Juliette Kellow, Registered Dietitian and member of the British Dietetic AssociationFocussing on calories has been the gold standard for weight management for decades but, say some experts, it’s an outdated approach. Registered dietitian Juliette Kellow (@juliettekellownutritionist) reviews the pros and cons of calories and delves into their future…

 

MyNutriweb recently held a webinar entitled Why Calories Don’t Count with a thought-provoking and insightful presentation from Dr Giles Yeo, honorary president of the British Dietetic Association and author of a book with the same title. With one of the highest audiences ever, the webinar raised the question of whether calories have had their day.

 

Why calories don’t count

The webinar put forward four main reasons why calories may no longer be a useful tool in helping people manage their weight:

  1. The calories we use today were calculated 120 years ago and fail to consider how our body metabolises them. For example, the body uses 30% of the calories from protein to break it down – but this isn’t factored into current calorie values.
  2. Not all the calories measured in food may be available to us due to the physical structure of a food, the degree of processing or the overall nutrient matrix. Studies measuring digestibility, for example, reveal whole almonds contain 25% fewer calories than stated on nutrition packaging[2].
  3. Calories don’t identify how satiating a food is. The body has to work harder to process protein and fibre, so a food rich in these components can help us feel fuller than a food low in these – even if the calories of both foods are the same.
  4. Calories measure energy only and don’t help us identify diet quality or whether foods are nutrient rich or nutrient poor.

Dr Yeo suggests rather than measuring calories to lose weight and stay heathy, we should focus on increasing protein and fibre intakes, keep sugar intakes low and enjoy some meat-free days – essentially moving towards a more plant-based diet.

It’s a view echoed in the recently published National Food Strategy[3]. In the 290-page report, currently under review by the UK government, calories get only a fleeting mention in relation to the recommendation to introduce a sugar and salt reformulation tax, which modelling suggests would reduce average calories by 15-38kcal per person per day. There’s no recommendation to reduce calories per se. Instead, similar to Dr Yeo’s view, the report recommends eating more fruit, veg and fibre-rich foods, less meat and fewer foods high in fat, sugar and salt.

 

The debate heats up

It’s a way of eating that resonates with many of the key recommendations from health organisations around the world, including the UK. Nevertheless, the government continues to use calories as a key element in public health policies to tackle obesity. For example:

  • In March 2018, Public Health England launched its 400-600-600 calorie campaign[4]. Messaging focused on encouraging adults to stick to 400kcal for breakfast, 600 for lunch and 600 for dinner, plus a couple of healthier snacks and drinks in-between when eating outside the home. The aim: to help adults tackle ‘calorie creep’ that leads to obesity.
  • In September 2020, the government published voluntary calorie reduction targets for the food industry, aimed at reducing excessive calories in everyday foods by up to 20% by 2024[5] to help people move towards and maintain a healthier weight.
  • Most recently, in May 2021 the government announced the introduction of mandatory calorie labelling in out-of-home settings, including restaurants, takeaways and cafes with more than 250 employees from April 2022[6].

It’s easy to see why calories have remained at the centre of government strategies to help tackle overweight and obesity, which currently affects 60% of women and 68% of men in England[7]. The science is unequivocal: the only way to lose weight is to create a calorie deficit, where calorie intake drops below calorie expenditure.

But is focussing on calories the right way to go about achieving this deficit? Government campaigns would suggest so; Dr Giles Yeo, together with many other nutrition experts, disagree.

 

Weighing up the pros and cons

Of course, some consumers may find comparing calorie information useful when trying to decide what to choose when faced with an array of foods and portion sizes. And there are times when monitoring calories is an essential part of the work undertaken by dietitians and nutritionists.

 

When calories count…
  • Focussing on calories is essential for healthcare professionals working with clients whose body weight is at a point where health is severely at risk, for example, someone suffering with anorexia nervosa who has reached a critically low body weight.
  • Calories are an essential calculation for creating weight loss plans to be used in healthcare settings. For example, calorie measurements are needed to put together very low calorie diets sometimes recommended for obese patients, for example, to help manage type 2 diabetes or in preparation for bariatric surgery.

Registered dietitian Dr Duane Mellor, says: For people with type 2 diabetes, especially if aiming for remission of their diabetes, a low-calorie diet can be helpful. If they choose to initially follow a total diet replacement approach using shakes, the calories will be worked out, at least for the weight loss phase. If they want to do a food-based low-calorie diet, then knowledge of calorie contents of food and portion sizes is important so they can be supported in planning their weight loss, and then in the longer term to avoid weight regain. For people with type 1 diabetes, being able to get accurate information about the carbohydrate content of foods to help with insulin doses is more important than calories.”

  • Calculating calorie needs is an essential part of providing nutrition support for ill patients who require oral, enteral or parenteral feeds.
  • Calorie requirements need to be considered and calculated when creating eating plans, menus and resources designed for specific groups of the population.

Nutritionist Fiona Hunter (@fionakhunter) says: Generalised guidance such as ‘eat more fruit and veg, eat more plant-based foods or eat less meat’ can be helpful for the general population. But this type of advice alone isn’t sufficient to put together menus, eating plans or food resources that meet energy (and nutrient) needs for specific groups of people such as children, elderly people or breastfeeding women, or those in specific settings such as hospitals, schools, care homes or prisons. Calories remain a useful tool and a good starting point for developing such plans.”

