If the Northwest’s famously dark winters make you feel blue, you’re not alone. Vitamin D deficiency commonly ails Northwesterners between November and March. Research shows Vitamin D deficiency may be tied to an increased risk of cancer, heart disease, stroke, diabetes, and autoimmune diseases. It helps our bodies absorb calcium and without it we’re susceptible to bone diseases like osteoporosis and rickets.
Vitamin D may also improve muscle recovery and prevent exercise soreness. It may alleviate bouts of the blues that crop up this time of year and decrease your chance of developing seasonal affective disorder (SAD).
Most people associate Vitamin D with the sun—and rightly so. Sunlight makes our bodies create Vitamin D and you can soak up a week’s worth in just 15 to 20 minutes. But around 40 to 75 percent of people lack the recommended amount of Vitamin D, with likely higher percentages in the Northwest.
If you think you suffer from Vitamin D deficiency, a simple blood test will determine your body’s levels. Consult with your doctor to see if you should take supplements, and if so, how much to take each day. Because Vitamin D is fat-soluble, it is possible to overdose.
Research indicates that most Northwesterners should take a daily supplement of 1000 to 2000 international units (IU) of Vitamin D even though the recommended daily dosage for the average adult up to age 69 is 600 IUs per day and 800 for adults 70 and over. Still, the FDA sets the Daily Value for Vitamin D at 400 IUs, so if you’re looking at the nutrition facts on food packaging, keep that in mind for serving sizes.
Vitamin D also occurs naturally in a range of foods. Fatty fish like salmon, trout, mackerel, tuna, and eel provide it, and a three-ounce piece of sockeye salmon contains around 450 IUs. Fortified milk—the cartons that are specifically labeled Vitamin D-enriched—and fortified orange juice also provide the nutrient. The serving amount differs by brand.
Egg yolks contain Vitamin D as well, with about 40 IUs per yolk. Fortified cereals like Multi Grain Cheerios contain added Vitamin D, as does beef liver, however unappealing that may sound. Cod liver oil provides a high amount of the nutrient, with about 1,300 IUs per tablespoon. It often comes in capsule form. Small amounts of Vitamin D—around 25 IUs per serving—are also found in ricotta cheese.