Nutrients and Benefits of Eating Swordfish

Swordfish is a large predatory fish that is consumed by many people. It is the fastest known fish in the ocean.

The characteristic sword-like bill gives it the name.

Consuming it in large amounts can lead to mercury toxicity.⁽¹⁾

There are numerous essential nutrients present in swordfish.

Essential nutrients are those that can be obtained from food. They are not made in the body.

3 oz serving of swordfish provides:⁽²⁾

• 146 calories
• 20 grams protein
• 6.7 grams fat
• No carbs
• 106% of the daily value of selenium
• 71% of the daily value of vitamin D
• 9% of the daily value of potassium
• 7% of the daily value of magnesium

Swordfish is high in selenium, a trace mineral that is important for human health. Selenium plays a role in thyroid and bone metabolism, heart health, immunity, and male fertility.^(3,4)

Swordfish is also a good source of vitamin D, a vitamin that is beneficial for immunity, heart health and asthma.⁽⁵⁾

Also, swordfish contain a high amount of omega-3 fatty acids that are known to protect against heart and inflammatory diseases. It also improves heart health.^{(6, 7)}

Due to their rich nutrient content, swordfish are known to serve humans with numerous health benefits.

High cholesterol levels and high blood pressure increase the risk of heart disease.

Omega-3 fatty acids present in swordfish improve cholesterol and blood pressure levels, especially in people with pre-existing heart conditions.⁽⁸⁾ They improve the blood vessel function and elasticity and lower the blood pressure.

They also lower the blood triglyceride levels and prevents blood clot formation and clogging in the arteries.⁽⁹⁾

Additionally, vitamin D in swordfish lowers blood pressure and the risk of a heart attack. A study found people with low vitamin D levels are at a higher risk of suffering from heart disease. ^{(10, 11)}

Evidence suggests, taking vitamin D supplements lowers systolic blood pressure by 2-6 mm Hg. It does so by interacting with multiple systems in the body including the kidney and endocrine system.⁽¹²⁾

Swordfish can help protect against cancer due to the nutrients omega-3, vitamin D, and selenium present in it.

Omega-3s and vitamin D have anti-inflammatory properties and play a role in reducing inflammation that is a predisposing factor for cancer. Studies show both these nutrients protect against colorectal cancer.^(10,11)

These nutrients prevent cancerous cells from reproducing and inducing their death. Vitamin D also stops the growth of new blood vessels that feed these cells.

Omega-3s prevent cancer cell metastasis.

Selenium present in swordfish is a powerful antioxidant that fights with free radicals in the body and protects against liver, prostate, breast, and lung cancer.^(12,13) It also improves the quality of life in people undergoing radiotherapy.

Vitamin D is known to protect bone health. It stimulates calcium absorption in the gut.

Deficiency of vitamin D is linked with bone loss and an increased risk of fractures.^(14,15)

Selenium also plays a role in improving bone health. It maintains a balance by inactivating osteoclast to prevent brittle bones.⁽¹⁶⁾

Apart from all the benefits it serves, swordfish comes with an important drawback due to its high mercury content.

Mercury comes from the water and coal burning and ends up in lakes and oceans from rainwater. Aquatic organisms absorb it and are further absorbed by large predators when they eat these organisms.

This results in mercury moving up the food chain from prey to predator. Larger, longer-living predator, higher is the quantity of mercury in them.⁽¹⁷⁾

Mercury affects the brain and is known as a neurotoxin. It may even diminish the beneficial effect of omega-3s on the heart.^(18,19)

Mercury can also cross the placenta or be passed to the babies through breast milk. It can be dangerous for the development of the nervous system in babies.^(20,21)

Swordfish is a popular fish that is rich in omega-3s, selenium, and vitamin D. All these nutrients are beneficial for health. It can be enjoyed by grilling, stewing, or boiling.