Ever since I found out a few months ago that I was severely deficient in vitamin D, it seems that it’s there’s been a barrage of health articles on the subject. But this Washington Post article (via MSNBC) is the first to link vitamin D with not only diabetes, but also the big bad obesity epidemic.
The lede reports the alarmist find that: “Millions of U.S. children have disturbingly low Vitamin D levels, possibly increasing their risk for bone problems, heart disease, diabetes and other ailments…” Never minding the fact that my doctor told me that most people are deficient in vitamin D, the researchers of two new studies on the subject go on to make value-based judgments on why this is so:
Low Vitamin D levels are especially common among girls, adolescents and people with darker skin, according to the analysis of a nationally representative sample of more than 6,000 children. For example, 59 percent of African American teenage girls were Vitamin D deficient, [Michal L.] Melamed’s study found.
The researchers and others blamed the low levels on a combination of factors, including children spending more time watching television and playing video games instead of going outside, covering up and using sunscreen when they do go outdoors, and drinking more soda and other beverages instead of consuming milk and other foods fortified with Vitamin D.
“This appears to be another result of our unhealthy lifestyles, including a sedentary society that doesn’t go out in the sun much,” Melamed said.
I’m not debating that too little vitamin D is harmful for children — I’m a big proponent of vitamin D after being prescribed it myself and feeling a surge of energy return just days after taking my first supplement. Instead, what I question are the assumptions the researchers come to as to why children today are deficient. Keep in mind that an accurate measure of vitamin D levels appeared only 15 years ago and that it has taken 5-10 years for it to reach widespread use. The tests are so new, in fact, that doctors are still debating the government’s official guidelines for recommended daily intake. Before this, the only indicator of a vitamin D deficiency was rickets, a deformative softening of the bones condition that is usually brought on by a severe case of vitamin D and also calcium deficiencies usually as the result of famine or starvation. Most people who are deficient in vitamin D don’t even know it as the symptoms can be so vague and are often attributable to other conditions/factors. Children today may be no more deficient than their peers of yesteryears; it may be that we are only now able to accurately measure these widespread deficiencies. Let’s dissect these so-called “unhealthy lifestyles” researchers say are now to blame for childhood vitamin D deficiency:
1. Sedentary lives leading to insufficient sunlight exposure: Vitamin D is often called the “sun vitamin” because our bodies produce it upon exposure to the sun, but sunlight is unreliable and several factors influence its ability to induce vitamin D production: angle of the sun, latitude in which one lives, skin pigmentation and use of skin-care products containing SPF. A MedPageToday article on the two studies notes that researchers lacked information on the children’s exposure to sunlight, so no causality can really be established here.
2. Sunscreen use: This is an “unhealthy lifestyle” choice? Really? What’s unhealthier? The leading type of cancer –skin cancer– or a vitamin D deficiency?
3. Increased soda consumption/Decreased milk consumption: The fact that low vitamin D levels are especially common amongst people of color isn’t surprising considering that 95 percent of black people and the great majorities of other people of color are lactose-intolerant –a genetic fact that is never mentioned in either article (or in milk-drinking campaigns and government guidelines). Many people of color lack a digestive enzyme needed to digest the sugars in milk and while this intolerance usually doesn’t manifest itself until adolescence or adulthood, it can still pose problems for children of color. The fact that the still largely milk-white medical community still recommends fortified milk consumption for healthy vitamin D levels demonstrates a classic case of lingering racial discrimination in health care. Research has shown that an inability to digest milk is not a genetic mutation, but rather a genetic norm — the gene for lactase normally switches off as children are weaned and only a small percentage of humans (namely, white folks) in whom the gene is not turned off are able to drink milk into adulthood. This is why some in the medical community have begun to regard us milk-drinking anomalies as “lactose persistent” instead of labeling those who can’t digest milk as “lactose-intolerant.”
Apart from fortified milk, foods naturally rich in vitamin D are scarce –seafood tops the list, along with some cheeses, yogurts, cereals and juices. Since food is not a reliable source of vitamin D, doctors usually recommend taking supplements, which are available over-the-counter in low doses and by prescription for high doses like mine. The supplements aren’t overly-expensive, but can be pricey for families on a budget when you consider that it first requires a doctor’s visit to determine if a deficiency exists and what dosages are needed, along with seasonal follow-up appointments to determine future dosages. Since people of color tend to be disproportionately poorer than white people, it stands to reason that this may not be a lifestyle “choice” as it is a socio-economic fact of life.
Even more interesting are the medical findings of the studies, which are listed in more detail on the MedPageToday article:
Children with low levels of 25-hydroxyvitamin D were more likely to be overweight and/or obese (P for trend <0.001 for both), but even after the researchers adjusted for age, gender, race/ethnicity, body mass index, socioeconomic status, and physical activity, they found that low vitamin D was often accompanied by high systolic blood pressure, high blood sugar, and metabolic syndrome.
These conditions, which are all risk factors for cardiovascular disease, were present regardless of whether the children were overweight or not, the researchers said.
Missing in both articles is the mention that a chief symptom of metabolic syndrome is weight gain. This may be because many in the medical community believe weight gain not to be a symptom of metabolic syndrome, but rather a cause of it. WebMD’s page on metabolic syndrome states matter-of-factly: “Metabolic syndrome is caused by an unhealthy lifestyle that includes eating too many calories, being inactive, and gaining weight, particularly around your waist.” Since the studies are the first of their kind, more observation is needed, but it stands to reason that if so many children are deficient in vitamin D, then just as many, if not more, adults are also deficient. And if a vitamin D deficiency has been linked to metabolic syndrome and high blood sugar independent of weight, then perhaps not all people with the condition are just lazy, Twinkie-munching couch potatoes with a spare tire or two.