Bay leaves have been shown to improve insulin function. Bay leaves may be important in the prevention and/or alleviation of type 1 diabetes.  Fifty five people with type 1 diabetes were divided into two groups, 45 given capsules containing 3 g of bay leaves per day for 30 days and 10 given a placebo capsules. Results All the patients consumed bay leaves shows reduced serum glucose with significant decreases 27% after 30 d. Total cholesterol decreased, 21 %, after 30 days with larger decreases in low density lipoprotein (LDL) 24%. High density lipoprotein (HDL) increased 20% and Triglycerides also decreased 26%. There were no significant changes in the placebo group. Conclusion, this study demonstrates that consumption of bay leaves, 3 g/d for 30 days, decreases risk factors for diabetes and cardiovascular diseases and suggests that bay leaves may be beneficial for people with type 1 diabetes.

Another study was to determine if bay leaves may be important in the prevention and/or alleviation of type2 diabetes. Sixty five people with type 2 diabetes were divided into two groups, 50 given capsules containing 2 g of bay leaves per day for 30 days and 15 given a placebo capsules. All the patients consumed bay leaves shows reduced plasma glucose with significant decreases 30% after 30 days. Total cholesterol decreased, 22%, after 30 days with larger decreases in Low Density Lipoprotein (LDL) 24%. High-Density lipoprotein (HDL) increased 18% and Triglycerides also decreased 25%. There were no significant changes in the placebo group. In conclusion, this study demonstrates that consumption of bay leaves, 2 g d^-1 for 30 days, decreases risk factors for diabetes and cardiovascular diseases and suggests that bay leaves may be beneficial for people with type 2 diabetes.

Bay leaf is a good source of vitamin A, vitamin B6, and vitamin C. These vitamins are all known to support a healthy immune system. Bay leaf is a good source of vitamin A, vitamin C, vitamin B6, calcium, iron, and manganese. 

Bay leaves also contain small amounts of many vitamins and minerals. The most prevalent are:

• Calcium

• Copper

• Iron

• Magnesium

• Manganese

• Vitamin A

• Vitamin B6

• Vitamin C

• Riboflavin

• Zinc