Vitamin D’s effect on women’s health

Vitamin D’s effect on women’s health

A major role in a woman’s health is obtaining sufficient nutrients from her daily diet.  One of the most critical nutrients all women should be mindful of is vitamin D. Obtaining sufficient vitamin D whether from food sources, the sun or supplements, is important for everyone but women will want to take note of making sure their vitamin D status is adequate. 

What is vitamin D?

Vitamin D, aka the “sunshine vitamin” since it can be made from exposure to ultraviolet light, is a fat-soluble vitamin that acts as a hormone. Because vitamin D can be made in the body, it is essential in the diet only when exposure to sunlight is limited or the body’s ability to synthesize it is reduced.  Whether vitamin D is obtained from food sources or the sun, it is inactive until it is modified by biochemical reactions in the both the liver and the kidneys.

Vitamin D is just as critical for women as it is for men.  More and more studies have come out showing the various benefits vitamin D provides and why this fat-soluble vitamin is one not to become deficient in.

Vitamin D has many important functions in the body including:

·      Mineralization of bones and teeth

·      Absorption of calcium and phosphorus

·      Cell differentiation

·      Immunity

·      Blood pressure regulation

Causes of vitamin D deficiency in women

Women appear to have lower vitamin D levels than men for several reasons:

·      Women tend to have more body fat than men.  Being obese or having more body fat is an important factor in lowering vitamin D levels because fat cells absorb vitamin D and keep it from circulating throughout the bloodstream.

·      Women tend to spend less time outdoors than men with adequate exposure to the sun.  Women may also be more likely to use sunscreen blocking UV light for making vitamin D in addition to wearing hats or clothing with long sleeves or pants.

·      As we age, whether a woman or man, less vitamin D is absorbed from dietary sources and our bodies produce less vitamin D in their skin from the sun. 

·      If a woman lives above the 42nd parallel – from Chicago or Boston north – the months of November through February do not produce sufficient vitamin D even on a sunny day. 

Testing for vitamin D status

Vitamin D status is checked with a blood test called a 25(OH)D blood test.  This can be done at a doctor’s office and it will show whether a person is getting enough vitamin D or not and if they need to take a supplement or not. 

The Vitamin D Council has the following standards regarding vitamin D status:

Deficient – 0-30 ng/ml

Insufficient – 31-39 ng/ml

Sufficient – 40-80 ng/ml

Toxic - >150 ng/ml

The Endocrine Society has different standards and recommends these ranges:

Deficient – 0-20 ng/ml

Insufficient – 21-29 ng/ml

Sufficient – 30-100 ng/ml

What does a vitamin D deficiency mean for a woman?

If a woman is deficient in vitamin D, it can affect her health in many ways:

·      Breast cancer – Studies have shown women with sufficient vitamin D levels had a 45% decreased risk of breast cancer.  Other studies have found that women diagnosed with breast cancer had, on average, lower blood levels of 25(OH)D.

·      Ovarian cancer – The impact of vitamin D on ovarian cancer has not been as well studies but it is reported to have a protective effect.  A recent study found that sufficient vitamin D status appears to delay progression of ovarian cancer.

·      Cardiovascular disease – A growing number of studies point to vitamin D deficiency as a risk factor for heart attacks, congestive heart failure, peripheral arterial disease, and strokes.  Even though more large scale studies are required, a recent 2016 study suggest that daily vitamin D supplementation may reduce cardiovascular risk factors.

·      Depression – There have been studies suggesting that supplements of vitamin D may improve mild depression.  At this point, treatment with high dose supplements of vitamin D for depressive symptoms is considered experimental and should only be used with medical supervision.

·      Lupus – Lupus is a chronic autoimmune disease that can affect almost any organ system in the body with multiple symptoms. About 9 out of 10 adults with lupus are women ages 15 to 45.  Vitamin D has been found to have effects on immune function and inflammation with studies suggesting a relationship of vitamin D to autoimmune conditions. This may suggest a possible connection of low vitamin D status and lupus. 

·      Osteoporosis – Postmenopausal women are at a higher risk of the brittle bone disease of osteoporosis.  In order for calcium to be absorbed and deposited into bone, there must be sufficient vitamin D for this to happen.  Women, who have had a low calcium intake over the years along with insufficient vitamin D, are more likely to develop osteoporosis as they age.  Women obtaining adequate vitamin D along with calcium throughout their lifetime appear to have a reduced risk of osteoporosis. 

Sources of vitamin D

Best sources of vitamin D include the following:

·      Sunlight – Between 10-20 minutes of sun exposure on arms and legs or face 3 times weekly between 10 am to 3 pm.

·      Food sources:

·      Cod liver oil

·      Cooked salmon

·      Sardines in oil

·      Tuna in oil

·      Vit. D fortified orange juice

·      Vit. D fortified milk

·      Vit. D fortified yogurt

·      Egg yolk

·      Vitamin D supplements

It is best to consult with your physician on the amount to take if using a vitamin D supplement. Generally, most adults can safely take up to 2000 IU of vitamin D3 a day for maintenance.  In the meantime, get adequate sun exposure, increase food sources of vitamin D and always discuss with your physician of the need for a vitamin D supplement.