Standing in the supermarket aisle comparing nutrition panels can feel overwhelming. Numbers, percentages, and unfamiliar terms compete for your attention while you try to figure out which tuna is actually the healthiest choice. The good news is that once you understand what to look for, reading nutrition labels becomes second nature.
This guide walks you through the key elements of a canned tuna nutrition label, explains what the numbers really mean, and helps you identify the products that best match your dietary goals.
Understanding Australian Nutrition Panels
Australian food products use a standardised Nutrition Information Panel (NIP) format. For canned tuna, you'll typically see values presented both per serve and per 100g, making it easier to compare products regardless of can size.
Serving Size
Always check the serving size first. It's listed at the top of the nutrition panel. For canned tuna, serving sizes vary widely—some products use 60g, others 95g, and larger cans might list 150g. If you're comparing products, use the per 100g column for accurate comparisons.
The "per 100g" column is your best friend for comparing products. A tuna with 120mg sodium per 60g serve looks better than one with 200mg per 95g serve—until you realise the first is actually 200mg per 100g while the second is only 211mg per 100g.
Protein: The Star Nutrient
Protein is typically why people eat canned tuna, and it's where this product really shines. Here's what to look for:
What's a Good Protein Level?
- Excellent: 25g+ protein per 100g (tuna in springwater typically hits this)
- Good: 20-25g protein per 100g (most plain tuna products)
- Lower: Under 20g per 100g (often flavoured varieties with added ingredients)
Tuna in springwater generally has the highest protein concentration because you're getting almost pure fish. Oil-packed and flavoured varieties have slightly lower protein percentages because of the added ingredients, but still deliver substantial amounts.
Protein Quality
Beyond quantity, tuna protein is high quality—it's a complete protein containing all essential amino acids your body needs. This makes tuna particularly valuable for muscle building, recovery, and overall health.
Fat Content: Oil vs. Water
Fat content in canned tuna varies dramatically depending on the packing medium:
Tuna in Springwater
Typically contains 0.5-2g total fat per 100g. This is mostly naturally occurring fat from the fish itself and includes beneficial omega-3 fatty acids. It's the leanest option.
Tuna in Oil
Contains 8-15g total fat per 100g when undrained. If you drain the oil, fat content drops significantly—but so does your omega-3 intake, as some of the fish's natural oils leach into the packing oil.
What to Consider
If you're counting calories or following a low-fat diet, tuna in springwater is the obvious choice. However, if you're focused on healthy fats and don't mind the extra calories, oil-packed tuna (especially in olive oil) can be a nutritious option—just be aware of the calorie increase.
- Springwater: ~0.5-2g fat per 100g (lowest calorie option)
- Oil (drained): ~3-5g fat per 100g
- Oil (undrained): ~8-15g fat per 100g
Sodium: The Number to Watch
Sodium is often the nutritional concern with canned foods, and tuna is no exception. Understanding sodium levels helps you make heart-healthy choices.
Sodium Guidelines
The Australian Heart Foundation recommends limiting sodium to 2000mg per day, with a target of 1600mg or less for better health outcomes. Here's how tuna products compare:
- Low sodium: Under 250mg per 100g (look for "reduced salt" or "no added salt" products)
- Moderate sodium: 250-400mg per 100g (most plain tuna products)
- Higher sodium: 400mg+ per 100g (common in flavoured varieties and brine-packed products)
Brine vs. Springwater
Tuna packed in brine (salted water) has significantly higher sodium than tuna in springwater. If sodium is a concern, always choose springwater or specifically "reduced salt" options. Some brands now offer "no added salt" varieties with under 100mg sodium per 100g.
Flavoured tuna products often contain more sodium than plain options. Seasonings, sauces, and flavour enhancers all contribute to higher sodium levels. Always check the panel if you're watching your salt intake.
Carbohydrates and Sugars
Plain canned tuna contains virtually no carbohydrates—typically 0g per serve. This makes it ideal for low-carb, keto, and paleo diets.
Flavoured Products
Where carbs and sugars appear is in flavoured varieties. Sweet chilli tuna, for example, may contain 5-10g of carbohydrates per 100g, with a significant portion from added sugars. Tomato-based products also contain natural and sometimes added sugars.
If you're watching carbs or sugar, check the panel carefully for flavoured products. Plain tuna remains the cleanest option from a carbohydrate perspective.
What's NOT on the Label
Some nutritional information isn't required on Australian labels but may be important to you:
Omega-3 Content
While some brands voluntarily list omega-3 content, it's not mandatory. As a general guide, tuna in springwater contains 200-400mg of omega-3s per 100g, while oil-packed tuna may show higher numbers but some of those omega-3s are lost when you drain the oil.
Mercury Levels
Mercury isn't listed on labels. For this information, you need to rely on general guidelines: skipjack (light) tuna has lower mercury than albacore (white) tuna.
Reading the Ingredients List
Beyond the nutrition panel, the ingredients list tells you exactly what's in the can:
- Plain tuna: Should list only tuna (sometimes with species name), water or oil, and possibly salt
- Flavoured tuna: Will list additional ingredients—shorter lists with recognisable ingredients are generally better
- Watch for: Added sugars, vegetable oils (which can indicate lower-quality oil), and excessive additives
Comparing Products: A Practical Example
Let's compare two hypothetical products (per 100g):
Product A (Tuna in Springwater): Energy 440kJ, Protein 26g, Fat 0.8g, Carbs 0g, Sodium 290mg
Product B (Flavoured Tuna): Energy 520kJ, Protein 19g, Fat 2.5g, Carbs 6g, Sodium 450mg
Product A is the better choice for maximum protein with minimum calories and sodium. Product B might be convenient and tasty, but comes with nutritional trade-offs. Neither is necessarily "bad"—it depends on your priorities and how frequently you're consuming it.
Quick Label-Reading Checklist
- Check serving size and use per 100g for comparisons
- Look for high protein (20g+ per 100g)
- Compare sodium (lower is generally better)
- Consider fat source (springwater for lean, olive oil for healthy fats)
- Check sugars in flavoured products
- Read ingredients for quality indicators
With practice, you'll be able to scan a nutrition label in seconds and identify whether a product meets your dietary needs. The key is knowing which numbers matter most to you and comparing products consistently using the per 100g column.