heart attacks or cardiovascular deaths in people who are already getting adequate folate from their diet or in people who are taking drugs that reduce the bad effects of B vitamin deficiency”. But that kind of headline just wouldn’t sell any newspapers.

What Does This Study Mean For You?

There are two very important take-home lessons from this study.

Lesson #1:  Once again this study makes the point that supplementation makes the biggest difference when people have an increased need. The studies discussed in Vitamin E and Heart Disease  two weeks ago illustrated increased need because of age, pre-existing disease, and genetic predisposition. This study illustrated increased need because of inadequate diet.

Lesson #2:  This study also illustrates a problem that is becoming increasingly common in studies of supplementation. It is considered unethical to not provide participants in both groups with what is considered the standard of care for medical practice. In today’s world the standard of care includes multiple drugs with multiple side effects, and some of those drugs may have the same mechanism of action as the supplement.

I have discussed this problem in the context of omega-3 fatty acids and heart disease in a previous “Health Tips From the Professor,”  Is Fish Oil Really Snake Oil?   In many cases it is no longer possible to ask whether supplement X reduces the risk of a particular disease. It is now only possible to ask whether supplement X provides any additional benefit for patients who are taking multiple drugs, with multiple side effects. That’s not the question that many of my readers are interested in.

 

The Bottom Line

  • Headlines have proclaimed for years the “B Vitamins Do Not Reduce Heart Disease Risk”. Dr. Jeffrey Bloomberg of Tufts University has reviewed one of the major studies behind this claim and found the headlines to be misleading.
  • For example, the study showed that B vitamin supplementation reduced strokes by 25%, which is a pretty significant finding in itself.
  • When he analyzed the portion of the study looking at heart attacks, he found two major flaws:

#1:  70% of the people in the study were already getting adequate amounts of B vitamins from their diet and would not be expected to benefit from supplementation. For the 30% who weren’t getting adequate amounts of B vitamins from their diet, supplementation reduced their risk of heart attack by 15%.

#2:  90% of the people in the study were taking a drug that masks the beneficial effects of B vitamin supplementation. For the 10% who weren’t taking the drug, supplementation with B vitamins also reduced their risk of heart attack by 15%, but there were too few people in that group for the results to be statistically significant.

Obviously, there were only a handful of people in the study who weren’t getting enough B vitamins from their diet AND weren’t on medication, so we have no idea what the effect of B vitamin supplementation was in that group.

  • Once again this study makes the point that supplementation makes the biggest difference when people have an increased need. The studies discussed in “Health Tips From the Professor” two weeks ago illustrated increased need because of age, pre-existing disease, and genetic predisposition. This study illustrated increased need because of inadequate diet.
  • This study also illustrates a problem that is becoming increasingly common in studies of supplementation. It is considered unethical to not provide participants in both groups with what is considered the standard of care for medical practice. In today’s world the standard of care includes multiple drugs, some of which may have the same mechanism of action as the supplement.

In many cases it is no longer possible to ask whether supplement X reduces the risk of a particular disease. It is now only possible to ask whether supplement X provides any additional benefit for patients who are taking multiple drugs, with multiple side effects. That’s not the question that many of my readers are interested in.

 

These statements have not been evaluated by the Food and Drug Administration. This information is not intended to diagnose, treat, cure or prevent any disease.

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Do Omega-3s Lower Blood Pressure in Young, Healthy Adults?

Posted August 14, 2018 by Dr. Steve Chaney

What Is The Omega-3 Index And Why Is It Important?

Author: Dr. Stephen Chaney

 

Do omega-3s lower blood pressure in healthy adults?

omega-3s lower blood pressure young adultsThe literature on the potential health benefits of omega-3s is very confusing. That’s because a lot of bad studies have been published. Many of them never determined the omega-3 status of their subjects prior to omega-3 supplementation. Others relied on dietary recalls of fish consumption, which can be inaccurate.

Fortunately, a much more accurate measure of omega-3 status has been developed and validated in recent years. It’s called the Omega-3 Index. Simply put, the Omega-3 Index is the percentage of EPA and DHA compared to 26 other fatty acids found in cellular membranes. Using modern technology, it can be determined from a single finger prick blood sample. It is a very accurate reflection of omega-3 intake relative to other fats in the diet over the past few months. More importantly, it is a measure of the omega-3 content of your cell membranes, which is a direct measure of your omega-3 nutritional status.