  • For some, getting enough calories to maintain weight is the issue. Providing advice on calorie-rich foods is therefore needed.

Fiona adds: Recommending more protein and fibre rather than focussing on calories may work for those who want to lose or maintain their weight. But food poverty is also a major problem in the UK with many children – and adults – going hungry due to a lack of food [8]. Malnutrition is also an issue for many elderly people [9]. And people suffering with illness may only have small appetites so need energy-dense foods. For all these groups, concentrating on calories is the priority.”

When calories don’t count…

However, there are many times when calorie counting is unlikely to be the answer, and may, in fact, do more harm than good:

  • Setting calorie limits for meals and snacks removes the ability to respond appropriately to hunger or fullness, so that people eat when they’re not really hungry or finish a meal without feeling satisfied. This moves people even further away from hunger and satiety signals.
  • Focussing on calories doesn’t encourage a balanced, nutrient-rich diet that benefits overall health. Limiting food through reducing calories can mean diets lack protein, fibre, vitamins and minerals. It’s also still easy to eat a lot of processed foods with high intakes of sugar and salt, even if calories are reduced. Plus, focussing on calories can mean some people avoid high-calorie foods that are naturally packaged with nutrients important for a healthy diet.

Registered dietitian Nichola Ludlam-Raine (@nicsnutrition) says: “If we are in an energy deficit (exerting more energy than we are consuming), we will experience weight loss. However, this doesn’t necessarily equal better health. For example, we can eat 1,500kcal of highly processed food that’s lacking in essential nutrients such as vitamins, minerals, fibre and protein. We need to think more about QUALITY over quantity when it comes to calories.”

The British Nutrition Foundation says: “If we only think about calories as numbers, then we might choose to avoid foods that are relatively high in calories but also have a high nutritional value like nuts and seeds, oily fish and olive or rapeseed oil – all of which can be included as part of healthy dietary patterns.”[10]

  • Calorie values don’t reflect the overall nutrition quality of a food or its impact on satiety. There’s a big difference between the nutrients in 200kcal of broccoli and 200kcal of biscuits – and in the portion size to get those calories. You’d need to eat 600g broccoli versus 42g or 2½ chocolate digestives to get 200kcal.

The British Nutrition Foundation says:Foods with similar calorie content can be different in terms of the nutrients they provide. For example, wholegrain versions of bread, pasta and rice are higher in fibre than refined versions. Similarly, processed meats contain more salt than lean unprocessed meats, even if they have a similar number of calories.”[10]

  • It’s easy for calorie counting to become obsessive and, in some people, may trigger an unhealthy relationship with food, potentially leading to eating disorders, diet-binge cycles and mental health issues.

Registered dietitian Laura Clark (@lauraclarknutrition) says: “In a world where so much feels beyond our control, taking explicit control of the calories we’re consuming can feel extremely comforting. But totting up the cals we had for lunch and diligently logging them into an app, which then externally validates whether we’re being compliant, ignores the complexity of the human mind and body – there are so many other factors such as stress, exercise, sleep and our intrinsic beliefs that impact how those calories are utilised.

“Building healthy relationships with food really has nothing to do with calories. Just because something can be measured, doesn’t mean it’s of value to our health and I’ve certainly seen the benefits, emotionally and physically, in the clients I’ve worked with when we take calories off the table.”

Registered dietitian Priya Tew (@priya_tew) says:While calories are a useful guide used in eating disorder recovery, there needs to be a careful balance between using calories to help estimate how much nutrition someone needs in a day / at each meal but not making this a hard and fast rule. Often calories can become a sticking point where every single calorie is counted and going over a limit is not allowed.

“As health professionals, part of our role in this field can be education around how calories in food do not equal calories absorbed by the body, how calories are absorbed differently from different foods and how calories on food labels and menus are not accurate. It is not helpful for someone working on recovery to be tracking their calories but this can be a hard habit to break. Instead, a focus on the balance at meals and the variety of nutrients to include can be more helpful. Having calorie information made more obvious on foods and menus is not helpful to those suffering from an eating disorder and can be hard to hide.”

 

Finding the energy to move forwards

While focussing on calories may be beneficial for some people or essential for healthcare professionals to use in certain circumstances, it’s clear advice for the general population to help them lose or maintain weight AND stay healthy should go beyond simply monitoring calories or attempting to reduce individual nutrients such as sugar in an effort to reduce calories. So what’s the solution? Here are some suggestions… do share your thoughts in the comment box below!

