Is Tuna Good for Weight Loss? We Asked a Dietitian
Key takeaways:
Tuna is a lean, low-calorie protein that may support weight loss by helping you feel full for longer. It also provides vitamins and minerals like iron and vitamin D.
Tuna contains mercury, so it’s not a food you should eat every day. Enjoy it a few times a week. And try to choose lower-mercury tuna types like canned skipjack (light) tuna most often.
Tuna is versatile. Canned tuna is particularly convenient and inexpensive. But you can also enjoy grilled or seared tuna steaks, or raw tuna in sushi or poke bowls.
When you’re eating for weight loss, it helps to include foods that are nutritious, versatile, and tasty. Tuna checks all of these boxes. It’s high in protein and low in calories, and it provides essential vitamins and minerals. Plus, you can buy tuna canned or raw and use it in a variety of delicious ways.
So, if weight loss or weight maintenance is your goal, tuna may be a good food to add to your diet.
Tuna benefits for weight loss
Here are four ways tuna can be a good choice for weight loss.
1. Low in calories
Reducing the amount of calories you consume is one way to lose weight. And studies show that eating fish and seafood in place of meat reduces calorie intake by 4% to 9%. A 3 oz serving of tuna has 90 to 120 calories. The same size serving of beef (T-bone steak) has about 180 calories.
To be clear, cutting calories isn’t the only way to lose weight, but it’s one strategy that may help. For years, the leading advice for weight loss was to eat fewer calories and get more exercise (eat less, move more). But this works for some people and not others. Your healthcare team can help you find the right weight-loss approach for you.
2. High in protein
Protein is an essential nutrient in the diet. And it helps you feel full and stay full for longer, which may help you consume less food overall. Eating enough protein may also help prevent regaining weight after weight loss.
Is protein good for weight loss? Protein can help you lose weight by making you feel full, increasing the amount of calories you burn, and reducing your appetite.
What’s the healthiest fish to eat? All fish is high in protein and low in saturated fat. But some fish — like salmon and sardines — are also high in omega-3 fats, which may support heart health.
How much protein do you need? It can be hard to know how much protein you need, since the recommended amount differs from person to person. Here’s how to calculate your needs.
Studies show that having 25 g to 30 g of protein at meals may help with weight management. Tuna can help you reach this goal, since it has 18 g to 22 g of protein per 3 oz serving. If you add some whole grains and vegetables to round out your meal, it’s easy to reach that 25 g to 30 g protein goal.
3. Low in fat
Tuna is low in fat, especially if you choose canned tuna. Most canned tuna has 0.5 g to 2.5 g of fat per serving (which is less than chicken or turkey breast). Bluefin and ahi tuna steaks have closer to 5 g of fat per serving. Some of the fat in tuna is beneficial omega-3 fat, which is linked to better heart health.
To be clear, dietary fat is essential in the diet. But some people cut back on fat intake when they’re trying to lose weight. That’s because fat has more calories per gram (9) compared to carbohydrates (4) or protein (4). If your weight-loss diet calls for low-fat protein options, tuna can be a great choice.
4. Vitamins and minerals
If you’re on a lower-calorie diet, it’s important to make sure the foods you eat have plenty of nutritional value in every bite. Tuna is a great choice since it contains many essential vitamins and minerals.
Tuna’s vitamins include:
Vitamin B3, which helps turn food into usable energy for the body
Vitamin B6, which supports brain health, the immune system, and the nervous system
Vitamin B12, which helps your body make red blood cells and DNA and protects your nerves
Vitamin D to support bone health
Tuna is a great source of minerals, including:
Iron, to help make red blood cells
Phosphorus, which is vital for healthy bones and teeth
Selenium, which acts as an antioxidant to protect body cells from disease-causing damage
Tuna nutrition facts
“Tuna” is a broad term for about a dozen different types (species) of fish, including:
Albacore
Bigeye
Bluefin
Skipjack
Yellowfin
You may also see ahi tuna on restaurant menus. Ahi is a Hawaiian word for tuna, and it can refer to either yellowfin or bigeye tuna.
Below is nutrition information for different types of tuna per 3 oz. (85 g) serving. Note: A standard can of tuna is 5 oz, and the larger cans are typically 12 oz.
Calories | Protein | Fat | Omega-3 fats (DHA+EPA) | Carbs | |
|---|---|---|---|---|---|
Canned light tuna (skipjack in water) | 99 kcal | 22 g | 0.7 g | 0 g | 0 g |
Canned white tuna (albacore in water) | 109 kcal | 20 g | 2.5 g | 0.75 g | 0 g |
Fresh ahi tuna steak (seared) | 120 kcal | 18 g | 5 g | Not available | 0 g |
122 kcal | 20 g | 4.2 g | 1.1 g | 0 g |
Potential risks of eating tuna
Tuna contains mercury, a natural element found in the air, soil, and water. Being exposed to high levels of mercury over time can be toxic and lead to health issues.