A recent extension of the Framingham Heart Study reported that participants with an Omega-3 Index >6.8% had a 39% lower risk of cardiovascular disease than those with an Omega-3 Index <4.2% (WS Harris et al, Journal of Clinical Lipidology, 12: 718-724, 2018 ). Although more work needs to be done, an Omega-3 Index of 4% or less is generally considered indicative of high cardiovascular risk, while 8% or better is considered indicative of low cardiovascular risk. For reference, the average American has an Omega-3 Index in the 4-5% range. In Japan, where fish consumption is much higher and cardiovascular risk much lower, the Omega-3 Index is in the 9-11% range.

Previous studies have suggested that omega-3 fatty acids lower blood pressure to a modest extent. Thus, it is not surprising that more recent studies have shown an inverse correlation between Omega-3 Index and blood pressure. However, those studies have been done with older populations, many of whom had already developed high blood pressure.

From a public health point of view, it is much more interesting to investigate whether it might be possible to prevent high blood pressure in older adults by optimizing omega-3 intake in a young, healthy population, most of whom had not yet developed high blood pressure. Unfortunately, there were no studies looking at that population. The current study was designed to fill that gap.

 

How Was The Study Done?

omega-3s lower blood pressure young healthy adultsThe current study (M.G. Filipovic et al, Journal of Hypertension, 36: 1548-1554, 2018 ) was based on data collected from 2036 healthy adults, aged 25-41, from Liechtenstein. They were participants in the GAPP (Genetic and Phenotypic Determinants of Blood Pressure) study. Participants were excluded from the study if they had been diagnosed with high blood pressure and were taking medication to lower their blood pressure. They were also excluded if they had heart disease, chronic kidney disease, other severe illnesses, obesity, sleep apnea, or daily use of non-steroidal anti-inflammatory medications.

Blood samples were collected at the time of their enrollment in the study and frozen for subsequent determination of Omega-3 Index. Blood pressure was also measured at their time of enrollment in two different ways. The first was a standard blood pressure measurement in a doctor’s office.

For the second measurement they were given a wearable blood pressure monitor that recorded their blood pressure over 24 hours every 15 minutes during the day and every 30 minutes while they were sleeping. This is considered more accurate than a resting blood pressure measurement in a doctor’s office because it records the variation in blood pressure, while you are sleeping, while you are exercising, and while you go about your everyday activities.

 

Do Omega-3s Lower Blood Pressure In Young, Healthy Adults?

omega-3s lower blood pressure young adults equipmentNone of the participants in the study had significantly elevated blood pressure. The mean systolic and diastolic office blood pressures were 120±13 and 78±9 respectively. The average Omega-3 Index in this population was 4.6%, which is similar to the average Omega-3 Index in the United States.

When they compared the group with the highest Omega-3 Index (average = 5.8%) with the group with the lowest Omega-3 Index (average = 4.6%):

  • The office measurement of systolic and diastolic blood pressure was decreased by 3.3% and 2.6% respectively
  • While those numbers appear small, the differences were highly significant.
  • The 24-hour blood pressure measurements showed a similar decrease.
  • Blood pressure measurements decreased linearly with increasing Omega-3 Index. [In studies of this kind, a linear dose-response is considered an internal validation of the differences observed between the group with the highest Omega-3 Index and the group with the lowest Omega-3 Index.]

The authors concluded: “A higher Omega-3 Index is associated with statistically significant, clinically relevant, lower systolic and diastolic blood pressure in normotensive, young and healthy individuals. Diets rich omega-3 fatty acids may be a strategy for primary prevention of hypertension.”

 

What Does This Mean For You?

omega-3s lower blood pressure young adults questionPerhaps I should first comment on the significance of the relatively small decrease in blood pressure observed in this study.

  • These were young adults, all of whom had normal or near normal blood pressure.
  • The difference in Omega-3 Index was rather small (5.8% to 4.6%). None of the participants in the study were at the 8% or above that is considered optimal.
  • Liechtenstein is a small country located between Switzerland and Spain. Fish consumption is low and omega-3 supplement consumption is rare.

Under these conditions, even a small, but statistically significant, decrease in blood pressure is remarkable.

