What 100g of tuna typically contains

For plain tuna, 100g is usually around 110–130 calories when it’s canned in water, though oil-packed tuna can be significantly higher. Protein is the standout nutrient: 100g often provides about 23–29g of protein, making tuna one of the most protein-dense foods you can eat.

Tuna is also naturally low in carbohydrates and contains little fat unless it’s packed in oil or a fattier cut is used. It can provide important micronutrients such as selenium, vitamin B12, niacin, and sometimes vitamin D and omega-3 fats, depending on the species.

Why 100g of tuna is popular for fitness and meal planning

Because it delivers a lot of protein for relatively few calories, 100g of tuna is useful for building meals that support muscle repair, satiety, and weight management. It’s easy to portion into salads, rice bowls, sandwiches, pasta, and wraps.

If you track your nutrition, tuna can be especially convenient because the serving size is simple and consistent. For home workouts, Fitnit can also help you keep training efficient with automatic rep counting and AI-powered form analysis, which is useful when you’re trying to pair a high-protein diet with a steady exercise routine.

Tuna quality, sodium, and mercury: what to watch

Not all tuna is nutritionally identical. Light tuna is generally lower in mercury than albacore or bigeye tuna, and fresh tuna steaks can differ from canned products in fat and sodium content. If the tuna is canned in brine or seasoned, sodium may be much higher than plain tuna.

Mercury matters most if you eat tuna often. The FDA and EPA recommend choosing lower-mercury seafood more often and limiting higher-mercury fish, especially for pregnant people, children, and anyone eating seafood frequently. Variety is a smart strategy: rotate tuna with salmon, sardines, trout, beans, eggs, chicken, or tofu.

How to use 100g of tuna in real meals

A 100g portion is enough for a single protein serving in many meals. Mix it with Greek yogurt or olive oil mayonnaise for a sandwich filling, toss it with beans and vegetables for a salad, or pair it with whole grains and avocado for a balanced bowl.

For best results, combine tuna with fiber-rich foods such as vegetables, fruit, legumes, or whole grains. That helps round out the meal nutritionally and can make it more filling than tuna alone.

Tips

• Check the label: canned tuna in water is usually lower in calories than tuna packed in oil.
• Watch sodium if you eat canned tuna often, especially versions with added flavoring or brine.
• Choose light tuna more often if you want to reduce mercury exposure.
• Pair tuna with vegetables and whole grains to make the meal more filling and balanced.
• Use a food scale if you want to track 100g portions accurately.