Yes, as a diabetic, you can take fish oil supplements.
Fish oil supplements are typically used to help lower risk of heart disease. Since patients with diabetes are at a high risk of developing heart attacks and strokes, it makes sense to take a supplement that may possibly reduce your risk.
Fish oil in large amounts (over 6 grams a day) are used to help with lowering triglycerides in patients who typically have triglycerides levels over 500. In lower doses like those found over-the-counter, they are used more for their antioxidant properties.
Fish oil supplements are typically very well tolerated and have minimal, if any, side effects apart from the fishy taste that some patients complain about. However, there are different formulations available now that may help with this if it becomes a problem.
Fish oil is not known to increase glucose (i.e. blood sugar) levels, so they can be taken safely in a diabetic patient.
Fish oil is also a pretty benign product and likely will not interact with any of the chronic medications that you take to control your diabetes.
Fish oil is typically a well-tolerated supplement that can potentially help with preventing heart disease. This should be a helpful addition to your daily medication regimen as your diabetes diagnosis places you at a higher risk of having a heart attack or stroke in the future.
If you are taking fish oil for your high triglycerides you will need to get a prescription from your physician as taking 6 grams of fish oil a day will require you take up to 20 pills of the over the counter supplement to get the high dose of fish oil that is recommended.