Vitamin K Archives - Health Tips From The Professor

Are Omega-3s Needed For Strong Bones?

September 16, 2025 by Dr. Steve Chaney

Why Are Omega-3s Needed For Strong Bones?

Author: Dr. Stephen Chaney

Osteoporosis is one of the dreaded diseases associated with aging.

Over 50% of women and 25% of men will develop osteoporosis in their lifetime.

And the risk of osteoporosis is highest for Caucasians.

Over 40% of white women and 13% of white men will develop an osteoporotic fracture in their lifetime.

And osteoporotic fractures can be deadly. Bone fractures increase the risk of death 3-5-fold within the next few months. Moreover, the quality of life is diminished, and the risk of death is elevated for years after the fracture occurs.

So, if you are like many people, you are doing all you can to keep your bones strong so you will minimize your chances of developing osteoporosis. You probably even have a check list:

Resistance exercise (strengthens the bones you pull on)……Check

Walking (strengthens hip and leg bones)………………………Check

Adequate calcium & vitamin D (essential for strong bones)…Check

Magnesium & vitamin K (also important for strong bones)…..Check

Adequate protein (Muscle pulling on bone strengthens it)…..Check

Adequate omega-3s………………………………………………What!!!

You probably didn’t know about omega-3s. But recent research suggests they may also play a role in building strong bones and preventing osteoporosis. For example, studies show that omega-3s may influence bone metabolism by:

Enhancing absorption of calcium from the intestine.

Reducing the rate at which bone is broken down.

Increasing the rate at which new bone is built.

But large-scale population studies showing that omega-3 intake influences the risk of developing osteoporosis are lacking. The study ( Z Liu et al, Frontiers In Nutrition, 11: 1467559, 2023) I am discussing today was designed to fill that gap.

But before I describe the study, I should give you a quick review of bone metabolism.

Biochemistry 101: Bone Metabolism

To truly understand osteoporosis and how to prevent it, you need to know a bit about bone metabolism. We tend to think of our bones as solid and unchanging, much like the steel girders supporting an office building. Nothing could be further from the truth. Our bones are dynamic organs that are in constant change throughout our lives.

Cells called osteoclasts constantly break down old bone (a process called resorption), and cells called osteoblasts replace it with new bone (a process called accretion). Without this constant renewal process our bones would quickly become old and brittle.

In short, our bones are not inert. They are in constant flux. If we exercise regularly and get enough calcium, vitamin D, magnesium, and vitamin K from our diet, bone metabolism looks like this as we age.

When we are young, osteoblast activity predominates, so accretion (the bone building process) exceeds bone resorption, and our bones grow in size and density.

When we are adults, osteoblast and osteoclast activity are in balance. Thus, bone accretion and resorption are in balance, and our bone density stays constant. The top portion of the picture above depicts what happens when osteoclast and osteoblast activity are in balance.

However, as we age osteoclast activity predominates, and we start to lose bone density. Eventually our bones look like Swiss cheese and break very easily. This is called osteoporosis. The bottom portion of the picture depicts this.

We should also think of our bones as calcium reservoirs. We need calcium in our bloodstream 24 hours a day for our muscles, brain, and nerves to function properly, but we only get calcium in our diet at discrete intervals. Consequently:

When we eat our body tries to store as much calcium as possible in our bones.

Between meals, we break down bone material so that we can release the calcium into our bloodstream that our muscle, brain & nerves need to function.

If we lead a “bone healthy” lifestyle, all of this works perfectly. We build strong bones during our growing years, maintain healthy bones during our adult years, and only lose bone density slowly as we age – maybe never experiencing osteoporosis. We always accumulate enough calcium in our bones during meals to provide for the rest of our body between meals.

I should note that this is the current paradigm for bone metabolism. The study I am discussing today is asking whether omega-3 fatty acids should also be considered as part of a bone-healthy lifestyle.

How Was This Study Done?

The investigators used data from NHANES (National Health And Nutrition Examination Survey), an ongoing study to assess the health and nutritional status of adults and children in the United States. Specifically, this study combined data from participants from the 2005-2010, 2013-2014, and 2017-2018 NHANES surveys.

The participants included in the survey:

Were greater than 50 years old.

Had completed two 24-hour dietary recall surveys to determine the omega-3 content of their diet (The average omega-3 intake of the two surveys was used for this study).

Had a bone mineral density (BMD) test performed using dual-energy X-ray absorptiometry (DXA) scans.

Participants were excluded from the study if they had incomplete diet or bone mineral density data or if they had a disease that affects bone metabolism.

