Best Health

VI­TA­MIN D

Sun­light’s a lit­tle hard to come by these days. Are you get­ting enough vi­ta­min D?

- By DIANA DUONG

AS THE DAYS grow shorter and the pos­si­bil­ity of an­other lock­down hangs over us, many peo­ple are turn­ing to vi­ta­min D sup­ple­ments as an easy way to make up for the lack of sun­shine. Healthy lev­els of the vi­ta­min help pre­vent os­teo­poro­sis and frac­tures. Low amounts may be as­so­ci­ated with a higher risk of heart at­tacks and stroke. (More re­search on this link is needed though. It may be that low lev­els of vi­ta­min D are re­flec­tive of gen­eral poor health.) But how do you know if you’re ac­tu­ally de­fi­cient? It’s not an easy cal­cu­la­tion. Skin tone and age make a dif­fer­ence Melanin and age fac­tor into how much vi­ta­min D your body makes. The darker your skin, the more dif­fi­cult it is to get vi­ta­min D from the sun (one of the main de­liv­ery mech­a­nisms), and the older you are, the less able your body is to pro­duce the “sun­shine vi­ta­min.” Pop­u­la­tions that are par­tic­u­larly at risk of de­fi­ciency in­clude Black peo­ple, north­ern Indige­nous peo­ple, peo­ple of colour, peo­ple who are obese, preg­nant women, chil­dren and new­borns.

Ge­og­ra­phy also plays a part

Un­less you had next to no sun ex­po­sure this sum­mer or you live in a high-lat­i­tude area (a study span­ning six years found those liv­ing at a lat­i­tude of 53 de­grees north and higher, such as in Ed­mon­ton, were at pro­nounced risk), you likely have suf­fi­cient stores head­ing into the fall. Vi­ta­min D is stored in our fat tis­sue and has an av­er­age life­time of two months.

Be­ing de­fi­cient isn’t a given

Ac­cord­ing to Sta­tis­tics Canada, a lit­tle more than two-thirds of Cana­di­ans have healthy vi­ta­min D lev­els. The rest are be­low the cut-off point, 10 per­cent of whom are de­fi­cient.

There’s no one def­i­ni­tion of “de­fi­ciency”

There are dif­fer­ent ranges of mild, mod­er­ate or se­vere vi­ta­min D de­fi­ciency, says Dr. Olivia Ok­ereke of the Mas­sachusetts Gen­eral Hos­pi­tal Psy­chi­a­try Depart­ment. “Your vi­ta­min D level has lots to do with your in­di­vid­ual cir­cum­stances: other medical con­di­tions you have, your age, your skin type, how much ex­er­cise or time out­doors you get. There are so many other po­ten­tial risk fac­tors for low vi­ta­min D. It’s more im­por­tant to be in touch with your doc­tor to know what’s ap­pli­ca­ble to you.”

A test and talk­ing with you doc­tor are your best bets

As un­sat­is­fy­ing as it might be, there’s no clear way to know by your­self what your vi­ta­min D sta­tus is, says Ok­ereke. “You might guess that it’s ad­e­quate, and it might be in­ad­e­quate,” she says. “Vi­ta­min D can be mea­sured through a 25-hy­droxy vi­ta­min D test, but it’s not the only marker of vi­ta­min D sta­tus.”

In a re­cent study, led by Dr. Olivia Ok­ereke and pub­lished in JAMA, re­searchers looked at vi­ta­min D sup­ple­ments and whether they could pre­vent de­pres­sion in the gen­eral adult pop­u­la­tion. The study found they had no ef­fect on pre­vent­ing de­pres­sion or boost­ing mood. The re­searchers didn’t, how­ever, look at any other health out­comes, Ok­ereke says, like changes in mem­ory, lung func­tion, or me­tab­o­lism. “There’s a lot more to study.”

 ??  ??

Newspapers in English

Newspapers from Canada