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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Latest Article

Does Protein Supplement Timing Matter?

Posted May 15, 2018 by Dr. Steve Chaney

How Do You Gain Muscle Mass & Lose Fat Mass?

Author: Dr. Stephen Chaney

 

protein supplement timingMost of what you read about protein supplements on the internet is wrong. That is because most published studies on protein supplements:

  • Are very small
  • Are not double blinded.
    • Both the subjects and the investigators knew who got the protein supplement.
  • Are done by individual companies with their product.
    • You have no idea which ingredients are in their product are responsible for the effects they report.
    • You have no idea how their product compares with other protein products.
    • There is no standardization with respect to the amount or type of protein or the addition of non-protein ingredients.

Because of these limitations there is a lot of misleading information on the benefits of protein supplements timing and maximal benefit. Let’s start by looking at why people use protein supplements. Let’s also look at what is generally accepted as true with respect to the best supplement timing.

There are 4 major reasons people consume protein supplements:

  • Enhance the muscle gain associated with resistance training: In this case, protein supplements are customarily consumed concurrently with the workout.
  • Preserve muscle and accelerate fat loss while on a weight loss diet: In this case, protein supplements are customarily consumed with meals or as meal replacements.
  • Provide a healthier protein source. In this case, protein supplements are customarily consumed with meals in place of meat protein.
  • Prevent muscle loss associated with aging or illness. There is no customary pattern associated with this use of protein supplements.

How good are the data supporting the customary timing of protein supplementation? The answer is: Not very good. The timing is based on a collection of weak studies which do not always agree with each other.

The current study  (J.L. Hudson et al, Nutrition Reviews, 76: 461-468, 2018 ) was designed to fill this void in our knowledge. It is a meta-analysis that compares all reasonably good studies that have looked at the effect of protein supplement timing on weight gain or loss, lean muscle mass gain, fat loss, and the ratio of lean muscle mass to fat mass.

How Was The Study Done?

The authors started by doing a literature search of all studies that met the following criteria:

  • The study was a randomized control trial with parallel design. This means that study contained a control group. It does not mean that the investigators or subjects were blinded with respect to which subjects used a protein supplement and which did not.
  • The subjects were engaged in resistance training.
  • The study lasted 6 weeks or longer.
  • Reliable methods were used to measure body composition (lean muscle mass and fat mass).
  • The subjects were healthy and at least 19 years old.
  • There was no restriction on the food the subjects consumed.

The authors started with 2074 published studies and ended up with 34 that met all their criteria. They then separated the studies into two groups – those in which the protein supplements were used with meals and those in which the protein supplements were used between meals.

Both groups were diverse.

  • Group 1 included subjects who consumed their protein supplement with their meal and those who consumed their protein supplement as a meal replacement.
  • Group 2 included subjects who consumed their protein supplement concurrent with exercise (usually immediately after exercise) and those who consumed their protein supplement at a fixed time of day not associated with exercise.

Does Protein Supplement Timing Matter?

 

protein supplement timing workoutsBecause the individual studies were very diverse in the way they were designed, the authors could not calculate a reliable estimate of how much lean muscle mass was increased or fat mass was decreased. Instead, they calculated the percentage of studies showing an increase in lean muscle mass or a decrease in fat mass.

When the authors compared protein supplements consumed with meals versus protein supplements consumed between meals:

  • Weight gain was observed in 56% of the studies of protein supplementation with meals compared to 72% of the studies of protein supplementation between meals. In other words, protein supplements consumed with meals were less likely to lead to weight gain than protein supplements consumed between meals.
  • An increase in lean muscle mass was observed in 94% of the studies of protein supplementation with meals compared to 90% of the studies of protein supplementation between meals. In other words, timing of protein supplementation did not matter with respect to increase in muscle mass.
  • A loss of fat mass was observed in 87% of the studies of protein supplementation with meals compared to 59% of the studies of protein supplementation between meals. In other words, protein supplements consumed with meals were more likely to lead to loss of fat mass.
  • An increase in the ratio of lean muscle mass to fat mass was observed in 100% of the studies of protein supplementation with meals compared to 87% of the studies of protein supplementation between meals. In short, protein supplements consumed with meals were slightly more likely to lead to an increase in the ratio of lean muscle mass to fat mass.

The following seem to suggest protein supplement timing matters:

The authors pointed out that their findings were consistent with previous studies showing that when protein supplements are consumed with a meal they displace some of the calories that otherwise would have been consumed. Simply put, people naturally compensate by eating less of other foods.

