Do Omega-3s Lower Blood Pressure?

Written by Dr. Steve Chaney on . Posted in Food and Health, Issues, Supplements and Health

The Good News About Fish Oil

Author: Dr. Stephen Chaney

High Blood PressureHigh blood pressure or hypertension is a major problem in this country. Over 60% of Americans have high blood pressure. Only 47% of those with hypertension are adequately controlled. 20% of them don’t even know that they have high blood pressure.

In this case, ignorance is definitely not bliss. That’s because high blood pressure significantly increases the risk of stroke, heart attacks and congestive heart failure.

The causes of high blood pressure are many. Genetics, obesity, lack of exercise, sodium, alcohol, saturated fats and too few fresh fruits and vegetables all play a role. Age also plays a role. As we age, our blood vessels become less flexible and our blood pressure rises by about 0.6 mm Hg per year.

Medications can help, but many of them have significant side effects and often aren’t fully effective in controlling blood pressure. That’s why natural approaches are so important.

Because there are so many causes of hypertension, natural approaches for lowering your blood pressure are not simple. Natural approaches start with weight loss, restricting sodium intake, increasing physical activity, moderating alcohol intake and something called the DASH diet. In short, there is not just one simple change that you can make that will totally eliminate hypertension. It requires a complete lifestyle change.

That’s why the latest study on the effect of omega-3s on blood pressure is so exciting. If the headlines are true, adding omega-3s to your diet may be one of the most effective things you can do to lower your blood pressure naturally. So let’s examine the study to see if the headlines are accurate.

How Was The Study Designed?

This study (Miller et al, American Journal of Hypertension, doi:10.1093/ajh/hpu024) was a very large, well designed study. It is a meta-analysis of 70 randomized, placebo controlled clinical studies. Key characteristics of these studies were:

  • The mean study duration was 69 days. That means these beneficial effects occur relatively quickly.
  • The mean EPA + DHA dose was 3.8 g/day (range = 0.2 – 15 g/day). A wide range of doses was included.
  • The EPA & DHA came from all sources (seafood, EPA+DHA fortified foods, fish oil, algal oil, and purified ethyl esters. The source did not affect the outcome.
  • Olive oil was the most commonly used placebo, with omega-6 vegetable oils being used as placebos in a few studies. The choice of placebo did not affect the outcome.
  • None of the people in these studies were taking blood pressure lowering medications. That means these studies were specifically designed to see whether omega-3s lowered blood pressure, not whether they had any additional benefit for people already taking medications. This is important because if you only focus on groups who are already taking multiple medications, you tend to obscure the beneficial effects of omega-3s (see my recent Health Tip “Is Fish Oil Really Snake Oil?”)

Do Omega-3s lower Blood Pressure?

Fish OilThe authors of the study reported that:

  • Compared to placebo, EPA+DHA reduced systolic blood pressure (that’s the upper reading) by 1.52 mm Hg and diastolic blood pressure (that’s the lower reading) by 0.99 mm Hg.
  • When they looked at those participants who already had high blood pressure, the numbers were even more impressive – a 4.51 mm Hg decrease in systolic blood pressure and a 3.05 mm Hg decrease in diastolic blood pressure. That’s important because for each 2 mm Hg reduction in blood pressure there is a 6% decrease in stroke mortality, a 4% decrease in heart disease mortality, and a 3% decrease in total mortality.

More to the point, the authors of the study concluded that “A decrease of 4.51 mm Hg in systolic blood pressure among those with high blood pressure could help an individual avoid having to take medication to control blood pressure levels”.

  • When they looked at the study participants who had normal blood pressure the numbers were still significant – a 1.25 mm Hg decrease in systolic blood pressure and a 0.62 decrease in diastolic blood pressure. The authors pointed out that this could prevent, or at least delay, the age-related progression towards hypertension.
  • The effect of omega-3s on systolic blood pressure (4.51 mm Hg decrease) was comparable to the most successful lifestyle interventions – 3-10 mm Hg decrease for 10 pound weight loss, 4-9 mm Hg decrease for increased physical activity, 2-8 mm Hg decrease for sodium restriction, and 2-4 mm Hg for decreased alcohol consumption.
  • A dose of at least 1 gm/day of EPA+DHA was required for a significant decrease in systolic blood pressure, and a dose of over 2 gm/day was required for a significant decrease in both systolic and diastolic blood pressure

While this is a single study, it is consistent with a number of previous studies in this area. Based on the existing body of literature I would recommend omega-3s as part of a holistic approach for keeping your blood pressure under control.

The Bottom Line:

1)     A recent meta-analysis of 70 published clinical studies (AJH, doi: 10.1093/ajh/hpu024) has shown fairly convincingly that omega-3 fatty acids are effective at lowering blood pressure. Moreover, this study is consistent with a number of previous studies. The evidence appears to be strong enough for omega-3s to be considered as part of a holistic approach to keeping your blood pressure under control.

