Breakfast is important – really important – so it's generally a good idea to fit it into your morning. And if you're going to make time for the most important meal of the day, then breakfast cereals can be a good option.

They can be a good source of carbohydrates and fibre, but they can also be high in sugars and salt. So how can you be sure that the cereal you choose doesn't ruin your morning?

Why is breakfast important?

Starting your day with breakfast has its benefits. A number of studies suggest that people who eat breakfast are less likely to be overweight or obese than those who skip it. Eating breakfast can also help children with concentration and performance at school.

Our body's preferred source of fuel is carbohydrates, so to kick-start your day a cereal – being grain-based and therefore naturally high in carbohydrates – is generally a good option. And a cereal high in fibre is a real bonus. Adults need about 25–30g fibre a day, and most of us don't eat enough. And it's not just adults – a recent Australian study found that only 18% of pre-schoolers were getting enough fibre.

You should be able to rely on a breakfast cereal to deliver a decent whack of your daily fibre needs, so we believe fibre content should be one of the top priorities when you're strolling down the cereal aisle. What you don't want in a breakfast cereal is lots of salt, sugar or saturated fat (see our Tips for choosing the right cereal).

Kids' cereals high in sugar and salt

Children don't need as much fibre as adults, but a cereal with a moderate amount of fibre is still better for them than one with little or none. Despite this, many of the cereals aimed at children barely make a dent in meeting their daily fibre needs.

By contrast, it seems there's no shortage of sugar when it comes to kids' cereal. What's perhaps more surprising is that children's cereals can tend to be quite high in salt as well.

Sugar and salt do play a vital role in the tastiness of a product, but many cereals targeted specifically at kids have more in common with treat foods than a nutritious breakfast.

What about porridge and muesli?

It's hard to go past porridge for a good family breakfast – a cup of cooked rolled oats gives you about 4g of fibre, and the only sugar and salt is what you add. For the run-down on muesli, check out our muesli buying guide.

Tips for choosing the right cereal

Compare Health Star Ratings

In the first instance you can look at a product's Health Star Rating (HSR). HSRs have been designed to help you choose healthier options at a glance – essentially the higher the star rating (ratings go from 0.5 stars up to 5 stars), the healthier the option.

The HSR is an assessment of the overall healthiness of a product, taking into consideration the 'bad' nutrients in food, such as sodium, sugars and saturated fat, as well as beneficial nutrients, including fibre and protein. Our breakfast cereal review found plenty of products in the cereal category that achieve 4.5 or even 5 stars, so consider these as your first choice.

n the absence of a star rating, below are our top tips when choosing.

How to pick a healthy breakfast cereal

High fibre. Dietary fibre helps maintain a healthy digestive system and decreases the risk of bowel cancer. In countries with diets high in fibre and wholegrains, diseases such as bowel cancer, diabetes and coronary heart disease are less common. On average, Australians consume 20–25g of fibre daily, although we should be consuming more (25g for women, 30g for men). Choosing a breakfast cereal with a substantial amount of fibre will set you on your way to meeting your daily fibre needs. 7g per serve is considered to be an excellent source of fibre, but manufacturer-recommended serving sizes can vary greatly between brands and products, making it difficult to compare like with like. For a cereal with better-than-average fibre content, look for 10g fibre per 100g or more.

Wholegrains. The words 'whole' or 'wholegrain' in the first ingredient or two usually means the cereal is less processed and will contain more vitamins, minerals and phytochemicals. A diet high in wholegrains and cereal fibre can reduce the risk of premature death from chronic diseases including cancer, cardiovascular disease and diabetes.

What to avoid in breakfast cereal

High sodium (salt). Sodium is linked to high blood pressure and an increased risk of heart disease. Australians consume 2150mg of sodium a day, on average, but the recommended upper level of intake for adults is 2300mg/day (1400mg/day for 4–8-year-olds) and adults only need 460–920mg (children, even less) to meet our body's requirements. Ideally the product you choose should have 400mg sodium per 100g or less. But if salt is of particular concern to you, look for products containing 120mg of sodium per 100g or less, which standards define as 'low sodium'.

High sugar. Kids' cereals in particular are major offenders. In some instances, dried fruit – which can provide fibre, vitamins and minerals – contributes to the total sugars. But frequently the culprit is added sugars, which we should only be consuming in moderation. A good rule of thumb is to look for less than 15g sugar per 100g, allowing a little leeway if the cereal contains dried fruits.

High saturated fat. Breakfast cereals generally aren't high in saturated fat, but watch out for ingredients such as coconut oil or palm oil – often in cluster-type cereals – which can increase saturated fat levels. Products that contain 1.5g or less saturated fat per 100g can be classified 'low in saturated fat' according to food standards.

Navigating marketing spin

Breakfast cereal packets are plastered with a bewildering range of claims designed to catch your eye and choose one product over another. The problem is that claims such as "no artificial colours or flavours", "contains wholegrain", "added vitamin and minerals", "source of fibre" and "99% fat free" are masking a cereal that's fibre-flimsy, contains too much salt, too much sugar or all of the above.

Most cereals have vitamins and minerals added to them, including those that are unhealthy in every other way. Make your shortlist based on the health star rating (or alternatively high fibre and lower salt and sugars) before considering added vitamins and minerals.

A claimed source of fibre/protein/antioxidants doesn't necessarily mean the cereal contains large amounts of these nutrients. The qualifying criteria for claiming a product is a 'source' of dietary fibre is just 2g per serving, for example, and depending on the serving size this may not to amount to much at all. It's best to check the nutrition information panel instead to see how much of a nutrient is actually in the product, rather than rely solely on claims.

Read the ingredients list. It's useful for identifying sources of added sugars (such as glucose syrup or honey) or when the sugar comes from fruit, as well as when the fat is the healthy, polyunsaturated kind (coming from nuts and seeds).

Do I need low-GI breakfast cereal?

A low GI diet can be beneficial if you suffer from diabetes, and may be useful for those watching their weight, but most people are better off prioritising a healthy cereal first before looking for a low-GI option. Any GI claims should be backed up by reliably measured GI values – 55 and under is classified as low. The only way to be certain is to look for the GI logo which means the food must meet specific nutrition criteria as well.