Tag: Latitude

Approximately 90% of the body's vitamin D is synthesized through exposure to sunlight, yet studies show deficiency is a major global health problem affecting millions. While diet and genetics play a role, a significant and often overlooked aspect is the influence of our environment. Understanding these external factors is crucial for prevention.

According to a study published by the WHO, many regions with abundant sunshine still report high rates of vitamin D insufficiency. This global phenomenon is tied to various factors, with certain climates being most likely to cause vitamin D deficiency due to insufficient UVB exposure, regardless of perceived sun availability.

Contrary to common assumptions, several studies have found a high prevalence of vitamin D deficiency in populations residing in sun-rich equatorial regions. This indicates that simply living near the equator does not guarantee higher vitamin D levels, as many complex factors influence synthesis and availability.

Studies show that at latitudes above 35 degrees, people are at a significantly higher risk for vitamin D deficiency during winter months. Latitude is one of the most critical factors influencing the body's ability to produce this essential nutrient from sunlight, creating a clear geographical divide in vitamin D status.

Over one billion people worldwide are estimated to have insufficient vitamin D levels. The short answer is yes, less UV means less vitamin D, but the full picture is far more complex, influenced by your location, season, and individual physiology.

Just after the winter solstice, the daily gain of sunlight is only a matter of seconds, but this accelerates to several minutes per day near the equinox, with the exact amount varying significantly by your location. Knowing how much extra sunlight per day can help in seasonal planning.