We should think of this study as the start of the investigation of the relationship between omega-3 status and blood pressure. Its weakness is that it only shows an association between high Omega-3 Index and low blood pressure. It does not prove cause and effect.

Its strength is that it is consistent with many other studies showing omega-3 fatty acids lower blood pressure. Furthermore, it suggests that the effect of omega-3s on blood pressure may also be seen in young, healthy adults who have not yet developed high blood pressure.

Finally, the authors suggested that a diet rich in omega-3s might reduce the incidence of high blood pressure by slowing the age-related increase in blood pressure that most Americans experience. This idea is logical, but speculative at present.

However, the GAPP study is designed to provide the answer to that question. It is a long-term study with follow-up examinations scheduled every 3-5 years. It will be interesting to see whether the author’s prediction holds true, and a higher Omega-3 Index is associated with a slower increase in blood pressure as the participants age.

 

Why Is The Omega-3 Index Important?

 

The authors of this study said: “The Omega-3 Index is very robust to short-term intake of omega-3 fatty acids and reliably reflects an individual’s long-term omega-3 status and tissue omega-3 content. Therefore, the Omega-3 Index has the potential to become a cardiovascular risk factor as much as the HbA1c is for people with diabetes…” That is a bit of an overstatement. HbA1c is a measure of disease progression for diabetes because it is a direct measure of blood sugar control.

In contrast, Omega-3 Index is merely a risk factor for cardiovascular disease. However, if it is further validated by future studies, it is likely to be as important for predicting cardiovascular risk as are cholesterol levels and markers of inflammation.

However, to me the most important role of Omega-3 Index is in the design of future clinical studies. If anyone really wants to determine whether omega-3 supplementation reduces cardiovascular risk, high blood pressure, diabetes or any other health outcome they should:

  • Start with a population group with an Omega-3 Index in the deficient (4-5%) range.
  • Supplement with omega-3 fatty acids in a double blind, placebo-controlled manner.
  • Show that supplementation brought participants up to an optimal Omega-3 Index of 8% or greater.
  • Look at health outcomes such as heart attacks, cardiovascular deaths, hypertension, stroke, or depression.
  • Continue the study long enough for the beneficial effects of omega-3 supplementation to be measurable. For cardiovascular outcomes the American Heart Association has stated that at least two years are required to obtain meaningful results.

These are the kind of experiments that will be required to give definitive, reproducible results and resolve the confusion about the health effects of omega-3 fatty acids.

 

The Bottom Line

 

An accurate measure of omega-3 status has been developed and validated in recent years. It’s called the Omega-3 Index. Simply put, the Omega-3 Index is the percentage of EPA and DHA compared to 26 other fatty acids found in cellular membranes.

Although more work needs to be done, an Omega-3 Index of 4% or less is generally considered indicative of high cardiovascular risk while 8% or better is considered indicative of low cardiovascular risk.

Previous studies have shown an inverse correlation between Omega-3 Index and blood pressure. However, these studies have been done with older populations, many of whom had already developed high blood pressure.

From a public health point of view, it is much more interesting to investigate whether it might be possible to prevent high blood pressure in older adults by optimizing omega-3 intake in a young, healthy population, most of whom had not yet developed high blood pressure. Until now, there have been no studies looking at that population.

The study described in this article was designed to fill that gap. The participants in this study were ages 25-41, were healthy, and none of them had elevated blood pressure.

When the group with the highest Omega-3 Index (average = 5.8%) was compared with the group with the lowest Omega-3 Index (average = 4.6%):

  • Both systolic and diastolic blood pressure were decreased
  • Blood pressure measurements decreased linearly with increasing Omega-3 Index.

The authors concluded: “A higher Omega-3 Index is associated with statistically significant, clinically relevant, lower systolic and diastolic blood pressure in normotensive, young and healthy individuals. Diets rich omega-3 fatty acids may be a strategy for primary prevention of hypertension.”

Let me translate that last sentence into plain English for you. The authors were saying that optimizing omega-3 intake in young adults may slow the age-related increase in blood pressure and reduce the risk of them developing high blood pressure as they age. This may begin to answer the question “Do omega-3s lower blood pressure in young, healthy adults?”

Or even more simply put: Aging is inevitable. Becoming unhealthy is not.

For more details, read the article above.

 

These statements have not been evaluated by the Food and Drug Administration. This information is not intended to diagnose, treat, cure or prevent any disease.

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