A total of 8,889 participants were included in the study. They were divided into 3 categories based on their bone density:

Normal bone density (4,421 participants)
Osteopenia (3,952 participants)
Osteoporosis (516 participants)

Finally, the participants were divided into quartiles based on their omega-3 intake, and omega-3 intake was correlated with bone density.

Are Omega-3s Needed For Strong Bones?

The study results were as follows:

Omega-3 intake was inversely related to bone density. Simply put, that means:

- The highest intake of omega-3s was observed in the group with normal bone density, and…

- The lowest omega-3 intake was observed in the osteoporosis group.

When the participants were divided into quartiles based on their omega-3 intake:

Participants with the highest omega-3 intake were 29% less likely to develop osteoporosis than participants with the lowest omega-3 intake.

When the investigators looked at subgroups, they found stronger effects of omega-3s on osteoporosis risk for women, people under 60, and non-smokers. Specifically:

Women with the highest omega-3 intake were 35% less likely to develop osteoporosis.

People under 60 were 49% less likely to develop osteoporosis.

Non-smokers were 36% less likely to develop osteoporosis.

The investigators concluded, “This study demonstrates a significant inverse relationship between dietary omega-3 fatty acid intake and osteoporosis risk, suggesting omega-3s play a crucial role in bone health. However, further longitudinal studies are needed to confirm these studies and refine dietary recommendations for osteoporosis prevention.”

Why Are Omega-3s Needed For Strong Bones?

You are probably thinking,

“Calcium and magnesium are part of bone structure. Vitamin D and vitamin K facilitate the incorporation of calcium into bone. So, it is logical that these nutrients would be important for strong bones.”

“But what role do omega-3s play? They aren’t incorporated into bone, and they don’t affect calcium metabolism.”

Here is what the authors said about that:

Omega-3s are anti-inflammatory. They decrease production of the pro-inflammatory cytokines that stimulate osteoclasts – the cells that break down bone.

EPA and DHA are also converted to prostaglandins that stimulate osteoblasts – the cells that build new bone.

Finally, the authors said, “Omega-3 fatty acids, especially EPA and DHA, have been shown to enhance calcium absorption in the gut – a process crucial for maintaining optimal bone mineral density…Omega-3s …do this by altering the lipid composition of cell membranes, thereby affecting calcium channels and enhancing calcium availability for bone tissue.”

Let me help you understand that statement.

While we might think of our cell membranes as rigid structures, they are quite fluid. The closest analogy I can think of is a large lake. You may not see any waves or ripples, but if a leaf drops on the surface it doesn’t stay in one place. It moves. We can think of calcium channels in our membrane like leaves on the water. They move across the cell membrane.

How fast they move depends on the fluidity of the cell membrane. This is determined by the lipids (fats) in the cell membrane, which in turn is determined by the fats in our diet. This is the one case where it is literally true that we are what we eat.

- When we have lots of saturated fats in our cell membranes, fluidity is low, and calcium channels move slowly across the membrane.

- When we have omega-3 fats in our cell membrane, fluidity is high, and calcium channels move quickly across the cell membrane.

Calcium channels work best when they cluster together, and this works best with highly fluid, omega-3-rich cell membranes.

What Does This Mean For You?

This study strongly suggests that omega-3s play a role in bone health, and they may be important for reducing our risk of osteoporosis. The authors concluded, “The findings suggest that omega-3 fatty acids play a critical role in bone health, supporting the need for dietary recommendations that encourage omega-3 consumption as a preventative measure against osteoporosis.”

However, this is the first study of its kind, which is why the authors said, “Further longitudinal studies are needed to confirm these findings.”

However, my biggest concern with the study is that it did not include information on the intake of the other nutrients essential for bone health (calcium, vitamin D, magnesium, and vitamin K). We don’t know at present the importance of omega-3s for preventing osteoporosis relative to dietary intake of other bone-healthy nutrients. For example:

Are omega-3s important for bone health when intake of calcium and/or the other bone-healthy nutrients are low?

Or are omega-3s equally important for bone health under all conditions?

However, the good news is that omega-3s have many proven health benefits such as heart health, controlling blood pressure, and reducing inflammation. If they are also important for bone health, we can consider it an unexpected benefit.

With that in mind, there are two important takeaways for you:

Omega-3s were most effective at preventing osteoporosis in people under 60. That is entirely consistent with what we know about preventing osteoporosis. The best prevention strategy is to build strong bones while you are young and maintain strong bones as long as possible in your adult years.

The optimal reduction of osteoporosis risk in this study was seen with an omega-3 intake of 1.86 g/d. While more studies are needed to define the optimal dose of omega-3s for reducing osteoporosis risk, this dose is within the “sweet spot” for the other omega-3 benefits I mentioned.