  • A radical change in public health policies and consumer messaging that focusses on food rather than calories or individual nutrients. Preventable ill health, much of which is directly related to poor diets, continues to rise, indicating that existing messaging over the years has failed to work. Health campaigns for the past 30 years have mostly had negative undertones with messaging focussing around limiting single elements of our diet such as calories, sugar, salt or saturated fat. This approach fails to recognise the bigger picture, including the importance of micronutrients and often results in consumers getting confused and losing confidence in expert advice: ‘One minute they’re recommending we cut down on fat, now they’re saying it’s sugar that’s bad for us!’Good nutrition should certainly underpin health policy BUT ultimately people eat food, not nutrients. The policies themselves, together with the activations and communications, should therefore be food focussed rather than calorie or nutrient focussed – and encourage eating more of nutrient-rich foods rather than continuing to beat the same drum that focusses on limiting calories and attempting to limit individual nutrients.
  • In line with this, create a food-based public health campaign that focusses on positive messaging and encourages consumers to enjoy a more plant-based diet, with emphasis on including foods rich in protein and fibre such as beans, lentils, chickpeas and tofu. Dr Yeo recommends at least 16% of calories should come from protein –around 80g based on a 2000kcal diet. The current Reference Nutrient Intake is 0.75kg per kg of body weight for adults. Meanwhile, current intakes of fibre are around 20g in adults[11]. Recommended intakes are at least 30g[12].
  • Work towards building consumer awareness of the role foods rich in protein and fibre can have on satiety and weight management. This could include getting approved health claims for protein and fibre in this area (currently, there are no approved satiety claims for either). Similarly, make it mandatory for nutrition labelling to include values for fibre – currently food manufacturers can choose whether or not to provide this information.
  • Move the story away from weight loss and calorie counting onto food-based eating habits for overall health and wellbeing. Dietitians and nutritionists have a crucial role in spreading this message to anyone who advises on weight management – from other health professionals and personal trainers, to organisations such as slimming clubs or magazines that include diet plans.
  • Implement a ‘nutrition score’ to replace calories and traffic lights on the front of food packaging. Some other countries already do this. In France, for example, food manufacturers voluntarily use the ‘Nutri-score’ system on packaging to help consumers make healthier choices [13]  [14] [15] .Calories are included as just one part of the scoring system, which also includes positive elements such as protein and fibre.

Tanya Haffner RD, CEO of MyNutriWeb, says: “Fifty years ago, when most people were a healthy weight, they didn’t count calories. So, will counting calories help more people reach and maintain a healthy weight now? Irrespective of the inaccuracies surrounding calorie calculations – and the amount we actually process from food – after decades of encouraging people to do so, it seems not.

“Yes, for some few it can help – and certainly for catering provision and menu planning and those working with one-to-one clients, calorie and overall nutrition calculations clearly continue to play a role. However, it’s clear that counting calories isn’t the answer for the population at large.

“I believe we need to see nutrition being translated into communications around food. We’re beginning to see this come through in the recent National Food Strategy recommendations – and we need to see much more. Redeploying budgets and effort into retail and catering policies, nudge tactics around food provision and food promotion, rather than, for example, promoting individual nutrient reduction targets or labelling schemes, would help the nation eat better. I’d like to see food policies that support gradual change for the greater provision and promotion of a plant-based whole foods. It would be wonderful to walk into a store or eat in a restaurant in five years’ time and see that the food provided reflects the food proportions of our national reference diet, The Eatwell Guide, which is currently only achieved by 0.1% of the population[16]. Policies and undoubtedly legislation that support this rather than being calorie driven is what is now urgently needed.”

 

References:

[2] Gebauer SK, Novotny JA. Food Processing and Structure Impact the Metabolizable Energy of Almonds. Food and Function. 2016; 7 (10): 4231–4238. doi: 10.1039/c6fo01076h.

[3] National Food Strategy. Independent Review. The Plan.

[4] Public Health England. Press release: 400-600-600 campaign launches to help adults tackle ‘calorie creep’. Published 6 March 2018.

[5] Gov.UK Press release: New voluntary calorie guidelines to help industry tackle obesity. Published 7 September 2020.

[6] Gov.UK News story: Calorie labelling on menus to be introduced in cafes, restaurants and takeaways.

[7] NHS Digital. Health Survey For England 2019. Published 15 December 2020.

[8] UK Parliament. House of Commons Library. Food Poverty: Households, food banks and free school meals. Published 30 April 2021.

[9] British Dietetic Association. Malnutriton: Food Fact Sheet.

[10] British Nutrition Foundation. The Quality Calorie (QC) Concept.

[11] PHE/FSA (2020) National Diet and Nutrition Survey: Rolling Programme Years 9 to 11 (2016/2017 to 2018/2019).

[12] PHE (2016) Government Dietary Recommendations. Government recommendations for energy and nutrients for males and females aged 1 – 18 years and 19+ years.

[13] Chantal, J and Hercberg, S. Development of a new front-of-pack label in France: the five colour Nutri-Score. Public Health Panorama. 2017; 3 (4), 712-725.

[14] Deschasaux, M et al. Association between nutritional profiles of foods underlying Nutri-Score front-of-pack labels and mortality: EPIC cohort study in 10 European countries. BMJ. 2020; 370.

[15] FoodNavigator.com. Is Nutri-Score working in France? The results are in… Published 5 March 2021.

[16] Scheelbeek, P et al. Health impacts and environmental footprints of diets that meet the Eatwell Guide recommendations: analyses of multiple UK studies. BMJ Open 2020;10:e037554.