Stroke, or brain attack, is the 3rd leading cause of mortality in the United States.  Each year, over 140,000 Americans die because of stroke, and 500,000 people are left temporarily or permanently disable.  The condition is primarily caused by the absence of blood flowing to the brain, depriving the organ of its much needed oxygen and nutrients.

Deficient vitamin D levels increases stroke risk twice over in white people, but not in blacks.    This is according to a team of researchers coming from Johns Hopkins.  Vitamin D is an essential nutrient obtained from the rays of the sun as well as in various food sources.

Vitamin D and Stroke

According to the researchers, their research findings supports evidence obtained from previous studies at Johns Hopkins, associating vitamin D insufficiency to higher death rates, cardiovascular diseases and the development of peripheral artery diseases in most adults.  The findings will be presented at the yearly Scientific Sessions of the American Heart Association, to be held on November 15 in Chicago.

The research team from Johns Hopkins said that the results of the study failed to explain the reason behind high stroke rates among African Americans, who are obviously expected to have insufficient levels of vitamin D because of their dark skin pigment.  The dark pigmentation present in the skin of African Americans blocks the rays of the sun which is an important source of vitamin D. The study involved 176 participants who died because of stroke in a period of 14 years, 60 of whom were black, and 116 participants were white.  Nonetheless, African Americans are 65% more likely to suffer from severe bleeding in the brain, or a disruption of blood flowing to the brain compared to whites, when vitamin D insufficiency, age and other known stroke risk factors were included in the analysis.

Dr. Erin Michos, M.H.S., a co-lead investigator of the study, said that higher rates for diabetes and hypertension explain why black people have excess stroke risk in contrast to whites.  But the 65 percent risk is far too much, Michos emphasized.  She thinks that there might be other reasons behind the said problem but deficits in vitamin D is not one of them.  She further reiterated that vitamin D deficiency should not be blamed for the high rates of stroke among black people.

Almost 8,000 primarily healthy women and men of both races were included in the recent study, which is actually a part of a bigger, national health status evaluation that is in progress.  The researchers evaluated the risk of death due to stroke between people who have high amounts of vitamin D to those with the lowest vitamin D levels in their blood.  Data revealed that 32.3% of black people and 6.6% of whites possessed very low levels of vitamin D in their blood – which as not more than 15 ng/ml.

Furthermore, Dr. Michos said that the probable explanation for this is that blacks may have adapted to the chronic deficiency in vitamin D which is already present for generations. There is no need, therefore, to increase the levels of vitamin D in blacks in order to equate with the vitamin’s levels in whites just to lessen stroke risk. She advised that the recorded mortality rate of blacks due to stroke may not be statistically sufficient to associate it with deficient vitamin D.

The study was funded by the P.J. Schafer Cardiovascular Research Fund and the American College of Cardiology.

Why do we need vitamin D?

Vitamin D is a fat soluble vitamin that helps in the absorption and breakdown of phosphorus and calcium.  Phosphorus is needed for the maintenance of healthy teeth and bones as well as for energy metabolism and maintaining the balance of acids and bases in the body.  Calcium, on one hand, is important in constructing, forming and maintaining teeth and bones. So this explains why deficient levels of vitamin D can affect the levels of Phosphorus and Calcium in the body.

Aside from its important function in maintaining healthy bones, vitamin D has an important role in the preventing the growth of abnormal cells and in strengthening the immune system. Insufficient levels of vitamin D have been linked to higher rates of depression and breast cancer, especially among the elderly.

Previous studies have been conducted with regards to the health benefits of vitamin D.  Here are some examples:

• According to scientists from Children’s Hospital Boston, Massachusetts General Hospital and University of Colorado Denver School of Medicine, vitamin D may be an essential way to boost the immune system from conditions like the common cold.
• The director of the Multiple Sclerosis and Neuroimmunology Center of the Oregon Health and Science University, Dennis Bourdette, said that vitamin D may decrease the risk of multiple sclerosis.
• A study involving 3000 European men, with ages ranging from 40 to 79 years, revealed that vitamin D may play a role in maintaining brain health, especially on the later part of life.
• In a research conducted at Georgia, USA’s Medical College, results revealed that vitamin D is possibly associated to the maintenance of a healthy weight.
• Vitamin D can also reduce the frequency and severity of asthma symptoms, and reduce the possibility of asthma-induced hospitalizations.  This is according to a study conducted by the researchers of Harvard Medical School after they have monitored 616 children located in Costa Rica.
• Women with high risk of rheumatoid arthritis can also benefit from vitamin D.

Sources of Vitamin D

Dr. Michos suggests that people should make sure that they maintain healthy levels of vitamin D by the regular intake of fish such as tuna and salmon.  She also recommends daily sun exposure for brief periods to take advantage of the sun’s ultraviolet light which produces vitamin D. 10-15 minutes of sun exposure is advised.

Some of the top healthy sources of vitamin D are:

• Salmon
• Tuna
• Cod Liver Oil
• Mushrooms
• Oatmeal
• Sweet Potatoes
• Dandelion Greens
• Egg Yolks

Sources
algaecal.com
medicalnewstoday.com
naturalways.com
eurekalert.org