Does Fish Oil Help You Lose Weight?

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    Fish oil may be a helpful tool for weight loss. Rich in omega-3s, fish oil may help suppress appetite, boost exercise performance, and increase metabolism.

    Fish oil is a rich source of omega-3 fatty acids, which has many health benefits, including with weight loss and weight management generally. It has been found that fish oil may reduce your appetite and cravings, help you exercise more efficiently and effectively, increase your metabolism, and even reduce fat storage in the body. In this article, we will take a closer look at the evidence behind these claims, so you can decide whether fish oil is right for you.

    What Are Omega-3s?

    Omega-3s are a type of essential fatty acid that our bodies cannot produce on their own. They are mainly found in fish oil, although there are plant-based sources such as flaxseed and chia seeds. Omega-3s are crucial for many aspects of our health, but especially for supporting heart health, brain health, and eye health.

    There are three main types of omega-3s: EPA (eicosapentaenoic acid), DHA (docosahexaenoic acid), and ALA (alpha-linolenic acid). EPA and DHA are primarily found in fish oil and seafood, while ALA is predominantly found in plant-based sources. EPA and DHA have been extensively studied for their benefits on cardiovascular health.

    The American Heart Association recommends supplementing with omega-3s if you do not eat fish at least 2 times a week. If you follow a vegan diet, not to worry – as there are algae supplements that contain EPA and DHA.

    How Fish Oil May Help With Weight loss

    The omega-3 fatty acids found in fish oil can have an impact on several areas related to weight management, such as promoting satiety, boosting metabolism, improved exercise performance, and managing the stress response. We are going to delve into the science behind these findings in more detail.

    May reduce appetite

    Fish oil has been a popular supplement for many years, and its potential to help manage appetite has been the subject of much debate. Some studies have found that fish oil may increase appetite, while others suggest that it may actually suppress appetite or promote satiety. For instance, this study found that those who consumed diets high in omega-3s had increased satiety 2 hours after meals.

    One theory behind fish oil's potential to reduce appetite is its high content of omega-3 fatty acids. These fatty acids have been linked to increased levels of the hormone leptin, which is responsible for regulating fullness and suppressing appetite. However, there are also studies that contradict these findings. The mixed evidence points to the need for further research into how fish oil affects our eating habits.

    If you are looking for a natural way to promote satiety and reduce cravings, ashwagandha and shatavari may be better options. There is stronger evidence behind these adaptogenic herbs for promoting feelings of fullness and satisfaction after meals.

    May boost exercise effects

    Fish oil supplements have become increasingly popular among fitness enthusiasts, and for good reason. Recent studies suggest that taking fish oil supplements with regular aerobic exercise, such as running or cycling, improves overall body composition and cardiovascular health.

    One study found that well-trained cyclists who were supplemented with 8 grams of omega-3s resulted in lower heart rates during exercise, as well as improved oxygen consumption. These findings have important implications for athletes and fitness enthusiasts looking to maximize their workout results. By taking fish oil supplements, they may be able to enhance their cardiorespiratory fitness levels, enabling them to push themselves further during workouts and achieve better results.

    While there have been numerous studies conducted showing the positive correlation between fish oil supplementation and improved cardiorespiratory endurance, there are also studies that do not report significant findings. There is also stronger evidence behind the use of protein powder and creatine supplementation.

    May increase metabolism

    Recent studies have found that fish oil may also have the ability to speed up metabolism. Metabolism refers to the chemical processes in our bodies that convert food into energy. When our metabolism is working efficiently, we burn calories at a faster rate, which can lead to weight loss, as well as better absorption of nutrients.

    One study that was conducted on healthy females found positive changes in metabolism in those who were supplemented with 3 grams of EPA and DHA over a 3-month period. More specifically, their resting metabolic rate increased by 14%, energy expenditure during exercise by 10%, and the rate of fat oxidation during rest by 19%. Researchers believe that the omega-3 fatty acids found in fish oil can play a key role in stimulating metabolic activity.

    While more research is needed to fully understand the link between fish oil and metabolism, this study provides promising results for those looking to boost their body's natural fat-burning mechanisms. However, the best evidence we have for boosting metabolism lies in adequate nutrition and regular physical activity.

    May improve muscle growth

    Research has shown that fish oil may have the potential to boost muscle growth, most likely due to fish oil aiding in the reduction of cortisol levels. Cortisol, also known as the “stress hormone,” is responsible for breaking down muscle tissue. By decreasing cortisol, fish oil may help promote an environment that is conducive to muscle growth and repair.

