Is Porridge Good for Weight Loss?

Clinically reviewed by Associate Professor Christopher O’Donnell, Nurse Practitioner, FACN · Founder and Clinical Director · AHPRA NMW0001453715 · Last reviewed 17 October 2026

Yes, porridge can be a good, healthy breakfast if you’re trying to lose weight. Oats are a wholegrain and contain a soluble fibre called beta-glucan, which can help you feel full for longer. But oats aren’t a weight-loss food on their own: the portion, what you cook them in and what goes on top matter as much as the oats. Below, we cover the health benefits of eating oats, which type to choose, how much to eat and how toppings change the kilojoules.

What are the health benefits of eating oats?

Forty grams of plain rolled oats, about half a cup dry, provides around 630 kJ (150 Calories) and roughly 5 g of protein, according to Australia’s food composition data.

The main point of interest is beta-glucan. This soluble fibre thickens into a gel in the gut, which slows digestion and the absorption of nutrients. Reviews of the research suggest that oat beta-glucan generally increases feelings of fullness, although results vary between studies. Australia’s dietary guidelines note that high-fibre wholegrain foods take longer to digest and can help people feel full.

What does that mean for weight? In a 2022 meta-analysis of randomised trials, adding oats to the diet was associated with small improvements in body weight and waist size, alongside lower LDL cholesterol levels. The effects were modest and many trials had some risk of bias. Porridge can support a weight-loss plan, but it won’t drive one. That’s why a so-called porridge diet isn’t the answer: porridge works as one part of a healthy diet, not the whole plan.

Oats also contribute to your daily fibre intake, which matters for gut health and bowel regularity. Our article on fibre and weight covers this in more detail.

Is porridge fattening?

No. No single food is fattening on its own: weight changes with your total intake over time. A plain bowl of porridge made from 40 g of rolled oats cooked in water comes to about 630 kJ (150 Calories), which is modest for a breakfast that also provides wholegrain fibre and some protein.

Not all porridge is equal, though. What makes porridge energy-dense is the portion and what goes in it. Free-poured bowls, full-cream (full-fat) milk, honey, maple syrup, brown sugar, nut butter and nuts can more than triple the kilojoules of the same oats, as the toppings section below shows. Plain porridge in a measured portion suits a weight-loss plan well.

Rolled, steel-cut or instant oats: does the type matter?

All three start as whole oats. The difference is how they are cut, flattened and cooked.

• Steel-cut oats are whole oat grains chopped into pieces. They are chewy and have the longest cooking time, often 20–30 minutes on the stove
• Rolled oats, the traditional porridge oats, are steamed and flattened, and cook in a few minutes to a creamy consistency
• Quick or instant oats are rolled thinner or cut finer, and instant oats are often pre-cooked, so they cook faster or only need hot water

Plain versions are similar in nutritional value: kilojoules, protein and fibre per gram. The main differences are texture, cooking time and the speed of digestion. International glycaemic index tables show that cereal foods vary widely depending on how they are manufactured, and thinner, more processed oats generally raise blood glucose (blood sugar) more than thicker rolled or steel-cut oats.

The bigger issue is flavoured instant porridge sachets, which often contain added sugar and flavourings. Check the ingredients list and the sugars per 100 g, or buy plain porridge oats and add extra flavour yourself with fruit or spices.

Getting the portion right

Australia’s dietary guidelines count half a cup (120 g) of cooked porridge as one serve of grain foods, providing about 500 kJ. A typical bowl of porridge made from 40 g of dry oats is a little more than one serve.

Weighing your dry oats for a week or two is the simplest way to calibrate your eye, because free-poured bowls are often bigger than they look.

Porridge toppings: how they change the kilojoules

Two bowls of porridge can differ by more than 1,500 kJ depending on what goes in and on them. Approximate figures from Australian food composition data:

• Cooking liquid. Half a cup (125 mL) of skim milk is about 190 kJ, reduced-fat (1%) milk about 230 kJ, regular cow’s milk about 340 kJ and unsweetened almond drink about 80 kJ. Water adds none. Other plant drinks, such as oat milk, vary, so check the label
• Fresh or frozen fruit. Half a cup of frozen blueberries (about 75 g) is about 165 kJ. Half a ripe banana is about 250 kJ and adds natural sweetness
• Sweeteners. One teaspoon of honey is about 90 kJ. One Australian tablespoon (20 mL) is about 350 kJ. Maple syrup and brown sugar also add kilojoules, so measure rather than pour
• Nut butters and nuts. One tablespoon of peanut butter (20 g) is about 500 kJ. A 30 g handful of almonds is about 720 kJ
• Yoghurt. 100 g of natural yoghurt is about 310 kJ and adds around 5 g of protein
• Spices. Cinnamon, nutmeg and vanilla add flavour for almost no kilojoules

A hearty bowl of 40 g oats with half a cup of reduced-fat milk and half a cup of frozen berries comes to roughly 1,000 kJ. Add a tablespoon each of honey and peanut butter and a handful of almonds, and the same bowl of porridge passes 2,500 kJ.

