One food is perfect for those who need more protein but want to keep calories low

Tasty, low calorie, protein rich, and cheap - it's tricky to all four boxes, but tuna manages it all the above.

Chock full of belly-filling protein, tuna is a healthy eating superstar. It's beautifully versatile, whether snapped up by the tin for pennies or seared in steak form for a special meal.

And according to Healthline, it's one of the healthiest foods you can eat and a staple of weight loss diets for good reason. The fish comes in at number 32 on the list of 50.

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The website noted: "Tuna tends to be low in fat and calories and high in protein. It’s perfect for people who need to add more protein to their diets but keep calories low."

Why is tuna part of a healthy diet?

Protein, and lots of it

Tuna is a lean meat, which means it's high protein and low calorie. Protein is an important part of our diets that has the added benefit of keeping us fuller for longer due to it taking longer to digest.

Protein is made of amino acids, the chemical building blocks that help build cells and repair old ones. It benefits your body by maintaining muscles and repairing wounds, whilst it's particularly important for growing children and pregnant women.

It's low in calories

Not only does tuna help you feel full, it's low calorie. You'll find the least amount of calories is tinned tuna in brine, which amounts to around 25g of protein but just over 100 calories per 100g.

A serving of the same size of fresh tuna is a bit more caloric at about 130 calories, according to BBC GoodFood, but has more protein (about over 30g).

Both versions have similar amounts of protein and fat.

Tuna is one of the best sources of vitamin D

Vitamin D helps regulate calcium and phosphate which keep bones, teeth and muscles healthy, according to the NHS.

The sun is the primary source of vitamin D, though there is a dearth of it in the UK, particularly in winter. In fact, sun levels are so low that the government advice is for all Brits to take a supplement from October to early March.

That's why it's all the more important to include vitamin D rich foods like tuna, oily fish, red meat and egg yolks.

We should be eating more fish

Regardless of whether you're watching your weight, the NHS says we should be eating more fish as it's an important source of many vitamins and minerals.

Most of us aren't eating enough, according to the health service which recommends a minimum of two 140g portions of fish weekly, including one oily fish. Salmon, trout and sardines are oily fish, but tuna is not.