Could low vitamin d levels cause constant hunger? Blood test has <27 for 25-hydroxy vitamin d.

No. Normal level is 30-100. Your level is below normal in which it canaffect bones, can cause osteoporosis, affect autoimmune function, and cardiovascular risks., but not cause hunger.
No. Normal level of vitamin is 30-100. Vit d helps prevent osteoporosis, helps with calcium absorption, responsible for autoimmune function, and heart health as well. Your level is below normal.It would affect the bones, the immune function and cardiovascular risks., but not cause hunger.
Possibly. Vitamin d has many functions. Low vitamin d can contribute to Insulin resistance , elevate cortisol levels and impact other hormones including thyroid hormone. These problems can destabalize your blood sugar and make you hungry.