Vitamin K And Heart Disease Deaths

Written by Dr. Steve Chaney on . Posted in Heart Disease, Vitamin K

Does Vitamin K Reduce Heart Disease Risk?

Author: Dr. Stephen Chaney

 

viatmin k and heart diseaseYou are trying to live a heart healthy lifestyle, but it is so confusing. It seems like there are new heart healthy diets, foods, and nutrients each week. How can you possibly keep up?

Some of those “heart healthy” recommendations contradict each other. They can’t all be true. Which should you believe? I will answer that question in my new books “Slaying the Food Myths” and “Slaying the Supplement Myths.

Today, however, I am going to add to your confusion by adding another nutrient, vitamin K, to your “heart healthy” list. When it comes to heart health, vitamin K is a neglected nutrient. Most people think it is just needed for blood clotting. It doesn’t have the recognition and glamor of omega-3s, antioxidants, and polyphenols for heart health. However, recent research suggests it may play a crucial role in protecting your heart. So, I will explain how vitamin K and heart disease are related.

Before, I go into today’s study, let me give you some background information on vitamin K metabolism and heart health.

Metabolism 101: Vitamin K and Heart Disease

viatmin k and heart disease vegetablesVitamin K is a coenzyme for enzymes that add carboxyl groups to proteins. Without going into a lot of boring detail, carboxylated proteins:

  • Are more water soluble. That makes them more efficient at catalyzing metabolic reactions in our cells.
  • Chelate calcium. That allows them to catalyze calcium-dependent reactions.

For this discussion there are 3 kinds of calcium-dependent reactions catalyzed by carboxylated proteins that are important to know:

  • Reactions involved in blood clotting. Hence, vitamin K is essential for blood clotting.
  • Reactions involved in depositing calcium in our bones. Hence, vitamin K is essential for bone formation.
  • Reactions involved in removing calcium deposits from soft tissues. Hence, vitamin K is essential for keeping our arteries clear of calcium deposits.

If you think about those last two reactions, vitamin K deficiency is the worst of all possible worlds. Calcium in our bloodstream is less likely to be deposited in our bones and more likely to be deposited in our arteries. Vitamin K deficiency is bad for bone health and bad for heart health.

There is only one other factoid you need to know to understand the study I will discuss below. Because vitamin K is essential for the carboxylation of certain proteins, the uncarboxylated level of those proteins in the bloodstream can be used as an indirect assay for vitamin K deficiency. That is the assay that was used in this study.

How Was The Study Performed?

viatmin k and heart disease deathsIn this study (I.J. Riphagen et al, Nutrients, 9, 1334; doi: 10.3390/nu9121334, 2017 ) the investigators studied 4275 subjects enrolled in a clinical trial called PREVEND (Prevention of Renal and Vascular End-Stage Disease). The study population was recruited from the city of Groningen in the Netherlands.

In terms of study population characteristics, the average age was 53, the population was 46% male, 94% Caucasian, and 60% of the population already had renal disease at the time of enrollment (The significance of this will be discussed later).

Study participants were followed for 10 years. By then 279 had died, with 74 deaths attributable to heart disease. Here are the results of the study:

  • 30% of the population was vitamin K deficient.
  • Vitamin K deficiency was close to 50% for the elderly and for subjects with hypertension, diabetes, kidney disease, and cardiovascular disease.
  • Vitamin K deficiency was significantly correlated with all-cause mortality and cardiovascular mortality.

The authors concluded: “Importantly, a low vitamin K status is not only a clinically relevant risk factor for adverse health outcomes, but it may be a modifiable risk factor. Given the availability of vitamin K supplements, vitamin K insufficiency seems an attractive target for preventative intervention. Future prospective clinical trials are needed to investigate whether correction of low vitamin K status can indeed improve health outcomes.”

Pros and Cons of This Study

Cons:

  • This is an association study. It showed that vitamin K deficiency was associated with cardiovascular mortality, but it didn’t show that vitamin K deficiency caused cardiovascular mortality.
  • Kidney disease reduces the efficiency of vitamin K-dependent carboxylation of proteins. This study relied on levels of uncarboxylated protein for determining vitamin K status, and 60% of the subjects had kidney disease. The study might have overestimated the prevalence of vitamin K deficiency.
  • The population of the study were primarily Caucasian from one city in the Netherlands. It is not clear whether these findings would be equally true for other population groups.

Pros:

  • This study is consistent with previous studies. Several other studies have reported a correlation between vitamin K deficiency and either arterial calcification or heart disease risk. At least one study has shown that vitamin K supplementation can reverse arterial calcification.
  • The levels of vitamin K deficiency seen in this study are consistent with previous studies that have measured blood levels of vitamin K directly.

 

Vitamin K1 Versus K2: What Happens Naturally?

 

viatmin k and heart disease vitamin k1 and vitamin k2There are two forms of vitamin K, vitamin K1 and vitamin K2. Vitamin K1 is used for the blood clotting reactions. Vitamin K2 is used for the reactions involving bone formation and removal of calcium from soft tissues. That has led to a vigorous debate about whether vitamin K1 or K2 supplements are better. I won’t get into that debate, because the data aren’t conclusive yet. However, I will point out that there is a natural relationship between vitamin K1 and K2 that has existed for thousands of years.

Vitamin K1 is the primary dietary form of vitamin K. It is found in heart-healthy foods like green leafy vegetables; cruciferous vegetables like broccoli, Brussels sprouts and cabbage; and other healthy foods like carrots, blueberries, and asparagus. It is converted to vitamin K2 by our intestinal bacteria. Small amounts of vitamin K2 can also be found in less heart-healthy foods like cheeses, egg yolks, butter, chicken liver, and salami.

Simply put, if we eat healthy foods and have healthy gut bacteria, we get vitamin K1 from our diet, and our gut bacteria make all the vitamin K2 we need. This is a system that has worked well for humankind since the dawn of time. It’s only when we start messing up our diet and our gut bacteria that we need to start arguing about whether vitamin K1 or K2 supplements are better. It’s not nice to mess with Mother Nature.

 

The Bottom Line

 

A recent study in the Netherlands found that:

  • 30% of the population was vitamin K deficient.
  • Vitamin K deficiency was close to 50% for the elderly and for subjects with hypertension, diabetes, kidney disease, and cardiovascular disease.
  • Vitamin K deficiency was significantly correlated with all-cause mortality and cardiovascular mortality.

The authors concluded: “…a low vitamin K status is not only a clinically relevant risk factor for adverse health outcomes, but it may be a modifiable risk factor. Given the availability of vitamin K supplements, vitamin K insufficiency seems an attractive target for preventative intervention.”

For more details about vitamin K and heart disease and a brief discussion of vitamin K1 and vitamin K2, 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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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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