Is Swordfish Healthy? Nutrition, Health Benefits, and Risks

Swordfish is a large predatory fish low in calories and very high in essential nutrients, such as selenium, vitamin D, and vitamin E. Swordfish can benefit heart health, bone health, mood, immune system, and much more. However, consuming too much swordfish can lead to toxic effects, including mercury poisoning.

Are you looking for a healthy fish that is safe to add to your diet? Are you wondering if you can eat fish for weight loss?

Swordfish is a fish packed with nutrition but can also lead to mercury toxicity if consumed in excess. Keep reading to learn how to reap the benefits of swordfish in your diet safely.

What Are the Health Benefits of Swordfish?

Swordfish is a large predatory fish full of essential nutrients, each with its own benefits to human health and well-being, from bone health to immunity to mood and more.

Improving bone health

Swordfish is a great source of vitamin D and selenium, which help improve bone health. Vitamin D is a micronutrient that works together with calcium in the diet, often found in dairy.

These micronutrients support bone health by preventing the release of a hormone that can cause bones to become weaker and break down, called osteoporosis (Johns Hopkins Medicine). When someone has fragile bones, they are much more likely to fracture and break.

According to the USDA, swordfish contains 13.9 micrograms (or 558 international units) of vitamin D per 100g serving.

The Recommended Daily Allowance, or RDA, of vitamin D is 15 micrograms (or 600 international units).

Therefore, a 100g serving of swordfish contains practically your entire daily value of vitamin D.

Prevents heart disease

Swordfish also contains a mineral called selenium. According to the National Institutes of Health, selenium plays a role in heart disease prevention through multiple different mechanisms.

Selenium can help reduce arterial inflammation, therefore lowering blood pressure. In addition, omega-3 fatty acids have been shown to reduce inflammation, which can help lower blood pressure as well.

Similarly, selenium and omega-3s contribute to a lower risk of blood platelets forming together inside a blood vessel, which has the potential to cause blockage and, therefore, a heart attack or stroke.

Selenium is very plentiful in swordfish at a whopping 57.4 micrograms. The daily value recommendation for male or non-pregnant female individuals aged 19 and up is 55mcg. So, once again, getting the entire recommended amount of selenium from a 100g serving of swordfish.

Reduces the risk of cancer

According to the Memorial Sloan Kettering Cancer Center, early research suggests that omega-3 fatty acids can reduce the risk of certain cancers, including colon cancer and colorectal cancer. In addition, fish oil may also reduce the risk of breast cancer.

Selenium also has been known to reduce the risk of developing certain types of cancer, including bladder, stomach, and skin cancer (National Institutes of Health). One of the ways scientists believe this occurs is through DNA repair.

However, research on selenium, omega-3s, and cancer risk continues to emerge, and more evidence is needed to confirm these conclusions.

Boosts your mood

According to Harvard University Medical School, omega-3s (present in swordfish) can boost your mood through multiple possible mechanisms.

Two specific omega-3s that are thought to improve mood are EPA (eicosapentaenoic acid) and DHA (docosahexaenoic acid), both found in fatty fish.

It is proposed that omega-3 fatty acids can travel through the blood-brain barrier and interact with the molecules in the brain that influence mood. Additionally, omega-3 fatty acids reduce inflammation, which has been shown to reduce depression.

However, while scientists see a correlation between omega-3 fatty acids and improved mood, more studies are needed to confirm exactly how this relationship occurs.

Boosts immune system

As previously mentioned, swordfish contains selenium which is also an antioxidant. Antioxidants are compounds naturally present in some foods that protect cells against compounds called free radicals.

Free radicals are naturally produced from the breakdown of foods and other essential processes.

The free radicals can damage cells, DNA, and other atomic structure parts. When there is a balance of free radicals and antioxidants, the immune system can function at its peak.

Is Swordfish Good for Weight Loss?

Swordfish is good for losing weight because it has no carbohydrates. Carbohydrates are human’s primary energy source and are often found in starches, grains, fruits, and dairy.

While we need carbohydrates to survive, when too many carbohydrates are consumed, and not enough are used for energy, the excess carbohydrates are converted into fat.

Over time, this excess fat can build up and contribute to gaining several pounds or even the development of overweight or obesity. When a person is overweight or obese, it dramatically increases the likelihood of developing chronic diseases such as heart disease, high blood pressure, and type 2 diabetes.