The Bottom Line

A recent study asked whether omega-3 fatty acids reduce the risk of osteoporosis.

The study found:

Omega-3 intake was inversely related to bone density.

When the participants were divided into quartiles based on their omega-3 intake:

Participants with the highest omega-3 intake were 29% less likely to develop osteoporosis than participants with the lowest omega-3 intake.

When the investigators looked at subgroups, they found stronger effects of omega-3s on osteoporosis risk for women, people under 60, and non-smokers.

The investigators concluded, “This study demonstrates a significant inverse relationship between dietary omega-3 fatty acid intake and osteoporosis risk, suggesting omega-3s play a crucial role in bone health. This supports the need for dietary recommendations that encourage omega-3 consumption as a preventative measure against osteoporosis.”

For more information on this study, why omega-3s reduce osteoporosis risk, and what this study means for you, 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.

_____________________________________________________________________________

My posts and “Health Tips From the Professor” articles carefully avoid claims about any brand of supplement or manufacturer of supplements. However, I am often asked by representatives of supplement companies if they can share them with their customers.

My answer is, “Yes, as long as you share only the article without any additions or alterations. In particular, you should avoid adding any mention of your company or your company’s products. If you were to do that, you could be making what the FTC and FDA consider a “misleading health claim” that could result in legal action against you and the company you represent.

For more detail about FTC regulations for health claims, see this link.

https://www.ftc.gov/business-guidance/resources/health-products-compliance-guidance

______________________________________________________________________

About The Author

Dr. Chaney has a BS in Chemistry from Duke University and a PhD in Biochemistry from UCLA. He is Professor Emeritus from the University of North Carolina where he taught biochemistry and nutrition to medical and dental students for 40 years. Dr. Chaney won numerous teaching awards at UNC, including the Academy of Educators “Excellence in Teaching Lifetime Achievement Award”. Dr Chaney also ran an active cancer research program at UNC and published over 100 scientific articles and reviews in peer-reviewed scientific journals. In addition, he authored two chapters on nutrition in one of the leading Biochemistry textbooks for medical students.

Since retiring from the University of North Carolina, he has been writing a weekly health blog called “Health Tips From the Professor”. He has also written two best-selling books, “Slaying the Food Myths” and “Slaying the Supplement Myths”. And most recently he has created an online lifestyle change course, “Create Your Personal Health Zone”. For more information visit https://chaneyhealth.com.

For the past 53 years Dr. Chaney and his wife Suzanne have been helping people improve their health holistically through a combination of good diet, exercise, weight control and appropriate supplementation.

Prenatal Supplements Strike Out Again

May 9, 2023 by Dr. Steve Chaney

Is It Three Strikes And You Are Out?

Author: Dr. Stephen Chaney

If you are pregnant, you want the best for your unborn baby. Your doctor has recommended a prenatal supplement, but do the prenatal supplements on the market meet your needs? A few months ago, I shared two studies that concluded that most prenatal supplements on the market are woefully inadequate.

In fact, the authors said, “[Our] analysis found that prenatal supplements vary widely in content, often only contain a subset of essential vitamins, and the levels were often below…recommendations.”

In other words, their study found that most prenatal vitamins on the market may not be adequate to support your needs and the needs of your child through pregnancy and breastfeeding.

Now, a third study on the topic has been published (KA Saunders et al, American Journal of Clinical Nutrition, 117: 823-829, 2023. It differs from the previous studies in that:

1) The previous two studies took a comprehensive approach, while this study focused on 6 key nutrients.

The previous studies included all nutrients important for a healthy pregnancy including choline, iodine, and vitamin K, which have only recently been shown to be important for a healthy pregnancy.

This study focused on 6 nutrients, vitamin A, vitamin D, folic acid, calcium, iron, and omega-3 fatty acids, which have long been recognized as essential for a healthy pregnancy.

2) The previous two studies focused on prenatal supplements, while this study focused on all supplements that might be taken by pregnant women.

3) The previous two studies asked whether supplements provided recommended amounts of all nutrients needed for a healthy pregnancy. This study took a “Goldilocks approach” and asked whether levels of these 6 essential nutrients were appropriate (“just right”). The study:

Started by determining the intake of these 6 key nutrients by American women. The authors of the study then added the amount of each nutrient provided by the supplements in their study to the amount of that nutrient in the diet of American women and:

- Calculated the minimum amount of each nutrient that would be needed to assure that 90% of American women taking a particular supplement would meet the recommended intake for pregnant and lactating women.

