High blood pressure, also known as hypertension, is a serious medical condition that can increase the risk of heart disease, stroke, and other health problems. Diet and lifestyle choices can have a significant impact on blood pressure. For those looking to lower their blood pressure, it’s important to understand which foods may contribute to hypertension.
Does seafood raise blood pressure?
Some types of seafood are high in sodium, which can cause an increase in blood pressure. However, other types of seafood provide heart-healthy omega-3 fatty acids that can help reduce blood pressure. The impact of seafood on blood pressure depends on the specific variety.
High-sodium seafood
The following types of seafood are known to be high in sodium:
- Canned tuna, sardines, and anchovies
- Salt-cured fish like cod, haddock, and salmon
- Dried and salted fish
- Caviar
- Smoked fish and seafood
- Salted shellfish like oysters, shrimp, and clams
- Canned shellfish including clams, mussels, crab, and lobster
Sodium causes the body to retain water, which increases the volume of blood and leads to higher pressure on artery walls. The Dietary Guidelines for Americans recommend limiting sodium to less than 2,300 milligrams per day. However, those with high blood pressure may need to restrict sodium to 1,500 mg or less daily.
Just 3 ounces of canned tuna can contain over 500 mg of sodium. Heavily salted seafood like smoked salmon, cod, and caviar also pack a sodium punch. To reduce blood pressure, it’s best to limit intake of these high-sodium seafood options.
Low-sodium seafood
Many types of fresh and lightly seasoned seafood are relatively low in sodium. These include:
- Fresh fish like salmon, cod, halibut, and tuna
- Fresh shellfish including shrimp, crab, lobster, clams, mussels, and oysters
- Lightly seasoned grilled, baked, or broiled seafood
- Sashimi and poke made from fresh raw fish
Choosing fresh or frozen seafood and preparing it yourself with minimal added salt allows you to control the sodium content. Canned seafood labeled “low sodium” can also help reduce salt intake.
Omega-3 rich seafood
Seafood high in omega-3 fatty acids may help lower blood pressure. Omega-3s reduce inflammation and have a mild blood thinning effect, both of which can support healthy blood pressure levels. The best sources of omega-3s in seafood include:
- Salmon
- Mackerel
- Herring
- Sardines
- Trout
- Oysters
Aim for at least two servings per week of these omega-3 rich fish. Grilling, baking, or broiling is best to avoid adding extra fat.
Summary of seafood and blood pressure
To summarize, here are some general guidelines around seafood and blood pressure:
- Limit high-sodium seafood like canned, salted, smoked, and dried fish and shellfish
- Enjoy fresh seafood prepared with minimal salt
- Eat more omega-3 rich fatty fish like salmon and tuna
- Read nutrition labels to keep sodium in check
- Discuss your diet with your doctor to understand blood pressure management
Studies on seafood and blood pressure
Numerous studies have analyzed the impacts of seafood consumption on blood pressure:
High-sodium seafood
A meta-analysis in the American Journal of Hypertension looked at 133 clinical trials. Researchers found that reducing sodium intake by an average of 1,150 mg per day lowered systolic blood pressure by 3.7 mmHg. Diets higher in sodium were associated with increased blood pressure.
A study in JAMA Internal Medicine followed adults over 16 years. Higher sodium intake from foods like processed meats, pizza, and seafood was linked with a greater risk of elevated blood pressure.
Low-sodium seafood
A study in the journal Hypertension followed middle-aged adults for over a decade. Replacing one serving per day of red meat with low-sodium fish significantly lowered systolic blood pressure.
Research in Nutrients had patients follow the DASH diet, which emphasizes fruits, vegetables, lean proteins like seafood, and low-fat dairy. After 8 weeks, participants lowered their systolic blood pressure by 5.5 mmHg.
Omega-3 rich seafood
A systematic review in the Journal of Hypertension evaluated 70 trials on omega-3 fatty acids from seafood and fish oil supplements. Total analysis found that omega-3s reduced systolic blood pressure by 1.7 mmHg and diastolic by 0.9 mmHg.
