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Carbs explained

The short version: carbs aren't poison, and you don't need to fear a potato. But a lot of us eat more of them than we realise, and cutting back helps plenty of people feel and eat better.

What carbs are

Food is mostly made of three things: protein (meat, fish, eggs), fat (butter, oil) and carbohydrates.

Carbs come as sugars (sweets, fizzy drinks, fruit, milk), starch (bread, pasta, rice, potatoes, cereal) and fibre (veg, beans, wholegrains, nuts). Your body breaks sugars and starch down into glucose, a type of sugar, which it uses for energy. Fibre mostly passes through, which is why UK food labels leave it out of the carbohydrate figure.

What happens when you eat them

Your blood sugar rises. White bread, sugary drinks and sweets are digested quickly. Veg, beans and wholegrains more slowly.
Your body releases insulin. It helps move the sugar out of your blood and into your cells to be used for energy.
Some is stored for later. A little is kept in your muscles and liver. If, overall, you eat more energy than you use, from any food, the extra is stored as body fat.
Hunger comes back. Some people find a meal heavy in sugar or white starch leaves them hungry again sooner than one with more protein and veg.

Why cutting carbs helps a lot of people

It cuts out the easy-to-overeat stuffCrisps, biscuits, pastries and sugary drinks are very easy to have a lot of without feeling full.
Many people find these meals fillingMeals built around protein and veg keep plenty of people going for longer, so snacking drops.
It's simple"Swap the chips for salad" is easier to stick to than counting every calorie.
It can help with type 2 diabetesA UK government advisory committee found a lower-carb diet is an effective short-term option (up to 6 months) for improving blood sugar in adults with type 2 diabetes who are overweight, and said the evidence beyond that is less certain^[1]. If you have diabetes, do it with your GP or nurse.

Weight loss studies generally find lower-carb diets work well early on, and about as well as other approaches over the longer term. The best plan is the one you can keep up.

What standard UK advice says

It's only fair to say that standard NHS advice is different. It suggests starchy foods, ideally wholegrain, make up just over a third of what you eat^[2]^[3], and points out that gram for gram they have fewer than half the calories of fat^[2]. The government's experts also recommend more fibre and less free sugar for everyone^[4].

Lower carb is a choice that suits a lot of people, not a rule. Diabetes UK says low-carb diets can be safe and effective for helping people with type 2 diabetes manage their weight in the short term, and that they're not recommended for children^[5].

Why we eat differently to our grandparents

Sugar was rationedIn Britain, sugar rationing didn't end until 1953. Sweets were a treat.
More food is bought ready-madeReady meals, snacks and takeaways are everywhere, and many are high in sugar or starch.
Sugary drinks are normalFizzy pop, juice and fancy coffees add a lot of sugar without filling you up.
Snacking all dayThere's chocolate and crisps at almost every till.
We move lessMore desk jobs and more driving.

Why it matters for health

WeightIn 2022, 64% of adults in England were overweight or living with obesity, and 29% were living with obesity^[6]. Carrying extra weight raises the risk of type 2 diabetes, heart disease and some cancers.
Type 2 diabetesAbout 4.7 million people in the UK have a diabetes diagnosis, around 90% of them type 2, and almost 1.3 million more may have type 2 without knowing^[7].
Sugar and teethToo much sugar can lead to weight gain and tooth decay^[8].

General information, not medical advice. If you're worried about your health, talk to your GP.

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