Vitamin D and Multiple Sclerosis | Preventive Care?

Written by Dr. Steve Chaney on . Posted in current health articles, Vitamins and Health

Author: Dr. Stephen Chaney

 

vitamin d and multiple sclerosisA new study (Mokry et al, PLOS Medicine, DOI: 10.1371/journal.pmed.1001866, August 25, 2015) suggests that people who are genetically prone to low vitamin D levels are at increased risk of developing multiple sclerosis (MS). To understand the importance of this study and what it means for us, we need to first review what is already known about vitamin D and multiple sclerosis.

  • MS is an autoimmune disease in which the immune system attacks the myelin sheath that coats our nerves. Conceptually, that’s the equivalent of a fraying cord on a lamp. Eventually, the cord is going to start shorting out and the lamp won’t work very well. On a very basic level MS is similar. As our myelin sheath is damaged over time, our nervous system starts working less well.
  • The earliest evidence that vitamin D status might be associated with MS was the observation that the prevalence of MS was highest for people who lived in northern regions with little exposure to sunlight.
  • Numerous studies since then have shown that MS patients generally have lower 25-hydroxy vitamin D levels in their blood.

These studies clearly show an association between low vitamin D status and MS, but association does not prove causation. There are two limitations of association studies that significantly reduce their predictive value – reverse causation and confounding factors.Those are both somewhat highfalutin scientific terms, so let me put them in plain English – and in terms that are relevant to our discussion of vitamin D status and MS.

Reverse causation simple means that the MS might have caused low vitamin D status. For example, individuals with MS might spend less time outdoors because of their physical limitations. That would result in less sun exposure, which would decrease their blood levels of 25-hydroxy vitamin D.

A confounding factor would be something else that increased the risk for MS and happened to be associated with low vitamin D status. Suppose, for example, that exercise decreased the risk of MS. People who spend most of their time inside in front of a TV or computer screen would have low levels of exercise and low sun exposure. If it was the lack of exercise rather than the low vitamin D status that actually predisposed to MS, lack of exercise would be a confounding factor for any clinical study comparing vitamin D status with risk of developing MS.

 

What Can Genetics Tell Us About The Relationship Between Vitamin D and Multiple Sclerosis?

does-vitamin-d-prevent-msThe authors of this study had previously identified mutations in 4 genes that decrease blood levels of 25-hydroxy vitamin D (the most commonly used measure of vitamin D status). In this study(Mokry et al, PLOS Medicine, DOI: 10.1371/journal.pmed.1001866, August 25, 2015)they analyzed the frequency of those genetic mutations in 14,498 MS cases compared with 24,091 healthy controls. Their study showed:

  • Genetic mutations that decrease 25-hydroxy vitamin D levels are associated with a significant increase in the risk of developing MS.
  • Based on the relationship of those mutations with 25-hydroxy vitamin D levels, they calculated that every 50% increase in 25-hydroxy vitamin D levels was associated with a 50% decreased risk of developing MS.

This was a very large, well designed study. It has some limitations of its own, but because it used a genetic approach it largely avoids the concern about reverse causation and confounding factors. In short, this study strongly supports the conclusion from previous studies that low vitamin D status significantly increases the risk of developing MS.

The authors concluded “The identification of vitamin D as a causal susceptibility factor for MS may have important public health implications, since vitamin D insufficiency is common, and vitamin D supplementation is both relatively safe and cost effective.”

 

Is Vitamin D Supplementation Effective In Preventing And Treating MS?

Vitamin DThe authors of the study also concluded “These findings provide the rationale for further investigating the therapeutic benefits of vitamin D supplementation in preventing the onset and progression of MS.”

While more studies are still needed, the Nurses’ Health Study (Munger et al, Neurology, 62: 60-65, 2004) provides pretty convincing evidence that vitamin D supplementation can prevent the onset of MS. That study followed 187,563 nurses for at least 4 years, during which time 173 of them developed MS. The study showed that supplementation with 400 IU/day of vitamin D reduced the risk of developing MS by 40%.

