• African Americans – melanin reduces the skin’s ability to make vitamin D
• Those with limited exposure to sunlight
• Breastfed infants – mother’s milk does not contain enough vitamin D
• Elderly – less able to convert vitamin D to its active form
• Vegetarians that follow a strict plant-based diet
• People with certain intestinal problems, such as celiac disease
• Obese people – excess fat impedes the circulation of vitamin D
