Last reviewed: July 2026

Potatoes: the most unfairly demonised food in the database

A plain boiled new potato is 73 kcal and 0.3 g of fat per 100 g. Ready salted crisps are 523 kcal and 31 g of fat. That is a sevenfold jump in energy and a hundredfold jump in fat, and the potato is identical in both. Everything people believe about potatoes being fattening is a belief about deep-frying, and it survives because the fried versions are the ones that get eaten. On the evidence, the plain potato is one of the most filling foods ever measured, and it is a better potassium source than the banana it lost the marketing war to.

Figures come from the linked product labels. Frozen chip products are declared as sold, before oven cooking, so the finished figure is a little higher.

The whole story is in the fat column

Read the table left to right and the pattern is unmistakable. Carbohydrate barely moves between a new potato and a bag of crisps once you account for water loss. Fat goes from 0.3 g to 31 g. Sodium goes from 12 mg to 520 mg. What separates the bottom of the table from the top is not the vegetable, it is oil and salt, plus the water that frying drives off and that would otherwise have been filling you up for free. A potato is roughly 79% water. A crisp is roughly 2%. You are not eating the same food in a different shape; you are eating a concentrate.

The oven chip row is the interesting one, because it is the compromise most people actually make. At 169 kcal and 4 g of fat it sits closer to mashed potato than to crisps, and its sodium is 43 mg, lower than the shop-bought mash. Oven chips are not health food, but the gap between them and deep-fried is far larger than the gap between them and a boiled potato.

The satiety evidence, which is genuinely remarkable

In the 1995 satiety index study that ranked 38 common foods by how full they left people after a fixed 240 kcal portion, boiled potatoes came top of the entire list, scoring more than three times white bread. That result has been repeated in the sense that later work on potatoes as a meal component finds them at least as satiating as rice or pasta alongside the same amount of meat. The mechanism is not mysterious: potatoes are heavy, wet and bulky per calorie, which is exactly the profile the satiety explainer describes and exactly what the 500 calories page visualises. It takes about 685 g of boiled new potato to reach 500 kcal, and almost nobody manages that.

This is the part that makes the demonisation strange. If you were designing a food to help someone eat less without feeling deprived, you would design something very close to a plain potato: high water, moderate fibre, low energy density, and a preparation method that does not require added fat.

The potassium fact-check

Bananas own the potassium reputation and potatoes deserve it more. Our baby new potatoes label declares 363 mg of potassium per 100 g, and a realistic 250 g portion of potatoes therefore supplies well over 900 mg, which is a meaningful share of an adult's daily reference intake from one side dish. Potatoes also carry vitamin C, which people rarely associate with them, and a reasonable amount of it survives boiling if you do not boil them to death in a large volume of water. Leave the skins on where the recipe allows, since the skin is where most of the potato's fibre sits and removing it is effort spent making the food slightly worse.

The cooling trick, sized honestly

Cooking then cooling potatoes converts some of their starch into resistant starch, which behaves more like fibre than like sugar and produces a lower glycaemic response. This is real, and it is the reason potato salad tends to test better than hot mash. It is also small. The effect is a modest shift in glycaemic response, not a transformation of the food, and reheating reverses part of it. Treat it as a free bonus when you happen to eat leftover potatoes cold, not as a technique worth reorganising your cooking around. The glycaemic index explainer covers why GI on its own is a poor way to rank a food anyway.

Where the bad reputation actually came from

Three things converged. Low-carbohydrate diets needed a starchy villain and the potato was the most visible one on the plate. Observational studies linking potato consumption to weight gain were widely reported without the detail that the association was driven overwhelmingly by chips and crisps, which is the confound the table above makes obvious. And potatoes have a high glycaemic index, a number that sounds alarming and predicts remarkably little on its own, especially for a food usually eaten with protein and fat as part of a meal. None of those three is an argument against a boiled potato.

How to buy and cook them well

• Default to boiled, steamed or baked. The entire calorie difference in this article is cooking fat. A baked potato is 99 kcal per 100 g before anything goes on it.
• Watch what goes on top, not what is underneath. A tablespoon of butter adds around 100 kcal to a jacket potato, which is more than a third of the potato itself.
• Oven chips are a reasonable middle. At 169 kcal and 4 g of fat per 100 g they cost you far less than the deep-fried version, and the plain ones carry very little sodium.
• Check the sodium on prepared mash. Shop-bought mash runs 160 to 224 mg per 100 g, and dried mash powder can be far higher, which is worth knowing if you are working through the sodium guide.
• Eat the skins when you can. Free fibre, no cost, less peeling.
• Let leftovers go cold. Potato salad is a genuinely good use of yesterday's potatoes, resistant starch included.

The honest limits of this defence

Potatoes are not a protein source, at about 2 g per 100 g, so a plate of them is a side rather than a meal. They are also easy to eat in large amounts precisely because they are pleasant and cheap, and the version most people encounter genuinely is fried. And if your diet is already built on chips, crisps and waffles, the correct conclusion from this page is not that potatoes are fine, it is that the frying is doing the damage and the vegetable underneath is worth rescuing. To see how any two preparations compare on your own shelf, put them into the comparison tool and read the fat row first.

Sources

• National Library of Medicine: a satiety index of common foods, in which boiled potatoes ranked highest of 38 foods
• National Library of Medicine: potatoes and other carbohydrate side dishes on food intake, glycemia and satiety, 2016
• USDA FoodData Central: reference composition for potatoes and potato products