- Calculated the maximum amount of each nutrient provided by supplements in their study to assure that that 90% of American women taking that supplement would not get potentially toxic amounts of that nutrient.

In other words, for each of the 6 nutrients they calculated a supplemental dose range that was neither too low nor too high. They called this the “appropriate dose range” for each nutrient. Goldilocks would have called it “just right”.

I’m sure you are anxiously waiting to learn what their study found. But before we go there, I will describe how the study was done.

How Was The Study Done?

For the dietary intake portion of the study, the authors used dietary intake data previously collected from the Environmental Influences on Child Health Outcomes (ECHO) study.

The ECHO study is a consortium of 69 medical centers across multiple states. It is an observational study of mothers and their offspring designed to understand the effects of early life exposures on child health and development.

The current study analyzed dietary intake data for 2450 participants from 6 medical centers across 5 states in the ECHO study. The women in this study were diverse with respect to ethnicity, education, and weight.

All pregnant women in the current study completed at least one 24-hour dietary recall between 6-week gestation until delivery (24% completed one dietary recall. 76% completed two or more dietary recalls). Dietary intake was generally assessed with an expert interviewer and included all foods and beverages consumed in the previous 24 hours.

For the supplement portion of the study, the authors used the NIH Dietary Supplement Label Database because it is the most complete listing of supplements in the US. The authors selected 20,547 supplements that contained at least one of the 6 essential nutrients from this database.

To determine which of the 20,547 supplements contained appropriate levels of the 6 nutrients (vitamin A, vitamin D, folic acid, calcium, iron, and omega-3 fatty acids) selected for this study, the authors used the process described in the introduction above. Briefly:

The authors added the amount of each nutrient provided by the supplements in their study to the amount of that nutrient in the diet of American women and:

Calculated the minimum amount of each nutrient that would be needed to assure that 90% of American women taking a particular supplement would meet the recommended intake for pregnant and lactating women.

Calculated the maximum amount of each nutrient provided by supplements in their study to assure that that 90% of American women taking that supplement would not get potentially toxic amounts of that nutrient.

In other words, for each of the 6 nutrients they calculated a supplemental dose range that was neither too low nor too high. They called this the “appropriate dose range” for each nutrient.

Why Are The 6 Nutrients Included In This Study Important?

Dietary Intake Is Often Inadequate

The diet analysis of pregnant American women in this study found:

42% were at risk of inadequate vitamin A intake.

96% were at risk of inadequate vitamin D intake.

45% were at risk of inadequate folic acid intake.

55% were at risk of inadequate calcium intake.

93% were at risk of inadequate iron intake.

67% were at risk of inadequate omega-3 intake.

The percentage of women at risk for inadequate intake of these nutrients varied with age, ethnicity, and income levels. But the overall message is clear. Most American women are not getting enough of these essential nutrients from their diet alone.

The Risk of Inadequate and Excessive Intake Of These Nutrients

These 6 nutrients were chosen in part because reviews by the Cochrane Collaboration have concluded that inadequate intake of these nutrients are associated with complications during pregnancy and delivery. They can also adversely affect the health and normal development of the baby.

This is important because the Cochrane Collaboration is considered the Gold Standard of clinical studies. You can find a more detailed description of Cochrane Collaboration studies and why they are the Gold standard here.

[Note: The Cochrane Collaboration has not yet evaluated choline, iodine, and vitamin K for pregnant women, but their inclusion in prenatal supplements is supported by multiple clinical studies.]

In addition, excess intake of all these nutrients except omega-3s can harm both the fetus and the mother. The is why the Food and Nutrition Board has set ULs (Upper Limits – the level above which toxicity can occur) for 5 of the 6 nutrients. This is important because previous studies have suggested that up to 25% of women may be getting toxic levels of one or more of these nutrients when you consider both their dietary intake and their prenatal supplement.

Summary

In other words, both too little and too much of these nutrients can harm the mom and her baby. It is critical that prenatal supplements get the dosing right.

It is for that reason that the authors of this study have set an “appropriate dose range” (high enough that 90% of women have enough of each nutrient to prevent deficiency and low enough that 90% of women do not exceed the UL for each nutrient) as the standard for evaluating the adequacy and safety of supplements for pregnant women.

Prenatal Supplements Strike Out Again

Of the 20,547 supplements (421 labeled as prenatal supplements) available on the US market as of December 31, 2022, the investigators reported that:

Only 69 (0.3%) supplements contained all 6 nutrients considered essential for a healthy pregnancy.

Only 1 supplement contained all 6 nutrients at the appropriate doses, and it wasn’t even labeled as a prenatal supplement.

In addition:

One supplement containing all 6 nutrients put 100% of the women in their study at risk for excessive intake of folic acid.

