Type 2 diabetes (T2D) is a condition where the body struggles to manage blood sugar levels. Researchers wanted to know if taking vitamin D could help people with T2D keep their blood sugar under control. They studied 39 trials with nearly 3,000 participants and looked at several health markers, including fasting blood sugar (FBG), a measure of average blood sugar over time (HbA1c), and how well the body uses insulin.
The study found that vitamin D supplementation can improve blood sugar control in people with T2D. On average, people who took vitamin D had lower fasting blood sugar, better insulin function, and lower HbA1c levels. The improvements were most noticeable in people who were vitamin D deficient, overweight, or had poorly controlled diabetes (high HbA1c).
The researchers also discovered that the dose and duration of vitamin D supplementation mattered. High doses over a short period worked best for improving blood sugar levels. Vitamin D seems to help by boosting the body’s insulin sensitivity and reducing inflammation, which can damage insulin-producing cells in the pancreas.
This study suggests that vitamin D supplements could be a helpful addition to the usual treatments for type 2 diabetes, like diet, exercise, and medications. However, it is important to take the correct dose, as taking too much vitamin D can be harmful. The study recommended taking 2000 IU of vitamin D daily. If you have diabetes, talk to your doctor about whether vitamin D supplements might be right for you.