Health researchers are alerting that a lack of vitamin D — impacting about 40 percent of adults in the U.S. — is fueling an unnoticed crisis of immune system issues, bone weakening, heart disease, and mental health problems. Unlike numerous other deficiencies, low vitamin D levels seldom show immediate signs, enabling it to covertly harm the body over extended periods. Physicians indicate that straightforward blood assessments and modifications to one's diet can help reverse this issue, yet many Americans have not undergone testing.
