LOS ANGELES (AP) — Multivitamins might help lower the risk for cancer in healthy older men but do not affect their chances of developing heart disease, new research suggests.

Two other studies found fish oil didn’t work for an irregular heartbeat condition called atrial fibrillation, even though it is thought to help certain people with heart disease or high levels of fats called triglycerides in their blood.

The bottom line: Dietary supplements have varied effects and whether one is right for you may depend on your personal health profile, diet and lifestyle.