A meta-analysis in the American Journal of Hypertension assessed 17 clinical trials on omega-3s. Higher intake was associated with lower blood pressure in both healthy and hypertensive individuals.
| Study | Key Finding |
|---|---|
| American Journal of Hypertension meta-analysis | Reducing sodium by 1,150 mg/day lowered systolic BP by 3.7 mmHg |
| JAMA Internal Medicine cohort study | Higher sodium intake linked to greater risk of elevated BP |
| Hypertension diet study | Replacing red meat with fish lowered systolic BP |
| Nutrients DASH diet study | DASH diet with seafood lowered systolic BP by 5.5 mmHg |
| Journal of Hypertension omega-3 review | Omega-3s reduced systolic BP by 1.7 mmHg |
Tips for managing blood pressure with diet
The best dietary approach for managing blood pressure will depend on your individual health profile. Here are some tips that may help:
Limit sodium
Reduce intake of high-sodium foods like canned soups, chips, deli meats, and fast foods. Read nutrition labels to keep total sodium under 2,300 mg daily, or 1,500 mg if you already have hypertension.
Eat more potassium-rich foods
Potassium helps balance excess sodium and relaxes blood vessels. Good sources include leafy greens, bananas, potatoes, beans, yogurt, fish, and avocados.
Increase dietary magnesium
Magnesium helps regulate blood pressure. Get more from nuts, seeds, dark leafy greens, beans, fish, avocados, yogurt, and dark chocolate.
Load up on vegetables and fruits
Produce is rich in blood pressure-friendly nutrients like potassium, magnesium, and fiber. Aim for 8-10 servings per day.
Choose whole grains
Swap refined grains for fiber-rich whole grains like oats, quinoa, brown rice, barley, and buckwheat.
Limit alcohol
Drinking more than moderate amounts of alcohol can raise blood pressure. Limit intake to no more than 1 drink per day for women, 2 for men.
Maintain a healthy weight
Excess weight strains the heart and impacts blood pressure. Losing just 10 lbs can help lower elevated numbers.
Exercise regularly
Aim for 150 minutes per week of moderate activity like brisk walking. Strength training is also beneficial.
Don’t smoke
Smoking damages blood vessels and causes spikes in blood pressure. Quitting can quickly improve numbers.
Foods that lower blood pressure
Emphasizing foods that have a positive effect on blood pressure is key. Here are some of the top blood pressure-friendly foods to include in your diet:
- Leafy greens like spinach, kale, and collards
- Berries like blueberries, strawberries, and raspberries
- Bananas
- Sweet potatoes
- Beans and lentils
- Nuts like almonds, walnuts, and pistachios
- Seeds like flax, chia, and pumpkin
- Fatty fish high in omega-3s
- Tomatoes
- Olive oil
- Whole grains like oats, quinoa, and buckwheat
- Low-fat dairy products
- Dark chocolate
- Garlic
- Hibiscus tea
Focus on incorporating more of these foods into a varied, nutritious diet to maximize their blood pressure benefits.
Sample meal plan
Here is a sample one day meal plan featuring foods that help control blood pressure:
Breakfast:
- 1 cup oatmeal cooked with low-fat milk, topped with 1/2 cup blueberries and 1 tbsp chopped walnuts
- 1 cup low-fat plain Greek yogurt
- 1/2 grapefruit
- 1 cup green tea
Lunch:
- Tuna salad sandwich on 2 slices whole grain bread with lettuce, tomato, avocado
- 1 cup vegetable soup
- 1 medium orange
- 1 cup unsweetened iced tea
Dinner:
- 4 oz grilled salmon
- 1 cup roasted Brussels sprouts
- 1/2 cup quinoa
- Tossed salad with 2 cups mixed greens, tomatoes, cucumbers, 1 tbsp olive oil lemon dressing
Snacks:
- 1 oz unsalted almonds
- 1 small apple
- 1 oz dark chocolate (70% cocoa)
Conclusion
Some varieties of seafood like canned and salt-cured fish can contribute to high blood pressure due to their high sodium content. However, eating ample amounts of fresh fish and shellfish prepared with minimal salt may have benefits thanks to omega-3 fatty acids. For ideal blood pressure control, limit sodium intake and emphasize nutrient-dense fruits, vegetables, whole grains, nuts, seeds, and healthy proteins like fatty fish. Work with your doctor for personalized dietary recommendations to improve your numbers.