In some people, the high quantities of omega 3s that are latest in fish oil can augment the danger of bleeding or can affect the time it takes blood to clot. If a man is shooting up that affect bleeding or goes to have surgical procedure, here is of particular worry. Fish oil supplements engage with drug treatments for high blood force, so taking them together might lower a person’s blood pressure too much. Certain species of fish can include high levels of contaminants similar to mercury due to environmental pollutants. Using the oils from contaminated fish could pose a health risk, especially for pregnant or nursing women and for infants. People fitting these descriptions may want to avoid eating cold water fish because of the danger of mercury toxicity.