2)     If you already have high blood pressure, you should know that omega-3s caused blood pressure to decrease by 4.51 mm Hg in people like you. The authors of the study concluded that this decrease in blood pressure is large enough that some people may be able to avoid blood pressure medicines entirely. For others addition of omega-3s to their diet will likely allow their physicians to reduce the dose of medications required to keep their blood pressure under control – thus minimizing the side effects of the medications.

3)     If you already have slightly elevated blood pressure that has not yet progressed to clinical hypertension, you should know that omega-3s also give a modest decrease in blood pressure in people like you. The authors of the study concluded that this decrease was enough to prevent or delay the age-related onset of hypertension.

4)     The effect of omega-3s on reducing blood pressure is equivalent to the most successful lifestyle changes (weight loss, increased physical activity, sodium restriction and alcohol moderation). That doesn’t mean that you should pop fish oil pills and forget the other lifestyle changes. The idea is to combine as many of those lifestyle changes as possible so that you may never have to worry about high blood pressure again.

5)     You need at least 1 gm/day of EPA+DHA to reduce systolic blood pressure and more than 2 gm/day to reduce both systolic and diastolic blood pressure.

6)     Contrary to the hype you may have been reading elsewhere, the source of EPA+DHA didn’t matter. The only caveat is that many people really struggle with trying to get 1-2 gm/day of EPA+DHA from fish. It’s a bit too much of a good thing.

7)     Don’t think of hypertension as a “Do it yourself” project. Hypertension is a silent killer. It’s one of those diseases where the first symptom is often sudden death – or, even worse, a life that is no longer worth living. Work with your physician. Let them help you find the right balance between lifestyle changes (including omega-3s) and medications to keep your blood pressure under control.

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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Best Diet For Heart Disease Prevention

Posted July 9, 2019 by Dr. Steve Chaney

Are The American Heart Association’s Recommendations Correct?

Author: Dr. Stephen Chaney

 

What is the best diet for heart disease prevention? 

diet for heart disease preventionHeart disease is a killer. It continues to be the leading cause of death – both worldwide and in industrialized countries like the United States and the European Union. When we look at heart disease trends, it is a good news – bad news situation.

  • The good news is that heart disease deaths are continuing to decline in adults over 70.
  • The decline among senior citizens is attributed to improved treatment of heart disease and more seniors following heart-healthy diets.
  • The bad news is that heart disease deaths are starting to increase in younger adults, something I reported in an earlier issue, Heart Attacks Increasing in Young Women of “Health Tips From the Professor.”
  • The reason for the rise in heart disease deaths in young people is less clear. However, the obesity epidemic, junk and convenience foods, and the popularity of fad diets all likely play a role.

Everyone has a magic diet for reducing heart disease risk. The American Heart Association tells us to avoid fats, especially saturated fats. Vegans tell us to avoid animal protein. Paleo and keto enthusiasts tell us carbs are the problem. Who is correct?

Of course, we don’t eat fats, carbohydrates, or proteins. We eat foods. That is why a recent study (T Meier et al, European Journal of Epidemiology, 34: 37-45, 2019) is so important. It reported which foods increase and which decrease the risk of premature heart disease deaths.

How Was The Study Done?

diet for heart disease prevention studyThe authors of the current study analyzed data from the “Global Burden of Diseases (GBD) Study”, a major world-wide effort designed to estimate the portions of deaths caused by various risk factors.

The current study focused on the impact of 12 dietary risk factors on heart disease deaths between 1990 and 2016 for 51 countries in four regions (Western Europe, Central Europe, Eastern Europe, and Central Asia).

The dietary risk factors were:

  • Diets low in fiber, fruits, vegetables, legumes, nuts and seeds, polyunsaturated fatty acids, omega-3 fatty acids, and whole grains.
  • Diets high in sodium, processed meats, sugar-sweetened beverages, and trans fatty acids.

Saturated fat and meat were not explicitly included in the GBS Study data. However, diets low in polyunsaturated fats and omega-3 fats are likely high in saturated fats. Similarly, diets low in fruits, vegetables, whole grains, and legumes are likely higher in meats. The study also did not include dairy, and some recent studies suggest that some dairy foods may decrease heart disease risk.

For simplicity I will only consider the findings from Western Europe because their diet and heart disease death trends are similar to those in the United States.

 

Best Diet for Heart Disease Prevention?

plant-based diet bestThe study found that in 2016 (the last year for which data were available):

  • Dietary risk factors were responsible for 49.2% of heart disease deaths.
  • 6% of all diet-related heart disease deaths occurred in adults younger than 70, and that percentage has been increasing in recent years.

