The scary truth about bacon – and the best supermarket rashers for your health

Bacon is a staple of the British diet. Sales soar around Christmas as we feast on pigs in blankets, it’s the centrepiece of weekend fry-ups all year round – and nothing compares to a classic bacon sandwich. Deliciously salty and crispy, it also adds flavour to our favourite dishes.

Tempting as it is, the unfortunate truth is that it does absolutely no favours for our health. Calls for packets to be slapped with health warnings are growing among concerned scientists. Considered an ultra-processed food (UPF), Dr Chris van Tulleken, the author of the bestselling book Ultra-Processed People: The Science Behind Food That Isn’t Food, would like to see labels that advise people to cut down. “I would like there to be a public health campaign warning people about the research on UPFs, which is very robust,” he says.

So, why is it so bad for our health and, vitally, how much can we get away with eating?

What exactly is bacon?

“Bacon is derived from various cuts of pork that are cured, either dry or wet,” explains Clare Thornton-Wood, a registered dietitian and British Dietetic Association spokesperson. The dry cured type is rubbed with salt and flavourings, while wet cured is soaked in brine (salt water) and may also be injected with it, she explains.

Bacon is traditionally bought as smoked or unsmoked rashers that are either back bacon (from the loin) or streaky bacon from the belly but it is also available in larger joints which can be boiled or roasted, Thornton-Wood notes.

Per two rashers, unsmoked back bacon has around 120 calories, 8.6g of fat, 3.3g of saturated fat and 1.6g of salt. Smoked, meanwhile, contains slightly less saturated fat (2.8g) but slightly more salt (1.7g). Streaky bacon contains more fat (10.2g) and saturated fat (3.9g) than back bacon but less salt (1.2g).

Why is bacon so bad for you?

1. It contains nitrates and nitrites

Nitrates and nitrites are preservatives that are routinely added to bacon to increase its shelf life, add flavour and enhance its pink-like hue.

These compounds undergo a chemical reaction with the protein in bacon to form toxic chemicals called nitrosamines, which have been linked to bowel and other forms of cancer. As a result, bacon has been classified as carcinogenic by the International Agency for Research on Cancer.

However, nitrates are naturally-occurring and found in vegetables such as rocket, leafy greens, carrots and beetroots.

“In their natural form, nitrates actually have health benefits,” Thornton-Wood says. For example, beetroot juice has been found to lower blood pressure because of its high nitrate content. “The reason there is no risk from vegetables as they are not a rich source of protein [so there isn’t a chemical reaction].”

2. It’s full of saturated fat

Bacon contains up to 4g of saturated fat per two rashers. For comparison, women are supposed to have no more than 20g of saturated fat per day, while men are told to limit themselves to a maximum of 30g – though less is better.

“High intakes of saturated fat have known links with cardiovascular diseases, such as heart attacks and stroke,” Thornton-Wood says.

Saturated fat raises the levels of low-density lipoprotein (LDL) or “bad” cholesterol in the blood, which potentially leads to plaques forming inside arteries and blocking them.

“Fat is also high in calories,” she notes. Each gram of fat contains nine calories, which is more than double the amount of calories found in a gram of carbohydrates or protein. Therefore, it can contribute to weight gain, Thornton-Wood says.

3. It’s ultra-processed

Bacon is classed as an ultra-processed food, meaning it contains ingredients that you wouldn’t find in your kitchen cupboard, Thornton-Wood says. This classification is because of the use of the preservatives sodium nitrite and nitrate, she says.

Diets high in ultra-processed foods have been linked to a greater risk of heart disease, Type 2 diabetes, cancer and poor mental health.

“There is a slight caveat in that if you did make bacon yourself at home with just salt then it would not be ultra-processed,” she notes.

What’s the healthiest way to cook bacon?

To make bacon as healthy as possible, start by buying back bacon or bacon medallions (which is just the lean meat without the fat encircling it), Thornton-Wood recommends.

Next, cut away any remaining excess fat and grill your bacon instead of frying it, she suggests. If you want to stick with frying, make sure not to add any extra fat, such as butter or oil, to the pan when cooking.

Regardless of your method, only cook the bacon until the fat turns golden, she says. If it turns brown or black, it is likely that harmful chemicals called polycyclic aromatic hydrocarbons (PAHs) and heterocyclic amines (HCAs) have been produced, which are known to damage DNA and raise the risk of cancer.

Finally, pat your cooked bacon dry with a kitchen towel after cooking to absorb any excess fat, Thornton-Wood adds.

Serving size and frequency is also important. A portion is two rashers (around 40-60g depending on the type of bacon) and, because of the links between eating red and processed meat with bowel cancer and poor heart health, official UK advice is to consume no more than 70g per day of this category of meat.

While some scientists urge people to forgo all forms of processed meat completely, Thornton-Wood suggests not eating it more frequently than every couple of weeks. Where possible, buy nitrate and nitrite free bacon that’s lower in fat, salt and sugar.

The healthiest supermarket bacon

The following nutritional information is per 100g.

This bacon does not contain any nitrates or nitrites, making it a healthier option than most other types of bacon, Thornton-Wood says.

It is higher in salt than some other varieties, with 3g of salt per 100g, she notes. “But for perspective a couple of rashers is still only going to provide around 1g of your total daily maximum of 6g per day.”

These are an example of bacon medallions, meaning that the visible fat is removed, Thornton-Wood says. As a result, they are about 30 per cent lower in fat and 40 per cent lower in calories than regular bacon, she explains.

This own-brand option is another example of medallions, Thornton-Wood says. “These ones are lower in salt and fat,” she notes.

Another option is turkey bacon, Thornton-Wood says. It contains fewer calories and salt than traditional pork bacon, though it still counts as an ultra-processed food as it contains additives, she says.

This is a plant-based bacon that doesn’t contain nitrites but is still very much an ultra-processed food, Thornton-Wood says. “It’s lower in fat and salt but contains around the same calories as regular bacon,” she notes. “It does contain a small amount of fibre but is lower in protein.”