In contrast, the authors stated that previous studies have shown that when foods, especially liquid foods, are consumed as snacks (between meals), people are less likely to compensate by reducing the calories consumed in the next meal.

The others concluded: “Concurrently with resistance training, consuming protein supplements with meals, rather than between meals, may more effectively promote weight control and reduce fat mass without influencing improvements in lean [muscle] mass.”

What Are The Limitations Of The Study?

Meta-analyses such as this one, are only as good as the studies included in the meta-analysis. Unfortunately, most sports nutrition studies are very weak studies. Thus, this meta-analysis is a perfect example of the “Garbage In: Garbage Out (GI:GO)” phenomenon.

For example, let’s start by looking at what the term “protein supplement” meant.

  • Because the studies were done by individual companies with their product, the protein supplements in this meta-analysis:
    • Included whey, casein, soy, bovine colostrum, rice or combinations of protein sources.
    • Were isolates, concentrates, or hydrolysates.
    • Contained various additions like creatine, amino acids, and carbohydrate.
  • As I discuss in my book, Slaying the Food Myths, previous studies have shown that optimal protein and leucine levels are needed to maximize the increase in muscle mass and decrease in fat mass associated with resistance exercise. However, neither protein nor leucine levels were standardized in the protein supplements included in this meta-analysis.
  • Previous studies have shown that protein supplements that have little effect on blood sugar levels (have a low glycemic index) are more likely to curb appetite. However, glycemic index was not standardized for the protein supplements included in this meta-analysis.

protein supplement timing workout peopleIn short, the conclusions of this study might be true for some protein supplements, but not for others. We have no way of knowing.

We also need to consider the composition of the two groups.

  • Protein supplements used as meal replacements are more likely to decrease weight and fat mass than protein supplements consumed with meals. Yet, both were included in group 1.
  • Some studies suggest that protein supplements consumed concurrent with resistance exercise are more likely to increase muscle mass than protein supplements consumed another time of day. Yet, both are included in group 2. We also have no idea whether the meals with protein supplements in group 1 were consumed shortly after exercise or at an entirely different time of day.

This was the most glaring weakness of the study because it was completely avoidable. The authors could have grouped the studies into categories that made more sense.

In other words, there are multiple weaknesses that limit the predictive power of this study.

What Can We Learn From This Study?

Despite its many limitations, this study does remind us that protein supplements do have calories. This is of relatively little importance for people whose primary goal is to increase lean muscle mass.

However, most of us are using protein supplements to lose weight or to increase our lean mass to fat mass ratio. Simply put, we are either trying to lean out (shape up) or lose weight. And, we want to lose that weight primarily by getting rid of excess fat. For us, calories do matter. With that in mind:

  • If we are consuming a protein supplement immediately after exercise or between meals we probably should make a conscious effort to reduce our daily caloric intake elsewhere in our diet.
  • Alternatively, we could consume the protein supplement with a meal, but time the meal so it occurs shortly after exercise.

 

The Bottom Line:

 

A recent study looked at the optimal timing of protein supplements consumed by subjects who were engaged in resistance exercise. Specifically, the study compared protein supplements consumed with meals versus protein supplements consumed between meals on weight, lean muscle mass, fat mass, and the ratio of lean muscle mass to fat mass. The study reported:

  • Protein supplements consumed with meals were less likely to lead to weight gain than protein supplements consumed between meals.
  • Timing of protein supplementation did not matter with respect to increase in muscle mass.
  • Protein supplements consumed with meals were more likely to lead to loss of fat mass.
  • Protein supplements consumed with meals were slightly more likely to lead to an increase in the ratio of lean mass to fat mass.

The authors pointed out that their findings were consistent with previous studies showing that when a protein supplement was consumed with a meal it displaces some of the calories that would have been otherwise consumed. Simply put, people naturally compensate by eating less of other foods.

In contrast, the authors said that previous studies have shown that when foods, especially liquid foods, are consumed as snacks (between meals), people are less likely to compensate by reducing the calories consumed in the next meal.

As discussed in the article above, the study has major weaknesses. However, despite its many weaknesses, this study does remind us that protein supplements do have calories. This is of relatively little importance for people whose primary goal is to increase lean muscle mass.

However, for those of us who are using protein supplements to lose weight or to increase our lean mass to fat mass ratio, calories do matter.  With that in mind:

  • If we are consuming a protein supplement immediately after exercise or between meals we probably should make a conscious effort to reduce our daily caloric intake elsewhere in our diet.
  • Alternatively, we could consume the protein supplement with a meal, but time the meal so it occurs shortly after exercise.

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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