Adding some protein, such as cooking the oats in milk, stirring through natural or Greek yoghurt or having an egg on the side, can make breakfast more satisfying. Our article on protein and appetite explains why.

How to make porridge for weight loss

A lower-kilojoule bowl looks like this:

1. Measure 30–40 g of dry oats rather than free-pouring
2. Cook them in water, or in skim or reduced-fat milk for some extra protein
3. Top with fresh or frozen fruit, such as berries or half a banana, for natural sweetness
4. Flavour with cinnamon, nutmeg or vanilla, which add almost no kilojoules
5. Stir through yoghurt or have an egg on the side for more protein
6. Measure honey, maple syrup, peanut or almond butter, nuts and seeds such as chia seeds, because small amounts add up quickly

When to seek review

If you live with diabetes, a dietitian can help you fit porridge into your carbohydrate plan and choose the type that suits your glucose levels. If you have coeliac disease, check with your doctor or dietitian before including oats. It is also worth getting advice if you’re still hungry mid-morning despite a balanced breakfast, or if your weight isn’t changing over several weeks.

Our dietitians and nurse practitioners can help you build meals that suit your goals. Get in touch.

Frequently asked questions

How much porridge should I eat to lose weight?

A common portion is 30–40 g of dry oats. Half a cup of cooked porridge counts as one grain serve, about 500 kJ.

Is eating porridge every day OK?

Yes, plain porridge can be an everyday breakfast. Oats are a wholegrain, and Australia’s dietary guidelines recommend choosing mostly wholegrain cereal foods; just keep the portion measured and the toppings in check. If you have coeliac disease, check with your doctor or dietitian first.

Should I avoid oats if I want to lose weight?

No. Plain oats in a measured portion suit a weight-loss plan well. It is large portions and energy-dense toppings that add up.

Is porridge better with milk or water?

Water adds no kilojoules. Milk adds protein and calcium, and low-fat options such as reduced-fat or skim milk keep the extra kilojoules lower.

Are instant oats bad for weight loss?

Plain instant oats are nutritionally similar to rolled oats, though digested a little more rapidly. Flavoured sachets often contain added sugar, so check the label.

Are overnight oats as good as cooked porridge?

Yes, soaking instead of cooking doesn’t change the kilojoules much. The toppings and portion matter more.

Are eggs or porridge better for weight loss?

You don’t have to choose. Porridge provides wholegrain fibre, including beta-glucan, and adding protein, such as an egg on the side, can make breakfast more satisfying.

Can eating oats burn belly fat?

No food burns fat from one area. Porridge can help as part of an overall eating pattern that reduces total intake.

Is porridge healthy?

Plain oats are a wholegrain rather than a refined grain, and Australia’s dietary guidelines recommend choosing mostly wholegrain cereal foods. Oats provide fibre, including beta-glucan, which can help lower LDL (“bad”) cholesterol.

Is porridge good for lunch or dinner?

Yes. Porridge works at any meal. For lunch or dinner, add some protein, such as yoghurt stirred through or an egg on the side, so it keeps you full until the next meal.

References

1. Eat for Health (NHMRC). Serve sizes. https://www.eatforhealth.gov.au/food-essentials/how-much-do-we-need-each-day/serve-sizes
2. Eat for Health (NHMRC). Grain (cereal) foods, mostly wholegrain and/or high cereal fibre varieties. https://www.eatforhealth.gov.au/food-essentials/five-food-groups/grain-cereal-foods-mostly-wholegrain-and-or-high-cereal-fibre
3. Food Standards Australia New Zealand. Australian Food Composition Database. https://www.foodstandards.gov.au/science-data/food-nutrient-databases/afcd
4. Rebello CJ, O’Neil CE, Greenway FL. Dietary fiber and satiety: the effects of oats on satiety. Nutr Rev. 2016;74(2):131–47. https://pmc.ncbi.nlm.nih.gov/articles/PMC4757923/
5. Llanaj E, Dejanovic GM, Valido E, et al. Effect of oat supplementation interventions on cardiovascular disease risk markers: a systematic review and meta-analysis of randomized controlled trials. Eur J Nutr. 2022;61(4):1749–78. https://doi.org/10.1007/s00394-021-02763-1
6. Atkinson FS, Brand-Miller JC, Foster-Powell K, Buyken AE, Goletzke J. International tables of glycemic index and glycemic load values 2021: a systematic review. Am J Clin Nutr. 2021;114(5):1625–32. https://doi.org/10.1093/ajcn/nqab233