How Often Should You Eat Fish a Week?

October 25, 2025 •

3 min read

According to the American Heart Association, incorporating fish into your diet at least twice a week can significantly reduce the risk of heart attack and stroke. Knowing how often should you eat fish a week, however, depends on various factors, including the type of fish you choose and individual health considerations like pregnancy.

Quick Summary

Health authorities recommend aiming for at least two servings of fish per week, including one oily fish, to reap optimal health benefits like omega-3 fatty acids. Individual factors and mercury levels in certain species necessitate specific guidelines, especially for pregnant women and children. This guide provides comprehensive advice on safe consumption.

Key Points

Two Servings Weekly: Aim for at least two portions of fish per week for heart and brain health, with one being an oily variety.
Prioritize Oily Fish: Include fish like salmon, sardines, and mackerel for their high levels of beneficial omega-3 fatty acids.
Watch Mercury Levels: Larger, predatory fish such as shark, swordfish, and bigeye tuna have high mercury and should be limited or avoided by certain groups.
Special Population Advice: Pregnant women, breastfeeding women, and young children should follow stricter guidelines by choosing low-mercury options and limiting intake.
Variety is Vital: Eating a diverse range of fish helps balance nutrient intake and minimizes the risk of accumulating specific contaminants.
Healthy Cooking Methods: Opt for grilling, baking, or steaming over frying to maximize nutritional value and avoid unhealthy added fats.

General Guidelines: The Twice-a-Week Rule

For most healthy adults, the consensus among major health organizations, such as the American Heart Association and the NHS, is to eat at least two portions of fish per week. A portion is typically defined as 140g (about 4.9 oz) cooked. The recommendation specifically includes at least one serving of oily fish to maximize the intake of heart-healthy omega-3 fatty acids. Omega-3s, particularly EPA and DHA, are crucial for brain function and cardiovascular health, and the human body does not produce them in sufficient quantities, making dietary intake essential.

The Importance of Variety

While aiming for two servings is a good starting point, variety is key to both nutrition and mitigating risks. By rotating the types of fish you consume, you can ensure a broader range of nutrients while also minimizing exposure to potential contaminants like mercury. Low-mercury 'Best Choices' from the FDA include salmon, sardines, and tilapia, which can be eaten more frequently.

Fish Consumption Guidelines for Specific Groups

Consumption advice varies for different populations based on potential risks, most notably mercury exposure. Larger, longer-living fish tend to accumulate higher levels of mercury, which can be particularly harmful to a developing brain.

For pregnant and breastfeeding women: The FDA and EPA advise 8 to 12 ounces (2 to 3 servings) per week of a variety of fish lower in mercury. Higher mercury options like king mackerel, shark, swordfish, and bigeye tuna should be avoided entirely.
For children: Parents and caregivers should aim for two servings per week from the 'Best Choices' list, with smaller portion sizes appropriate for the child's age. High-mercury fish should be strictly avoided.
For men and postmenopausal women: These groups have more flexibility and can safely consume a wider variety of fish, but moderation with higher-mercury species is still wise.

The Health Benefits of Regular Fish Consumption

Eating fish regularly provides a wide array of health benefits beyond just omega-3s. It's a great source of lean protein, which is vital for muscle repair and growth. Fish also provides essential vitamins and minerals, including:

Vitamin D and B2 (riboflavin): Important for bone health and energy production.
Calcium and Phosphorus: Support strong bones and teeth.
Iron, Zinc, and Iodine: Crucial for blood health, immune function, and metabolism.

The Risks of Eating Fish

While the benefits generally outweigh the risks for most people, it's important to be aware of the potential drawbacks.

Mercury Exposure: High levels of mercury, a neurotoxin, are the primary concern with overconsumption of certain fish. This is why selecting low-mercury fish and varying your intake is recommended.
Food Poisoning: Improper handling or undercooking, especially with raw shellfish, can pose a risk of bacteria and parasites. Cooking fish thoroughly eliminates most risks.
Excess Omega-3s: In very high amounts, omega-3s can thin the blood, which could be a concern for individuals on blood-thinning medication.

Comparison of Fish Types by Mercury and Omega-3 Content


Fish Type	Mercury Level	Omega-3 Content	Consumption Recommendation	Best Choices for Frequent Eating
Oily/Fatty Fish	Low to Moderate	High	At least one portion per week, up to two for pregnant women/girls.	Salmon, Sardines, Mackerel
White Fish (Low Mercury)	Very Low	Low	Unlimited portions generally safe, but should be varied with oily fish.	Cod, Haddock, Tilapia
White Fish (High Mercury)	Moderate to High	Variable	Limit portions for general population; limit for pregnant women.	Sea Bass, Halibut, Turbot
High-Mercury Fish	High	Variable	Limit to one portion per week for most adults; avoid for pregnant women and children.	Swordfish, Shark, Marlin, Bigeye Tuna

Conclusion

Eating fish twice a week is a well-supported and highly recommended practice for most individuals, offering significant health benefits, particularly for cardiovascular and brain health. However, it's crucial to be mindful of the type of fish consumed to minimize exposure to mercury and other potential contaminants. Adopting a varied diet that includes low-mercury options, especially for vulnerable populations like pregnant women and children, ensures that the nutritional rewards outweigh the risks. By following these guidelines, you can make informed choices to include fish as a healthy and delicious part of your weekly meal plan.

Frequently Asked Questions

For most healthy adults, eating fish every day is generally safe, provided you choose low-mercury species like salmon or sardines and maintain variety. However, for vulnerable groups like pregnant women and children, daily intake is not recommended due to mercury concerns.

A typical adult serving of fish is about 4 ounces (113 grams) measured before cooking, or roughly the size of an adult's palm. Health authorities suggest 2 to 3 servings per week for optimal benefits.

Excellent low-mercury choices include salmon, sardines, cod, haddock, tilapia, and canned light tuna. These fish can be consumed more frequently as part of a healthy diet.

It is best to limit or avoid fish with high mercury levels, such as shark, swordfish, king mackerel, bigeye tuna, and orange roughy.

While supplements can provide omega-3s, eating fish offers a broader range of nutrients, including lean protein, vitamin D, and various minerals. Most experts agree that the benefits of whole foods are superior to supplements.

Fried fish, especially when deep-fried or battered, adds unnecessary calories and unhealthy fats. To get the most health benefits, choose healthier cooking methods like baking, grilling, steaming, or pan-searing with healthy oils.

Pregnant women should consume 8 to 12 ounces per week of fish from the 'Best Choices' list (low in mercury) and completely avoid the 'Choices to Avoid' list. Cooking fish thoroughly is also crucial to reduce the risk of foodborne illness.