Therefore, swordfish is a great low-carbohydrate option for losing weight.

Additionally, swordfish is full of protein and healthy fats (unsaturated fat), which are known to increase satiety or satisfaction. Therefore, you will feel full after eating it and be less likely to overeat later – this may also aid in losing weight.

Is Swordfish Safe to Eat?

While swordfish is rich in flavor, nutrients, and health benefits, it is also a fish very rich in mercury since it is higher up in the food chain. Swordfish has more mercury content than most other fish and seafood, such as Atlantic mackerel or salmon, which are low in mercury.

Mercury gets into the fish people consume through industrial pollution. This pollution contains high concentrations of mercury, which begin in the air and eventually can get into the water sources, such as streams, lakes, and oceans. After that, the mercury is eaten by small aquatic organisms and eventually builds up to a significant amount in the swordfish species.

Due to the very high mercury concentration, the Food and Drug Administration (FDA) and the Environmental Protection Agency (EPA) recommend that the following populations avoid eating swordfish altogether: pregnant women, women who may get pregnant, breastfeeding women, and children under the age of 12.

All other individuals should consume swordfish no more than twice a month.

According to the University of Maine Sea Grant Seafood Guide, when buying swordfish, make sure raw swordfish has a spiral pattern in the flesh, is firm, and without discolored or dull skin. If the fresh fish is cut, it should be smooth and shiny. The color of the meat will vary but should turn tan or beige when cooked.

Nutrition Facts

From calories, protein, and fatty acids, down to vitamins and minerals, let’s learn more about the nutritional benefits of swordfish.

Nutrition table (per 100g)

Calories/Nutrient	Amount
Calories (kcal)	144
Net Carbs (g)	0
Fiber (g)	0
Sugar (g)	0
Fats (Total)	6.65
Protein (g)	19.7
Cholesterol (mg)	66

High in vitamins and minerals

Based on the U.S. Department of Agriculture’s (USDA) FoodData Central food database, swordfish is rich in many vitamins and minerals that help the body function properly. Let’s discuss the key players.

Potassium is a mineral also found in bananas and potatoes. Potassium regulates the heartbeat and manages nerve and muscle functioning. Swordfish contains 418 milligrams of potassium, and the daily value, or DV, is 4,700 milligrams daily.

As mentioned previously, selenium is an antioxidant that functions in heart health, cancer prevention, immune health, etc. Swordfish is very rich in selenium, providing over the recommended daily amount in a 100g serving.

Vitamin D is a vitamin that works with calcium to strengthen the bones and teeth. Calcium and vitamin D prevent the weakening of bones that occurs from a release of hormones from the parathyroid gland. As a result, strong bones are less likely to fracture or break.

Vitamin E is an antioxidant that protects cells against harmful free radicals naturally produced in the human body. A healthy balance of antioxidants in the diet and free radicals helps boost immune functioning and reduce inflammation.

High in protein

Swordfish is very high in protein, with almost 20 grams of protein per 100g serving.

Protein plays a crucial role in each system, from the muscular system to the immune system to the cardiovascular system. Overall, protein is an essential nutrient the body needs for growth and muscle maintenance.

Additionally, since the protein from swordfish comes from an animal protein source, the amino acids are more “bioavailable” when compared to that of plant protein sources. With an increased bioavailability in amino acids, the body can better absorb and eventually use the protein from seafood intake.

Low in fats and calories

Swordfish is a fish species exceptionally high in fat but only has 144 calories per 100g serving. The low number of calories is partially due to its low carbohydrate profile. In fact, it has no carbohydrates at all.

Low-calorie and low-carbohydrate protein sources such as swordfish can help build muscle without gaining excess weight. When paired with a fiber-rich source, swordfish can be a part of the perfect hunger-crushing combo.

High in cholesterol

Swordfish contains 66 milligrams of cholesterol per 100g serving and therefore is a high cholesterol food. For reference, a healthy adult should consume no more than 300 milligrams of cholesterol per day.

Also, the recommendation from the 2020–2025 Dietary Guidelines for Americans is to consume as little dietary cholesterol as possible.

Conclusion

It is recommended only to consume swordfish twice a month to prevent mercury toxicity. Other seafood is lower in mercury content and has a lower risk of mercury toxicity. In salmon, for example, the amount of mercury drops significantly and is safer to consume more often.

Swordfish can be safely consumed in appropriate amounts but should be avoided entirely by specific populations.