Vitamin D deficiency increases risk of countless health woes (II)

As mentioned, deficiency of vitamin D may increase the risk of countless health woes:

Tooth decay in infants and toddlers

Vitamin D is crucial both to our dental health and the formation of our teeth. 

A study in Pediatrics measured the blood levels of vitamin D in pregnant women, then checked the teeth of their babies at one year old. Researchers found that mothers of children with weak enamel and tooth decay had significantly lower vitamin D levels during pregnancy compared to moms of children with healthy teeth.

Gum disease and tooth loss

The sunshine vitamin has a key role in protecting our teeth as we age. In one study, older adults who took 700 international units (IU) of vitamin D (along with calcium) each day for three years were less likely to lose teeth than those who took placebo pills, even two years after they stopped taking the supplements. Researchers have also reported strong evidence that D deficiency is a risk for gum disease and that it can worsen dental problems once we have them.

Alzheimer's and dementia

Studies have linked low vitamin D to abnormalities in brain structure, cognitive decline and dementia. In a recent study in JAMA Neurology, which measured vitamin D and cognitive function each year in an ethnically diverse group of elderly patients (about half of whom had some form of cognitive impairment at the start of the study), lower levels of D were associated with accelerated cognitive decline.

UTIs (Urinary Tract Infections)

Vitamin D prevents infection by helping our bodies produce natural antibiotics.  A study in Archives of Disease in Childhood found that D deficiency is a risk factor for urinary tract infections in children, especially girls. Low levels are associated with UTIs for adults, too.  A study of women who suffered from recurrent UTIs found that they had lower levels of vitamin D than women who didn't.

Female incontinence

Since vitamin D is critical for muscle strength, deficiency can contribute to weakness in the pelvic floor, i.e. the hammock of muscles that supports the bladder, vagina, uterus, and rectum and lead to urinary incontinence (as well as, potentially, fecal incontinence) in women, according to a 2012 research review published in International Urogynecology Journal. For women who suffer from poor bladder control, maintaining healthy levels of vitamin D could prove to be as important as performing pelvic floor exercises.

Asthma

According to a large Israeli study published in Allergy that tracked more than 21,000 adults with asthma, while people with asthma were no more likely to have low D than those in the general population, asthmatics who did have a vitamin D deficiency were 25% more likely to experience acute attacks.

Schizophrenia

There is a strong link between vitamin D deficiency and this mental health disorder.  In a 2014 review of 19 studies, researchers found that 65% of schizophrenia patients had low levels of vitamin D, and people with vitamin D deficiency were more than twice as likely to have schizophrenia. That correlation does not necessarily mean that deficiency causes schizophrenia. In fact, experts hypothesize that the reverse may be true, with schizophrenia causing people to make lifestyle and diet choices that lead to deficiency.

Depression

Female college students who had low levels of vitamin D were more likely to have clinically significant symptoms of depression, according to a 2015 study published in Psychiatry Research.

Colorectal cancer

A 2011 meta-analysis found that greater vitamin D intake and higher vitamin D levels were linked to lower risk of colorectal cancer. 

On the other hand, a 2006 clinical trial as part of the Women's Health Initiative found that women who took calcium and vitamin D supplements for an average of seven years had no reduction in colorectal cancer risk compared to those who took a placebo.

Pancreatic cancer

People with the highest vitamin D levels were 35% less likely to develop pancreatic cancer than those with the lowest levels, according to a 20-year study of nearly 120,000 people conducted by researchers from Brigham and Women's Hospital in Massachusetts.

Prostate cancer

Low levels of vitamin D were associated with more advanced, aggressive prostate tumors in biopsy patients in a 2014 study in Clinical Cancer Research.  

Among African American men, low vitamin D was also associated with a higher risk of developing prostate cancer in the first place. A small pilot study from the Medical University of South Carolina in Charleston found that when prostate cancer patients received 4,000 IU of vitamin D per day for 60 days, 60% of them showed improvement in their tumors.