The efficacy of vitamin D supplementation in preventing the progression of MS is much less well established. Several studies have shown that low vitamin D status is associated with higher levels MS relapse and more rapid progression of MS symptoms.However, studies of vitamin D supplementation conducted to date have been too small and too short in duration to be definitive.

What Is The Significance Of This Study?

On one hand MS is a very rare disease, affecting around 0.1% of the adult population. On the other hand, it is a debilitating disease. If something as simple as assuring adequate vitamin D status can reduce the risk of developing MS by 40-50%, it is an important public health measure, especially since 40% of the US population has insufficient blood levels of vitamin D (Looker et al, American Journal of Clinical Nutrition, 88: 1519-1527, 2008).

What Does This Study Mean For You?

SunWhat does this study mean for you and me? We already know that adequate vitamin D status is essential for building strong bones, and there is pretty good evidence that adequate vitamin D status is important for a strong immune system. Now we can add autoimmune diseases to the list. It is pretty clear that adequate vitamin D status is important for preventing MS. It may help prevent other autoimmune diseases as well.

One interesting wrinkle for MS is that it may be vitally important to assure adequate vitamin D in our younger years. Studies looking at people who grow up in northern latitudes and then move south and vice versa suggest that the risk of developing MS is much more strongly associated with sun exposure during the first 10-15 years of life than with sun exposure later in life.

It is, therefore, not just important that we assure adequate vitamin D status for ourselves. It may be even more important that we assure that our kids and grandkids have adequate vitamin D status.

The problem is that in today’s world we are told to slather industrial strength sunscreen on ourselves from head to foot before we leave the house and very few foods in nature provide significant amounts of vitamin D, so most of us rely primarily on vitamin D fortified dairy products and supplements to assure adequate intake of vitamin D. Click here for the latest RDA recommendations for vitamin D intake.

Some people do appear to need greater than RDA levels of vitamin D because they don’t metabolize vitamin D efficiently. They can have adequate intake of vitamin D, but their blood levels of 25-hydroxy vitamin D are low. I recommend that you ask your doctor to check your 25-hydroxy vitamin D levels at your next physical. If they are low, work out a vitamin D supplementation regimen with your doctor to bring your 25-hydroxy vitamin D levels into the optimal range.

 

The Bottom Line

  • A recent study showed that genetic mutations which decrease 25-hydroxy vitamin D levels are associated with a significantly increased risk of developing MS. Based on the relationship of those mutations with 25-hydroxy vitamin D levels, the investigators calculated that every 50% increase in 25-hydroxy vitamin D levels was associated with a 50% decreased risk of developing MS. This study strongly supports the conclusion from previous studies that low vitamin D status significantly increases the risk of developing MS.
  • An earlier Nurses’ Health Study has shown that supplementation with 400 IU/day of vitamin D decreases the risk of developing MS by 40%.
  • The authors of the most recent study concluded “The identification of vitamin D as a causal susceptibility factor for MS may have important public health implications, since vitamin D insufficiency is common, and vitamin D supplementation is both relatively safe and cost effective.” I agree.
  • While MS is a very rare disease, it can be devastating. This alone, is a good enough reason to be sure that you maintain adequate vitamin D status.
  • There is evidence that vitamin D status in our childhood years may be more important than our vitamin D status in later years for determining our risk of developing MS. It is, therefore, not just important that we assure adequate vitamin D status for ourselves. It may be even more important that we assure that our kids and grandkids have adequate vitamin D status.
  • While these and other studies demonstrate the health benefits of maintaining adequate vitamin D status, many Americans don’t do a good job of it. Government surveys show that 40% of Americans are deficient in vitamin D. That’s because we are continually being advised to slather on industrial strength sunscreen before we leave the house, and most naturally occurring foods are relatively poor sources of vitamin D.
  • While the evidence that vitamin D supplementation is effective for preventing MS is strong, evidence that vitamin D supplementation can slow the progression of MS is inconclusive at present. More and better studies are needed before we will have a definitive answer to this question.

 

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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Should You Avoid Sugar Completely?

Posted October 24, 2017 by Dr. Steve Chaney

Is It The Sugar, Or Is It The Food?

