"Vitamin D Deficiency: The Pacific Northwest Paradox"

By Franklin Everett Shaw

May 10, 2026

The Pacific Northwest: a land of breathtaking beauty, lush forests, and… perpetual gray skies. This idyllic setting, however, hides a silent threat to the well-being of its residents: widespread Vitamin D deficiency.

Forget generic advice about “getting some sun.” For those of us living in Seattle, Portland, or even smaller towns like Astoria, Oregon, relying on sunshine alone is a recipe for disaster. We need a hyper-localized, proactive approach to Vitamin D supplementation.

The problem is multifaceted. The latitude of the Pacific Northwest means that even on sunny days, the sun’s rays are often at an angle that prevents our skin from efficiently synthesizing Vitamin D, especially during the fall and winter months.

Consider Seattle. The city averages only 71 sunny days per year. Portland fares slightly better, but still falls far short of the sunshine needed for adequate Vitamin D production.

This lack of sunlight is compounded by regional dietary habits. Unlike the Midwest, where fortified dairy products are more prevalent, the PNW tends to favor alternative milk sources and a diet less reliant on traditional dairy.

This means we’re missing out on a key source of Vitamin D that many other Americans take for granted.

So, what’s the solution? Year-round supplementation, tailored to the unique conditions of the Pacific Northwest.

Let’s break down a practical guide, focusing on actionable steps you can take today.

First, get tested. Don’t guess; know your baseline Vitamin D level. A simple blood test, ordered by your doctor or through a direct-to-consumer lab like Everlywell, will reveal your current status. Aim for a level between 40-60 ng/mL.

Next, choose the right supplement. Vitamin D3 (cholecalciferol) is the most effective form. Avoid Vitamin D2 (ergocalciferol), which is less potent and not as well absorbed.

Dosage is crucial. The Recommended Dietary Allowance (RDA) of 600 IU per day is often insufficient for PNW residents.

Here’s a more realistic guideline, adjusted for our region’s unique challenges:

• If your Vitamin D level is below 30 ng/mL: Start with 5,000 IU of Vitamin D3 daily for 2-3 months, then retest.
• If your Vitamin D level is between 30-40 ng/mL: Take 2,000-3,000 IU of Vitamin D3 daily.
• For maintenance (levels above 40 ng/mL): 1,000-2,000 IU daily, adjusted based on sun exposure.

Consider the time of year. During the summer months (June-August), when we do get more sun, you might be able to reduce your dosage slightly. However, don’t eliminate supplementation entirely.

Where to buy? Local pharmacies like Bartell Drugs (Seattle area) and Fred Meyer (Oregon and Washington) offer a wide selection of Vitamin D3 supplements. Look for reputable brands like Nature Made, NOW Foods, or Thorne Research.

Avoid gummy vitamins. They often contain less Vitamin D than advertised and are loaded with sugar. Opt for capsules or softgels.

Common mistakes and pitfalls:

• Assuming you’re getting enough Vitamin D from your diet. Unless you’re actively consuming fortified foods or fatty fish (salmon, tuna, mackerel) regularly, you’re likely deficient.
• Not taking Vitamin D with fat. Vitamin D is a fat-soluble vitamin, meaning it’s best absorbed when taken with a meal containing healthy fats.
• Ignoring the impact of sunscreen. While sunscreen is essential for protecting against skin cancer, it also blocks Vitamin D synthesis. If you’re spending time outdoors with sunscreen, you’ll need to supplement even more.
• Thinking that a multivitamin provides enough Vitamin D. Most multivitamins contain only a small amount of Vitamin D, often not enough to correct a deficiency.
• Not retesting your Vitamin D levels. It’s crucial to monitor your progress and adjust your dosage accordingly.

Let’s talk about specific scenarios. Imagine you live in Astoria, Oregon, a coastal town known for its fog and rain. You work indoors and rarely spend time outside. In this case, a higher dose of Vitamin D (3,000-5,000 IU daily) is likely necessary, especially during the winter months.

Conversely, if you live in Bend, Oregon, which enjoys more sunshine than other parts of the state, you might be able to get away with a lower dose (1,000-2,000 IU daily), particularly during the summer.

Remember, Vitamin D deficiency can manifest in various ways, including fatigue, bone pain, muscle weakness, and even depression. Don’t dismiss these symptoms as simply “winter blues.”

Taking proactive steps to optimize your Vitamin D levels can significantly improve your overall health and well-being, especially in the challenging climate of the Pacific Northwest.

Don’t let the gray skies get you down. Take control of your health and embrace the power of Vitamin D supplementation. It’s a small investment that can yield significant returns.