It also found that the healthier foods had increased in price at twice the rate of the less healthy foods over the past two years.

However, Marilia Chamon, a registered nutritional therapist, points out that some of the healthiest foods are actually the cheapest — if you know what to look for.

She explained: “The key is to focus on foods that give you the most nutrition for your money. My go-to budget-friendly staples include oats, an inexpensive source of fibre and slow-releasing carbohydrates; lentils and beans, which are cheaper than meat but just as filling; and tinned fish, such as sardines [and] mackerel because they are high in healthy fats and protein, and much more affordable than fresh fish.”

Sandra Cohen, a nutritionist who operates via the Doctify website, said many of her clients believe that eating healthily means spending more. However, she believes that with the right strategies, nutritious meals can be affordable.

“It’s about knowing where to shop, what to buy, and how to make the most of ingredients,” she explained. She is a particular fan of frozen fruits and vegetables for budget-friendly, nutrient-dense meals. “They are often cheaper than fresh yet just as, if not more, nutritious since they’re frozen at peak ripeness.”

Cohen also recommends canned goods, including fish, beans, lentils and tomatoes, as affordable alternatives that are full of nutrients. “Look for options with no added sugar or salt,” she added.

Cohen also recommends buying ugly or “wonky” produce. “Subscription services, such as Oddbox, offer surplus or imperfect fruits and vegetables at lower prices, helping reduce waste while keeping costs down.”

All nutritionists recommend cooking from scratch as the best way to maintain a healthy diet while keeping costs low.

Deepak Shukla, the chief executive of Wellness in Italy, a diet and lifestyle adviser, said: “Meal planning prevents waste and overspending. Sticking to a shopping list and buying staples like rice, oats and lentils in bulk helps your budget go further.

“Making whole, unprocessed foods a priority is essential. Legumes, cereals and fresh produce are inexpensive and full of nutrients.”

She added: “You do not need to buy expensive meat to get enough protein. Cheaper options like eggs, beans, and lentils are nutritious and cost less. Unsweetened yoghurt and other dairy alternatives also provide important nutrients at a lower price,” she added.

Buying vegetables in season is another tip that all nutritionists recommend. Toral Shah, a nutritional adviser to Wiley’s Finest, a fish oil brand, says cruciferous vegetables, such as broccoli, cabbage, cauliflower, kale, rocket and watercress, are one of the cheapest foods at this time of year. They are also high in vitamins, minerals and fibre.

She recommended combining shredded cabbage or brussels sprouts with carrots and fresh herbs to create “vibrant coleslaws” or preparing Asian-inspired stir-fries featuring vegetables such as bok choy and daikon, with aromatic combinations of soy, chilli, ginger and garlic.

If you have a sweet tooth and are looking for affordable desert options that are good for you, Alexa Mullane, a nutritionist who specialises in boosting the immune system, recommends apples.

She said: “Apples are abundant right now, and they contain a high amount of the essential antioxidant vitamin C, which can help to prevent colds and flu. They also contain B vitamins which are needed for healthy energy levels.”

What did the Food Foundation research find?

Academics from the University of Cambridge found that healthier foods are now more than twice as expensive per calorie as less healthy foods, with the healthier options increasing in price at twice the rate of less healthy options over the past two years.

How did they come to that conclusion?

The researchers examined the price and nutritional profile of all the foods listed in the Consumer Price Index (CPI) measure of inflation. The team awarded points to products that contained ingredients that the Department for Health considers good for health, such as protein, fruit and vegetables, and took points off products that contained ingredients considered bad for health, such as sodium and saturated fat.

• What salt, sugar, red meat and alcohol really do to your body

The half of products with the highest scores were categorised as “healthier” and the half with the lowest scores were categorised as “less healthy”. The researchers then examined the average price per calorie of the healthier and less healthy products and monitored how the price per calorie had changed over time. The results showed that eating healthier foods was more expensive and the price gap between healthier and less healthy foods had accelerated between 2023 and 2024.

Is that the best way to judge the value of food?

The research is far from flawless but it does at least offer a consistent metric that provides a broad indication of the relative price between foods that are generally better for health and foods that are less good for health and how they are changing over time.

Where does the study fall down?

No methodology is perfect. Imagine two yoghurts that are exactly the same in every respect, and cost exactly the same, except one is low fat. The low-fat one would score as healthier. It would also — by design — have fewer calories. It is true then that, on a cost-per-calorie basis, the low-fat yoghurt is more expensive, but that’s also precisely the point of it.

Any other flaws?

One problem with the approach taken in this study is that it looks at an average across lots of foodstuffs, rather than an average across actual meals. Part of the point of switching to a healthier diet is that you will consume fewer calories. Gunter Kuhnle, of the University of Reading, thinks that this may exaggerate the price difference. He explained: “Most healthy foods are less energy-dense — 1,000 kcal of cucumber would be about 6.6kg (15 kcal/100g) — that’s about £12. So unless there is some adjustment, it will inflate the costs of healthy foods.”

What do the researchers say?

Jean Adams, a professor of diet and public health at the MRC Epidemiology Unit at the University of Cambridge, which conducted the research, said: “Since our conclusions are based on averages, it will be possible to find individual items that are healthy and cheap, as well as expensive, unhealthy ones. This doesn’t negate the finding that, on average, the commonly consumed healthier foods in the Consumer Price Index basket are more expensive than the less healthy ones.