Another supplement containing all 6 nutrients put 46% of the women in their study at risk of inadequate calcium intake.

The authors concluded, “Almost no US dietary supplements provide key nutrients in the doses needed for pregnant women. Affordable and convenient products that fill the gap between food-based intake and estimated requirements of pregnancy without inducing excess intake are needed to support pregnant women and their offspring.”

In short, the conclusion of this study can be summed up as, “Prenatal Supplements Strike Out Again”.

[Note: It sometime takes a while for supplement labels to be posted in the NIH Dietary Supplement Label Database. The authors acknowledged that this study may not include supplements introduced or reformulated in the last quarter of 2022.]

Is It Three Strikes And You Are Out?

If you are pregnant or thinking of becoming pregnant, this should be a wake-up call.

70% of pregnant women in this country take prenatal supplements, usually based on recommendations by their health care provider. They assume the prenatal supplements meet their needs and the needs of their unborn baby.

Yet three studies evaluating the adequacy of prenatal supplements have been published in the past few months. They took very different approaches in evaluating the supplements. But all three studies concluded that the vast majority of prenatal supplements on the market are woefully inadequate.

You may be wondering, “Is it three strikes, and you are out?” Are there no decent prenatal supplements on the market? The answer to those questions is, “No. There are good prenatal supplements on the market.”

You may be wondering how I can say that in the face of such overwhelming negative data. That’s because while all 3 studies were very good studies, they each had “blind spots”:

1) Each of the studies used very stringent criteria for identifying adequate prenatal supplements. In some cases, their criteria were stricter than the RDA recommendations and the recommendations of the American College of Obstetrics and Gynecology for pregnant and lactating women. It could be argued that their criteria were too stringent.

2) In the case of the current study, it could also be argued that evaluating only 6 nutrients is not a good criterion for evaluating the adequacy of prenatal supplements. For example, I looked up the one supplement rated as adequate in this study. It does provide appropriate doses of the 6 nutrients this study focused on. It also provides appropriate doses of vitamin K and iodine. But it does not provide choline. It is a very good supplement for women, but it is not the perfect prenatal supplement.

So, what can you do? How can you find the best prenatal supplement for you? Unfortunately, you cannot rely on advice from your friends or your health professional. You cannot rely on advertisements. That is a good place to start, but you have to do your own sleuthing.

With that in mind, I have listed 7 simple rules for selecting the best possible prenatal supplement in my article about the first two studies. Use these rules for evaluating every prenatal supplement you come across. Happy sleuthing.

The Bottom Line

A recent study evaluated all 20,547 supplements on the US market to see if they met the needs of pregnant women in this country.

They focused on 6 nutrients (vitamin A, vitamin D, folic acid, calcium, iron, and omega-3s) known to be essential for a healthy pregnancy.

They determined the dietary intake for all 6 nutrients in a cross section of pregnant women in the US.

They added the amount of the 6 nutrients in each of the 20,547 supplements to the dietary intake of those nutrients by pregnant women.

They then asked which supplements provided the “appropriate dose” of all 6 nutrients. They defined “appropriate dose” as the dose range that was.

- High enough to prevent deficiency of that nutrient in 90% of pregnant women taking the supplement…and…

- Low enough to prevent toxicity from that nutrient in 90% of pregnant women taking the supplement.

In other words, for each of the 6 nutrients they calculated a supplemental dose range that was neither too low nor too high.

Of the 20,547 supplements (421 labeled as prenatal supplements) available on the US market:

Only 69 (0.3%) supplements contained all 6 nutrients they considered essential for a healthy pregnancy.

Only 1 supplement contained all 6 nutrients at the appropriate doses, and it wasn’t even labeled as a prenatal supplement.

If you are pregnant or thinking of becoming pregnant, this should be a wake-up call.

Yet three studies evaluating the adequacy of prenatal supplements have been published in the past few months. And all three studies concluded that the vast majority of prenatal supplements on the market are woefully inadequate.

You may be wondering how I can say that in the face of such overwhelming negative data. That’s because while all 3 studies were very good studies, they each had “blind spots”:

For more details on this study and 7 tips on finding the best prenatal supplement for you, 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.

____________________________________________________________________________

For more detail about FTC regulations for health claims, see this link.

https://www.ftc.gov/business-guidance/resources/health-products-compliance-guidance

Vitamin K And Heart Disease Deaths

January 23, 2018 by Dr. Steve Chaney

Does Vitamin K Reduce Heart Disease Risk?

Author: Dr. Stephen Chaney

You 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

Vitamin 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?

In 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?

There 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.