Following the valid advice to stay out of the sun and apply sunscreen when outside has left a surprising number of U.S. adults with a vitamin D deficit, according to recent research. American youth also fall short with this “sunshine vitamin.” So what’s the big deal if someone’s tank is a bit low when it comes to vitamin D? Aside from bone health concerns, sub-optimal vitamin D status has now been linked to a higher risk of developing type 2 diabetes.
Research slated to appear in the January 2012 issue of The Endocrine Society’s Journal of Clinical Endocrinology & Metabolism found that low vitamin D levels in obese children are strongly connected with the likelihood of insulin resistance.
The hormone insulin is the key that unlocks the door of each cell, allowing glucose (sugar) to enter the cell and do its work. When blood levels of glucose rise after a sugary meal, the pancreas makes more insulin to handle the extra load. In some people, this process doesn’t work right. The body makes plenty of insulin, but the cells don’t respond to it as well as they should.
The altered cellular response to insulin is what is known as “insulin resistance” and puts a person on the path to diabetes. When someone has insulin resistance, glucose piles up in the blood, yet the cells are starved for fuel. The extra glucose also spills into the urine, increasing the workload of the kidneys and damaging blood vessels.
Clearly, this scenario would be disturbing for any individual, but is doubly so when a child takes the first steps on the path to diabetes. The current study showed that as vitamin D levels went down in obese children, their degree of insulin resistance went up. While this doesn’t confirm a causal link, it certainly should be setting off alarm bells of concern in terms of vitamin D playing a role of some kind in the development of type 2 diabetes.
The current study compared vitamin D, BMI, blood sugar, insulin, and diet in 411 obese children and 87 healthy weight children. Children who skipped breakfast and drank more soda and juice were more likely to come up short with vitamin D than those with healthier dietary habits. Food sources of vitamin D include fish, milk, eggs, and cheese.
And, as I mentioned before, this study showed that obese children were far more likely to have too little vitamin D than kids at a healthy weight. It stands to reason that these vitamin D-deficient heavy-set kids tend to stay indoors instead of playing outside in the sun where their bodies could be making vitamin D. Once again, healthy foods and regular exercise (especially if it’s outdoors) can save the day.
Stephen C Vogt, PharmD
President and CEO