Fish intake has been encouraged by nutritionists and physicians for years. Fish are a component of a healthy diet and have been linked to a multitude of health benefits. Fish oil as a supplement has long been touted as a home remedy cure-all (much like coconut oil in recent years). Mother’s used to give cod oil by the spoonful and now there are a variety of pills available on the market. In fact, the NIH states that fish oil supplements are the most common nonvitamin supplement taken in the USA. So does fish oil really work? The answer is unclear.
What makes fish oil so important? Well, our bodies need carbohydrates, proteins and fats to develop and function properly. Some of these elements we can synthesize ourselves but others can’t be made by our bodies. These essential elements have to be obtained from our diet. Fish oil is high in omega-3 fatty acids, mostly DHA and EPA. While these particular omega-3s are not essential (unlike ALA which is found in plant based food), they are difficult to synthesize and it is currently the recommendation that we obtain these fats from our diet. A Harvard blog explains that “omega-3 fatty acids play important roles in brain function, normal growth and development, and inflammation. Deficiencies have been linked to a variety of health problems, including cardiovascular disease, some cancers, mood disorders, [and] arthritis.” So, even though these fatty acids can be made by our bodies, the best dietary source is through fatty fish, such as salmon, sardines, lake trout, albacore tuna, herring, and mackerel. Over the years, as dietary supplementation has grown in popularity, fish oil supplements have gained traction. The concept is that you can reap the benefits of omega-3 fatty acids through pills and by-pass the fishy meals altogether. The question is, does it really work?
An article posted by CNN brings light to the fish oil debate. This discussion has been at the forefront among health experts for many years. In fact, fish oil has been used as a remedy for a myriad of ailments for centuries. Vikings used fish oils in from the 8th to 11th centuries. Europeans used fish oil in the 1700s. By the 1800s, countries around the world were producing and consuming fish oil and fish oil products. The CNN article notes that there is a growing interest in the affects of fish oil on our brains (which are large consumers of omega 3 fatty acids. It cits a 2010 study that revealed ” women who took the supplements during their pregnancy were just as likely to experience postpartum depression as those who didn’t and the brains of their babies didn’t appear to grow and develop more quickly than other babies.” Fish oil intake has also been linked to reduced ADHD intake, reduce brain aging, lower risk of heart disease, weight loss, and possibly increased brain recovery. In fact, Bobby Ghassemi and his family believe that the omega 3 fatty acids helped him recover from his traumatic brain injury.
The CNN article mentioned above sites a new study, aptly titled “Diet during pregnancy and infancy and risk of allergic or autoimmune disease: A systematic review and meta-analysis.” This study aimed to determine if there was a correlation between maternal diet during pregnancy and the development of allergic and autoimmune diseases in infants. For anyone keeping up with the studies relating to the correlation of food exposure and food allergies, such as the never ending debate about peanut exposure (such as this discussion in the NY Times), this study is along the same lines. However, it bypasses the “what age” question by going directly to age zero, fetal development. Babies are exposed to some components in the mother’s blood that can pass through the placental barrier to the fetus. Additionally, mother’s pass things along to their newborn babies through their breast milk. Thus, it makes sense that what mom is exposed to, the baby is exposed to. What she eats, the baby eats. The difference is that this study looked at these things systematically and tried to find a correlation to the infant’s health. The results are clear. The study clearly states, “maternal probiotic and fish oil supplementation may reduce risk of eczema and allergic sensitisation to food, respectively.” (As a side note, the study also put in its 2 cents about the peanut debate by stating “early peanut or egg introduction to the infant diet reduces risk of peanut or egg allergy.”)
On the other hand, it is important to note that not all findings regarding fish oil have been positive. High intake of oily fish has been linked to prostate cancer. Additionally, fish oil from actual fish in your diet, can possibly increase your mercury intake. The American Academy of Pediatrics notes that fish such as shark, mackerel, tuna and varieties of fresh water fish are more likely to contain mercury than other fish. Pregnant women and their babies are especially advised to limit their intake of these types of ocean dwellers. Additionally, fish oil supplements are not well regulated because they are not under the regulation of organizations like the FDA. Thus, the quality of the pills can vary greatly. Additionally, omega-3 fatty acids are relatively unstable molecules that are prone to oxidation. This breaks down the fatty acid chain into other types of fat molecules, essentially lessening the quality of the pills.
Lastly, all of these findings (positive or negative) may be most apparent among subsets of the population and many of these findings have inconsistent results. Additionally, the benefits of omega 3 fatty acids are often not well isolated from the benefits of increased fish intake in and of itself. Eating less red meat, consuming more lean fats, and the vitamins and minerals found in fish alongside these fatty acids may also contribute to positive outcomes, rather than just omega-3 intake alone. Many studies do not study isolated supplement intake or have too weak/inconsistent findings to offer definitive findings that are applicable to the general population. The best advice is vague but true. CNN states “Most health experts recommend that people try to eat a healthy, balanced diet to protect against diseases and most cancers, and turn to supplements only if that’s not possible, since supplements may provide only partial benefits.”