Some types of tuna contain more mercury than others. This is because larger fish that live longer (like albacore) gather more mercury in their bodies than smaller fish (like skipjack).
Usually, people don’t develop mercury toxicity from tuna (or other foods). But, to be safe, the FDA has some guidelines around seafood consumption to help limit mercury exposure. The FDA recommends the following tuna choices:
Best choice: canned skipjack (light) tuna (up to 3 servings or 12 oz per week)
Good choices: albacore white tuna and yellowfin tuna (1 serving per week)
Choice to avoid: bigeye tuna
But it’s important to note that the FDA has different guidelines for children ages 1 to 11 and for those who are pregnant or nursing. That’s because mercury may have a bigger health impact on these people.
How to add tuna to your diet for weight loss
Meals to support weight loss are usually high in protein and fiber and low in calories. Tuna is high in protein and low in calories. But it doesn’t contain fiber. So try pairing tuna with fiber-rich foods like whole grains, vegetables, and beans. Examples of balanced meals include:
Seared tuna steak with broccoli and quinoa
Tuna sandwich on whole-grain bread with tomato, lettuce, and a side salad
Nicoise-style salad using canned tuna on lettuce greens and topped with green beans, potato, and a hard-boiled egg
Tuna poke bowl with edamame, cucumber, and avocado on brown rice
Frequently asked questions
Yes, you can eat tuna raw. Tuna is often served raw in poke bowls, sushi (raw fish and rice), and sashimi (thinly sliced raw fish). But raw tuna can contain parasites, which are killed by cooking or freezing. So, if you’re planning to eat raw tuna, be sure to buy sushi-grade tuna, which has been properly frozen at temperatures low enough to kill any parasites.
Since tuna contains mercury, you shouldn’t eat it every day. The Dietary Guidelines for Americans recommends eating 8 oz of fish per week (typically in 2 to 3 servings). You can choose tuna or any other fish.
But it’s best to eat a variety of fish and seafood to avoid excessive mercury from one species of fish. Salmon and sardines are examples of two healthy, lower-mercury fish worth adding to your rotation.
Canned tuna is good for you. It’s high in protein, vitamins, and minerals. Canned white (albacore) tuna has more calories and beneficial omega-3 fat than canned skipjack (light) tuna. But it’s also higher in mercury. Enjoy both varieties on rotation.
The bottom line
Tuna is a relatively low-calorie and low-fat source of protein, vitamins, and minerals. This makes it a good choice for overall health or for anyone with a goal of weight loss or weight management. Choose lower-mercury types of tuna like skipjack, and avoid high-mercury tuna such as bigeye. Try tuna flaked on salads, raw in sushi or poke bowls (if it’s sushi grade), or seared on the barbeque for a delicious, filling meal.
Why trust our experts?
References
Hawaii Seafood. (n.d.). Yellowfin tuna (ahi).
International Seafood Sustainability Foundation. (n.d.). Tuna species.
Kim, J. Y. (2020). Optimal diet strategies for weight loss and weight loss maintenance. Journal of Obesity & Metabolic Syndrome.
Leidy, H. J., et al. (2015). The role of protein in weight loss and maintenance. The American Journal of Clinical Nutrition.
Liaset, B., et al. (2019). Seafood intake and the development of obesity, insulin resistance and Type 2 diabetes. Nutrition Research Reviews.
Moon, J., et al. (2020). Clinical evidence and mechanisms of high-protein diet-induced weight loss. Journal of Obesity & Metabolic Syndrome.
MyFoodData. (n.d.). Bumble Bee Foods LLC - Bumble Bee super fresh seared ahi tuna.
MyFoodData. (n.d.). Canned white tuna (water packed).
MyFoodData. (n.d.). Fish, tuna, light, canned in water, without salt, drained solids.
MyFoodData. (n.d.). Grilled T-bone steak.
MyFoodData. (n.d.). Raw bluefin tuna.
Office of Dietary Supplements. (2023). Phosphorus: Fact sheet for health professionals. National Institutes of Health.
Office of Dietary Supplements. (2024). Iron: Fact sheet for health professionals. National Institutes of Health.
Office of Dietary Supplements. (2024). Omega-3 fatty acids: Fact sheet for health professionals. National Institutes of Health.
Office of Dietary Supplements. (2024). Selenium: Fact sheet for consumers. National Institutes of Health.
U.S. Department of Agriculture. (2020). Dietary guidelines for Americans 2020-2025.
U.S. Food and Drug Administration. (2021). Advice about eating fish: For those who might become or are pregnant or breastfeeding and children ages 1 – 11 years.
U.S. Food and Drug Administration. (2021). Questions & answers from the FDA/EPA advice about eating fish for those who might become or are pregnant or breastfeeding and children ages 1 to 11 years.