Author: Dr. Stephen Chaney

 

Should we avoid sugar completely?  Almost every expert agrees that Americans should cut down on the amount of sugar we are consuming. However, for some people this has become a “sugar phobia”. They have sworn that “sugar shall never touch their lips”. Not only do they avoid sugar sweetened sodas and junk food, but they also have become avid label readers. They scour the label of every food they see and reject foods they find any form of sugar listed as an ingredient. Is this degree of sugar avoidance justified?

 

Should We Avoid Sugar to Keep it From Killing Us?

 

Let me add some perspective:

  • If you just take studies about the dangers of sugar at face value, sugar does, indeed, look dangerous. Excess sugar consumption is associated with increased risk of obesity, diabetes, and heart disease. However, when you look a little closer, you find that most of these studies have been done by looking at the correlation of each of these conditions with sugar sweetened beverage consumption (sodas and fruit juices).

A few studies have looked at the correlation of obesity and disease with total “added sugar” consumption. However, 71.6% of added sugar in the American diet comes from sugar sweetened beverages and junk food. None of the studies have looked at the sugar from healthy foods like fruits, vegetables, and whole grains. That’s because there is ample evidence that these foods decrease the risk of obesity, diabetes, and heart disease.

  • For example, if apples had a nutrition label, it would list 16 grams of sugar in a medium 80 calorie apple, which corresponds to about 80% of the calories in that apple. The sugar in an apple is about the same proportion of fructose and glucose found in high fructose corn syrup. Apples are not unique. The nutrition label would read about the same on most other fruits. Does that mean you should avoid sugar from all fruits? I think not.

Avoid Sugar or Avoid Certain Foods

 

avoid sugar from junk foodsThe obvious question is: “Why are the same sugars, in about the same amounts, unhealthy in sodas and healthy in fruits?” Let’s go back to those studies I just mentioned—the ones that are often used to vilify sugars. They are all association studies, the association of sugar intake with obesity and various diseases.

The weakness of association studies is the association could be with something else that is tightly correlated with the variable (sugar intake) that you are measuring. Could it be the food that is the problem, not the sugar?

If we look at healthy foods (fruits, vegetables, whole grains) they are chock full of vitamins, minerals, phytonutrients, fiber, and (sometimes) protein. Fiber and protein slow the absorption of sugar into the bloodstream. As a result, blood sugar levels rise slowly and are sustained at relatively low levels for a substantial period of time.

In sodas there is nothing to slow the absorption of blood sugar. You get rapid rise in blood sugar followed by an equally rapid fall. The same is true of junk foods consisting primarily of sugar, refined flour and/or fat.  Avoid sugar from those types of foods.

Another consideration is something called caloric density. Here is a simple analogy. I used to explain the concept of caloric density to medical students in my teaching days. There are about the same number of calories in a 2-ounce candy bar and a pound of apples (around 278 in the 2-ounce candy bar and 237 in a pound of apples). You can eat a 2-ounce candy bar and still be hungry. If you eat a pound of apples you are done for a while. In this example, the 2-ounce candy bar had a high caloric density (a lot of calories in a small package). Perhaps a more familiar terminology would be the candy bar was just empty calories.

Are Sodas and Junk Foods Killing Us?

avoid sugar from candyPutting all that together, you can start to understand why the foods the sugars are in are more important than the sugars themselves. When you consume sugars in the form of sugar sweetened beverages or sugary junk foods, your appetite increases. We don’t know for sure whether it is the intense sweetness of those foods, the rapid increase and fall in blood sugar, or the high caloric density (lots of calories ina small package) that makes us hungrier. It doesn’t matter. We crave more food, and it isn’t usually fruits, vegetables, and complex carbohydrates we crave. It’s more junk. That sets in motion a predictable sequence of events.

