Krill Oil 101: Health Benefits, Side Effects, Who Should Take It & More
Before you rush to your local pharmacy or pharmacy, know this: krill oil is not for everyone. “If you have fish allergies or take blood thinners, consult your health care provider before taking krill oil supplements,” Retelny says.
Fish oil and krill oil can cause blood thinners in some people, so it’s important for people taking blood thinners (or who have bleeding disorders or who are going to have surgery) to consult their doctor before taking them, the Cleveland Clinic Remarks. As for people allergic to fish, the American College of Allergy, Asthma and Immunity agrees that you should speak with your doctor before taking any marine supplement.
Although doctors may suggest that pregnant women take fish oil (for example, American Pregnancy Association note that omega-3s can positively impact pregnancy), you may want to stick with fish oil if you’re pregnant or breastfeeding. “Since there is not much research on the effects of krill oil, pregnant or breastfeeding women are advised not to take krill oil,” says Kimberlain.
“Plus, it can interact with other medications people are taking,” Kimberlain says. In people with diabetes, for example, some classes of oral medications may not be as effective, so it’s important to discuss your plan with your doctor or dietitian before starting, she says.
Also, if you have a sensitive stomach and don’t like fish, this might not be for you. “I wouldn’t call it a risk, but a lot of people note that krill oil supplements taste fishy,” Kimberlain says. Some other symptoms or side effects may also be possible, such as diarrhea, heartburn or upset stomach, she adds.
And a word of warning in general about dietary supplements: US Food and Drug Administration (FDA) does not approve supplements before they are marketed, and supplement companies do not have to provide the FDA with information about why their products are safe, the organization notes. Thus, it is important to exercise caution when using supplements and to ask your doctor before starting.
For this reason, Kimberlain suggests that you try to up your seafood game before considering a supplement. “I always suggest a food-first approach,” she says. You can get omega-3 fatty acids by adding fatty cold-water fish, such as salmon, trout, herring, mackerel, and sardines, to your weekly menu. If you don’t eat seafood, you can also get omega-3s from flaxseeds, chia seeds, and walnuts, according to the NIH.
A study published in 2018 in the Journal of Nutritional Sciences one group of study participants ate fish, while the other received krill oil capsules. They found that eating fish increased the study participants’ vitamin D levels, but those in the krill oil group did not see this benefit (however, eating fish and taking a krill supplement both provided health benefits to their respective groups, the researchers note).
If you decide to take krill oil, carefully follow the dosage instructions on the box or bottle. This is because taking too much fish oil (or krill oil) can increase your risk of bleeding and potentially impact how your immune system reacts, the Mayo Clinic Remarks.