When they looked at the contribution of individual foods to diet related heart disease deaths, the percentages were:

  • Diets low in whole grains = 20.4%
  • Diets low in nuts and seeds = 16.2%
  • Diets low in fruits = 12.5%
  • Diets high in sodium = 12.0%
  • Diets low in omega-3s = 10.8%
  • strong heartDiets low in vegetables = 9.0%
  • Diets low in legumes = 7.0%
  • Diets low in fiber = 5.7%
  • Diets low in polyunsaturated fats = 3.7%
  • Diets high in processed meats = 1.6%
  • Diets high in trans fatty acids = 0.8%
  • Diets high in sugar-sweetened beverages = 0.1%

So, what is the best diet for heart disease prevention?

In short, this study concluded:

  • A primarily plant-based diet is the best protection against premature death due to heart disease.
  • All plant-based food groups (whole grains, nuts and seeds, fruits, vegetables, and legumes) play an important role in reducing heart disease deaths.
  • Meat was not included in the analysis, but it is likely that most people’s diets in this region of the world contained some meat. The most likely take-away is that meat does not affect heart disease risk in the context of a primarily plant-based diet.
  • Dairy was not included in the analysis either, but some studies suggest dairy, particularly fermented dairy foods, reduce heart disease risk.
  • Finally, the study concluded: “Compared to other…modifiable risk factors (physical inactivity, drug and alcohol abuse, tobacco smoking, obesity, etc.), an altered diet is the most effective means of preventing premature deaths from cardiovascular disease in Western Europe.”

While every study has its weaknesses, this study is consistent with multiple previous studies showing that primarily plant-based diets are best for reducing heart disease risk. You will find a more complete discussion of these studies in my book “Slaying The Food Myths.”

 

Are the American Heart Association’s Recommendations Correct?

With this study’s results in mind we can now ask whether the recommendations of the American Heart Association and other popular diets are correct. Are they likely to reduce heart disease deaths?

  • The American Heart Association Recommends a dietary pattern that emphasizes a variety of fruits and vegetables, whole grains, nuts and legumes, skinless poultry and fish, and low-fat dairy products. This study supports those recommendations.
  • This study also supports the heart-health benefits of the Mediterranean and DASH diets.
  • Meat and dairy were not explicitly considered in this study. Thus, the results of this study are also consistent with vegan and semi-vegetarian diets.
  • However, low carb diets like Paleo and keto eliminate some of the key food groups (whole grains, fruits, and legumes) that appear to be essential for reducing heart disease risk. 40% of the heart-health benefits in this study came from those 3 food groups. Thus, this study does not support claims that those two diets are heart-healthy long term.

 

The Bottom Line

 

Everyone has a magic diet for reducing heart disease risk. The American Heart Association tells us to avoid fats, especially saturated fats. Vegans tell us to avoid animal protein. Paleo and keto enthusiasts tell us carbs are the problem. Who is correct?

A recent study provides some important clues. It looked at dietary patterns associated with reduced risk of premature death from heart disease in Western Europe. The study concluded:

  • A primarily plant-based diet is the best protection against premature death due to heart disease.
  • All plant-based food groups (whole grains, nuts and seeds, fruits, vegetables, and legumes) play an important role in reducing heart disease deaths.
  • Meat did not appear to affect heart disease risk in the context of a primarily plant-based diet.
  • Dairy was not included in the analysis, but some studies suggest dairy, particularly fermented dairy foods, reduce heart disease risk.
  • Finally, the study concluded: “Compared to other…modifiable risk factors (physical inactivity, drug and alcohol abuse, tobacco smoking, obesity, etc.), an altered diet is the most effective means of preventing premature deaths from cardiovascular disease.”

While every study has its weaknesses, this study is consistent with multiple previous studies showing that primarily plant-based diets are best for reducing heart disease risk. You will find a more complete discussion of these studies in my book “Slaying The Food Myths.”

With this study’s results in mind we can now ask whether the recommendations of the American Heart Association and other popular diets are correct. Are they likely to reduce heart disease deaths?

  • The American Heart Association Recommends a dietary pattern that emphasizes a variety of fruits and vegetables, whole grains, nuts and legumes, skinless poultry and fish, and low-fat dairy products. This study supports those recommendations.
  • This study also supports the heart-health benefits of the Mediterranean and DASH diets.
  • Meat and dairy were not explicitly considered in this study. Thus, the results of this study are also consistent with vegan and semi-vegetarian diets.
  • However, low carb diets like Paleo and keto eliminate some of the key food groups (whole grains, fruits, and legumes) that appear to be essential for reducing heart disease risk. 40% of the heart-health benefits in this study came from those 3 food groups. Thus, this study does not support claims that those two diets are heart-healthy long term.

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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