  • We overeat. Those excess calories are stored as fat and we become obese. [Note: The low carb enthusiasts will tell you our fat stores come from carbohydrates alone. That is incorrect. All excess calories, whether from protein, fat, or carbohydrate, are stored as fat.]
  • It’s not just the fat you can see (belly fat) that is the problem. Some of that fat builds up in our liver and muscles. This sets up an unfortunate sequence of metabolic events.
  • The fat stores release inflammatory cytokines into our bloodstream. That causes inflammation. Inflammation increases the risk of many diseases including heart disease and cancer.
  • The fat stores also cause our cells to become resistant to insulin. That reduces the ability of our cells to take up glucose, which leads to hyperglycemia and type 2 diabetes. [Note: The low carb enthusiasts will tell you carbohydrates cause type 2 diabetes. That is also incorrect. It is our fat stores that cause insulin resistance and type 2 diabetes. Our fat stores come from all excess calories, not just excess calories from carbohydrates.]
  • Insulin resistance also causes the liver to overproduce cholesterol and triglycerides and pump them into the bloodstream. That increases the risk of heart disease.
  • Sugar sweetened beverages and sugary junk foods also displace healthier foods from our diet. That leads to potential nutrient shortfalls that can increase our risk of many diseases.

However, none of this has to happen. The one thing that every successful diet has in common is the elimination of sodas, junk foods, fast foods and convenience foods. You should avoid sugar from those foods as much as possible. Once you eliminate those from your diet,you significantly enhance your chances of being at a healthy weight and being healthy long term.

 

What About Protein Supplements And Similar Foods?

Of course, the dilemma is what you, as an intrepid label reader, should do about protein supplements, meal replacement bars, or snack bars. They are supposed to be healthy, but the label lists one or more sugars. Even worse, the sugar content is higher than your favorite health guru recommends.  So, should you avoid sugar from supplements and the like?

In this case, a more useful concept is glycemic index, which is a measure of the effect of the food on your blood sugar levels. Healthy foods like apples may have a high sugar content, but they havea low glycemic index.

avoid sugar and consume protein to slow absorbptionThe same is true for the protein supplements and bars you are considering. Rather than looking at the sugar content, you should be looking for the term “low glycemic” on the label. That means there is enough fiber and protein in the food to slow the absorption of sugar into the bloodstream and stabilize your blood sugar levels.

What Does This Mean For You?

Don’t misunderstand me. I am not advocating for unlimited consumption of sugar. We should work on ways to avoid sugar or reduce the amount of sugar in our diet. On the other hand, we don’t need to become so strict that we and our family need to eat foods that taste like cardboard. We also don’t want to replace natural sugars with artificial sweeteners. I have warned about the dangers of artificial sweeteners previously.

We can go a long way towards reducing sugar by just eliminating sodas, other sugar sweetened beverages, junk foods, fast foods, convenience foods, and pastries from our diet. When considering fast foods and convenience foods, we should check the label for hidden sugar. For example, some Starbucks drinks are mostly sugar. When considering foods that are supposed to be healthy, we should look for the term “low glycemic” on the label.

So we don’t have to avoid sugar completely, but we should reduce sugar from sugar sweetened beverages and junk food.

 

The Bottom Line

 

We need to keep warnings about the dangers of sugar in perspective:

  • The studies showing that sugar consumption leads to obesity, diabetes, and heart disease have all been done with sodas and junk foods.
  • Many fruits have just as much sugar as a soda. They also contain about the same proportion of fructose and glucose as high fructose corn syrup. Yet we know fruits are good for us.
  • Diets rich in fruits, vegetables and whole grains decrease our risk of obesity, diabetes, and heart disease.
  • That is because the sugar in whole foods is generally present along with fiber and protein, which slows the absorption of sugar and prevents the blood sugar spikes we get with sodas and junk foods.
  • In the case of prepared foods like protein supplements, you should look for “low glycemic” on the label rather than sugar content. Low glycemic means that there is enough fiber and protein in the product to slow the absorption of sugar and prevent blood sugar spikes.
  • Don’t misunderstand me. I am not advocating for unlimited consumption of sugar. We should all work on ways to avoid sugar from junk foods or to reduce the amount of sugar in our diet. On the other hand, we don’t need to become so strict that we and our family need to eat foods that taste like cardboard. We also don’t want to replace natural sugars with artificial sweeteners.
  • We can go a long way towards reducing sugar by just eliminating sodas, other sugar sweetened beverages, junk foods, fast foods, convenience foods, and pastries from our diet. When considering fast foods and convenience foods, we should check the label for hidden sugar. When considering foods that are supposed to be healthy, we should look for the term “low glycemic” on the label.

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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