Guidelines and Precautions. The jury is still out on melatoninâs effects on blood pressure. If you have high or low blood pressure, or take medications to control your blood pressure, it is best to avoid the supplement unless advised otherwise by your doctor.uidelines and Precautions. The jury is still out on melatoninâs effects on blood pressure. If you have high or low blood pressure, or take medications to control your blood pressure, it is best to avoid the supplement unless advised otherwise by your doctor.
1 This can cause the can to bulge or rust.  Use canned tuna by the expiration date on the can. If the can doesn't have a best by date, mark it with the date of purchase and use the tuna within 12 to 24 months of purchase.
Frozen fresh, smoked or cooked salmon remains good for up to 9 months. Canned salmon lasts in the pantry for up to 9 months as well. Other seafood, such as fresh crawfish and shrimp, will remain safe for consumption for a period of 1 to 2 days under refrigeration and for up to 6 months in the freezer.