    One study found that individuals who were supplemented with 4 grams of fish oil per day (1600 EPA and 800 DHA) over a 6-week period had increases in muscle mass and lower cortisol levels. On the other hand, another study reported that there were no changes in skeletal muscle mass in those who were supplemented with high doses of fish oil.

    At the end of the day, high protein intake and resistance exercise remain the most effective ways to promote muscle growth. Protein is essential for repairing and building muscle tissue, while resistance exercise stimulates muscle hypertrophy through mechanical tension.

    While fish oil may not be a game-changer when it comes to promoting muscle growth, it still has many potential health benefits for our cardiovascular health and endurance. Therefore, incorporating fish oil into a well-rounded fitness routine that includes high protein intake and resistance exercise can still be extremely beneficial.

    Reduces stress

    Fish oil has been found to be an effective way to manage mental stress, making it a valuable addition to anyone's daily routine. Mental stress can have a wide range of negative effects on the body, from impacting cognitive function and memory retention to causing physical symptoms, like occasional headaches and muscle tension. When levels of stress are high, cortisol levels also increase. Frequent, high levels of circulating cortisol can cause an array of negative effects on the body.

    As mentioned above, studies have shown that regularly taking fish oil supplements can help decrease cortisol levels in the body. Decreased cortisol levels can help manage feelings of stress and tension. This randomized, controlled trial found that four months of omega-3 supplementation led to a profile of stress resilience and lower overall levels of cortisol levels during times of stress.

    There is also evidence that adaptogens, such as ashwagandha and shatavari, as well as regular meditation are good ways to help manage mental stress in addition to deep breathing, meditation, and exercise.

    Dosage and Safety

    It is important to understand the recommended dosage and potential safety concerns associated with fish oil supplements. The proper dosage of these supplements is based on an individual’s specific needs and health status. It is generally recommended to consume 1-2 grams of EPA and DHA, the active ingredients in fish oil, per day for general health maintenance. As doses vary from product to product, be sure to look at the label and always talk to your doctor about what kind of supplements you are currently taking or planning to take. If you have allergies, scan the ingredients on the label to avoid any potential allergens or unwanted ingredients. Most importantly, you will ideally want to look for supplements that are C.L.E.A.N certified, third-party tested, non-GMO, and sustainably sourced.

    While fish oil supplements are generally considered safe, it is important to be aware of potential side effects, such as digestive discomfort and fishy burps. Additionally, excessive consumption can increase the risk of bleeding or interact with certain medications such as blood thinners.

    Omega-3 Food Sources

    Since our bodies are not able to produce omega-3s on their own, it’s vital that we obtain these essential nutrients through our diet! Seafood is known to be an excellent source of omega-3s, specifically EPA and DHA. These two types of omega-3s are found in oily fish like salmon, mackerel, and sardines.

    Those who avoid or do not consume seafood products due to personal preferences or dietary restrictions can still get their daily dose of omega-3s from other sources, such as algae supplements. Algae is the only plant-based source that contains both DHA and EPA fatty acids.

    Some foods, such as certain brands of eggs, dairy products, and juices are fortified with DHA and EPA. Additionally, the omega-3 known as ALA is found in a variety of healthful plant-based sources, such as flaxseeds, chia seeds, walnuts, and vegetable oils. However, the issue with ALA fatty acids is that they are not easily absorbed by the body. The body must convert ALA into DHA and EPA before being absorbed. Thus, the gold standard for obtaining omega-3s is by consuming food sources that contain DHA or EPA or supplementing with fish oils or algae supplements.

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    Dr. Carla Montrond Correia ND, CNS
    Medical Content Manager
    Dr. Montrond-Correia is a licensed naturopathic physician and a certified nutrition specialist (CNS). She holds degrees from University of Bridgeport, Georgetown University, and University of Saint Joseph, and supplemented her education with internships in the health and wellness space. She's focused on research, herbal medicine, nutrigenomics, and integrative and functional medicine. She makes time for exercise, artistic activities, and enjoying delicious food.
    Jordana Tobelem, RD
    Freelance Contributor
    Jordana Tobelem is a Registered Dietitian who enjoys helping others become the best versions of themselves through proper nutrition education. Jordana is passionate about promoting lifestyle changes through nutrition, physical activity, and behavior to create a superior quality of life. She uses her experience in the clinical field of dietetics to provide consulting services to an array of healthcare brands and companies. Jordana loves finding the most current research in nutrition to create meaningful content to share with her clients. Jordana has been a member of the Academy of Nutrition and Dietetics since 2018 and also holds certifications in both Personal Training and Health Coaching.